U.S. patent application number 16/646491 was filed with the patent office on 2020-08-27 for methods, apparatus and systems for radio link monitoring (rlm) in new radio (nr).
The applicant listed for this patent is IDAC Holdings, Inc.. Invention is credited to Yugeswar Deenoo, Ghyslain Pelletier.
Application Number | 20200274657 16/646491 |
Document ID | / |
Family ID | 1000004828959 |
Filed Date | 2020-08-27 |
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United States Patent
Application |
20200274657 |
Kind Code |
A1 |
Deenoo; Yugeswar ; et
al. |
August 27, 2020 |
METHODS, APPARATUS AND SYSTEMS FOR RADIO LINK MONITORING (RLM) IN
NEW RADIO (NR)
Abstract
Methods, apparatuses, and systems for radio link monitoring
(RLM) implemented by a wireless transmit/receive unit (WTRU) are
provided. A representative method for RLM includes mapping, by the
WTRU, one or more RLM-RS resources to at least one BLER threshold
of a plurality of BLER thresholds. The representative method also
includes, for each respective RLM resource that is mapped,
determining, by the WTRU, a BLER of the respective RLM-RS resource,
and comparing the determined BLER of the respective RLM-RS resource
with the at least one mapped BLER threshold associated with the
respective RLM-RS resource. The representative method further
includes generating, based on one or more of the comparisons, a set
of in-sync indications and/or a set of out-of-sync indications, and
indicating, by the WTRU, one or more attributes associated with the
set of in-sync indications and/or the set of out-of-sync
indications.
Inventors: |
Deenoo; Yugeswar; (Chalfont,
PA) ; Pelletier; Ghyslain; (Montreal, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
IDAC Holdings, Inc. |
Wilmington |
DE |
US |
|
|
Family ID: |
1000004828959 |
Appl. No.: |
16/646491 |
Filed: |
August 31, 2018 |
PCT Filed: |
August 31, 2018 |
PCT NO: |
PCT/US18/49042 |
371 Date: |
March 11, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62557083 |
Sep 11, 2017 |
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62586271 |
Nov 15, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L 1/0021 20130101;
H04L 5/005 20130101; H04W 76/27 20180201; H04L 1/0026 20130101;
H04L 1/203 20130101; H04W 36/0058 20180801; H04W 24/08 20130101;
H04W 76/18 20180201; H04L 5/0075 20130101 |
International
Class: |
H04L 1/20 20060101
H04L001/20; H04L 5/00 20060101 H04L005/00; H04W 24/08 20060101
H04W024/08; H04L 1/00 20060101 H04L001/00; H04W 36/00 20060101
H04W036/00; H04W 76/27 20060101 H04W076/27; H04W 76/18 20060101
H04W076/18 |
Claims
1. A method implemented by a wireless transmit/receive unit (WTRU)
configured for radio link monitoring (RLM), comprising: mapping, by
the WTRU, one or more RLM reference signal (RLM-RS) resources to at
least one Block Error Ratio (BLER) threshold of a plurality of BLER
thresholds; for each respective RLM resource that is mapped:
determining, by the WTRU, a BLER of the respective RLM-RS resource,
and comparing the determined BLER of the respective RLM-RS resource
with the at least one mapped BLER threshold associated with the
respective RLM-RS resource; generating, based on one or more of the
comparisons, a set of in-sync indications and/or a set of
out-of-sync indications; and indicating, by the WTRU, one or more
attributes associated with the set of in-sync indications and/or
the set of out-of-sync indications.
2. The method of claim 1, wherein a respective BLER threshold of
the plurality of BLER threshold is associated with a service
type.
3. The method of claim 2, wherein the service type is any of:
ultra-reliable low latency (URLLC), enhanced massive mobile
broadband (eMBB), or enhanced machine-type communication
(eMTC).
4. The method of claim 1, wherein the one or more attributes
indicate any of: a respective RLM-RS resource, an RLM-RS resource
group, or an RLM-RS type associated with the set of in-sync
indications and/or the set of out-of-sync indications; a CORESET or
a CORESET group associated with the set of in-sync indications
and/or the set of out-of-sync indications; a beam group associated
with the set of in-sync indications and/or the set of out-of-sync
indications; and a respective BLER threshold associated with the
set of in-sync indications and/or the set of out-of-sync
indications.
5. The method of claim 1, further comprising: obtaining, by the
WTRU, a type of service associated with a communication; and
selecting, by the WTRU, the at least one BLER threshold in
accordance with the obtained type of service.
6. The method of claim 1, wherein: the mapping of the one or more
RLM-RS resources includes mapping of each respective RLM-RS
resource to one BLER threshold of the plurality of BLER thresholds;
and the comparing of the determined BLER of the respective RLM-RS
resource with the at least one mapped BLER threshold includes
comparing of the determined BLER of each respective RLM-RS resource
to the at least one mapped BLER threshold.
7. The method of claim 1, further comprising: grouping two or more
of the RLM-RS resources that are associated with any of: one
CORESET, a group of CORESETs, and a beam group; determining a
composite BLER specific to the grouped RLM-RS resources based on
the determined BLER; and comparing the composite BLER specific to
the grouped RLM-RS resources with one of the at least one mapped
BLER threshold.
8. The method of claim 1, wherein the generating of the set of
in-sync indications and/or the set of out-of-sync indications
includes generating the set of one or more in-sync indications
and/or the set of one or more out-of-sync indications for: (1) each
comparison of the determined BLER of the respective RLM-RS resource
with the at least one mapped BLER threshold associated with the
respective RLM-RS resource, or (2) a set of comparisons associated
with the grouped RLM-RS resources.
9. The method of claim 1, wherein the generating of the set of
in-sync indications and/or the set of out-of-sync indications
includes generating the set of one or more in-sync indications
and/or the set of one or more out-of-sync indications associated
with: (1) the at least one mapped BLER threshold; (2) a subset of
the at least one mapped BLER threshold; or (3) for each of the at
least one mapped BLER threshold.
10. The method of claim 1, wherein: the mapping of the one or more
RLM-RS resources includes mapping each RLM-RS resource to two or
more BLER thresholds of the plurality of BLER thresholds; and the
comparing of the determined BLER of the respective RLM-RS resource
with the at least one mapped BLER threshold includes comparing of
the determined BLER associated with each respective RLM-RS resource
or a group of RLM-RS resources to the two or more mapped BLER
thresholds.
11. The method of claim 1, wherein the generating of the set of
in-sync indications and/or the set of out-of-sync indications
includes generating a composite set of in-sync indications and/or
out-of-sync indications for each of the at least one mapped BLER
thresholds or N composite sets of in-sync indications and/or
out-of-sync indications for M BLER thresholds, where N and M are
positive integer values, and N is less than or equal to M.
12. The method of claim 1, further comprising: determining, prior
to the mapping, a first set of BLER thresholds of the plurality of
BLER thresholds to be mapped with the one or more RLM-RS
resources.
13. The method of claim 12, further comprising: determining, after
the mapping, that a second set of BLER thresholds of the plurality
of BLER thresholds is be mapped with the one or more RLM-RS
resources and/or other RLM-RS resources; and modifying from a
mapping of the one or more RLM-RS resources with the first set of
BLER thresholds to a different mapping of the one or more RLM-RS
resources and/or the other RLM-RS resources with the second set of
BLER thresholds or remapping the one or more RLM-RS resources
and/or the other RLM-RS resources with the second set of BLER
thresholds, wherein the comparing of the determined BLER with the
at least one mapped BLER threshold includes comparing the
determined BLER of the respective RLM-RS resources with the second
set of modified or remapped BLER thresholds.
14-15. (canceled)
16. The method of claim 1, further comprising: reconfiguring at
least one BLER threshold of the plurality of BLER thresholds from a
first BLER threshold to a second BLER threshold.
17. The method of claim 16, wherein after the reconfiguring, the
one or more attributes associated with the set of in-sync
indications and/or the set of out-of-sync indications are based on
a configuration of an RLM process prior to and after the
reconfiguration.
18-25. (canceled)
26. A method, implemented by a wireless transmit/receive unit
(WTRU), to transition from a first Radio Resource Control (RRC)
configuration to a second RRC configuration, as an RCC
reconfiguration, the method comprising: receiving, by the WTRU, the
second RRC configuration indicating a first set of Block Error
Ratio (BLER) thresholds that is different from one or more BLER
thresholds indicated in the first RRC configuration; generating,
based on the first set of BLER thresholds after reception of the
second RRC configuration, one or more in-sync indications and/or
one or more out-of-sync indications; and indicating, by the WTRU,
one or more attributes associated with the one or more in-sync
indications and/or the one or more out-of-sync indications.
27. The method of claim 26, wherein indicating of the one or more
attributes associated with the one or more in-sync indications
and/or the one or more out-of-sync indications includes
compensating, by the WTRU based on at least an existing RLM status,
for a difference between the first RRC configuration and the second
RRC configuration as part of the transition from the first RRC
configuration to the second RRC configuration.
28. The method of claim 27, wherein compensating for the difference
between the first RRC configuration and the second RRC
configuration includes any of: (1) applying a penalty to counters
and/or timers to account for differences in an ongoing RLM process;
(2) applying fairness to avoid a premature radio link failure
(RLF); (3) updating an expiry of a timer to avoid an RLF until
after expiry of the updated timer; or (4) continuing an RLM process
or resetting an RLM process selectively based on one or more rules
to avoid the premature RLF or a delayed RLF.
29-44. (canceled)
45. A method, implemented by a wireless transmit/receive unit
(WTRU), to transition from a first Radio Resource Control (RRC)
configuration having first BLER thresholds to a second RRC
configuration having second BLER thresholds, the method comprising:
receiving the second RRC configuration; determining a compensation
for a new RRC configuration process associated with the second RRC
configuration during a transition to the second RRC configuration
based on an existing RLM status; determining whether a Radio Link
Failure (RLF) has occurred based on the second BLER thresholds
associated with the second RRC configuration and the determined
compensation; and sending, by the WTRU, a message, on condition
that the RLF occurred.
46. A wireless transmit/receive unit (WTRU) comprising a processor,
a receiver, a transmitter, and memory configured to perform the
method of any one of the preceding claims.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and the benefit of U.S.
Provisional Application No. 62/557,083 filed in the U.S. Patent and
Trademark Office on Sep. 11, 2017, and U.S. Provisional Application
No. 62/586,271 filed in the U.S. Patent and Trademark Office on
Nov. 15, 2017, the entire contents of each of which being
incorporated herein by reference as if fully set forth below in
their entirety and for all applicable purposes.
FIELD
[0002] The field of the disclosure relates to communications and,
more particularly, to methods, apparatus, and systems for
communications in an advanced or next generation wireless
communications system, including communications for Radio Link
Monitoring (RLM) and/or reconfigurations of RLM process in 5G New
Radio (NR).
RELATED ART
[0003] In Long Term Evolution (LTE), RLM is used to determine radio
link failures.
SUMMARY
[0004] A representative device has circuitry, including any of a
processor, memory, a receiver, and a transmitter. In an example,
the processor may be configured to map one or more RLM reference
signal (RLM-RS) resources to at least one Block Error Ratio (BLER)
threshold of a plurality of BLER thresholds, and for each
respective RLM resource that is mapped, the processor may be
configured to determine a BLER of the respective RLM-RS resource,
and compare the determined BLER of the respective RLM-RS resource
with the at least one mapped BLER threshold associated with the
respective RLM-RS resource. The processor may be further configured
to generate, based on one or more of the comparisons, a set of
in-sync indications and/or a set of out-of-sync indications, and
indicate one or more attributes associated with the set of in-sync
indications and/or the set of out-of-sync indications.
[0005] Methods, apparatuses, and systems for RLM implemented in a
transmitter/receiver are provided. In an example, a representative
method implemented by a wireless transmit/receive unit (WTRU)
configured for RLM may include mapping, by the WTRU, one or more
RLM-RS resources to at least one BLER threshold of a plurality of
BLER thresholds. The representative method may also include, for
each respective RLM resource that is mapped, determining, by the
WTRU, a BLER of the respective RLM-RS resource, and comparing the
determined BLER of the respective RLM-RS resource with the at least
one mapped BLER threshold associated with the respective RLM-RS
resource. The representative method may further include generating,
based on one or more of the comparisons, a set of in-sync
indications and/or a set of out-of-sync indications, and
indicating, by the WTRU, one or more attributes associated with the
set of in-sync indications and/or the set of out-of-sync
indications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] A more detailed understanding may be had from the detailed
description below, given by way of example in conjunction with
drawings appended hereto. Figures in description, are examples. As
such, the figures and the detailed description are not to be
considered limiting, and other equally effective examples are
possible and likely. Furthermore, like reference numerals in the
figures indicate like elements, and wherein:
[0007] FIG. 1A is a system diagram illustrating an example
communications system in which one or more disclosed embodiments
may be implemented;
[0008] FIG. 1B is a system diagram illustrating an example wireless
transmit/receive unit (WTRU) that may be used within the
communications system illustrated in FIG. 1A according to an
embodiment;
[0009] FIG. 1C is a system diagram illustrating an example radio
access network (RAN) and an example core network (CN) that may be
used within the communications system illustrated in FIG. 1A
according to an embodiment;
[0010] FIG. 1D is a system diagram illustrating a further example
RAN and a further example CN that may be used within the
communications system illustrated in FIG. 1A according to an
embodiment;
[0011] FIG. 2 is a diagram illustrating modeling of a
representative RLM procedure in an Long Term Evolution (LTE)
network;
[0012] FIG. 3 is a diagram illustrating representative comparison
procedures having one BLER threshold;
[0013] FIG. 4 is a diagram illustrating representative comparison
procedures having two or more BLER thresholds;
[0014] FIG. 5 is a diagram illustrating other representative
comparison procedures having two or more BLER thresholds;
[0015] FIG. 6 is a diagram illustrating additional representative
comparison procedures having two or more BLER thresholds;
[0016] FIG. 7 is a diagram illustrating yet other representative
comparison procedures having two or more BLER thresholds;
[0017] FIG. 8 is a diagram illustrating a representative RLM
framework;
[0018] FIG. 9 is a diagram illustrating a first representative RLM
process for reconfiguration of one or more BLER thresholds;
[0019] FIG. 10 is a diagram illustrating a second representative
RLM process for reconfiguration of one or more BLER thresholds;
[0020] FIG. 11 is a diagram illustrating a third representative RLM
process for reconfiguration of one or more BLER thresholds;
[0021] FIG. 12 is a diagram illustrating examples of RLM-RS
reconfigurations;
[0022] FIG. 23 is a diagram illustrating a first method of an RLM
procedure according to one or more embodiments;
[0023] FIG. 14 is a diagram illustrating a method of a Radio
Resource Control (RRC) reconfiguration for an RLM procedure
according to one or more embodiments;
[0024] FIG. 35 is a diagram illustrating a second method of an RLM
procedure according to one or more embodiments;
[0025] FIG. 16 is a diagram illustrating a first method of RLM and
supplementary uplink (SUL) transmissions according to one or more
embodiments; and
[0026] FIG. 17 is a diagram illustrating a second method of RLM and
SUL transmissions according to one or more embodiments.
DETAILED DESCRIPTION
[0027] FIG. 1A is a diagram illustrating an example communications
system 100 in which one or more disclosed embodiments may be
implemented. The communications system 100 may be a multiple access
system that provides content, such as voice, data, video,
messaging, broadcast, etc., to multiple wireless users. The
communications system 100 may enable multiple wireless users to
access such content through the sharing of system resources,
including wireless bandwidth. For example, the communications
systems 100 may employ one or more channel access methods, such as
code division multiple access (CDMA), time division multiple access
(TDMA), frequency division multiple access (FDMA), orthogonal FDMA
(OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique-word
DFT-Spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM),
resource block-filtered OFDM, filter bank multicarrier (FBMC), and
the like.
[0028] As shown in FIG. 1A, the communications system 100 may
include wireless transmit/receive units (WTRUs) 102a, 102b, 102c,
102d, a RAN 104/113, a CN 106/115, a public switched telephone
network (PSTN) 108, the Internet 110, and other networks 112,
though it will be appreciated that the disclosed embodiments
contemplate any number of WTRUs, base stations, networks, and/or
network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be
any type of device configured to operate and/or communicate in a
wireless environment. By way of example, the WTRUs 102a, 102b,
102c, 102d, any of which may be referred to as a "station" and/or a
"STA", may be configured to transmit and/or receive wireless
signals and may include a user equipment (UE), a mobile station, a
fixed or mobile subscriber unit, a subscription-based unit, a
pager, a cellular telephone, a personal digital assistant (PDA), a
smartphone, a laptop, a netbook, a personal computer, a wireless
sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT)
device, a watch or other wearable, a head-mounted display (HMD), a
vehicle, a drone, a medical device and applications (e.g., remote
surgery), an industrial device and applications (e.g., a robot
and/or other wireless devices operating in an industrial and/or an
automated processing chain contexts), a consumer electronics
device, a device operating on commercial and/or industrial wireless
networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d
may be interchangeably referred to as a UE.
[0029] The communications systems 100 may also include a base
station 114a and/or a base station 114b. Each of the base stations
114a, 114b may be any type of device configured to wirelessly
interface with at least one of the WTRUs 102a, 102b, 102c, 102d to
facilitate access to one or more communication networks, such as
the CN 106/115, the Internet 110, and/or the other networks 112. By
way of example, the base stations 114a, 114b may be a base
transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a
Home eNode B, a gNB, a NR NodeB, a site controller, an access point
(AP), a wireless router, and the like. While the base stations
114a, 114b are each depicted as a single element, it will be
appreciated that the base stations 114a, 114b may include any
number of interconnected base stations and/or network elements.
[0030] The base station 114a may be part of the RAN 104/113, which
may also include other base stations and/or network elements (not
shown), such as a base station controller (BSC), a radio network
controller (RNC), relay nodes, etc. The base station 114a and/or
the base station 114b may be configured to transmit and/or receive
wireless signals on one or more carrier frequencies, which may be
referred to as a cell (not shown). These frequencies may be in
licensed spectrum, unlicensed spectrum, or a combination of
licensed and unlicensed spectrum. A cell may provide coverage for a
wireless service to a specific geographical area that may be
relatively fixed or that may change over time. The cell may further
be divided into cell sectors. For example, the cell associated with
the base station 114a may be divided into three sectors. Thus, in
one embodiment, the base station 114a may include three
transceivers, i.e., one for each sector of the cell. In an
embodiment, the base station 114a may employ multiple-input
multiple output (MIMO) technology and may utilize multiple
transceivers for each sector of the cell. For example, beamforming
may be used to transmit and/or receive signals in desired spatial
directions.
[0031] The base stations 114a, 114b may communicate with one or
more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116,
which may be any suitable wireless communication link (e.g., radio
frequency (RF), microwave, centimeter wave, micrometer wave,
infrared (IR), ultraviolet (UV), visible light, etc.). The air
interface 116 may be established using any suitable radio access
technology (RAT).
[0032] More specifically, as noted above, the communications system
100 may be a multiple access system and may employ one or more
channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA,
and the like. For example, the base station 114a in the RAN 104/113
and the WTRUs 102a, 102b, 102c may implement a radio technology
such as Universal Mobile Telecommunications System (UMTS)
Terrestrial Radio Access (UTRA), which may establish the air
interface 115/116/117 using wideband CDMA (WCDMA). WCDMA may
include communication protocols such as High-Speed Packet Access
(HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed
Downlink (DL) Packet Access (HSDPA) and/or High-Speed UL Packet
Access (HSUPA).
[0033] In an embodiment, the base station 114a and the WTRUs 102a,
102b, 102c may implement a radio technology such as Evolved UMTS
Terrestrial Radio Access (E-UTRA), which may establish the air
interface 116 using Long Term Evolution (LTE) and/or LTE-Advanced
(LTE-A) and/or LTE-Advanced Pro (LTE-A Pro).
[0034] In an embodiment, the base station 114a and the WTRUs 102a,
102b, 102c may implement a radio technology such as NR Radio
Access, which may establish the air interface 116 using New Radio
(NR).
[0035] In an embodiment, the base station 114a and the WTRUs 102a,
102b, 102c may implement multiple radio access technologies. For
example, the base station 114a and the WTRUs 102a, 102b, 102c may
implement LTE radio access and NR radio access together, for
instance using dual connectivity (DC) principles. Thus, the air
interface utilized by WTRUs 102a, 102b, 102c may be characterized
by multiple types of radio access technologies and/or transmissions
sent to/from multiple types of base stations (e.g., an eNB and a
gNB).
[0036] In other embodiments, the base station 114a and the WTRUs
102a, 102b, 102c may implement radio technologies such as IEEE
802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e.,
Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000,
CDMA2000 1.times., CDMA2000 EV-DO, Interim Standard 2000 (IS-2000),
Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global
System for Mobile communications (GSM), Enhanced Data rates for GSM
Evolution (EDGE), GSM EDGE (GERAN), and the like.
[0037] The base station 114b in FIG. 1A may be a wireless router,
Home Node B, Home eNode B, or access point, for example, and may
utilize any suitable RAT for facilitating wireless connectivity in
a localized area, such as a place of business, a home, a vehicle, a
campus, an industrial facility, an air corridor (e.g., for use by
drones), a roadway, and the like. In one embodiment, the base
station 114b and the WTRUs 102c, 102d may implement a radio
technology such as IEEE 802.11 to establish a wireless local area
network (WLAN). In an embodiment, the base station 114b and the
WTRUs 102c, 102d may implement a radio technology such as IEEE
802.15 to establish a wireless personal area network (WPAN). In yet
another embodiment, the base station 114b and the WTRUs 102c, 102d
may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE,
LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. As
shown in FIG. 1A, the base station 114b may have a direct
connection to the Internet 110. Thus, the base station 114b may not
be required to access the Internet 110 via the CN 106/115.
[0038] The RAN 104/113 may be in communication with the CN 106/115,
which may be any type of network configured to provide voice, data,
applications, and/or voice over internet protocol (VoIP) services
to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may
have varying quality of service (QoS) requirements, such as
differing throughput requirements, latency requirements, error
tolerance requirements, reliability requirements, data throughput
requirements, mobility requirements, and the like. The CN 106/115
may provide call control, billing services, mobile location-based
services, pre-paid calling, Internet connectivity, video
distribution, etc., and/or perform high-level security functions,
such as user authentication. Although not shown in FIG. 1A, it will
be appreciated that the RAN 104/113 and/or the CN 106/115 may be in
direct or indirect communication with other RANs that employ the
same RAT as the RAN 104/113 or a different RAT. For example, in
addition to being connected to the RAN 104/113, which may be
utilizing a NR radio technology, the CN 106/115 may also be in
communication with another RAN (not shown) employing a GSM, UMTS,
CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.
[0039] The CN 106/115 may also serve as a gateway for the WTRUs
102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110,
and/or the other networks 112. The PSTN 108 may include
circuit-switched telephone networks that provide plain old
telephone service (POTS). The Internet 110 may include a global
system of interconnected computer networks and devices that use
common communication protocols, such as the transmission control
protocol (TCP), user datagram protocol (UDP) and/or the internet
protocol (IP) in the TCP/IP internet protocol suite. The networks
112 may include wired and/or wireless communications networks owned
and/or operated by other service providers. For example, the
networks 112 may include another CN connected to one or more RANs,
which may employ the same RAT as the RAN 104/113 or a different
RAT.
[0040] Some or all of the WTRUs 102a, 102b, 102c, 102d in the
communications system 100 may include multi-mode capabilities
(e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple
transceivers for communicating with different wireless networks
over different wireless links) For example, the WTRU 102c shown in
FIG. 1A may be configured to communicate with the base station
114a, which may employ a cellular-based radio technology, and with
the base station 114b, which may employ an IEEE 802 radio
technology.
[0041] FIG. 1B is a system diagram illustrating an example WTRU
102. As shown in FIG. 1B, the WTRU 102 may include a processor 118,
a transceiver 120, a transmit/receive element 122, a
speaker/microphone 124, a keypad 126, a display/touchpad 128,
non-removable memory 130, removable memory 132, a power source 134,
a global positioning system (GPS) chipset 136, and/or other
peripherals 138, among others. It will be appreciated that the WTRU
102 may include any sub-combination of the foregoing elements while
remaining consistent with an embodiment.
[0042] The processor 118 may be a general purpose processor, a
special purpose processor, a conventional processor, a digital
signal processor (DSP), a plurality of microprocessors, one or more
microprocessors in association with a DSP core, a controller, a
microcontroller, Application Specific Integrated Circuits (ASICs),
Field Programmable Gate Arrays (FPGAs) circuits, any other type of
integrated circuit (IC), a state machine, and the like. The
processor 118 may perform signal coding, data processing, power
control, input/output processing, and/or any other functionality
that enables the WTRU 102 to operate in a wireless environment. The
processor 118 may be coupled to the transceiver 120, which may be
coupled to the transmit/receive element 122. While FIG. 1B depicts
the processor 118 and the transceiver 120 as separate components,
it will be appreciated that the processor 118 and the transceiver
120 may be integrated together in an electronic package or
chip.
[0043] The transmit/receive element 122 may be configured to
transmit signals to, or receive signals from, a base station (e.g.,
the base station 114a) over the air interface 116. For example, in
one embodiment, the transmit/receive element 122 may be an antenna
configured to transmit and/or receive RF signals. In an embodiment,
the transmit/receive element 122 may be an emitter/detector
configured to transmit and/or receive IR, UV, or visible light
signals, for example. In yet another embodiment, the
transmit/receive element 122 may be configured to transmit and/or
receive both RF and light signals. It will be appreciated that the
transmit/receive element 122 may be configured to transmit and/or
receive any combination of wireless signals.
[0044] Although the transmit/receive element 122 is depicted in
FIG. 1B as a single element, the WTRU 102 may include any number of
transmit/receive elements 122. More specifically, the WTRU 102 may
employ MIMO technology. Thus, in one embodiment, the WTRU 102 may
include two or more transmit/receive elements 122 (e.g., multiple
antennas) for transmitting and receiving wireless signals over the
air interface 116.
[0045] The transceiver 120 may be configured to modulate the
signals that are to be transmitted by the transmit/receive element
122 and to demodulate the signals that are received by the
transmit/receive element 122. As noted above, the WTRU 102 may have
multi-mode capabilities. Thus, the transceiver 120 may include
multiple transceivers for enabling the WTRU 102 to communicate via
multiple RATs, such as NR and IEEE 802.11, for example.
[0046] The processor 118 of the WTRU 102 may be coupled to, and may
receive user input data from, the speaker/microphone 124, the
keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal
display (LCD) display unit or organic light-emitting diode (OLED)
display unit). The processor 118 may also output user data to the
speaker/microphone 124, the keypad 126, and/or the display/touchpad
128. In addition, the processor 118 may access information from,
and store data in, any type of suitable memory, such as the
non-removable memory 130 and/or the removable memory 132. The
non-removable memory 130 may include random-access memory (RAM),
read-only memory (ROM), a hard disk, or any other type of memory
storage device. The removable memory 132 may include a subscriber
identity module (SIM) card, a memory stick, a secure digital (SD)
memory card, and the like. In other embodiments, the processor 118
may access information from, and store data in, memory that is not
physically located on the WTRU 102, such as on a server or a home
computer (not shown).
[0047] The processor 118 may receive power from the power source
134, and may be configured to distribute and/or control the power
to the other components in the WTRU 102. The power source 134 may
be any suitable device for powering the WTRU 102. For example, the
power source 134 may include one or more dry cell batteries (e.g.,
nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride
(NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and
the like.
[0048] The processor 118 may also be coupled to the GPS chipset
136, which may be configured to provide location information (e.g.,
longitude and latitude) regarding the current location of the WTRU
102. In addition to, or in lieu of, the information from the GPS
chipset 136, the WTRU 102 may receive location information over the
air interface 116 from a base station (e.g., base stations 114a,
114b) and/or determine its location based on the timing of the
signals being received from two or more nearby base stations. It
will be appreciated that the WTRU 102 may acquire location
information by way of any suitable location-determination method
while remaining consistent with an embodiment.
[0049] The processor 118 may further be coupled to other
peripherals 138, which may include one or more software and/or
hardware modules that provide additional features, functionality
and/or wired or wireless connectivity. For example, the peripherals
138 may include an accelerometer, an e-compass, a satellite
transceiver, a digital camera (for photographs and/or video), a
universal serial bus (USB) port, a vibration device, a television
transceiver, a hands free headset, a Bluetooth.RTM. module, a
frequency modulated (FM) radio unit, a digital music player, a
media player, a video game player module, an Internet browser, a
Virtual Reality and/or Augmented Reality (VR/AR) device, an
activity tracker, and the like. The peripherals 138 may include one
or more sensors, the sensors may be one or more of a gyroscope, an
accelerometer, a hall effect sensor, a magnetometer, an orientation
sensor, a proximity sensor, a temperature sensor, a time sensor; a
geolocation sensor; an altimeter, a light sensor, a touch sensor, a
magnetometer, a barometer, a gesture sensor, a biometric sensor,
and/or a humidity sensor.
[0050] The WTRU 102 may include a full duplex radio for which
transmission and reception of some or all of the signals (e.g.,
associated with particular subframes for both the UL (e.g., for
transmission) and downlink (e.g., for reception) may be concurrent
and/or simultaneous. The full duplex radio may include an
interference management unit 139 to reduce and or substantially
eliminate self-interference via either hardware (e.g., a choke) or
signal processing via a processor (e.g., a separate processor (not
shown) or via processor 118). In an embodiment, the WRTU 102 may
include a half-duplex radio for which transmission and reception of
some or all of the signals (e.g., associated with particular
subframes for either the UL (e.g., for transmission) or the
downlink (e.g., for reception)).
[0051] FIG. 1C is a system diagram illustrating the RAN 104 and the
CN 106 according to an embodiment. As noted above, the RAN 104 may
employ an E-UTRA radio technology to communicate with the WTRUs
102a, 102b, 102c over the air interface 116. The RAN 104 may also
be in communication with the CN 106.
[0052] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it
will be appreciated that the RAN 104 may include any number of
eNode-Bs while remaining consistent with an embodiment. The
eNode-Bs 160a, 160b, 160c may each include one or more transceivers
for communicating with the WTRUs 102a, 102b, 102c over the air
interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may
implement MIMO technology. Thus, the eNode-B 160a, for example, may
use multiple antennas to transmit wireless signals to, and/or
receive wireless signals from, the WTRU 102a.
[0053] Each of the eNode-Bs 160a, 160b, 160c may be associated with
a particular cell (not shown) and may be configured to handle radio
resource management decisions, handover decisions, scheduling of
users in the UL and/or DL, and the like. As shown in FIG. 1C, the
eNode-Bs 160a, 160b, 160c may communicate with one another over an
X2 interface.
[0054] The CN 106 shown in FIG. 1C may include a mobility
management entity (MME) 162, a serving gateway (SGW) 164, and a
packet data network (PDN) gateway (or PGW) 166. While each of the
foregoing elements are depicted as part of the CN 106, it will be
appreciated that any of these elements may be owned and/or operated
by an entity other than the CN operator.
[0055] The MME 162 may be connected to each of the eNode-Bs 160a,
160b, 160c in the RAN 104 via an S1 interface and may serve as a
control node. For example, the MME 162 may be responsible for
authenticating users of the WTRUs 102a, 102b, 102c, bearer
activation/deactivation, selecting a particular serving gateway
during an initial attach of the WTRUs 102a, 102b, 102c, and the
like. The MME 162 may provide a control plane function for
switching between the RAN 104 and other RANs (not shown) that
employ other radio technologies, such as GSM and/or WCDMA.
[0056] The SGW 164 may be connected to each of the eNode-Bs 160a,
160b, 160c in the RAN 104 via the S1 interface. The SGW 164 may
generally route and forward user data packets to/from the WTRUs
102a, 102b, 102c. The SGW 164 may perform other functions, such as
anchoring user planes during inter-eNode-B handovers, triggering
paging when DL data is available for the WTRUs 102a, 102b, 102c,
managing and storing contexts of the WTRUs 102a, 102b, 102c, and
the like.
[0057] The SGW 164 may be connected to the PGW 166, which may
provide the WTRUs 102a, 102b, 102c with access to packet-switched
networks, such as the Internet 110, to facilitate communications
between the WTRUs 102a, 102b, 102c and IP-enabled devices.
[0058] The CN 106 may facilitate communications with other
networks. For example, the CN 106 may provide the WTRUs 102a, 102b,
102c with access to circuit-switched networks, such as the PSTN
108, to facilitate communications between the WTRUs 102a, 102b,
102c and traditional land-line communications devices. For example,
the CN 106 may include, or may communicate with, an IP gateway
(e.g., an IP multimedia subsystem (IMS) server) that serves as an
interface between the CN 106 and the PSTN 108. In addition, the CN
106 may provide the WTRUs 102a, 102b, 102c with access to the other
networks 112, which may include other wired and/or wireless
networks that are owned and/or operated by other service
providers.
[0059] Although the WTRU is described in FIGS. 1A-1D as a wireless
terminal, it is contemplated that in certain representative
embodiments that such a terminal may use (e.g., temporarily or
permanently) wired communication interfaces with the communication
network.
[0060] In representative embodiments, the other network 112 may be
a WLAN.
[0061] A WLAN in Infrastructure Basic Service Set (BSS) mode may
have an Access Point (AP) for the BSS and one or more stations
(STAs) associated with the AP. The AP may have an access or an
interface to a Distribution System (DS) or another type of
wired/wireless network that carries traffic in to and/or out of the
BSS. Traffic to STAs that originates from outside the BSS may
arrive through the AP and may be delivered to the STAs. Traffic
originating from STAs to destinations outside the BSS may be sent
to the AP to be delivered to respective destinations. Traffic
between STAs within the BSS may be sent through the AP, for
example, where the source STA may send traffic to the AP and the AP
may deliver the traffic to the destination STA. The traffic between
STAs within a BSS may be considered and/or referred to as
peer-to-peer traffic. The peer-to-peer traffic may be sent between
(e.g., directly between) the source and destination STAs with a
direct link setup (DLS). In certain representative embodiments, the
DLS may use an 802.11e DLS or an 802.11z tunneled DLS (TDLS). A
WLAN using an Independent BSS (IBSS) mode may not have an AP, and
the STAs (e.g., all of the STAs) within or using the IBSS may
communicate directly with each other. The IBSS mode of
communication may sometimes be referred to herein as an "ad-hoc"
mode of communication.
[0062] When using the 802.11ac infrastructure mode of operation or
a similar mode of operations, the AP may transmit a beacon on a
fixed channel, such as a primary channel. The primary channel may
be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set
width via signaling. The primary channel may be the operating
channel of the BSS and may be used by the STAs to establish a
connection with the AP. In certain representative embodiments,
Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
may be implemented, for example in 802.11 systems. For CSMA/CA, the
STAs (e.g., every STA), including the AP, may sense the primary
channel. If the primary channel is sensed/detected and/or
determined to be busy by a particular STA, the particular STA may
back off. One STA (e.g., only one station) may transmit at any
given time in a given BSS.
[0063] High Throughput (HT) STAs may use a 40 MHz wide channel for
communication, for example, via a combination of the primary 20 MHz
channel with an adjacent or nonadjacent 20 MHz channel to form a 40
MHz wide channel.
[0064] Very High Throughput (VHT) STAs may support 20 MHz, 40 MHz,
80 MHz, and/or 160 MHz wide channels. The 40 MHz, and/or 80 MHz,
channels may be formed by combining contiguous 20 MHz channels. A
160 MHz channel may be formed by combining 8 contiguous 20 MHz
channels, or by combining two non-contiguous 80 MHz channels, which
may be referred to as an 80+80 configuration. For the 80+80
configuration, the data, after channel encoding, may be passed
through a segment parser that may divide the data into two streams.
Inverse Fast Fourier Transform (IFFT) processing, and time domain
processing, may be done on each stream separately. The streams may
be mapped on to the two 80 MHz channels, and the data may be
transmitted by a transmitting STA. At the receiver of the receiving
STA, the above described operation for the 80+80 configuration may
be reversed, and the combined data may be sent to the Medium Access
Control (MAC).
[0065] Sub 1 GHz modes of operation are supported by 802.11af and
802.11ah. The channel operating bandwidths, and carriers, are
reduced in 802.11af and 802.11ah relative to those used in 802.11n,
and 802.11ac. 802.11af supports 5 MHz, 10 MHz and 20 MHz bandwidths
in the TV White Space (TVWS) spectrum, and 802.11ah supports 1 MHz,
2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum.
According to a representative embodiment, 802.11ah may support
Meter Type Control/Machine-Type Communications, such as MTC devices
in a macro coverage area. MTC devices may have certain
capabilities, for example, limited capabilities including support
for (e.g., only support for) certain and/or limited bandwidths. The
MTC devices may include a battery with a battery life above a
threshold (e.g., to maintain a very long battery life).
[0066] WLAN systems, which may support multiple channels, and
channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and
802.11ah, include a channel which may be designated as the primary
channel. The primary channel may have a bandwidth equal to the
largest common operating bandwidth supported by all STAs in the
BSS. The bandwidth of the primary channel may be set and/or limited
by a STA, from among all STAs in operating in a BSS, which supports
the smallest bandwidth operating mode. In the example of 802.11ah,
the primary channel may be 1 MHz wide for STAs (e.g., MTC type
devices) that support (e.g., only support) a 1 MHz mode, even if
the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16
MHz, and/or other channel bandwidth operating modes. Carrier
sensing and/or Network Allocation Vector (NAV) settings may depend
on the status of the primary channel. If the primary channel is
busy, for example, due to a STA (which supports only a 1 MHz
operating mode), transmitting to the AP, the entire available
frequency bands may be considered busy even though a majority of
the frequency bands remains idle and may be available.
[0067] In the United States, the available frequency bands, which
may be used by 802.11ah, are from 902 MHz to 928 MHz. In Korea, the
available frequency bands are from 917.5 MHz to 923.5 MHz. In
Japan, the available frequency bands are from 916.5 MHz to 927.5
MHz. The total bandwidth available for 802.11ah is 6 MHz to 26 MHz
depending on the country code.
[0068] FIG. 1D is a system diagram illustrating the RAN 113 and the
CN 115 according to an embodiment. As noted above, the RAN 113 may
employ an NR radio technology to communicate with the WTRUs 102a,
102b, 102c over the air interface 116. The RAN 113 may also be in
communication with the CN 115.
[0069] The RAN 113 may include gNBs 180a, 180b, 180c, though it
will be appreciated that the RAN 113 may include any number of gNBs
while remaining consistent with an embodiment. The gNBs 180a, 180b,
180c may each include one or more transceivers for communicating
with the WTRUs 102a, 102b, 102c over the air interface 116. In one
embodiment, the gNBs 180a, 180b, 180c may implement MIMO
technology. For example, gNBs 180a, 108b may utilize beamforming to
transmit signals to and/or receive signals from the gNBs 180a,
180b, 180c. Thus, the gNB 180a, for example, may use multiple
antennas to transmit wireless signals to, and/or receive wireless
signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b,
180c may implement carrier aggregation technology. For example, the
gNB 180a may transmit multiple component carriers to the WTRU 102a
(not shown). A subset of these component carriers may be on
unlicensed spectrum while the remaining component carriers may be
on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c
may implement Coordinated Multi-Point (CoMP) technology. For
example, WTRU 102a may receive coordinated transmissions from gNB
180a and gNB 180b (and/or gNB 180c).
[0070] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a,
180b, 180c using transmissions associated with a scalable
numerology. For example, the OFDM symbol spacing and/or OFDM
subcarrier spacing may vary for different transmissions, different
cells, and/or different portions of the wireless transmission
spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs
180a, 180b, 180c using subframe or transmission time intervals
(TTIs) of various or scalable lengths (e.g., containing varying
number of OFDM symbols and/or lasting varying lengths of absolute
time).
[0071] The gNBs 180a, 180b, 180c may be configured to communicate
with the WTRUs 102a, 102b, 102c in a standalone configuration
and/or a non-standalone configuration. In the standalone
configuration, WTRUs 102a, 102b, 102c may communicate with gNBs
180a, 180b, 180c without also accessing other RANs (e.g., such as
eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs
102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c
as a mobility anchor point. In the standalone configuration, WTRUs
102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using
signals in an unlicensed band. In a non-standalone configuration
WTRUs 102a, 102b, 102c may communicate with/connect to gNBs 180a,
180b, 180c while also communicating with/connecting to another RAN
such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b,
102c may implement DC principles to communicate with one or more
gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c
substantially simultaneously. In the non-standalone configuration,
eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs
102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional
coverage and/or throughput for servicing WTRUs 102a, 102b,
102c.
[0072] Each of the gNBs 180a, 180b, 180c may be associated with a
particular cell (not shown) and may be configured to handle radio
resource management decisions, handover decisions, scheduling of
users in the UL and/or DL, support of network slicing, dual
connectivity, interworking between NR and E-UTRA, routing of user
plane data towards User Plane Function (UPF) 184a, 184b, routing of
control plane information towards Access and Mobility Management
Function (AMF) 182a, 182b and the like. As shown in FIG. 1D, the
gNBs 180a, 180b, 180c may communicate with one another over an Xn
interface.
[0073] The CN 115 shown in FIG. 1D may include at least one AMF
182a, 182b, at least one UPF 184a, 184b, at least one Session
Management Function (SMF) 183a, 183b, and possibly a Data Network
(DN) 185a, 185b. While each of the foregoing elements are depicted
as part of the CN 115, it will be appreciated that any of these
elements may be owned and/or operated by an entity other than the
CN operator.
[0074] The AMF 182a, 182b may be connected to one or more of the
gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may
serve as a control node. For example, the AMF 182a, 182b may be
responsible for authenticating users of the WTRUs 102a, 102b, 102c,
support for network slicing (e.g., handling of different PDU
sessions with different requirements), selecting a particular SMF
183a, 183b, management of the registration area, termination of NAS
signaling, mobility management, and the like. Network slicing may
be used by the AMF 182a, 182b in order to customize CN support for
WTRUs 102a, 102b, 102c based on the types of services being
utilized WTRUs 102a, 102b, 102c. For example, different network
slices may be established for different use cases such as services
relying on ultra-reliable low latency (URLLC) access, services
relying on enhanced massive mobile broadband (eMBB) access,
services for machine type communication (MTC) access, and/or the
like. The AMF 162 may provide a control plane function for
switching between the RAN 113 and other RANs (not shown) that
employ other radio technologies, such as LTE, LTE-A, LTE-A Pro,
and/or non-3GPP access technologies such as WiFi.
[0075] The SMF 183a, 183b may be connected to an AMF 182a, 182b in
the CN 115 via an N11 interface. The SMF 183a, 183b may also be
connected to a UPF 184a, 184b in the CN 115 via an N4 interface.
The SMF 183a, 183b may select and control the UPF 184a, 184b and
configure the routing of traffic through the UPF 184a, 184b. The
SMF 183a, 183b may perform other functions, such as managing and
allocating UE IP address, managing PDU sessions, controlling policy
enforcement and QoS, providing downlink data notifications, and the
like. A PDU session type may be IP-based, non-IP based,
Ethernet-based, and the like.
[0076] The UPF 184a, 184b may be connected to one or more of the
gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may
provide the WTRUs 102a, 102b, 102c with access to packet-switched
networks, such as the Internet 110, to facilitate communications
between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF
184, 184b may perform other functions, such as routing and
forwarding packets, enforcing user plane policies, supporting
multi-homed PDU sessions, handling user plane QoS, buffering
downlink packets, providing mobility anchoring, and the like.
[0077] The CN 115 may facilitate communications with other
networks. For example, the CN 115 may include, or may communicate
with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server)
that serves as an interface between the CN 115 and the PSTN 108. In
addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with
access to the other networks 112, which may include other wired
and/or wireless networks that are owned and/or operated by other
service providers. In one embodiment, the WTRUs 102a, 102b, 102c
may be connected to a local Data Network (DN) 185a, 185b through
the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and
an N6 interface between the UPF 184a, 184b and the DN 185a,
185b.
[0078] In view of FIGS. 1A-1D, and the corresponding description of
FIGS. 1A-1D, one or more, or all, of the functions described herein
with regard to one or more of: WTRU 102a-d, Base Station 114a-b,
eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b,
UPF 184a-b, SMF 183a-b, DN 185a-b, and/or any other device(s)
described herein, may be performed by one or more emulation devices
(not shown). The emulation devices may be one or more devices
configured to emulate one or more, or all, of the functions
described herein. For example, the emulation devices may be used to
test other devices and/or to simulate network and/or WTRU
functions.
[0079] The emulation devices may be designed to implement one or
more tests of other devices in a lab environment and/or in an
operator network environment. For example, the one or more
emulation devices may perform the one or more, or all, functions
while being fully or partially implemented and/or deployed as part
of a wired and/or wireless communication network in order to test
other devices within the communication network. The one or more
emulation devices may perform the one or more, or all, functions
while being temporarily implemented/deployed as part of a wired
and/or wireless communication network. The emulation device may be
directly coupled to another device for purposes of testing and/or
may performing testing using over-the-air wireless
communications.
[0080] The one or more emulation devices may perform the one or
more, including all, functions while not being implemented/deployed
as part of a wired and/or wireless communication network. For
example, the emulation devices may be utilized in a testing
scenario in a testing laboratory and/or a non-deployed (e.g.,
testing) wired and/or wireless communication network in order to
implement testing of one or more components. The one or more
emulation devices may be test equipment. Direct RF coupling and/or
wireless communications via RF circuitry (e.g., which may include
one or more antennas) may be used by the emulation devices to
transmit and/or receive data.
[0081] In certain representative embodiments, methods, apparatus
and systems may be implemented for service aware multi-resource
radio link monitoring including, for example, associations between
or among one or more Radio Link Monitoring (RLM)-Reference Signal
(RS) (e.g., RLM-RS) resources and one or more Block Error Ratio
(BLER) thresholds, and a generation of IN-SYNC/OUT-OF-SYNC
indication.
[0082] In certain representative embodiments, methods, apparatus
and systems may be implemented for handling reconfiguration of RLM
parameters including one or more BLER thresholds and/or one of more
RLM-RS configurations. For example, the handling of a
reconfiguration may be based on a RLM status of a WTRU, and if
applicable, the configuration of a new RLM process may be
determined based on the status of an ongoing RLM process and/or the
received reconfiguration.
[0083] In certain representative embodiments, methods, apparatus
and systems may be implemented for handling a flexible RLM and/or a
supplemental UL (SUL), including the RLM based triggers to access
the SUL, and/or reconfiguration of RLM aspects when initiating SUL
transmissions, among others.
Radio Link Monitoring in LTE
[0084] FIG. 2 is a diagram illustrating modeling of a
representative RLM procedure 200 in a conventional network (e.g.,
an LTE network). In an LTE network, for example, a WTRU may use
always-on signals such as a Cell-specific Reference Signal (CRS)
for RLM. In LTE, the WTRU estimates the downlink radio link quality
based on the CRS for RLM. The physical (PHY) layer of the WTRU is
configured to periodically assess the radio link quality and
transmits one or more in-sync indications and/or out-of-sync
indications to higher layers based on predefined Q.sub.in and/or
Q.sub.out thresholds. In some examples, the Q.sub.out threshold may
be defined as the level at which the downlink radio link cannot be
reliably received and corresponds to a 10% BLER (Block Error Rate)
of a hypothetical Physical Downlink Control Channel (PDCCH)
transmission. The threshold Q.sub.in may be defined as the level at
which the downlink radio link quality may be significantly more
reliably received than at Q.sub.out and corresponds to a 2% BLER of
a hypothetical PDCCH transmission. Those BLER thresholds and the
definition of hypothetical PDCCH are both fixed/hardcoded in LTE.
When new features (e.g., eMTC, NB-IoT) were supported in some
networks or systems (e.g., later LTE releases), new hypothetical
PDCCH channels were added for the RLM procedure and were specific
to new WTRU categories.
Representative SUL Carrier
[0085] A cell may be configured with at least one additional uplink
(UL) carrier. For example, in NR, a cell may be configured with a
SUL. One motivation for the use of an SUL may be to extend the
coverage of a WTRU operating in or at a high frequency (e.g., a
frequency and/or frequency band above a threshold) such that the
WTRU may perform transmissions on the SUL when configured to a
lower frequency and/or a lower frequency band. For example, the SUL
may be useful when the WTRU moves towards an edge of coverage of a
cell's regular UL carrier (e.g., the RUL). Other possible uses of
the SUL may be for provisioning, for example, of specific services,
higher throughput, and/or increased reliability and may be possible
if the WTRU is configured to perform transmissions on multiple ULs
for the concerned cells concurrently (e.g., near and/or
substantially concurrently, for example in a Time Division
Multiplexed (TDM) fashion).
[0086] For example, the SUL may be implemented and/or modeled in NR
as a cell with a DL carrier associated with two separate UL
carriers. The UL carrier may include and/or consists of a primary
UL (which may be in the high frequency band where the DL carrier is
or is not located), and a SUL (which may be in a lower frequency
band). The terms RUL and SUL are generally used to refer to a
regular UL and supplementary UL, respectively. SUL may be
configured for any type of cell, including (but not limited to) a
primary cell (PCell), a secondary cell (SCell), and/or a Secondary
PCell (SPCell), for example for dual connectivity. The SUL may be
configured for a standalone system, and/or for a cell of a
multi-RAT dual connectivity system.
[0087] The WTRU may perform initial access to a cell using a RUL
and/or a SUL. The SUL's configuration may be broadcasted in minimum
System Information (SI) for a cell. For example, the WTRU may
select the SUL for initial access, if the DL quality of the serving
cell is below a threshold (e.g., a configured, preconfigured,
and/or signaled threshold).
[0088] Different operating modes may be possible, for example, for
the SUL for the WTRU in Radio Resource Control (RRC) Connected
mode. In a first mode of operation, the RRC may configure the WTRU
with multiple ULs (ULs), for example one of which is a RUL with a
typical UL configuration for the concerned cell, and another one
which may minimally include a Sounding Reference Signal (SRS)
configuration (e.g., for a SUL). In the first mode of operation,
the WTRU may use the RUL for control and data transmission (e.g.,
some or all control and data transmissions) in the UL. In lieu of
or in additional to such use of the RUL, the WTRU may transmit the
SRS using resources of the SUL. The RRC reconfiguration may provide
an extended, typical and/or possibly complete, UL configuration for
a different carrier to activate and/or may switch the applicable
active UL carrier for the cell for some or all transmissions.
[0089] In a second mode of operation, the RRC may configure
multiple ULs with an extended, typical and/or possibly complete, UL
configuration. In such a case, the WTRU may have a configuration
(e.g., a sufficient configuration) to perform some or all types of
UL transmissions (e.g., a Physical Uplink Control Channel (PUCCH),
a Physical Uplink Shared Channel (PUSCH) and/or a Physical Random
Access Channel (PRACH), among others) on resources of the concerned
carriers. The WTRU may receive (e.g., subsequently receive) control
signaling (e.g., a MAC CE and/or a downlink control information
(DCI), among others) that may activate and/or may initiate a switch
between the UL configurations.
[0090] In a third mode of operation, the RRC may configure multiple
ULs, and two (or more) UL configurations may be active concurrently
and/or in a time-division fashion. For example, the third mode of
operation may include a restriction such that the WTRU may not be
required to (and/or may not) perform some or all types of UL
transmissions simultaneously (e.g., the WTRU may not be required to
(e.g., and/or may not) transmit a PUSCH for the cell simultaneously
on multiple UL carriers. For example, a restriction may be
configured for the WTRU, e.g., if the WTRU's capability indicate
that simultaneous transmission is not supported (for example, for
the configured frequencies and/or frequency bands).
[0091] In certain representative embodiments, RLM may be
implemented to support diverse set of services. For example, a
predefined BLER threshold may not be suited for all types of
applications. NR may need and or may provide support for diverse
set of services with drastically different QoS, delay and/or
reliability requirements, among others, because different services
may not be impacted equally for a given hypothetical PDCCH error
rate. Based on various use cases, the BLER threshold for a WTRU may
be (e.g., may need to be) customized per service. In some
scenarios, the RLM procedure may be flexible (e.g., flexible
enough) to handle more than one BLER threshold configured
concurrently for a WTRU.
[0092] In certain representative embodiments, RLM may be
implemented to support multi-beams. For example, in the context of
a multi-beam system, (e.g., when beamforming may be used to deliver
both control and data), in the absence of a CRS, the WTRU may need
and/or may use an explicit configuration of one or more RSs to use
for RLM. For example, the WTRU may be configured with more than one
RSs and each RS may be indicative of quality of a beam, a coreset,
and/or a bandwidth part, among others. In certain representative
embodiments (e.g., depending on the use case), the type of RS may
be configurable, (e.g., whether to use a RS associated with a
synchronization block, a Physical Broadcast Channel (PBCH),
Demodulation (DM) RS (e.g., DMRS), among others and/or Channel
State Information (CSI)-RS (e.g., CSI-RS) based RS. Multiple RLM-RS
resources, combined with a customizable BLER threshold may be
addressed by the RLM procedure.
[0093] In certain representative embodiments, methods, procedures
and/or apparatus may be implemented to monitor radio links when
diverse services with different error tolerances and multiple RLM
RS resources are configured for a WTRU.
[0094] In certain representative embodiments, methods, procedures
and/or apparatus may be implemented to handle consequences of a
flexible RLM procedure. For example, one effect of a flexible RLM
procedure, for example may be that the RLM parameters may be
reconfigured from one value to another.
[0095] In certain representative embodiments, methods, procedures
and/or apparatus may be implemented to address: (1) what happens to
the current RLM process status when one or more RLM parameters are
reconfigured; and/or (2) how to handle the reconfiguration of RLM
parameters such that an eventual radio link failure (RLF) may not
be delayed and/or (e.g., at the same time) a premature RLF
declaration may be avoided.
[0096] In certain representative embodiments, methods, procedures
and/or apparatus may be implemented to handle consequences of a SUL
carrier. For example, such an implementation may address how the
RLM framework affect the usage/applicability of SUL carrier and/or
what is the difference in RLM behavior when a supplementary carrier
(e.g., an SUL carrier) is used instead of and/or in addition to a
RUL.
Representative Procedures for a Flexible RLM
[0097] For NR, different RS for RLM may be implemented with
properties (e.g., desirable properties) such as periodic
transmission with short enough periodicity, wideband transmission
relative to the bandwidth of the active bandwidth part, support for
both single beam and multi-beam operations and/or measure of
control channel quality. In NR, two different types of RS (e.g.,
CSI-RS based and Synchronization Signal (SS) block based) may be
supported for RLM. NR may support the configuration of X RLM-RS
resources and the configuration of a single RLM-RS type only to
different RLM-RS resources for a WTRU at any time. The NR design
may support a high degree of spectrum flexibility that may enable
deployment in different frequency bands with varying bandwidths.
For example, the NR system may support diverse set of services with
varying uses/requirements on the Quality of Service (QoS) in terms
of throughput, delay and/or reliability. Different services may not
be impacted equally for a given hypothetical PDCCH error rate.
[0098] For example, to have a flexible RLM that may handle
different types of services with varying tolerance for control
channel quality, in-sync and out-of-sync BLER thresholds may be
implemented to be configurable (e.g., rather than one fixed value).
On condition that a WTRU is configured with one or multiple
services with similar quality of service/error tolerance, the WTRU
may apply one in-sync and out-of-sync BLER threshold (e.g., a
common threshold). The common threshold may be: (1) a default
threshold or; (2) a configured threshold (e.g., an implicitly or
explicitly configured threshold that may be configured by the
network, for example from a list of pre-defined BLER
thresholds).
[0099] On condition that a WTRU is configured with two or more
services (e.g., with significantly varying QoS requirements/error
tolerance), more than one in-sync and/or out-of-sync BLER
thresholds may be configured for the WTRU.
[0100] It is observed/contemplated that different types of service
may have varying degree of tolerance on PDCCH error rate and, for
example, may benefit from a flexible configuration of BLER
thresholds for PDCCH quality assessment.
[0101] In certain representative embodiments, for example, to
address this observation, NR may be implemented to support a
configuration of one or more in-sync BLER and one or more
out-of-sync BLER per WTRU at a time. In certain examples, the WTRU
may be configured with both an eMBB service and URLLC service,
concurrently. The eMBB service may tolerate a higher PDCCH error
rate than, for example the URLLC service. The WTRU may be
configured with two BLER thresholds (e.g., a first BLER threshold
that may be associated with the URLLC service and a second BLER
threshold that may be associated with the URLLC service). For
example, the WTRU may be configured with different actions when
quality of a control channel is or goes below certain thresholds
(e.g., a first action may be associated with the quality of the
control channel being or going below a first BLER threshold and/or
a second action may be associated with the quality of the control
channel being or going below a second BLER threshold). For example,
the WTRU may be configured to transmit a report to the network
(e.g., a network entity) when the quality of control channel is or
goes below the first BLER threshold. The report may indicate the RS
(or RS group) associated with the control channel on which failure
was observed. In another example, the WTRU may be configured to
trigger beam recovery when the quality of the control channel is or
goes below a first BLER threshold. In another example, the WTRU may
be configured to expand a search space or monitor alternate serving
control channels when the quality of the control channel is or goes
below a first BLER threshold. For example, the WTRU may be
configured to determine and/or declare a RLF when the quality of
the control channel is or goes below the second BLER threshold.
[0102] Although first and second BLER thresholds are disclosed
herein, any number of services and thresholds are possible. For
example, one service may have a plurality of thresholds associated
with that service, a plurality of services may have a plurality of
thresholds associated with those services and/or a plurality of
services may have one threshold associated with these services.
[0103] Although first and second BLER thresholds are disclosed
herein, other types of thresholds are possible. For example, the
threshold may include any of: (1) one or more BLER thresholds; (2)
one or more bit error rate (BER) thresholds; and/or (3) one or more
other error rate/ratio thresholds, among others.
[0104] In some examples, the WTRU may be configured to perform RLM
on one or more RLM-RS resources. In some embodiments, the
conditions for generating one or more in-sync indications and/or
one or more out-of-sync indications may be as follows: [0105] (1)
when a WTRU is configured to perform RLM on one or multiple RLM-RS
resources; [0106] (i) Periodic in-sync (IS) may be indicated if the
estimated link quality corresponding to a hypothetical PDCCH BLER
based on at least Y RLM-RS resource among all configured X RLM-RS
resources is above Q_in threshold. [0107] (a) It is contemplated
that Y may be configurable or fixed, and that the value may be a
positive integer (e.g., Y=1), [0108] (ii) It is contemplated that
one or more aperiodic indications may be implemented based on a
beam failure recovery procedure to assist a RLF procedure if a
different RS is used. [0109] (2) Periodic out-of-sync (OOS) is
indicated, [0110] (i) If the estimated link quality corresponding
to a hypothetical PDCCH BLER based on all configured X RLM-RS
resource(s) is below Q_out threshold; [0111] (a) It is contemplated
that the evaluation of OOS may take beam failure recovery procedure
into account.
[0112] In some embodiments, NR may support configuration of
multiple RLM-RS resources for a specific WTRU, where in the RLM-RS
resources (e.g., each RLM-RS resource) may be indicative of the
quality of a control channel. The control channel may be associated
with a CORESET and/or with a beam pair link.
[0113] The generation of one or more in-sync and/or out-of-sync
indications may use `hypothetical PDCCH BLEW` similar to LTE. For
NR, when more than one RLM-RS resource is configured for a WTRU,
consideration of how many of the RLM-RS resources are above or
below the Qin/Qout threshold may be conditions to generate in-sync
and out-of-sync indications. These conditions may be unambiguous
(e.g., straightforward) when only one BLER threshold is configured
for a WTRU. In case of multiple BLER thresholds, any of the
following may be supported for NR:
[0114] (1) a number of (e.g., x) in-sync BLERs and a number of
(e.g., x) out-of-sync BLERs for a hypothetical PDCCH;
[0115] (2) The number of different BLER values x may be in the
range of [1<x.ltoreq.3];
[0116] (3) It is contemplated that one or more in-sync BLER and one
or more out-of-sync BLER may be configured per WTRU at a time;
[0117] (4) It is contemplated that the default may include one
in-sync BLER value and one out-of-sync BLER value are used if not
configured; and/or
[0118] (5) It is contemplated that the values of the BLERs for a
hypothetical PDCCH may correspond to x In-sync and x out-of-sync
thresholds, among others.
[0119] When more than one BLER threshold is configured for a WTRU,
it may not be clear which BLER threshold is to be (e.g., needs to
be) met for the hypothetical PDCCH based on a specific RLM-RS
resource. For example, it may not be clear if one RLM-RS resource
can be associated with more than one BLER threshold. Based on a
linkage between the RLM-RS resource and the configured BLER
thresholds, any of the following comparison procedures may be
possible:
[0120] FIG. 3 is a diagram illustrating a representative comparison
procedure 300 using one configured BLER threshold. Referring to
FIG. 3, for the comparison procedure 300, the PDCCH quality derived
from each of the RLM-RS resources at block 302 may be compared with
one of the configured BLER thresholds at block 304
(1<x.ltoreq.3). In this example, all the RLM-RS resources may be
compared with one BLER threshold at block 306. At 308, the WTRU may
generate an in-sync indication or an out-of-sync indication (e.g.,
for transmitting to higher layers) based on predefined Qin and/or
Qout thresholds (and/or the comparison(s)) in block 306. For
example, BLER measurements associated with the RLM-RS resources 1,
2, 3, . . . X-1, and X may be compared with a configured BLER
threshold at block 306 (in block 304), for example in one or more
of (e.g., in each of) the evaluation periods.
[0121] FIG. 4 is a diagram illustrating a representative comparison
procedure 400 using two or more different BLER thresholds for
comparison to RLM-RS resources. Referring to FIG. 4, in the
representative comparison procedure 400, the PDCCH quality derived
from each the RLM-RS resources at block 402 may be compared with
one of the configured BLER thresholds (1<x.ltoreq.3) at block
404, and different RLM-RS resources may be compared with different
BLER thresholds in block 406, block 408, and/or block 410. This
comparison procedure 400 may be implemented, for example by
grouping the different RS associated with the a CORESET and/or a
group of CORESETs or beam group and comparing against the BLER
specific to that CORESET or CORESET group or beam group. At 412,
the WTRU may generate an in-sync indication or an out-of-sync
indication (e.g., for transmitting to higher layers) based on
predefined Qin and/or Qout thresholds (and/or the comparison(s)) in
block 404. For example, BLER measurements associated with a first
set of RLM-RS resources (e.g., resources 1 and 2) may be compared
with a configured BLER threshold at block 406, measurements
associated with a second set of RLM-RS resources (e.g., resources 3
and 4) may be compared with a configured BLER threshold at block
408, and BLER measurements associated with a third set of RLM-RS
resources (e.g., resources X-1 and X) may be compared with a
configured BLER threshold at block 410.
[0122] Although one or more BLER thresholds are shown to be matched
to RLM-RS resources in a particular manner, other matches are
possible. For example, any number of BLER thresholds may be matched
to any number of RLM-RS resources.
[0123] FIG. 5 is a diagram illustrating a representative comparison
procedure 500. Referring to FIG. 5, for the representative
comparison procedure 500, the PDCCH quality derived from each
RLM-RS resource at block 502 may be compared with more than one of
the configured BLER thresholds (1<x.ltoreq.3) at block 504, and
all of the RLM-RS resources in block 502 may be compared with the
same subset of BLER thresholds (e.g., block 506 or block 508) in
block 504. At 510 and 512, the WTRU may generate an in-sync
indication or an out-of-sync indication (e.g., for transmitting to
higher layers) based on predefined Qin and/or Qout thresholds
(and/or the comparison(s)) in block 504. For example, BLER
measurements associated with the RLM-RS resources (e.g., resources
1, 2, 3 . . . X-1 and X) may be compared with a first configured
BLER threshold at block 506 and a second configured BLER threshold
at block 508.
[0124] Although BLER thresholds are shown to be matched to RLM-RS
resources in a particular manner, other matches are possible. For
example, any number of BLER thresholds (e.g., 1 to N) may be
matched to the RLM-RS resources 1, 2, 3 . . . X-1 and X.
[0125] FIG. 6 is a diagram illustrating a representative comparison
procedure 600. Referring to FIG. 6, for the representative
comparison procedure 600, the PDCCH quality derived from each
RLM-RS resource at block 602 may be compared with more than one of
the configured BLER thresholds (1<x.ltoreq.3) at block 604 and
different RLM-RS resources in block 602 may be compared with
different subset of BLER thresholds in block 604. This comparison
procedure may be implemented, for example, by grouping different
RSs associated with a CORESET or a group of CORESETs or beam group
and comparing against the BLER specific to that CORESET or CORESET
group or beam group. At 612 and 614, the WTRU may generate an
in-sync indication or an out-of-sync indication (e.g., for
transmitting to higher layers) based on predefined Qin and/or Qout
thresholds (and/or the comparison(s)) in block 604. For example,
BLER measurements associated with a first RLM-RS resource (e.g.,
resource 1) may be compared with the configured BLER threshold at
block 606 and the configured BLER threshold at block 608. The BLER
measurements associated with a second RLM-RS resource (e.g.,
resource 2) may be compared with the configured BLER threshold at
block 606 and the configured BLER threshold at block 610. The BLER
measurements associated with a third RLM-RS resource (e.g.,
resource 3) may be compared with the configured BLER threshold at
block 608 and the configured BLER threshold at block 610. The BLER
measurements associated with a fourth RLM-RS resource (e.g.,
resource 4) may be compared with the configured BLER threshold at
block 606 and the configured BLER threshold at block 610.
[0126] Although BLER thresholds are shown to be matched to RLM-RS
resources in a particular manner, other matches are possible. For
example, any number of BLER thresholds may be matched to any number
of RLM-RS resources.
[0127] FIG. 7 is a diagram illustrating a representative comparison
procedure 700. Referring to FIG. 7, for the representative
comparison procedure 700, the PDCCH quality derived from each
RLM-RS resource at block 702 may be compared, at block 704, with
all the configured BLER thresholds (1<x.ltoreq.3) (e.g., block
706, block 708, block 710). At 712, 714, and/or 716, the WTRU may
generate an in-sync indication or an out-of-sync indication (e.g.,
for transmitting to higher layers) based on predefined Qin and/or
Qout thresholds (and/or the comparison(s)) in block 704.
[0128] Although BLER thresholds are shown to be matched to RLM-RS
resources in a particular manner, other matches are possible. For
example, each of the BLER thresholds may be matched to each of the
RLM-RS resources.
[0129] In some embodiments, based on the different comparison
procedures described herein, any of the following observations or
contemplations may be made:
[0130] If more than one BLER threshold is configured (e.g.,
concurrently), procedures/comparisons may be implemented that
clarify and/or determine which BLER thresholds are to be evaluated
for each configured RLM-RS resource.
[0131] If hypothetical PDCCH quality based on each RLM-RS resource
is compared against more than one BLER threshold, it may be
possible that more than one IN-SYNC or OUT-OF-SYNC indication may
be generated.
[0132] In certain representative embodiments, any of following are
made in the case where X RLM-RS resources and multiple BLER
thresholds are configured, (e.g., concurrently) for a WTRU.
[0133] NR may support a configuration of one or more BLER
thresholds for the evaluation of hypothetical PDCCH quality derived
from each RLM-RS resource or RLM-RS resource group.
[0134] NR may support a configuration of an association between
and/or among a RLM-RS resource and one or more corresponding BLER
thresholds, for example to evaluate the hypothetical PDCCH quality
derived from such RLM-RS resources and/or RLM-RS resource
group.
[0135] The association may be implicit or explicit. The association
may be a function of a RLM-RS type (e.g., a CSI-RS and/or SS Block
RS). For example, such an association may be part of RLM-RS
resource configuration.
[0136] It is contemplated how to generate IN-SYNC (IS) and/or
OUT-OF-SYNC (OOS) indications, if more than one BLER threshold is
applied for a hypothetical PDCCH quality derived from each RLM-RS
resource or RLM-RS resource group. In one example, multiple IS
indications and/or OOS indications may be delivered to higher
layers (e.g., RRC) in a reporting instance. In such a case, the
higher layers (e.g., RRC) may differentiate (e.g., may need to
differentiate) the cause of such an indication from lower layers
(e.g., Layer 1). For example, a higher layer (e.g., RRC) may be
configured to perform different actions based on the cause of
IS/OOS indications. In one example, the IS or OOS indication may
carry an additional attribute that may indicate any of the
following: (1) the RLM-RS resource/RLM-RS resource group/RLM-RS
type associated with the indication; (2) the CORESET/CORESET group
associated with the indication; (3) the beam group associated with
the indication; and/or (4) the BLER threshold associated with the
indication, among others.
[0137] In one representative embodiment, when multiple IS or OOS
indications are generated at lower layers, further rules may be
defined to map those multiple indications to a single indication to
higher layers. The examples of such mapping functions may include
any of: (1) if the number of IS indications is higher than or equal
to OOS indications at the lower layers, then IS indications may be
indicated to higher layers, else, an OOS indication may be
generated; (2) if a predefined number of OOS indications is
generated for a preconfigured subset of BLER thresholds, then an
OOS indication may be generated to higher layers; and/or (3) if at
least one OOS indication is generated at lower layers, then an OOS
indication may be indicated to higher layers, among others.
Representative Framework for Flexible RLM
[0138] Referring to FIGS. 3-7, different examples of the
mapping/association function and IS/OOS generation logic are
disclosed. In some embodiments, to support diverse services in
varying deployment scenarios, it may be useful and/or beneficial to
have a flexible RLM framework.
[0139] FIG. 8 is a diagram illustrating a representative RLM
framework 800. In some embodiments, a WTRU may be configured with
two or more RLM-RS resources at block 802, for example to account
for multi-beam scenarios and/or multiple bandwidth parts.
[0140] In some embodiments, a WTRU may be configured with two or
more BLER thresholds at block 806, for example, to determine the
quality of a control channel or performance of a control channel in
a higher level of granularity compared to the conventional
framework. In a conventional (e.g., legacy) framework, the RLM may
track certain states (e.g., only two states) of a control channel
(e.g., whether the control channel works). By configuring more than
one BLER threshold (e.g., in block 810, block 812, and/or block
814), the WTRU may be enabled to evaluate and/or report the
performance of the control channel with a higher granularity. Such
higher level of granularity may, for example enable adaptation of a
radio link to meet specific service uses and/or requirements. In
some implementations or deployments, a higher level of granularity
may, for example, enable activation of a SUL carrier, if available
and/or appropriate.
[0141] In some embodiments, at block 804, a WTRU may be configured
with an association between or among reference signal (e.g.,
RLM-RS) resources (e.g., each reference signal resource) in block
802 and at least one BLER threshold in block 806. The WTRU may use
the association information in block 804 to generate a respective
IS/OOS indication (e.g., one or more IS/OOS indications output from
block 806) for a respective RLM-RS resource.
[0142] In some embodiments, at block 808, a WTRU may be configured
to differentiate the IS/OOS indications generated from lower layers
(or from block 806) based one or more attributes associated with
the IS/OOS indications (e.g., using pre-configured IS/OOS
generation logic). For example, the attributes (e.g., BLER
threshold, CORESET, RLM-RS group, and/or beam group, among others)
may be associated with one or more IS/OOS indications, for example,
IS/OOS indication 816 and/or IS/OOS indication 818.
[0143] In some embodiments, at block 820, a WTRU may be configured
with a mapping for one or more actions and associated rules as to
when to trigger a particular action. For example, a rule may be,
may include, and/or may be based on a function of a number of
IS/OOS indications, and/or a nature attribute associated with such
indications, among others. In certain representative embodiments,
the WTRU may be configured to report to the network (e.g., a
network entity, or a gNB) when the number of consecutive OOS
indications are above a threshold and the attribute associated with
such indications refer to a first BLER threshold. In an example,
the WTRU may be configured to send a report when the quality of the
control channel stays lower than a first BLER threshold for more
than a predefined time period and/or the WTRU may transmit the
report in a RRC message or a MAC CE. For example, the WTRU may be
configured to indicate a current status of a RLM process/procedure
in the report. The report may include a quantized BLER of a
hypothetical control channel. For example, the report may include
the status (e.g., an IS counter and/or an OOS counter) of RSs
configured for RLM. In certain representative embodiments, the
report may indicate the status (e.g., whether running or not) of a
T310 timer implicitly and/or explicitly. In certain representative
embodiments, the WTRU may be configured to switch UL transmissions
to a SUL when the quality of the control channel is below a first
threshold for a predefined time period. For example, the WTRU may
be configured to determine and/or declare RLF when the number of
consecutive OOS indications is above a threshold and/or the
attribute associated with the consecutive OOS indications refer to
a second BLER threshold.
Representative Procedures for Handling RLM Parameter
Reconfiguration
[0144] In certain representative embodiments, processing of a
reconfiguration may be based on a RLM status of a WTRU, and if
applicable, the configuration of the new RLM process may be
determined based on status of the ongoing RLM process and/or the
received reconfiguration.
[0145] A WTRU may be configured to evaluate a status of a current
RLM process according to a context of the received RLM
reconfiguration. For example, a WTRU may determine whether one or
more aspects of the current RLM process influence if and/or how the
received reconfiguration may be applied.
[0146] A WTRU may be configured to apply a reconfiguration (for
example, including a RLM parameter reconfiguration) as a function
of the current status of the RLM process including the status of
counters related to lower layer problem detection and/or status of
one or more RLF timers, among others.
[0147] A WTRU may determine the configuration of the new RLM
process (e.g., the RLM process after reconfiguration) as a function
of the current RLM process status (e.g., the RLM process before a
reconfiguration) and contents of a received reconfiguration.
[0148] For a given RLM reconfiguration, a WTRU may perform
different actions based on the status of the current RLM process. A
WTRU may be configured to reset, continue and/or update the RLM
status according to the received reconfiguration. For example, the
WTRU may perform one or more or combinations of the following
actions upon receiving a reconfiguration:
[0149] (1) Reset RLM Process/Status: [0150] the WTRU may determine
that the status of the current RLM process is not relevant in light
of the received configuration which may update one or more of the
RLM parameters. The WTRU may be configured to reset a RLM process
(including any of: one or more counters, and/or one or more timers,
among others) associated with a stringent radio link quality
requirement when a new configuration is received with a relaxed
radio link quality requirement. This scheme may be beneficial to
avoid premature RLF triggering, if current RLM status is
maintained;
[0151] (2) Continue RLM Process/Status: [0152] the WTRU may
determine that the status of the current RLM process is still
relevant in light of the received configuration which may update
one or more of the RLM parameters. The WTRU may be configured to
continue the RLM process (including any of: the one or more
counters, and/or the one or more timers, among others) associated
with a relaxed radio link quality requirement when a new
configuration is received with stricter radio link quality
requirement. This scheme may be beneficial to avoid delayed RLF
triggering, e.g., to avoid the WTRU being in a poor radio link
condition for extended periods of time, if the current RLM status
is reset;
[0153] (3) Penalty Based Scheme: [0154] the WTRU may be configured
to apply a penalty to the new RLM process based on the status of
the current RLM process. This scheme may be referred to as a hybrid
reset/continue scheme (e.g., the WTRU may reset the current RLM
process, and may define and/or include a mechanism/means to
influence the new RLM process based on a status of the current RLM
process), for example, when radio link issues are/were
observed/determined with the current RLM process. In some
representative embodiments, the WTRU may apply counters/timers for
the new RLM process based on the status of counters/timers for the
current RLM process. For example, the WTRU may apply a shorter T310
timer and/or a smaller N310 value or a larger N311 value for the
new RLM process, when: (1) the T310 was already started/running,
(2) when a remaining time is less than a threshold and/or (3) when
a number of OOS is above a threshold for the current RLM
process;
[0155] (4) Fairness Based Scheme: [0156] the WTRU may ensure that
the new RLM process has a fair chance to determine the radio link
quality according to the configured parameters. For example, the
WTRU may not declare and/or determine a RLF before a minimum time
has elapsed such that the minimum time is at least as long as the
time set and/or required to receive IS indications sufficient to
stop a running RLF timer, if applicable. In one representative
embodiment, the WTRU may be configured to set the T310 according to
the following rule: [0157] Set T310=max(minTime, T310 remaining);
[0158] where minTime=N311*IS periodicity;
[0159] (5) Status of RLM Process Leading to Reconfiguration
Failure: [0160] a WTRU may be configured to determine and/or
declare a reconfiguration failure, if application/execution of a
reconfiguration is or may be detrimental to the RLM procedure. For
example, the WTRU may be configured to apply the reconfiguration
when (e.g., only when) the current RLM status satisfies a
predefined criteria and/or criterion. The WTRU may be configured to
apply a reconfiguration with stricter radio link quality
requirements when (e.g., only when) the current RLM status does not
indicate lower layer problems. For example, the WTRU may be
configured to apply the reconfiguration when T310 is not running.
For example, the WTRU may be configured to apply the
reconfiguration when (e.g., only when) the T310 remaining is above
a threshold. For example, the WTRU may be configured to apply the
reconfiguration when at least N RLM-RS generate IS indications.
Upon failure to apply the reconfiguration, the WTRU may report a
reconfiguration failure to the network. For example, the WTRU may
include a cause for the reconfiguration failure indicating the
status of RLM process, as reason for failure.
[0161] (6) Based on Explicit Indication: [0162] the WTRU may be
explicitly configured in the reconfiguration message with if and/or
how the current RLM process influences the new RLM process. For
example, the indication may signal one or more of the above schemes
for RLM process handling
Representative Configuration Aspects
[0163] Prior to receiving a WTRU specific configuration, a WTRU may
be configured to apply default RLM parameters which may be: (1)
predefined; (2) obtained from minimum SI; and/or (3) obtained from
on-demand SI. The WTRU may be configured to update RLM parameters
via implicit or explicit reconfiguration.
[0164] A WTRU may be configured to handle the reconfiguration
(e.g., by RRC, by MAC and/or by L1 signalling, among others) of one
or more parameters associated with the RLM procedure. In some
examples, the WTRU may implicitly reconfigure one or more RLM
parameters based on one or more preconfigured events. For example,
the reconfigurable RLM parameters may include any one or more of
the following: [0165] (1) one or more BLER thresholds (e.g., which
may be selected from a predefined set of value pairs (IS and OOS
thresholds), BLER thresholds may be changed at different
granularities e.g., a change to a IS threshold only or a change to
a OOS threshold only or a change to both the IS threshold and the
OOS threshold); [0166] (2) a number of RLM-RS resources (e.g., a
configurable number up to X RLM-RS resources); [0167] (3) one or
more specific RLM-RS resources (e.g., among N RLM-RS in the cell, a
subset e.g., X RLM-RSs that may be specific to the WTRU); [0168]
(4) a RLM-RS type (e.g., CSI-RS based and/or SSB based); [0169] (5)
a configuration of the hypothetical PDCCH (e.g., a number of
control symbols, a bandwidth (BW), an aggregation level, a DCI
format/size, and/or a transmit power, among others); [0170] (6) one
or more resources for the RLM-RS transmission (e.g., location
and/or density of the resources in time and/or in the frequency
domain, e.g., a periodicity, a BW, among others); [0171] (7) one or
more filtering parameters (e.g., filter coefficients); [0172] (8)
one or more timers (e.g., T310 and/or T312, or a similar timer,
among others); and/or [0173] (9) one or more counters/values (e.g.,
N310 and/or N311, or a similar counter, among others), among
others.
Representative Triggers for Reconfiguration
[0174] An explicit and/or implicit reconfiguration to RLM
parameters may be triggered for example, due to establishment,
update and/or removal of one or more services which may result in a
change of radio link quality requirement. For example, the WTRU may
be configured with two or more BLER thresholds and/or may switch
from one BLER threshold to another BLER threshold, for example, for
radio link monitoring. In one example, a change of RLM parameters
may be triggered based on a WTRU coverage. For example, the WTRU
may reconfigure the RLM parameters based on any of: (1) one or more
measurements, (2) control channel performance, and/or (3) an input
from beam management, among others. In other examples, a change of
RLM parameters may be triggered, for example due to a change in
characteristics of the RLM-RS at the lower layers, including but
not limited to any of: (1) a number of RS, (2) a bandwidth, (3) a
type of RS, and/or (4) a resource for RS, among others. For
example, the RLM reconfiguration may be triggered due to WTRU
mobility. For example, the WTRU may be configured to perform a RLM
evaluation more frequently. In certain representative embodiments,
the RLM reconfiguration may be triggered, for example, due to a
change in a control channel configuration. For example, when the
control channels are Quasi-Co located (QCLed) with SS block, the
type of RLM-RS may be based on the SS block. For example, when the
control channels are not QCLed with SS block, the type of RLM-RS
may be based on CSI-RS. A reconfiguration of RLM-RS may be
triggered based on a beam management procedure at the lower layers.
In some examples, the WTRU may be configured to determine the
RLM-RS based on the beam management RS. In certain embodiments, the
RLM-RS may be a subset of the beam management RS. In other
embodiments, the RLM-RS may be a superset of the beam management
RS. A RLM-RS may be associated with a bandwidth part. A
reconfiguration of the RLM-RS may be triggered by a change in an
active bandwidth part of a WTRU.
Representative WTRU Procedure to Handle Reconfiguration of BLER
Threshold
[0175] A WTRU may receive a control message to reconfigure from a
first BLER threshold to a second BLER threshold. The WTRU may apply
the reconfiguration based on the current RLM status and the nature
of the BLER threshold change (e.g., a change from a stricter BLER
threshold to a relaxed (e.g., more relaxed) BLER threshold or from
a relaxed BLER threshold to stricter (e.g., more strict) BLER
threshold). In this context, the term `strict` BLER threshold may
refer to a lower BLER threshold (e.g., in a range of about 1% BLER,
for example 0.1% to 10%) e.g., that may require a higher radio link
quality, whereas a `relaxed` BLER threshold may refer to a higher
BLER threshold (e.g., in the range of about 10% BLER, for example
10% or above) e.g., that may accommodate comparatively lower radio
link quality.
[0176] The WTRU may be configured to handle a reconfiguration based
on the current RLM status. Some examples of RLM statuses are set
forth herein. For a RLM process in a normal state (e.g., with no
lower layer issues determined and/or detected), since there are no
lower layer issues, the WTRU may apply reconfiguration of BLER
threshold (e.g., configure lower layers with new threshold,
irrespective of whether the reconfiguration is from a `strict` BLER
threshold to a `relaxed` BLER threshold, or vice versa).
[0177] FIG. 9 is a diagram illustrating a representative RLM
process 900 in which one or more OOS indications are sent from the
lower layer and received by the higher layer, but not enough OOS
indications are received (e.g., the number of OOS indications
received is less than a threshold number, for example, less than
the N310 value) to start a timer 904 (e.g., the timer T310). In an
example, the timer 904 may be configured to start based on
consecutive OOS indications and after expiry may cause a Radio Link
Failure (RLF) to be declared. For example, the timer 904 may be
configured to start after a threshold number (e.g., equal to N310)
of OOS indications and may be stopped after the same or a different
threshold number of IS indications (and/or reset) after expiry and
an RLF is declared.
[0178] Referring to FIG. 9, since the lower layer problems may not
be determined to be critical (e.g., the timer 904 has not started
based on the number of OOS indication(s) received by the higher
layer being below the value N310), the WTRU may be configured to
apply a similar handling for the RLM process in a normal state. In
an example, after a BLER threshold reconfiguration, the WTRU may
reset the RLM process, (e.g., reset the OOS counter, when
reconfiguring from a `strict` BLER threshold to a more `relaxed`
BLER threshold). In this example, reconfiguration of one or more
BLER thresholds may include reconfigure the BLER threshold from a
first BLER threshold 906 to a second BLER threshold 908. In another
example, the WTRU may continue the current RLM process (e.g., does
not clear the OOS counter, when reconfiguring from a first BLER
threshold 906 to a second BLER threshold 908, for example, from the
`relaxed` BLER threshold to the more `strict` BLER threshold).
[0179] FIG. 10 is a diagram illustrating a representative RLM
process 1000 in which the timer 1004 (e.g., timer T310) is running
(e.g., the timer 1004 has started based on the number of OOS
indication(s) received by the higher layer reaching the value N310)
and no IS indications are sent from the lower layer and/or received
by the higher layer. In an example, the timer 1004 may be
configured to start based on consecutive OOS indications and after
expiry may cause an RLF to be declared. For example, the timer 1004
may be configured to start after a threshold number (e.g., equal to
N310) of OOS indications and may expire after a preconfigured
period. For example, the timer 1004 may be configured to expire if
no IS indications are received or if the number of IS indication(s)
received by the higher layer at the WTRU is less than a threshold
value (e.g., the value N311) during the preconfigured period. If
the timer 1004 expires, a RLF may be declared.
[0180] Referring to FIG. 10, since lower layer problems are
detected (e.g., the timer 1004 has started based on the number of
OOS indication(s) received by the higher layer reaching the value
N310), the WTRU may be configured to perform different actions
based on the BLER threshold before and/or after the
reconfiguration. For example, the WTRU may reconfigure the BLER
threshold from a first BLER threshold 1006 to a second BLER
threshold 1008. When reconfiguring from the `relaxed` BLER
threshold to the more `strict` BLER threshold, the WTRU may apply a
penalty to account for periods of poor radio condition which
existed before the reconfiguration. The penalty may be set and/or
realized in terms of a reduced value N310 (e.g., the number of
consecutive OOS indications to start the timer 1004), a higher
value N311 (e.g., the number of consecutive IS indications to stop
the timer 1004), and/or a reduced T310 timer value (e.g., expiry
period), among others. In some cases, upon or after receiving N311
consecutive in-sync (IS) indications, the WTRU may stop the timer
1004 (e.g., the timer T310). In some examples, the WTRU may apply a
fairness criteria/criterion by setting the value of the timer T310
such that the new RLM configuration has a chance to recover the
link before RLF. In certain representative embodiments, the WTRU
may not apply the reconfiguration and may report a reconfiguration
failure: (1) if the T310 timer is running; (2) if the T310 timer is
close to expiry (e.g., when the time remaining for the T310 timer
is below a threshold level), and/or (3) when reconfiguring from the
`relaxed` BLER threshold to the `strict` BLER threshold, among
others. In some cases, when reconfiguring from the `strict` BLER
threshold to the `relaxed` BLER threshold, the WTRU may reset the
RLM process (e.g., the one or more counters/timers), or may reset
the RLM process and apply a penalty (e.g., adjusting one or more
timers and/or counters) to account for poor radio conditions that
existed before the reconfiguration. In some other cases, the WTRU
may continue the RLM process but may apply a reward (e.g.,
adjusting one or more timers and/or counters) to account for a
relaxed BLER condition after the reconfiguration.
[0181] FIG. 11 is a diagram illustrating a representative RLM
process 1100 in which the timer 1104 has started based on the
number of OOS indication(s) received by the higher layer reaching
the value N310 and one or more IS indications are sent from the
lower layer and received by the higher layer during the
preconfigured period (e.g., while the T310 timer is running and
prior to reconfiguration), but not enough IS indications are
received (e.g., less than the value N311) to stop a timer 1104
(e.g., the timer T310). For example, the number of IS indications
received by the higher layer is less than a threshold number, for
example, less than the N311 value, to stop the timer 1104.
[0182] Referring to FIG. 11, the WTRU may be configured to perform
similar actions as for those shown in FIG. 10, as discussed above.
In some embodiments, the WTRU may be configured to perform
additional actions considering one or more IS indications received
when the timer 1104 (e.g., the timer T310) was running. For
example, the WTRU may continue the IS counter when reconfiguring
the BLER from a first BLER threshold 1106 to a second BLER
threshold 1108 (e.g., from the `strict` BLER threshold to the more
`relaxed` threshold). For example, the WTRU may continue the RLM
process but apply a reward (e.g., adjusting one or more timers
and/or counters) to account for relaxed BLER condition after the
reconfiguration. In one embodiment, the WTRU may reset the IS
counter (and/or the timer 1104) when reconfiguring from the more
`relaxed BLER threshold to the more `strict` BLER threshold. For
example, the WTRU may reset the RLM process but apply a penalty
(e.g., adjusting one or more timers and/or counters) to account for
poor radio conditions that existed before the reconfiguration. In
some examples, the WTRU may apply a fairness criteria/criterion by
setting the value of the timer 1104 (e.g., N311) such that a new
RLM configuration or reconfiguration has a chance to recover the
link before RLF.
[0183] Compensation generally refers to one or more
modifications/changes made to timers, counters and/or logic
associated with the determination of an existing RLM status. The
compensation may be based on the existing RLM status after
reconfiguration and/or the RLM status prior to reconfiguration. The
compensation may be a plurality of such compensations and may
include or be in addition to a reset of the RLM process.
Representative WTRU Procedure to Handle Reconfiguration of RLM-RS
Configuration
[0184] A WTRU may receive a control message to reconfigure one or
more aspects related to the RLM-RS configuration. For example, one
result of such reconfiguration may be that the number of RLM-RS
resources monitored by the WTRU may be updated and may include that
any of: [0185] (1) 0, some or all RS resources that generated IS
indications may be removed/released; [0186] (2) 0, some or all RS
resources which generate OOS resources may be removed/released;
and/or [0187] (3) 0 or more new RLM-RS resources may be
added/setup, among others;
Representative Realizations of RLM-RS Reconfigurations
[0188] FIG. 12 is a diagram illustrating examples of RLM-RS
reconfigurations 1200. Referring to FIG. 12, various
reconfigurations may be realized. For example, after the WTRU
determines that the number of RLM-RS resources monitored by the
WTRU may be updated, the WTRU may reconfigure from the current RLM
configuration(s) (e.g., pre-reconfig 1210) to at least a new RLM
configuration (e.g., any of: post-reconfig 1202, 1204, 1206, 1208,
1212, 1214, and/or 1216). For example, the WTRU may reconfigure the
RLM resources monitored based on the status of the pre-reconfig RS
resources. For example: (1) if certain RS resources have one or a
consecutive number of OOS indications (e.g., RS 1 and RS 2) and
other RS resources have one or a consecutive number of IS
indications (e.g., RS 3 and RS 4, the WTRU may reconfigure to
post-reconfig 1202 in which only RS 3 and RS 4 may be monitored
post reconfiguration; (2) post-reconfig 1204 in which RS 3 and RS 4
may be monitored post reconfiguration and monitoring for RS 5 may
be started post reconfiguration; (3) post-reconfig 1206 in which RS
1 and RS 2 may be monitored post reconfiguration; (4) post-reconfig
1208 in which the RS 1 and RS 2 may be monitored post
reconfiguration and monitoring for RS 5 may be started post
reconfiguration; (5) post-reconfig 1212 in which RS 1, RS 2, RS 3
and RS 4 may be monitored post reconfiguration and monitoring for
RS 5 may be started post reconfiguration; (6) post-reconfig 1214 in
which the RS 1 and RS 3 may be monitored post reconfiguration and
monitoring for RS 5 may be started post reconfiguration; and/or (7)
post-reconfig 1216 in which RS 5, RS 6, RS 7, RS 8, and RS 9 may be
started post reconfiguration, among others.
[0189] Although seven different post configurations are shown, any
number of different post configurations are possible and may be
based on the status of the RLM process prior to
reconfiguration.
[0190] In some embodiments, one or more RLM-RS resources
added/setup may belong to a different RLM-RS type. The WTRU may be
monitoring RLM-RS(s) based on Synchronization Signal Block (SSB)
for RLM, and upon receiving a reconfiguration, the WTRU may switch
to RLM-RS(s) based on CSI-RS type or vice versa. In some examples,
the WTRU may be configured to report RLM-RSs that generate OOS
indications and/or RLM-RSs that generate IS indications. The
report, for example, may enable the network (e.g., via a network
entity) to reconfigure RLM-RSs and/or change the RLM-RS type.
[0191] In certain representative embodiments, the RLM-RS
reconfiguration handling may be a function of the current RLM
process status such that the WTRU may update the RLM process, when
one or more RLM-RS are added/removed.
[0192] In one example, a WTRU may be configured to clear the OOS
counter and/or to reset the T310 timer if running, when one, some
or all of the RSs that generate OOS indications are removed after a
RLM-RS reconfiguration. In some examples, the WTRU may apply a
penalty or may apply fairness based on criterion/criteria, if a
physical layer problem and/or a physical layer error occurred
before the RLM-RS reconfiguration.
[0193] In one example, a WTRU may be configured to determine and/or
declare a reconfiguration failure, if application/execution of the
reconfiguration is detrimental (e.g., determined to be detrimental)
to the current RLM process. For example, a WTRU may determine
and/or declare a reconfiguration failure when a certain number of
or all of the RSs that generate IS indication are removed as a
result of the reconfiguration. For example, a WTRU may determine
and/or declare a reconfiguration failure if OOS RSs (e.g., only OOS
RSs) remain after the reconfiguration. The WTRU may report a
reconfiguration failure to the network (e.g., a network entity)
with an appropriate cause value indicating the RLM status. For
example, the WTRU may indicate an identity of the RSs that are IS
and/or an identity of the RSs that are OOS.
[0194] In another example, a WTRU may be configured to clear IS
counter, when one, some or all of the RSs that generate IS are
removed after a RLM-RS reconfiguration. In further examples, a WTRU
may be configured to continue the RLM counters/timers when none of
the existing RSs are removed and/or one or more RLM-RSs are
added.
[0195] In certain representative embodiments, the WTRU may be
configured to continue the RLM counters/timers when one or more RSs
are added while keeping the existing RSs after a reconfiguration.
The WTRU may be configured to reset the RLM counters/timers when
one or more existing RSs are removed after a reconfiguration.
Representative Procedures for Handling RLM and SUL Carriers (for
Example Including Conditions to Determine the Use for and/or Need
for SUL Transmission)
[0196] A WTRU may be configured to access SUL (e.g., by initiate
transmissions on the SUL), for example, when the transmission may
be beneficial/desirable over transmission of the RUL and/or may
complement ongoing transmissions in the RUL. For example, the SUL
may provide enhanced coverage compared to the RUL. For example, the
SUL may include or be a low frequency carrier (e.g., below a
threshold frequency) or a high frequency carrier (e.g., above a
threshold frequency) and/or may include enhanced beamforming
capability. For example, the SUL access may be based on: (1) WTRU
autonomous procedures; (2) implicitly signalling; and/or (3) upon
reception of explicit signalling, among others.
[0197] A WTRU may be configured to initiate transmissions on the
SUL based on one or more preconfigured events. The preconfigured
events may correspond to DL quality below a threshold and/or one or
more metrics associated with a control channel performance (e.g.,
BLER threshold or the likes) which may be indicative of WTRU
entering a coverage region where UL path loss exceeds a threshold,
for example, resulting in UL RLF. For example, the WTRU may be
configured with a SUL and access to the SUL may be applicable when
any of the following conditions are satisfied: [0198] (1) an
implicit determination of UL path loss exceeding a threshold. For
example, using a DL measurement that indicate cell quality below a
threshold such that the cell quality may be derived based on N best
beams. One realization may be based on measurement event A2 or the
likes, and the WTRU may be configured with a specific action on the
SUL when the A2 measurement event is satisfied. [0199] (2) a
characteristic associated with DL beams, e.g., a type of RS
associated with the DL control channel. For example, the WTRU may
determine SUL transmissions are applicable when DL control beams
are QCLed with SS Block. [0200] (3) an explicit configuration of a
subset of RSs, measurements of which may determine the use and/or
need for a SUL. For example, the WTRU may be explicitly configured
with a subset of RSs associated with wide beams and/or beams
associated with a subset of TRPs. If the RS Received Power (RSRP),
RS Received Quality (RSRQ) and/or Signal to Interference plus Noise
Ratio (SINR) associated with the subset of RS is below a threshold,
the WTRU may determine that SUL access may be used and/or needed.
[0201] (4) a characteristic associated with the DL control channel.
For example, the WTRU may determine that SUL access may be used
and/or needed when more than N DCIs are received with an
aggregation level of x and higher. For example, the WTRU may
determine that the SUL access may be used and/or needed when a DCI
is received on a predefined CORESET. [0202] (5) criterion/criteria
to access the SUL may be a function of the RLM status. For example,
the WTRU may determine that the SUL access may be used and/or
needed when lower layer problems/errors are determined and/or
detected. For example, the WTRU may determine that the SUL access
may be used and/or needed when the T310 timer is running, the T310
timer is running for longer than a predefined time and/or the T310
timer is close to expiry. For example, the WTRU may determine that
the SUL access may be used and/or needed when the radio link
quality is worse than a first BLER threshold. For example, the WTRU
may determine that the SUL access may be used and/or needed when a
number of OOS indications is above a threshold. [0203] (6)
criterion/criteria to access the SUL may be a function of beam
management status. [0204] (i) In one example, the WTRU may be
configured to access the SUL upon a loss of a beam paired link in a
RUL. For example, the WTRU may detect a loss of a beam paired link
during a beam management procedure. For example, the WTRU may be
configured to access the SUL when the WTRU cannot determine that a
UL beam in the RUL is valid/usable (e.g., when a predefined time
after the UL beam was confirmed to be valid/usable expires). For
example, the WTRU may be configured to access the SUL when a beam
recovery procedure fails, for example, when the WTRU cannot
identify a candidate beam and/or when a candidate beam is below
threshold. [0205] (ii) In another example, the WTRU may be
configured to access the SUL when an UL beam is not available in
the RUL, for example after a period of inactivity during which a UL
beam pair is not maintained, for example, when the DL beam changes
during a period of inactivity. Upon arrival of the UL control
and/or data, the WTRU may be configured to select a UL carrier
based on an activity level and characteristics of the UL data. For
example, the WTRU may be configured to perform transmissions in the
SUL for a control procedure (e.g., a SI request and/or a RAN area
update in an INACTIVE state, among others) and/or may transfer
small UL data (e.g., with a size below a preconfigured threshold).
In some examples, the WTRU may be explicitly configured in a DL
message (e.g., in a paging message) as to whether a corresponding
UL message (e.g., a paging response) is to be and/or needs to be
transmitted in the SUL or the RUL. In certain representative
embodiments, the WTRU may be configured to transmit UL control
and/or data after a period of inactivity, if there is a change in
the DL beam. [0206] (7) status of time alignment timer associated
with the RUL and the SUL. For example, when the time alignment
timer associated with a RUL carrier is expired, the WTRU may
determine that the SUL access may be appropriate and/or required.
For example, the WTRU may make such assumptions (for example that
use of a SUL carrier is possible) when (e.g., only when) time
alignment timer associated with the SUL is running (e.g., still
running and valid). [0207] (8) upon receiving a PUCCH/SRS release
from lower layers. For example, upon receiving a lower layer
indication that PUCCH/SRS associated with a RUL be released, the
WTRU may determine that SUL access may be appropriate and/or
needed. [0208] (9) a condition based on triggers local to the WTRU.
For example, the WTRU may access a SUL upon determining that a RUL
is not usable based on an implementation constraint. For example,
upon determining and/or detecting (e.g., using proximity sensor,
external information and/or any other sensor, among others) that
the beamforming capability is temporarily hindered, (e.g., due to a
human body, a hand holding the WTRU/device, and/or a head
blockage), the WTRU may switch to a SUL since beamforming gain on a
RUL may be reduced. In some examples, the WTRU may determine that
the RUL may not be usable due to in-device-coexistence constraints.
The WTRU may be configured to report an occurrence of a temporary
restriction of a RUL access. For example, the WTRU may report to
the network (e.g., a network entity) when the temporary restriction
is no longer applicable. [0209] (10) When a number of HARQ
retransmissions is above a threshold.
[0210] In certain representative embodiments, the WTRU may switch
to SUL transmission triggering one or more actions from WTRU. The
WTRU may perform one or more actions upon initiating transmissions
in the SUL and/or when criterion/criteria to access the SUL is
satisfied. For example, a switch of the UL between a RUL and a SUL
contemplates (e.g., may imply) that the WTRU may assume different
characteristics for the DL transmissions. For example, a switch to
the SUL may indicate that the WTRU is closer to a cell edge and may
trigger one or more actions at the WTRU. For example, upon
initiating transmissions on the SUL and/or when the
criterion/criteria to access the SUL is satisfied, the WTRU may:
[0211] (1) apply a reconfiguration of one or more aspects
associated with control channel reception. [0212] (i) For example,
the WTRU may monitor PDCCH candidates in a higher aggregation
level. For example, the WTRU may monitor different DCI format
applicable for UL grants on the SUL. [0213] (ii) For example, the
WTRU may monitor a specific subset of control channels. In one
example, the WTRU may start to monitor a DCI in a control channel
associated with narrow beams and/or beams that provide enhanced
coverage. [0214] (2) apply a reconfiguration of one or more aspects
associated with radio link monitoring. [0215] (i) For example, the
WTRU may change to a different hypothetical PDCCH configuration for
determining a BLER to generate IS/OOS indications for the RLM. For
example, an aggregation level of the hypothetical PDCCH may be
switched to a higher level. For example, a size of a DCI message
associated with the hypothetical PDCCH configuration may be
different for a SUL and a RUL. [0216] (ii) For example, the WTRU
may use a different (e.g., lower) BLER threshold when SUL access is
initiated. [0217] (iii) For example, the WTRU may monitor a
preconfigured subset of RSs for RLM. In one example, a subset may
correspond to narrow beams and/or beams that provide enhanced
coverage. [0218] (iv) For example, the WTRU may be configured to
report a status of the RLM process upon switching to the SUL. For
example, the report may include a quantized BLER of a hypothetical
control channel. For example, the report may include a status
(e.g., an IS counter and/or an OOS counter) of RSs configured for
RLM. For example, the report may indicate the status (e.g., whether
running or not) of the T310 timer, explicitly and/or implicitly
(e.g., the report triggered, when the T310 timer is started when
the SUL transmission is ongoing or the T310 timer is ongoing when
SUL access is started). [0219] (3) apply a reconfiguration of one
or more aspects related to measurements. [0220] (i) For example,
the WTRU may trigger measurement of a specific subset of RSs. In
one example, the subset may be associated with narrow beams or
beams that provide enhanced coverage. [0221] (ii) For example, the
WTRU may trigger neighbour measurements, when initial transmission
on a SUL is initiated and/or when one or more conditions to access
the SUL are satisfied. For example, the WTRU may use a combination
of s-measure being below a threshold and a SUL transmission trigger
to start neighbour measurements. [0222] (iii) For example, the WTRU
may trigger transmission of a measurement report related to a
handover event. For example, the WTRU may transmit a measurement
report for one or more candidate cells whose time to trigger is
running [0223] (4) apply a reconfiguration related to mobility
aspect [0224] (i) For example, the WTRU may be configured with
access of a SUL as one of the conditions to apply a mobility
reconfiguration (e.g., a conditional reconfiguration). For example,
the conditions may include the quality of the neighbour measurement
being above a threshold, alone or in combination with other
conditions. For example, the conditions may include that a T312
timer is running [0225] (5) suspend one or more UL transmissions on
a RUL [0226] (i) For example, the WTRU may be configured to suspend
UL transmissions in a RUL, for example: (1) with exception of SRS
transmissions. For example, upon initiating SUL access, the WTRU
may clear outstanding grants applicable for the RUL. For example,
upon initiating SUL access, the WTRU may clear outstanding Power
Headroom Reports (PHRs) applicable for a RUL. [0227] (6) One or
more of the above reconfiguration may refer to implicit and/or
explicit reconfiguration.
[0228] The contents of each of the following are incorporated by
reference herein: (1) 3GPP RAN1 chairman notes from RAN1#89AH; and
(2) 3GPP RAN1 chairman notes from RAN1#90.
[0229] FIG. 13 is a diagram illustrating a method of an RLM
procedure according to embodiments discussed herein.
[0230] According to various embodiments, a WTRU may include a
transmitter, a receiver (and/or transceiver), and a processor
performing a method 1300 illustrated in FIG. 13. Referring to FIG.
13, at operation 1302, a WTRU may map one or more RLM-RS resources
to at least one BLER threshold of a plurality of BLER thresholds.
At operation 1304, for each respective RLM resource that is mapped,
the WTRU may determine a BLER of the respective RLM-RS resource at
operation 1306. At operation 1308, the WTRU may compare the
determined BLER of the respective RLM-RS resource with the at least
one mapped BLER threshold associated with the respective RLM-RS
resource. At operation 1310, the WTRU may generate, based on one or
more of the comparisons, a set of in-sync indications and/or a set
of out-of-sync indications. At operation 1312, the WTRU may
indicate one or more attributes associated with the set of in-sync
indications and/or the set of out-of-sync indications.
[0231] According to various embodiments, a respective BLER
threshold of the plurality of BLER threshold may be associated with
a service type. For example, the service type may be any of:
ultra-reliable low latency (URLLC), enhanced massive mobile
broadband (eMBB), and/or enhanced machine-type communication
(eMTC). According to various embodiments, the WTRU may obtain a
type of service associated with a communication, and may select the
at least one BLER threshold in accordance with the obtained type of
service.
[0232] According to various embodiments, the one or more attributes
may be or may indicate any of: (1) a respective RLM-RS resource, an
RLM-RS resource group, or an RLM-RS type associated with the set of
in-sync indications and/or the set of out-of-sync indications, (2)
a CORESET or a CORESET group associated with the set of in-sync
indications and/or the set of out-of-sync indications, (3) a beam
group associated with the set of in-sync indications and/or the set
of out-of-sync indications, and/or (4) a respective BLER threshold
associated with the set of in-sync indications and/or the set of
out-of-sync indications.
[0233] According to various embodiments, the WTRU may be configured
to map each respective RLM-RS resource to one BLER threshold of the
plurality of BLER thresholds. According to various embodiments, the
WTRU may be configured to compare the determined BLER of each
respective RLM-RS resource to the at least one mapped BLER
threshold.
[0234] According to various embodiments, the WTRU may group two or
more of the RLM-RS resources that are associated with any of: (1)
one CORESET; (2) a group of CORESETs; and/or (3) a beam group.
According to various embodiments, the WTRU may determine a
composite BLER specific to the grouped RLM-RS resources based on
the determined BLER, and compare the composite BLER specific to the
grouped RLM-RS resources with one of the at least one mapped BLER
threshold.
[0235] According to various embodiments, the WTRU may be configured
to generate the set of one or more in-sync indications and/or the
set of one or more out-of-sync indications for: (1) each comparison
of the determined BLER of the respective RLM-RS resource with the
at least one mapped BLER threshold associated with the respective
RLM-RS resource, or (2) a set of comparisons associated with the
grouped RLM-RS resources.
[0236] According to various embodiments, the WTRU may be configured
to generate the set of one or more in-sync indications and/or the
set of one or more out-of-sync indications associated with: (1) the
at least one mapped BLER threshold; (2) a subset of the at least
one mapped BLER threshold; or (3) for each of the at least one
mapped BLER threshold.
[0237] According to various embodiments, the WTRU may be configured
to map each RLM-RS resource to two or more BLER thresholds of the
plurality of BLER thresholds. According to embodiments, the WTRU
may be configured to compare the determined BLER associated with
each respective RLM-RS resource or a group of RLM-RS resources to
the two or more mapped BLER thresholds.
[0238] According to embodiments, the WTRU may be configured to
generate a composite set of in-sync indications and/or out-of-sync
indications for each of the at least one mapped BLER thresholds or
N composite sets of in-sync indications and/or out-of-sync
indications for M BLER thresholds, where N and M are positive
integer values, and N is less than or equal to M.
[0239] According to various embodiments, the WTRU may be configured
to determine, prior to the mapping, a first set of BLER thresholds
of the plurality of BLER thresholds to be mapped with the one or
more RLM-RS resources.
[0240] According to various embodiments, the WTRU may be configured
to determine, after the mapping, that a second set of BLER
thresholds of the plurality of BLER thresholds is to be mapped with
the one or more RLM-RS resources and/or other RLM-RS resources.
According to embodiments, the WTRU may modify a RLM configuration
from a mapping of the one or more RLM-RS resources with the first
set of BLER thresholds to a different mapping of the one or more
RLM-RS resources and/or the other RLM-RS resources with the second
set of BLER thresholds or may remap the one or more RLM-RS
resources and/or the other RLM-RS resources with the second set of
BLER thresholds. According to various embodiments, the WTRU may be
configured to compare the determined BLER of the respective RLM-RS
resources with the second set of modified or remapped BLER
thresholds. According to embodiments, the second set of BLER
thresholds is same as or different from the first set of BLER
thresholds.
[0241] According to various embodiments, the WTRU may reconfigure
at least one BLER threshold of the plurality of BLER thresholds
from a first BLER threshold to a second BLER threshold. According
to various embodiments, after the reconfiguring, the one or more
attributes associated with the set of in-sync indications and/or
the set of out-of-sync indications may be based on a configuration
of an RLM process prior to and after the reconfiguration.
[0242] According to various embodiments, the WTRU may, in one or
more evaluation periods after the reconfiguration, provide: (1) a
first type of compensation associated with the set of out-of-sync
indications prior to the reconfiguration on condition that the
reconfiguration of the at least one BLER threshold of the plurality
of BLER thresholds transitioned from a more relaxed BLER threshold
to a stricter BLER threshold, or (2) a second type of compensation
on condition that the reconfiguration of the at least one BLER
threshold of the plurality of BLER thresholds transitioned from a
stricter BLER threshold to a more relaxed BLER threshold. According
to various embodiments, the first type of compensation and the
second type of compensation are time-based compensations to extend
or shorten a timer.
[0243] According to various embodiments, the WTRU may determine the
one or more attributes after the reconfiguration using
compensation, and the one or more attributes may be determined by
determining the set of in-sync indications and/or the set of
out-of-sync indications after the reconfiguration and a penalty or
a reward associated with the set of in-sync indications and/or
out-of-sync indications prior to the reconfiguration. According to
various embodiments, the WTRU may select the penalty based on the
set of out-of-sync indications prior to reconfiguration for the
compensation of the set of out-of-sync indications after
reconfiguration on condition that the at least one BLER threshold
of the plurality of BLER thresholds transitioned from a relaxed
BLER threshold to a stricter BLER threshold. According to various
embodiments, the WTRU may select the reward based on the set of
out-of-sync indications prior to reconfiguration for the
compensation of the set of out-of-sync indications after
reconfiguration on condition that the at least one BLER threshold
of the plurality of BLER thresholds transitioned from a strict BLER
threshold to a more relaxed BLER threshold. According to
embodiments, the WTRU may select the reward based on the set of
in-sync indications prior to reconfiguration for the compensation
of the set of in-sync indications after reconfiguration on
condition that the at least one BLER threshold of the plurality of
BLER thresholds transitioned from a relaxed BLER threshold to a
stricter BLER threshold. According to embodiments, the WTRU may
select the penalty based on the set of in-sync indications prior to
reconfiguration for the compensation of the set of in-sync
indications after reconfiguration on condition that the at least
one BLER threshold of the plurality of BLER thresholds transitioned
from a strict BLER threshold to a more relaxed BLER threshold.
[0244] FIG. 14 is a diagram illustrating a method of an RRC
reconfiguration for an RLM procedure according to embodiments
discussed herein.
[0245] According to various embodiments, a WTRU may include a
transmitter, a receiver (and/or transceiver), and a processor
performing a method 1400 implemented by a WTRU to transition from a
first RRC configuration to a second RRC configuration, as a RCC
reconfiguration illustrated in FIG. 14. Referring to FIG. 14, in an
example, at operation 1402, a WTRU may receive the second RRC
configuration indicating a first set of BLER thresholds that is
different from one or more BLER thresholds indicated in the first
RRC configuration. At operation 1404, the WTRU may generate, based
on the first set of BLER thresholds after reception of the second
RRC configuration, one or more in-sync indications and/or one or
more out-of-sync indications. At operation 1406, the WTRU may
indicate one or more attributes associated with the one or more
in-sync indications and/or the one or more out-of-sync
indications.
[0246] According to various embodiments, the WTRU may indicate the
one or more attributes associated with the one or more in-sync
indications and/or the one or more out-of-sync indications by
compensating, by the WTRU based on at least an existing RLM status,
for a difference between the first RRC configuration and the second
RRC configuration as part of the transition from the first RRC
configuration to the second RRC configuration. According to various
embodiments, the compensation(s) for the difference between the
first RRC configuration and the second RRC configuration includes
any of: (1) the WTRU being configured to apply a penalty to
counters and/or timers to account for differences in an ongoing RLM
process; (2) the WTRU being configured to apply fairness to avoid a
premature radio link failure (RLF); (3) the WTRU being configured
to update an expiry of a timer to avoid an RLF until after expiry
of the updated timer; and/or (4) the WTRU being configured to
continue performing an RLM process or to reset an RLM process
selectively, based on one or more rules to avoid the premature RLF
or a delayed RLF.
[0247] FIG. 15 is a diagram illustrating another method of an RLM
procedure according to embodiments discussed herein.
[0248] According to various embodiments, a WTRU may include a
transmitter, a receiver (and/or transceiver), and a processor
performing a method 1500 for RLM as illustrated in FIG. 15.
Referring to FIG. 15, in an example, at operation 1502, a WTRU may
receive a configuration to update one or more of the RLM
parameters. At operation 1504, the WTRU may determine an action to
take based on a status of a current RLM process and the received
configuration. At operation 1506, the WTRU may take the action with
respect to the current RLM process based on the determination.
[0249] According to various embodiments, the action mentioned above
may include any of: (1) resetting the current RLM process; (2)
resetting the current RLM status; (3) continuing the current RLM
process; (4) continuing the current RLM status; (5) applying a
penalty to a new RLM process; (5) configuring a new RLM process and
delaying a determination of radio link quality for a period; (6)
declaring a radio link failure on condition that a reconfiguration
is detrimental to an RLM procedure; and/or (7) determining an
explicit indication in a reconfiguration message and taking the
action associated with the explicit indication.
[0250] According to various embodiments, the WTRU may be configured
to reset the current RLM process on a condition that a current
configuration of RLM process is associated with a stringent radio
link quality requirement and the received configuration is
associated with a more relaxed radio link quality requirement.
[0251] According to various embodiments, the WTRU may be configured
to continue the current RLM process on condition that the current
configuration of RLM process is associated with a relaxed radio
link quality requirement and the received configuration is
associated with a more stringent radio link quality
requirement.
[0252] According to various embodiments, the WTRU may be configured
to apply a penalty to the new RLM process. For example, the WTRU
may be configured to apply any of: (1) a shorter T310 timer than
nominal; (2) a smaller N310 value and/or a larger N311 value than
nominal for the new RLM process, on a condition that any of: (i)
the T310 timer was already running; (ii) a remaining time is less
than a threshold; and/or (iii) a number of out-of-sync indications
is above a threshold for the current RLM process.
[0253] According to various embodiments, the WTRU may be configured
to delay the determination of radio link quality for the period.
For example, the WTRU may be configured not to declare a radio link
failure prior to a minimum time having elapsed. In an example, the
minimum time is at least as long as a time to receive in-sync
indications sufficient to stop a running radio link failure
timer.
[0254] FIG. 16 is a diagram illustrating a method of RLM and
supplementary uplink (SUL) transmissions according to embodiments
discussed herein.
[0255] According to various embodiments, a WTRU may include a
transmitter, a receiver (and/or transceiver), and a processor
performing a method 1600 for RLM as illustrated in FIG. 16.
Referring to FIG. 16, in an example, at operation 1602, a WTRU may
identify a RLM status. At operation 1604, the WTRU may initiate a
transmission on a supplementary uplink (SUL) carrier based on one
or more conditions associated with the identified RLM status. At
operation 1606, the WTRU may reconfigure one or more current
configurations of the WTRU after the initiation of the transmission
on the SUL carrier.
[0256] According to various embodiments, the one or more conditions
may include any of: (1) a timer: (i) running; (ii) running for
longer than a predefined period; and/or (iii) expiring; (2) a radio
link quality being worse than a BLER threshold; and/or (3) a number
of out-of-sync indications being above a threshold.
[0257] According to various embodiments, the WTRU may reconfigure
the one or more current configurations by any of the following
process: (1) updating a preconfigured hypothetical control channel
configuration; (2) updating a BLER threshold for RLM; (3)
triggering measurements of one or more neighbor cells; (4)
transmitting a measurement report associated with a handover;
and/or (5) triggering a report of a current RLM status or a status
of a RLM process.
[0258] FIG. 17 is a diagram illustrating another method of RLM and
SUL transmissions according to embodiments discussed herein.
[0259] According to various embodiments, a WTRU may include a
transmitter, a receiver (and/or transceiver), and a processor
performing a method 1700 for RLM as illustrated in FIG. 17.
Referring to FIG. 17, in an example, at operation 1702, a WTRU may
determine that one or more conditions are satisfied. At operation
1704, the WTRU may initiate a transmission on an SUL carrier based
on the determination. At operation 1706, the WTRU may reconfigure
one or more current configurations of the WTRU after the initiation
of the transmission on the SUL carrier.
[0260] According to various embodiments, the one or more conditions
may include any of: (1) an uplink path loss exceeding a threshold;
(2) a certain type of reference signal associated with a downlink
control channel being identified; (3) a measurement of a subset of
reference signals being below a threshold; (4) more than a first
number of downlink control information (DCI) being received having
an aggregation level being equal or higher than a predetermined
level; (5) a DCI being received on a predefined CORESET; (6) one or
more criteria to access the SUL carrier being a function of a RLM
status and being satisfied; (7) one or more criteria to access the
SUL carrier being a function of a beam management status and being
satisfied; (8) when a time alignment timer associated with a
regular uplink (RUL) carrier being expired; (9) receiving an
indication from a lower layer indicating that a Physical Uplink
Control Channel (PUCCH) or a Sounding Reference Signal (SRS)
associated with RUL being released; and/or (10) when a number of
hybrid automatic repeat request (HARQ) retransmissions being above
a threshold.
[0261] According to various embodiments, the WTRU may reconfigure
the one or more current configurations by any of the following
process: (1) reconfiguring to monitor one or more Physical Downlink
Control Channel (PDCCH) candidates in a higher aggregation level
compared with a current configured aggregation level; (2)
reconfiguring to monitor a specific subset of control channels; (3)
adjusting to a different aggregation level from a current
aggregation level of a PDCCH; (4) using a different BLER threshold
compared with a current BLER threshold; (5) reconfiguring to
monitor a preconfigured subset of reference signals for RLM; (6)
reporting a status of a RLM process; (7) triggering measurements of
one or more neighbor cells; (8) transmitting a measurement report
associated with a handover; and/or (9) triggering a report of a
current RLM status or a status of a RLM process.
[0262] According to various embodiments, the WTRU may reconfigure
the one or more current configurations by applying a mobility
reconfiguration. According to various embodiments, the WTRU may
reconfigure the one or more current configurations by suspending or
delaying uplink transmissions on a RUL carrier.
[0263] According to various embodiments, the WTRU may determine
that one or more conditions are satisfied, and each of the one or
more conditions are associated with a respective RLM status. In
addition, the WTRU may determine that at least one criteria to
access an SUL carrier is satisfied. The WTRU may reconfigure one or
more current RLM configurations of the WTRU, based on the
determination of the one or more conditions and the at least one
criteria are satisfied. Although features and elements are
described above in particular combinations, one of ordinary skill
in the art will appreciate that each feature or element can be used
alone or in any combination with the other features and elements.
In addition, the methods described herein may be implemented in a
computer program, software, or firmware incorporated in a computer
readable medium for execution by a computer or processor. Examples
of non-transitory computer-readable storage media include, but are
not limited to, a read only memory (ROM), random access memory
(RAM), a register, cache memory, semiconductor memory devices,
magnetic media such as internal hard disks and removable disks,
magneto-optical media, and optical media such as CD-ROM disks, and
digital versatile disks (DVDs). A processor in association with
software may be used to implement a radio frequency transceiver for
use in a WTRU 102, UE, terminal, base station, RNC, or any host
computer.
[0264] Moreover, in the embodiments described above, processing
platforms, computing systems, controllers, and other devices
containing processors are noted. These devices may contain at least
one Central Processing Unit ("CPU") and memory. In accordance with
the practices of persons skilled in the art of computer
programming, reference to acts and symbolic representations of
operations or instructions may be performed by the various CPUs and
memories. Such acts and operations or instructions may be referred
to as being "executed," "computer executed" or "CPU executed."
[0265] One of ordinary skill in the art will appreciate that the
acts and symbolically represented operations or instructions
include the manipulation of electrical signals by the CPU. An
electrical system represents data bits that can cause a resulting
transformation or reduction of the electrical signals and the
maintenance of data bits at memory locations in a memory system to
thereby reconfigure or otherwise alter the CPU's operation, as well
as other processing of signals. The memory locations where data
bits are maintained are physical locations that have particular
electrical, magnetic, optical, or organic properties corresponding
to or representative of the data bits. It should be understood that
the representative embodiments are not limited to the
above-mentioned platforms or CPUs and that other platforms and CPUs
may support the provided methods.
[0266] The data bits may also be maintained on a computer readable
medium including magnetic disks, optical disks, and any other
volatile (e.g., Random Access Memory ("RAM")) or non-volatile
(e.g., Read-Only Memory ("ROM")) mass storage system readable by
the CPU. The computer readable medium may include cooperating or
interconnected computer readable medium, which exist exclusively on
the processing system or are distributed among multiple
interconnected processing systems that may be local or remote to
the processing system. It is understood that the representative
embodiments are not limited to the above-mentioned memories and
that other platforms and memories may support the described
methods.
[0267] In an illustrative embodiment, any of the operations,
processes, etc. described herein may be implemented as
computer-readable instructions stored on a computer-readable
medium. The computer-readable instructions may be executed by a
processor of a mobile unit, a network element, and/or any other
computing device.
[0268] There is little distinction left between hardware and
software implementations of aspects of systems. The use of hardware
or software is generally (but not always, in that in certain
contexts the choice between hardware and software may become
significant) a design choice representing cost vs. efficiency
tradeoffs. There may be various vehicles by which processes and/or
systems and/or other technologies described herein may be affected
(e.g., hardware, software, and/or firmware), and the preferred
vehicle may vary with the context in which the processes and/or
systems and/or other technologies are deployed. For example, if an
implementer determines that speed and accuracy are paramount, the
implementer may opt for a mainly hardware and/or firmware vehicle.
If flexibility is paramount, the implementer may opt for a mainly
software implementation. Alternatively, the implementer may opt for
some combination of hardware, software, and/or firmware.
[0269] The foregoing detailed description has set forth various
embodiments of the devices and/or processes via the use of block
diagrams, flowcharts, and/or examples. Insofar as such block
diagrams, flowcharts, and/or examples contain one or more functions
and/or operations, it will be understood by those within the art
that each function and/or operation within such block diagrams,
flowcharts, or examples may be implemented, individually and/or
collectively, by a wide range of hardware, software, firmware, or
virtually any combination thereof. Suitable processors include, by
way of example, a general purpose processor, a special purpose
processor, a conventional processor, a digital signal processor
(DSP), a plurality of microprocessors, one or more microprocessors
in association with a DSP core, a controller, a microcontroller,
Application Specific Integrated Circuits (ASICs), Application
Specific Standard Products (ASSPs); Field Programmable Gate Arrays
(FPGAs) circuits, any other type of integrated circuit (IC), and/or
a state machine.
[0270] Although features and elements are provided above in
particular combinations, one of ordinary skill in the art will
appreciate that each feature or element can be used alone or in any
combination with the other features and elements. The present
disclosure is not to be limited in terms of the particular
embodiments described in this application, which are intended as
illustrations of various aspects. Many modifications and variations
may be made without departing from its spirit and scope, as will be
apparent to those skilled in the art. No element, act, or
instruction used in the description of the present application
should be construed as critical or essential to the invention
unless explicitly provided as such. Functionally equivalent methods
and apparatuses within the scope of the disclosure, in addition to
those enumerated herein, will be apparent to those skilled in the
art from the foregoing descriptions. Such modifications and
variations are intended to fall within the scope of the appended
claims. The present disclosure is to be limited only by the terms
of the appended claims, along with the full scope of equivalents to
which such claims are entitled. It is to be understood that this
disclosure is not limited to particular methods or systems.
[0271] It is also to be understood that the terminology used herein
is for the purpose of describing particular embodiments only, and
is not intended to be limiting. As used herein, when referred to
herein, the terms "station" and its abbreviation "STA", "user
equipment" and its abbreviation "UE" may mean (i) a wireless
transmit and/or receive unit (WTRU), such as described infra; (ii)
any of a number of embodiments of a WTRU, such as described infra;
(iii) a wireless-capable and/or wired-capable (e.g., tetherable)
device configured with, inter alia, some or all structures and
functionality of a WTRU, such as described infra; (iii) a
wireless-capable and/or wired-capable device configured with less
than all structures and functionality of a WTRU, such as described
infra; or (iv) the like. Details of an example WTRU, which may be
representative of any UE recited herein, are provided with respect
to FIGS. 1A-1D.
[0272] In certain representative embodiments, several portions of
the subject matter described herein may be implemented via
Application Specific Integrated Circuits (ASICs), Field
Programmable Gate Arrays (FPGAs), digital signal processors (DSPs),
and/or other integrated formats. However, those skilled in the art
will recognize that some aspects of the embodiments disclosed
herein, in whole or in part, may be equivalently implemented in
integrated circuits, as one or more computer programs running on
one or more computers (e.g., as one or more programs running on one
or more computer systems), as one or more programs running on one
or more processors (e.g., as one or more programs running on one or
more microprocessors), as firmware, or as virtually any combination
thereof, and that designing the circuitry and/or writing the code
for the software and or firmware would be well within the skill of
one of skill in the art in light of this disclosure. In addition,
those skilled in the art will appreciate that the mechanisms of the
subject matter described herein may be distributed as a program
product in a variety of forms, and that an illustrative embodiment
of the subject matter described herein applies regardless of the
particular type of signal bearing medium used to actually carry out
the distribution. Examples of a signal bearing medium include, but
are not limited to, the following: a recordable type medium such as
a floppy disk, a hard disk drive, a CD, a DVD, a digital tape, a
computer memory, etc., and a transmission type medium such as a
digital and/or an analog communication medium (e.g., a fiber optic
cable, a waveguide, a wired communications link, a wireless
communication link, etc.).
[0273] The herein described subject matter sometimes illustrates
different components contained within, or connected with, different
other components. It is to be understood that such depicted
architectures are merely examples, and that in fact many other
architectures may be implemented which achieve the same
functionality. In a conceptual sense, any arrangement of components
to achieve the same functionality is effectively "associated" such
that the desired functionality may be achieved. Hence, any two
components herein combined to achieve a particular functionality
may be seen as "associated with" each other such that the desired
functionality is achieved, irrespective of architectures or
intermediate components. Likewise, any two components so associated
may also be viewed as being "operably connected", or "operably
coupled", to each other to achieve the desired functionality, and
any two components capable of being so associated may also be
viewed as being "operably couplable" to each other to achieve the
desired functionality. Specific examples of operably couplable
include but are not limited to physically mateable and/or
physically interacting components and/or wirelessly interactable
and/or wirelessly interacting components and/or logically
interacting and/or logically interactable components.
[0274] With respect to the use of substantially any plural and/or
singular terms herein, those having skill in the art can translate
from the plural to the singular and/or from the singular to the
plural as is appropriate to the context and/or application. The
various singular/plural permutations may be expressly set forth
herein for sake of clarity.
[0275] It will be understood by those within the art that, in
general, terms used herein, and especially in the appended claims
(e.g., bodies of the appended claims) are generally intended as
"open" terms (e.g., the term "including" should be interpreted as
"including but not limited to," the term "having" should be
interpreted as "having at least," the term "includes" should be
interpreted as "includes but is not limited to," etc.). It will be
further understood by those within the art that if a specific
number of an introduced claim recitation is intended, such an
intent will be explicitly recited in the claim, and in the absence
of such recitation no such intent is present. For example, where
only one item is intended, the term "single" or similar language
may be used. As an aid to understanding, the following appended
claims and/or the descriptions herein may contain usage of the
introductory phrases "at least one" and "one or more" to introduce
claim recitations. However, the use of such phrases should not be
construed to imply that the introduction of a claim recitation by
the indefinite articles "a" or "an" limits any particular claim
containing such introduced claim recitation to embodiments
containing only one such recitation, even when the same claim
includes the introductory phrases "one or more" or "at least one"
and indefinite articles such as "a" or "an" (e.g., "a" and/or "an"
should be interpreted to mean "at least one" or "one or more"). The
same holds true for the use of definite articles used to introduce
claim recitations. In addition, even if a specific number of an
introduced claim recitation is explicitly recited, those skilled in
the art will recognize that such recitation should be interpreted
to mean at least the recited number (e.g., the bare recitation of
"two recitations," without other modifiers, means at least two
recitations, or two or more recitations). Furthermore, in those
instances where a convention analogous to "at least one of A, B,
and C, etc." is used, in general such a construction is intended in
the sense one having skill in the art would understand the
convention (e.g., "a system having at least one of A, B, and C"
would include but not be limited to systems that have A alone, B
alone, C alone, A and B together, A and C together, B and C
together, and/or A, B, and C together, etc.). In those instances
where a convention analogous to "at least one of A, B, or C, etc."
is used, in general such a construction is intended in the sense
one having skill in the art would understand the convention (e.g.,
"a system having at least one of A, B, or C" would include but not
be limited to systems that have A alone, B alone, C alone, A and B
together, A and C together, B and C together, and/or A, B, and C
together, etc.). It will be further understood by those within the
art that virtually any disjunctive word and/or phrase presenting
two or more alternative terms, whether in the description, claims,
or drawings, should be understood to contemplate the possibilities
of including one of the terms, either of the terms, or both terms.
For example, the phrase "A or B" will be understood to include the
possibilities of "A" or "B" or "A and B." Further, the terms "any
of" followed by a listing of a plurality of items and/or a
plurality of categories of items, as used herein, are intended to
include "any of," "any combination of," "any multiple of," and/or
"any combination of" multiples of the items and/or the categories
of items, individually or in conjunction with other items and/or
other categories of items. Moreover, as used herein, the term "set"
or "group" is intended to include any number of items, including
zero. Additionally, as used herein, the term "number" is intended
to include any number, including zero.
[0276] In addition, where features or aspects of the disclosure are
described in terms of Markush groups, those skilled in the art will
recognize that the disclosure is also thereby described in terms of
any individual member or subgroup of members of the Markush
group.
[0277] As will be understood by one skilled in the art, for any and
all purposes, such as in terms of providing a written description,
all ranges disclosed herein also encompass any and all possible
subranges and combinations of subranges thereof .DELTA.ny listed
range can be easily recognized as sufficiently describing and
enabling the same range being broken down into at least equal
halves, thirds, quarters, fifths, tenths, etc. As a non-limiting
example, each range discussed herein may be readily broken down
into a lower third, middle third and upper third, etc. As will also
be understood by one skilled in the art all language such as "up
to," "at least," "greater than," "less than," and the like includes
the number recited and refers to ranges which can be subsequently
broken down into subranges as discussed above. Finally, as will be
understood by one skilled in the art, a range includes each
individual member. Thus, for example, a group having 1-3 cells
refers to groups having 1, 2, or 3 cells. Similarly, a group having
1-5 cells refers to groups having 1, 2, 3, 4, or 5 cells, and so
forth.
[0278] Moreover, the claims should not be read as limited to the
provided order or elements unless stated to that effect. In
addition, use of the terms "means for" in any claim is intended to
invoke 35 U.S.C. .sctn. 112, 6 or means-plus-function claim format,
and any claim without the terms "means for" is not so intended.
[0279] A processor in association with software may be used to
implement a radio frequency transceiver for use in a wireless
transmit receive unit (WTRU), user equipment (UE), terminal, base
station, Mobility Management Entity (MME) or Evolved Packet Core
(EPC), or any host computer. The WTRU may be used m conjunction
with modules, implemented in hardware and/or software including a
Software Defined Radio (SDR), and other components such as a
camera, a video camera module, a videophone, a speakerphone, a
vibration device, a speaker, a microphone, a television
transceiver, a hands free headset, a keyboard, a Bluetooth.RTM.
module, a frequency modulated (FM) radio unit, a Near Field
Communication (NFC) Module, a liquid crystal display (LCD) display
unit, an organic light-emitting diode (OLED) display unit, a
digital music player, a media player, a video game player module,
an Internet browser, and/or any Wireless Local Area Network (WLAN)
or Ultra Wide Band (UWB) module.
[0280] Although the invention has been described in terms of
communication systems, it is contemplated that the systems may be
implemented in software on microprocessors/general purpose
computers (not shown). In certain embodiments, one or more of the
functions of the various components may be implemented in software
that controls a general-purpose computer.
[0281] In addition, although the invention is illustrated and
described herein with reference to specific embodiments, the
invention is not intended to be limited to the details shown.
Rather, various modifications may be made in the details within the
scope and range of equivalents of the claims and without departing
from the invention.
[0282] Throughout the disclosure, one of skill understands that
certain representative embodiments may be used in the alternative
or in combination with other representative embodiments.
[0283] Although features and elements are described above in
particular combinations, one of ordinary skill in the art will
appreciate that each feature or element can be used alone or in any
combination with the other features and elements. In addition, the
methods described herein may be implemented in a computer program,
software, or firmware incorporated in a computer readable medium
for execution by a computer or processor. Examples of
non-transitory computer-readable storage media include, but are not
limited to, a read only memory (ROM), random access memory (RAM), a
register, cache memory, semiconductor memory devices, magnetic
media such as internal hard disks and removable disks,
magneto-optical media, and optical media such as CD-ROM disks, and
digital versatile disks (DVDs). A processor in association with
software may be used to implement a radio frequency transceiver for
use in a WRTU, UE, terminal, base station, RNC, or any host
computer.
[0284] Moreover, in the embodiments described above, processing
platforms, computing systems, controllers, and other devices
containing processors are noted. These devices may contain at least
one Central Processing Unit ("CPU") and memory. In accordance with
the practices of persons skilled in the art of computer
programming, reference to acts and symbolic representations of
operations or instructions may be performed by the various CPUs and
memories. Such acts and operations or instructions may be referred
to as being "executed," "computer executed" or "CPU executed."
[0285] One of ordinary skill in the art will appreciate that the
acts and symbolically represented operations or instructions
include the manipulation of electrical signals by the CPU. An
electrical system represents data bits that can cause a resulting
transformation or reduction of the electrical signals and the
maintenance of data bits at memory locations in a memory system to
thereby reconfigure or otherwise alter the CPU's operation, as well
as other processing of signals. The memory locations where data
bits are maintained are physical locations that have particular
electrical, magnetic, optical, or organic properties corresponding
to or representative of the data bits.
[0286] The data bits may also be maintained on a computer readable
medium including magnetic disks, optical disks, and any other
volatile (e.g., Random Access Memory ("RAM")) or non-volatile
("e.g., Read-Only Memory ("ROM")) mass storage system readable by
the CPU. The computer readable medium may include cooperating or
interconnected computer readable medium, which exist exclusively on
the processing system or are distributed among multiple
interconnected processing systems that may be local or remote to
the processing system. It is understood that the representative
embodiments are not limited to the above-mentioned memories and
that other platforms and memories may support the described
methods.
[0287] Suitable processors include, by way of example, a general
purpose processor, a special purpose processor, a conventional
processor, a digital signal processor (DSP), a plurality of
microprocessors, one or more microprocessors in association with a
DSP core, a controller, a microcontroller, Application Specific
Integrated Circuits (ASICs), Application Specific Standard Products
(ASSPs); Field Programmable Gate Arrays (FPGAs) circuits, any other
type of integrated circuit (IC), and/or a state machine.
[0288] Although the invention has been described in terms of
communication systems, it is contemplated that the systems may be
implemented in software on microprocessors/general purpose
computers (not shown). In certain embodiments, one or more of the
functions of the various components may be implemented in software
that controls a general-purpose computer.
[0289] In addition, although the invention is illustrated and
described herein with reference to specific embodiments, the
invention is not intended to be limited to the details shown.
Rather, various modifications may be made in the details within the
scope and range of equivalents of the claims and without departing
from the invention.
* * * * *