U.S. patent number 9,271,278 [Application Number 13/631,341] was granted by the patent office on 2016-02-23 for rf chain usage in a dual network architecture.
This patent grant is currently assigned to Intel Corporation. The grantee listed for this patent is Mo-Han Fong, Youn Hyoung Heo, Yujian Zhang. Invention is credited to Mo-Han Fong, Youn Hyoung Heo, Yujian Zhang.
United States Patent |
9,271,278 |
Heo , et al. |
February 23, 2016 |
RF chain usage in a dual network architecture
Abstract
An apparatus and method for using a radio frequency (RF chain)
in a dual-network architecture are disclosed herein. An evolved
node B (eNodeB) receives RF chain sharing information from user
equipment (UE) associated with the eNodeB. The RF chain sharing
information comprises indication of a non-usable frequency band or
indication of which frequency band is supported for each of a first
network and a second network that an RF chain is switchable
between. The RF chain is included in the UE and at least a
frequency band is shared between the first and second networks. The
eNodeB transmits radio resource control (RRC) connection
reconfiguration signaling to the UE to release a secondary cell
(SCell) or perform inter-frequency handover of a primary cell
(PCell) in response to the RF chain sharing information.
Inventors: |
Heo; Youn Hyoung (Seoul,
KR), Zhang; Yujian (Beijing, CN), Fong;
Mo-Han (Sunnyvale, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
Heo; Youn Hyoung
Zhang; Yujian
Fong; Mo-Han |
Seoul
Beijing
Sunnyvale |
N/A
N/A
CA |
KR
CN
US |
|
|
Assignee: |
Intel Corporation (Santa Clara,
CA)
|
Family
ID: |
48483156 |
Appl.
No.: |
13/631,341 |
Filed: |
September 28, 2012 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20130244656 A1 |
Sep 19, 2013 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61612188 |
Mar 16, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L
5/1446 (20130101); H04L 5/0055 (20130101); H04L
67/2842 (20130101); H04L 1/0033 (20130101); H04L
47/283 (20130101); H04L 1/1854 (20130101); H04W
72/0406 (20130101); H04W 72/042 (20130101); H04W
72/082 (20130101); H04W 72/1205 (20130101); H04W
24/00 (20130101); H04W 76/27 (20180201); H04L
1/08 (20130101); H04W 72/1242 (20130101); H04L
12/2854 (20130101); H04L 1/1607 (20130101); H04L
1/1887 (20130101); H04L 65/601 (20130101); H04W
52/0209 (20130101); H04L 1/0077 (20130101); H04N
21/6408 (20130101); H04L 5/1469 (20130101); H04N
21/6405 (20130101); H04W 74/085 (20130101); H04L
1/1825 (20130101); H04L 47/6275 (20130101); H04W
72/0426 (20130101); H04L 1/1812 (20130101); H04L
1/1861 (20130101); H04N 21/41407 (20130101); H04W
52/02 (20130101); H04W 72/1284 (20130101); H04W
52/0206 (20130101); H04W 72/04 (20130101); H04W
76/28 (20180201); H04L 1/1864 (20130101); H04L
67/02 (20130101); H04W 72/0413 (20130101); H04L
1/189 (20130101); H04L 1/1896 (20130101); H04L
5/1438 (20130101); H04N 21/25841 (20130101); H04W
4/06 (20130101); H04W 72/048 (20130101); H04L
1/1877 (20130101); H04L 5/001 (20130101); H04W
24/02 (20130101); H04L 5/0053 (20130101); H04W
52/0235 (20130101); H04L 5/14 (20130101); H04L
1/1635 (20130101); H04W 28/0236 (20130101); H04W
28/0278 (20130101); H04W 72/1273 (20130101); H04L
5/0073 (20130101); H04L 12/189 (20130101); H04W
16/04 (20130101); H04W 28/0268 (20130101); H04W
52/243 (20130101); H04W 52/143 (20130101); H04W
72/1268 (20130101); H04L 1/1819 (20130101); H04W
72/0446 (20130101); Y02D 30/70 (20200801); H04W
52/0229 (20130101); H04J 11/0073 (20130101) |
Current International
Class: |
H04W
72/04 (20090101); H04L 1/18 (20060101); H04L
5/14 (20060101); H04L 5/00 (20060101); H04N
21/6408 (20110101); H04W 74/08 (20090101); H04N
21/414 (20110101); H04W 72/12 (20090101); H04W
4/06 (20090101); H04W 24/02 (20090101); H04W
52/14 (20090101); H04W 52/02 (20090101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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WO-2013138065 |
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Sep 2013 |
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WO |
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Other References
"International Application Serial No. PCT/US2013/027921,
International Preliminary Report on Patentability mailed Sep. 25,
2014", 6 pgs. cited by applicant .
"International Application Serial No. PCT/US2013/027921,
International Search Report mailed May 16, 2013", 3 pgs. cited by
applicant .
"International Application Serial No. PCT/US2013/027921, Written
Opinion mailed May 16, 2013", 4 pgs. cited by applicant .
Qiang, Ni, et al., "Investigation of Bandwidth Request Mechanisms
under Point-to-MultipointMode of WiMAX Networks", IEEE
Communications Magazine See abstract; p. 232., right col., line
6--p. 135, left col., line 6., (May 2007), 7 pgs. cited by
applicant .
Sadayuki, Abeta, "Toward LTE Commercial Launch and Future Plan for
LTE Enhancements (LTE-Advanced)", IEEE See abstract; p. 146., right
col. line 11--p. 150, right col., line 12, (2010). cited by
applicant.
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Primary Examiner: Nguyen; Dinh P
Attorney, Agent or Firm: Schwegman Lundberg & Woessner,
P.A.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent
Application No. 61/612,188 entitled "Wireless Communication Systems
and Methods" filed on Mar. 16, 2012, the content of which is
incorporated herein by reference in its entirety.
Claims
What is claimed is:
1. A mobile device, comprising: a 3rd Generation Partnership
Project (3GPP) long term evolution (LTE) baseband circuitry; a 2nd
Generation (2G) or 3rd Generation (3G) baseband circuitry; and a
radio frequency (RE) chain selectively switchable between the LTE
baseband circuitry and the 2G or 3G baseband circuitry, wherein the
RE chain is arranged to transmit at least a radio frame including a
scheduling request (SR) provided in a physical uplink control
channel (PUCCH) or to initiate a Random Access procedure to an
evolved node B (eNodeB) associated with a LTE network and the RF
chain is further arranged to transmit, over a frequency band and in
response to the SR in the PUCCH or the Random Access procedure, an
Activation/Deactivation request medium access control (MAC) control
element (CE) wherein the Activation/Deactivation MAC CE comprises
an instruction to deactivate a secondary cell included in the LTE
network when the frequency band is the same as a frequency band
supported by a 2G or 3G network, wherein the secondary cell
comprises a component carrier, configured for the mobile device,
different from a primary component carrier of a primary cell
configured for the mobile device and both the primary and secondary
cells are part of the LTE network.
2. The mobile device of claim 1, wherein the
Activation/Deactivation request MAC CE is provided in response to a
voice call to be started supported by the 2G or 3G baseband
circuitry coupled to the RF chain.
3. The mobile device of claim 2, wherein the voice call comprises a
mobile originating (MO) voice call or a mobile terminating (MT)
voice call.
4. The mobile device of claim 1, wherein the RE chain is further
arranged to transmit the radio frame including the SR when a
dedicated SR resource has been allocated by the eNodeB for the
mobile device.
5. The mobile device of claim 1, wherein the mobile device
initiates the Random Access procedure when no dedicated SR resource
has been allocated by the eNodeB for the mobile device.
6. The mobile device of claim 1, wherein the mobile device receives
physical uplink shared channel (PUSCH) resource scheduled by the
eNodeB.
7. The mobile device of claim 6, wherein the mobile device sends
the Activation/Deactivation request MAC CE in the PUSCH resource
scheduled by the eNodeB.
8. The mobile device of claim 1, wherein the mobile device
transmits an Activation/Deactivation MAC CE signaling to the eNodeB
in response to the Activation/Deactivation request MAC CE provided
by the mobile device.
9. The mobile device of claim 8, wherein the
Activation/Deactivation request MAC CE comprises identification of
a cell to be activated or deactivated.
10. The mobile device of claim 1, wherein the LTE network operates
in time division duplexing (TDD) mode or frequency division
duplexing (FDD) mode.
Description
TECHNICAL HELD
The present disclosure relates generally to wireless
communications. More particularly, the present disclosure relates
to carrier aggregation support in wireless communication
systems.
BACKGROUND
Dual wireless technology architecture (also referred to as
dual-standby architecture) comprises user equipment (UE) using a
first wireless technology for voice communications (e.g., phone
calls) and a second wireless technology for data communications
(e.g., web browsing). As an example, the first wireless technology
can be 2nd Generation (2G) or 3rd Generation (3G) cellular
technology, and the second wireless technology can be a 3rd
Generation Partnership Project (3GPP) long term evolution
(LTE)-Advanced technology. In 3GPP LTE Release-10 system, carrier
aggregation (CA) is supported. CA is used to extend communication
up to 100 megahertz (MHz) in Release 10. Such large bandwidth
communication is achieved by the simultaneous aggregation of more
than one Release 8/9 component carrier having bandwidths of 1.4, 3,
5, 10, 15, and up to 20 MHz, hence the term carrier aggregation, in
which each carrier within the aggregated set of carriers is
referred to as a component carrier. Under Release 10, up to five
component carriers may be aggregated together to achieve the
maximum bandwidth of 100 MHz.
If CA is supported in dual-standby architecture, it may be possible
for a UE to share a radio frequency (RF) chain between the 2G/3G
network and LTE network if the two networks' respective frequency
bands are close to each other. If a RF chain is to be shared, the
evolved node B (eNodeB or eNB) should be notified of whether it
will be used for 2G/3G or LTE service. Currently the eNodeB is not
provided this information.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an example (portion) of a dual radio access
technology (RAT) network according to some embodiments.
FIG. 2 illustrates an example block diagram showing details of each
of eNodeBs, BSs, and UEs according to some embodiments.
FIG. 3 illustrates an example block diagram showing additional
components included in one or more of the UEs according to some
embodiments.
FIGS. 4A-4B illustrates example respective flow diagrams showing
use of radio resource control (RRC) signaling to facilitate
information sharing between a given UE and its associated eNodeB
pertaining to which network the RF chain of the given UE is/will be
supporting according to some embodiments.
FIGS. 5A-5E illustrate example timing diagrams corresponding to
FIGS. 4A-4B according to some embodiments.
FIG. 6 illustrates an example flow diagram for using
Activation/Deactivation MAC control element (CE) signaling
according to some embodiments.
FIG. 7 illustrates an example flow diagram for assignment of PCell
and SCells and/or CCs for the PCell and SCells for the UE 122 that
can be controlled by the network to avoid frequency co-existence
issues from occurring beforehand.
DETAILED DESCRIPTION
The following description is presented to enable any person skilled
in the art to create and use a computer system configuration and
related method and article of manufacture to notify an eNodeB of
which network a RF chain switchable between at least two disparate
networks (e.g., LTE and 3G, LTE and 2G, etc.) will be supporting in
connection with a service event (e.g., start of a voice call) are
described herein. The switchable RF chain is included in a UE
capable of dual-network operation. The dual network architecture
supports CA. The UE provides notification to its associated eNodeB
when the frequency band to be used for the service event (e.g.,
2G/3G voice call) is the same as or close to the frequency band
used for the other network service (e.g., LTE service). In some
embodiments RRC signaling is used to provide the information about
RF sharing to the eNodeB. In other embodiments
Activation/Deactivation MAC CE signaling is triggered by RF sharing
information provided by the HE to the eNodeB. In still other
embodiments PCell and SCells and/or CCs for the PCell and SCells
are judiciously assigned to the so as to minimize frequency
co-existence issues.
Various modifications to the embodiments will be readily apparent
to those skilled in the art, and the generic principles defined
herein may be applied to other embodiments and applications without
departing from the scope of the invention. Moreover, in the
following description, numerous details are set forth for the
purpose of explanation. However, one of ordinary skill in the art
will realize that embodiments of the invention may be practiced
without the use of these specific details. In other instances,
well-known structures and processes are not shown in block diagram
form in order not to obscure the description of the embodiments of
the invention with unnecessary detail. Thus, the present disclosure
is not intended to be limited to the embodiments shown, but is to
be accorded the widest scope consistent with the principles and
features disclosed herein.
FIG. 1 illustrates an example (portion) of a dual radio access
technology (RAT) network 100 according to some embodiments. Network
100 represents an example dual-standby or dual-network
architecture. In one embodiment, the network 100 comprises a 3rd
Generation Partnership Project (3GPP) long term evolution
(LTE)-Advanced technology network 101 and a 2nd Generation (2G) or
3rd Generation (3G) RAT network 103. The 2G RAT network 103
comprises a network based on the Global System for Mobile (GSM) or
Code Division Multiple Access (CDMA) standard. The 3G RAT network
103 comprises a network based on the Universal Mobile
Telecommunications System (UMTS) or Evolved High Speed Packet
Access (HSPA+) standard. The LTE RAT network 101 operates in either
time division duplexing (TDD) mode or frequency division duplexing
(FDD) mode. The LTE network 101 includes an evolved node B (eNodeB
or eNB) 102, an eNodeB 106, and a core network 118. The 2G/3G
network 103 includes a base station (BS) 110, a BS 114, and a core
network 120.
The eNodeB 102 (also referred to as a base station) serves a
certain geographic area that includes at least a cell 104. A
plurality of user equipment (UEs) 122 associated with the cell 104
communicates with the eNodeB 102 on one or more specific
frequencies, the eNodeB 102 providing control and radio air
interface functionalities for cell 104. The eNodeB 106 (also
referred to as a base station) is similar to eNodeB 102 except it
serves a different cell from that of eNodeB 102. The eNodeB 106
serves a certain geographic area that includes at least a cell 108.
A plurality of UEs 122 associated with the cell 108 communicates
with the eNodeB 106 on one or more specific frequencies, the eNodeB
106 providing control and radio air interface functionalities for
cell 108.
Each of the eNodeBs 102, 106 communicates with the core network
118. Core network 118 includes, but is not limited to, a mobility
management entity (MME), a home location registrar (HLR)/home
subscriber server (HSS), serving gateway (SGW), and other LTE
network components providing network functionalities not provided
by an eNodeB.
The BS 110 serves a certain geographic area that includes at least
a cell 112. A plurality of UEs 122 associated with the cell 112
communicates with the BS 110 on one or more specific frequencies,
the BS 110 providing control and radio air interface
functionalities for cell 112. The BS 114 is similar to BS 110
except it serves a different cell from that of BS 110. The BS 114
serves a certain geographic area that includes at least a cell 116.
A plurality of UEs 122 associated with the cell 116 communicates
with the BS 114 on one or more specific frequencies, the BS 114
providing control and radio air interface functionalities for cell
116.
Each of the BSs 110, 114 communicates with the core network 120.
Core network 120 includes, but is not limited to, base station
controllers (BSCs), a mobile switching center (MSC), and other
2G/3G network components providing network functionalities not
provided by a BS.
The cells 104, 108, 112, 116 may or may not be immediately
co-located next to each other. As another example, the respective
coverage areas of the cells 104, 108, 112, 116 may overlap with
each other. As still another example, the respective coverage areas
of the cells 104, 108, 112, 116 may be distinct or isolated from
each other. It is understood that the network 100 includes more
than two eNodeBs and more than two BSs, each of such eNodeBs or BSs
serving a cell.
The UEs 122 (also referred to as mobile devices) comprises a
variety of devices that communicate within the network 100
including, but not limited to, cellular telephones, smart phones,
tablets, laptops, desktops, personal computers, servers, personal
digital assistants (PDAs), web appliances, set-top box (STB), a
network router, switch or bridge, and the like. The UEs 122
comprise dual RAT UEs capable of switching operation between the
LTE network and 2G/3G network. In one embodiment, each of the UEs
122 may access the 2G/3G network via BS 110 or 114 for voice (phone
calls) and access the LTE network via eNodeB 102 or 106 for data
(web browsing, emails).
When operating in LTE mode, the UEs 122 located in respective cells
104, 108 transmits data to its respective eNodeB 102, 106 (uplink
transmission) and receives data from its respective eNodeB 102, 106
(downlink transmission) using radio frames comprising Orthogonal
Frequency-Division Multiple Access (OFDMA) frames. For Release-10
or later LTE networks 101, carrier aggregation (CA) is supported,
in which up to five frequency bands corresponding to five component
carriers (CCs) can be aggregated to expand the overall bandwidth of
the network (e.g., up to a bandwidth of 100 MHz). For each of the
UEs 122 at a given point in time, a CC is defined as a given UE
122's primary cell (PCell). If more than one CC is configured for
the given UE 122, the additional CCs are referred to as secondary
cells (SCells). For instance, cell 104 can be designated as the
PCell for a given UE 122 while cell 108 is designated as the SCell
for the same given UE 122. In Release-10 or later LTE CA, a
plurality of serving cells are served by the same eNodeB. For
example, eNodeB 102 may serve cell 104 and one or more other cells
not shown in FIG. 1.
FIG. 2 illustrates an example block diagram showing details of each
of eNodeBs 102, 106, BSs 110, 114, and UEs 122 according to some
embodiments. Each of the eNodeBs 102, 106, BSs 110, 114, and UEs
122 includes a processor 200, a memory 202, a transceiver 204,
instructions 206, and other components (not shown). The eNodeBs
102, 106, BSs 110, 114, and UEs 122 can be similar to each other in
hardware, firmware, software, configurations, and/or operating
parameters.
The processor 200 comprises one or more central processing units
(CPUs), graphics processing units (GPUs), or both. The processor
200 provides processing and control functionalities for the eNodeBs
102, 106, BSs 110, 114, and UEs 122. Memory 202 comprises one or
more transient and static memory units configured to store
instructions and data for the eNodeBs 102, 106, BSs 110, 114, and
UEs 122. The transceiver 204 comprises one or more transceivers
including a multiple-input and multiple-output (MIMO) antenna to
support MIMO communications. The transceiver 204 receives uplink
transmissions and transmits downlink transmissions, among other
things, from and to the UEs respectively.
The instructions 206 comprises one or more sets of instructions or
software executed on a computing device (or machine) to cause such
computing device (or machine) to perform any of the methodologies
discussed herein. The instructions 206 (also referred to as
computer- or machine-executable instructions) may reside,
completely or at least partially, within the processor 200 and/or
the memory 202 during execution thereof by the eNodeBs 102, 106,
BSs 110, 114, and UEs 122. The processor 200 and memory 202 also
comprise machine-readable media.
FIG. 3 illustrates an example block diagram showing additional
components included in one or more of the UEs 122 according to some
embodiments. In one embodiment, a given UE 122 includes at least
one RF chain 302. When CA is supported (e.g., in Release 10 or
later LTE network 101) in the network 100, the given UE 122 is
implemented with multiple RF chains. The given UE 122 can be
configured to share the RF chain 302 between LTE service and 2G/3G
service if the respective frequency bands are close to each other.
As shown in FIG. 3, the RF chain 302 is selectively connectable or
switchable to a LTE baseband (BB) 304 or a 2G/3G BB 306. Each of
the LTE BB 304 and 2G/3G BB 306 comprises a BB integrated circuit
(IC) chip. Each of the LTE BB 304 and 2G/3G BB 306 can be provided
on separate IC chips, or together on a single IC chip. The RF chain
302 includes, but is not limited to, a digital-to-analog
(D/A)/analog-to-digital (D/A) converter, decoder/encoder,
modulator/demodulator, filter, power amplifier (PA), and local
oscillator (LO).
When the RF chain 302 is switched to the LTE BB 304, the given UE
122 operates in the LTE network and an antenna 308 transmits or
receives wireless signals configured according to the LTE standard.
When the RF chain 302 is switched to the 2G/3G BB 306, the given UE
122 operates in the 2G/3G network and the antenna transmits or
receives wireless signals configured according to the 2G/3G
standard. If the RE chain 302 is being used to support a LTE
service, for example, then the RF chain 302 cannot simultaneously
be used to support a 2G/3G service. Thus, the eNodeB associated
with the given UE 122 is informed of which network the RF chain 302
is supporting.
FIGS. 4A-4B illustrates example flow diagrams 400 and 420,
respectively, showing use of radio resource control (RRC) signaling
to facilitate information sharing between a given UE 122 and an
eNodeB (e.g., eNodeB 102 or 106) pertaining to which network the RF
chain 302 of the given UE 122 is/will be supporting according to
some embodiments. FIGS. 5A-5B illustrate example timing diagrams
corresponding to FIG. 4A according to some embodiments. FIGS. 5C-5E
illustrate example timing diagrams corresponding to FIG. 4B
according to some embodiments.
FIGS. 4A and 5A correspond to the given UE 122 originating a voice
call (also referred to as a mobile originating (MO) call) and
correspondingly, configuring its RF chain 302 to connect to the
2G/3G BB 306 to operate on the 2G/3G network. At a block 402a of
FIG. 4A, a given eNodeB (e.g., eNodeB 102 or 106) associated with
the given UE 122 receives UE capability signaling from the given UE
122 (communication 502 in FIG. 5A). The UE capability signaling
comprises RF sharing information (also referred to as RF chain
sharing information) informing the given eNodeB whether RF chain
302 is shared between LTE and 2G/3G for each supported frequency
band or frequency band combination (each frequency band of each
supported frequency bandwidth provided by CA). After the UE
capability signaling is received by the given eNodeB, the given UE
122 goes into connected mode (connected mode 503 in FIG. 5A) if
there is a packet switched call in LTE. Connected mode occurs upon
the given UE 122 completing the initial RRC connection setup
procedure with the given eNodeB.
Next at a block 404a, the given eNodeB transmits to the given UE
122, RRC connection reconfiguration signaling comprising CA
configuration if there is no voice call on-going in 2G/3G
(communication 504 in FIG. 5A). When the given UE 122 starts a MO
call 505 after block 404a, the given UE 122 transmits a circuit
switched (CS) service indicator to the given eNodeB (communication
506 in FIG. 5A). The CS service indicator is received by the given
eNodeB, at a block 406a, the CS service indicator informing the
given eNodeB of the start of a MO call by the given UE 122.
At a block 408a, in response to receiving the CS service indicator,
the given eNodeB determines whether to send a message for the given
UE 122 to release a SCell or to handover to a new PCell. In CA,
there are a number of serving cells, one cell for each CC included
in the CA. The cell corresponding to a given CC operates at a
specific frequency band from the other CCs within the CA. The
coverage area of a cell for a CC can be different from a cell for
another CC. The cells for one or more CCs can be served by the same
eNodeB. When more than one CC is associated with the given UE 122
(in other words, more than one cell is associated with the given UE
122), the cell corresponding to one of these CCs is designated as
the PCell for the given UE 122. The remaining cells corresponding
to the remaining associated CCs are referred to as SCells for the
given UE 122. Only the PCell is responsible for mobility management
such as providing non-access-stratum (NAS) mobility information or
security keys. SCells can be added or removed, as required, for the
given UE 122 with RRC connection reconfiguration, while the PCell
association changes by performing handover to a new/different
PCell.
The given eNodeB transmits a RRC connection reconfiguration
message/signaling to the given UE 122 to release a particular SCell
associated with the given UE 122, if the particular SCell
corresponds to the frequency band that is shared with 2G/3G service
(communication 508 in FIG. 5A). The eNodeB commands the given UE
122 to release the particular SCell so that there is no inadvertent
use of the frequency band, which will be used for the MO call via
2G/3G service, for some other purpose. Releasing a cell refers to
temporarily placing a hold on maintaining a connection with and/or
use of the cell. If there is no common frequency band between the
SCells and 2G/3G service and the current/source PCell corresponds
to the frequency band shared for 2G/3G service, then the given
eNodeB transmits a RRC connection reconfiguration message/signaling
to the given UE 122 to perform inter-frequency handover (HO) of the
PCell to another carrier frequency (communication 508 in FIG. 5A).
In general the RRC connection reconfiguration message with mobility
control information is providing instructions to release the
source/current PCell and handover to another cell in the different
carrier frequency.
Once the given UE 122 has taken action in accordance with the RRC
connection reconfiguration message in block 408a, the given UE 122
turns on 2G/3G service 509 (FIG. 5A) and camps on a 2G/3G cell for
the duration of the MO call. While camping on a 2G/3G cell, the
given UE 122 maintains connection with LTE cells (the associated
PCell and SCell(s) except for the cell instructed to be released in
block 408a).
FIGS. 4A and 5B correspond to the given UE 122 receiving a voice
call (also referred to as a mobile terminating (MT) call) and
correspondingly, configuring its RF chain 302 to connect to the
2G/3G BB 306 to operate on the 2G/3G network. FIG. 5B is similar to
FIG. 5A with the exception of communication 516 (instead of
communication 506) and involvement of the 2G/3G network 103.
At a block 402b of FIG. 4A, a given eNodeB (e.g., eNodeB 102 or
106) associated with the given UE 122 receives UE capability
signaling from the given UE 122 (communication 512 in FIG. 5B). The
UE capability signaling comprises RF sharing information informing
the given eNodeB whether RF chain 302 is shared between LTE and
2G/3G for each supported frequency band or frequency band
combination (each frequency band of each supported frequency
bandwidth provided by CA). After the UE capability signaling is
received by the given eNodeB, the given UE 122 goes into connected
mode (connected mode 513 in FIG. 5B) if there is a packet switched
call in LTE. Connected mode occurs upon the given UE 122 completing
the initial RRC connection setup procedure with the given
eNodeB.
Next at a block 404b, the given eNodeB transmits to the given UE
122, RRC connection reconfiguration signaling comprising CA
configuration if there is no voice call on-going in 2G/3G
(communication 514 in FIG. 5B), When a MT call starts 515 after
block 404b, the 2G/3G core network 120, e.g., the mobile switching
centre server (MSC) included in the 2G/3G core network 120, sends a
paging request to the LTE core network 120, e.g., the MME included
in the LTE core network 120 (communication 516 in FIG. 5B). The
paging request includes information such as, but not limited to, UE
identity and Paging cause. The MME, in turn, informs the given
eNodeB that there is a MT call started using 2G/3G for the given UE
122. Thus, the given eNodeB (indirectly) receives the paging
request from the 2G/3G network 103 in response to start of a MT
call 515 on the 2G/3G network 103 (block 406b).
At a block 408b, in response to receiving the paging request, the
given eNodeB determines whether to send a message for the given UE
122 to release a SCell or to handover to a new PCell. The given
eNodeB transmits a RRC connection reconfiguration message/signaling
to the given UE 122 to release a particular SCell associated with
the given UE 122, if the particular SCell corresponds to the
frequency band that is shared with 2G/3G service (communication 518
in FIG. 5B). The eNodeB commands the given UE 122 to release the
particular SCell so that there is no inadvertent use of the
frequency band, which will be used for the MT call using 2G/3G
service, for some other purpose. If there is no common frequency
band between the SCells and 2G/3G service and the current/source
PCell corresponds to the frequency band shared for 2G/3G service,
then the given eNodeB transmits a RRC connection reconfiguration
message/signaling to the given UE 122 to perform inter-frequency
handover (HO) of the PCell to another carrier frequency
(communication 518 in FIG. 5B). In general the RRC connection
reconfiguration message with mobility control information is
providing instructions to release the source/current PCell and
handover to another cell in the different carrier frequency.
Once the given UE 122 has taken action in accordance with the RRC
connection reconfiguration message in block 408b, the given UE 122
turns on 2G/3G service 519 (FIG. 5B) and camps on a 2G/3G cell to
receive paging information corresponding to the MT call. While
camping on a 2G/3G cell, the given UE 122 maintains connection with
LTE cells (the associated PCell and SCell(s) except for the cell
instructed to be released in block 408b).
In some embodiments, at the block 408b, in order to reduce delay in
starting the voice call using the 2G/3G network 103 due to page
reception, the given eNodeB can send the 2G/3G paging to the given
UE 122 (rather than a given BS of the 2G/3G network 103, such as BS
110 or 114, sending the 2G/3G paging to the given UE 122). Such
2G/3G paging information (also referred to as 2G/3G voice call
indication) can be included in the RRC connection reconfiguration
message pertaining to SCell release or PCell HO (communication
518). Then the 2G/3G network 103 can start random access for the MT
call without receiving a return page in the 2G/3G cell.
FIG. 4B illustrates an example flow diagram 420 showing an
alternative use of RRC signaling to facilitate information sharing
between a given UE 122 and an eNodeB (e.g., eNodeB 102 or 106)
pertaining to which network the RF chain 302 of the given UE 122
is/will be supporting according to some embodiments. FIGS. 5C-5E
illustrate example timing diagrams corresponding to FIG. 4B
according to some embodiments.
FIGS. 4B and 5C correspond to the given UE 122 originating a voice
call (MO call) and the RF chain 302 included in the UE 122
connecting to the 2G/3G BB 306 to operate on the 2G/3G network.
Although not shown, initial RRC connection setup signaling occurred
between the given UE 122 and its associated eNodeB (e.g., eNodeB
102 or 106) in order for the given UE 122 to be in connected mode
521 (see FIG. 5C).
Next at a block 422a of FIG. 4B, the given eNodeB transmits a RRC
connection reconfiguration signaling comprising CA configuration to
the given UE 122 (communication 522 at FIG. 5C). This RRC
connection reconfiguration signaling is provided if there is no
voice call on-going in 2G/3G. Once the given UE 122 initiates a MO
call 523, the UE 122 sends a non-usable frequency indication to the
given eNodeB (communication 524 in FIG. 5C). The non-usable
frequency indication is received by the given eNodeB (block 424a).
The non-usable frequency indication comprises identification of one
or more frequency bands or frequency band combinations (each
frequency band of each supported frequency bandwidth provided by
CA) that cannot be used for LTE temporarily even those it is a
supported frequency band or frequency band combination. Each of the
supported frequency band or frequency band combination is the same
as those concerning the UE capability signaling discussed above
with respect to FIGS. 4A, 5A, and 5B. The identified one or more
frequency bands or frequency band combinations cannot be
simultaneously used with the current LTE serving cells due to RE
sharing (e.g., will be used for the 2G/3G voice call) or other
limitation of the dual-standby architecture.
In response to receiving the non-usable frequency indication, the
given eNodeB determines and transmits RRC connection
reconfiguration signaling instructing the UE 122 to release a
particular SCell or to perform inter-frequency HO of PCell to
another carrier frequency (block 426a) (communication 526).
Additional details regarding SCell release or PCell HO is discussed
above with respect to blocks 408a and b. Once the given UE 122 has
taken action in accordance with the RRC connection reconfiguration
message in block 426a, the given UE 122 turns on 2G/3G 527 and
camps on a 2G/3G cell for the duration of the MO call. While
camping on a 2G/3G cell, the given UE 122 maintains connection with
LTE cells (the associated PCell and SCell(s) except for the cell
instructed to be released in block 426a).
In contrast to the UE capability signaling scheme discussed above
with respect to FIG. 4A, the eNodeB does not necessarily know that
the given UE 122 shares the RF chain 302 between LTE and 2G/3G when
non-usable frequency indication is used instead. The eNodeB is
merely notified when a certain frequency band or frequency band
combination among the supported frequency band(s)/frequency band
combination(s) is being reserved and therefore not available for
use by the LTE serving cells.
FIGS. 4B, 5D, and 5E correspond to the given UE 122 receiving a
voice call (MT call) and attempting to connect the RF chain 302
included in the UE 122 to the 2G/3G BB 306 to operate on the 2G/3G
network 103. Although not shown, initial RRC connection setup
signaling occurred between the given UE 122 and its associated
eNodeB (e.g., eNodeB 102 or 106) in order for the given UE 122 to
be in connected mode 531 (see FIG. 5D).
Next at a block 422b of FIG. 4B, the given eNodeB transmits a RRC
connection reconfiguration signaling comprising CA configuration to
the given UE 122 (communication 532 at FIG. 5D). This RRC
connection reconfiguration signaling is provided if there is no
voice call on-going in 2G/3G. When the UE 122 anticipates receiving
a 2G/3G paging, UE 122 sends a non-usable frequency indication to
the given eNodeB (communication 534 in FIG. 5D). The non-usable
frequency indication is received by the given eNodeB (block 424b).
The non-usable frequency indication comprises identification of one
or more frequency bands or frequency band combinations (each
frequency band of each supported frequency bandwidth provided by
CA) that cannot be used for LTE temporarily even those it is a
supported frequency band or frequency band combination. Each of the
supported frequency band or frequency band combination is the same
as those concerning the UE capability signaling discussed above
with respect to FIGS. 4A, 5A, and 5B. The identified one or more
frequency bands or frequency band combinations cannot be
simultaneously used with the current LTE serving cells due to RF
sharing (e.g., will be used for a 2G/3G voice call) or other
limitation of the dual-standby architecture.
The UE 122 may know that the 2G/3G paging occasion as already
defined by the 2G/3G network 103 or a new 2G/3G paging occasion
will be defined for this operation in the LTE network 101. If the
paging occasion is already defined, the UE 122 also provides paging
related parameters and information about the difference of system
frame number between LTE and 2G/3G to the given eNodeB. In some
embodiments, the non-usable frequency indication or additional
signaling sent by the UE 122 with the non-usable frequency
indication provides additional information such as, but not limited
to, the following. Such information is correspondingly received by
the eNodeB at the block 426a. The purpose of the non-usable
frequency indication such as whether it is for paging, voice call,
or measurement. If the non-usable frequency indication pertains to
paging or measurement, also specifying the periodicity and duration
of the non-usable frequency band/frequency band combination. With
this information, the eNodeB can configure a measurement gap
pattern to enable the UE 122 to receive a 2G/3G paging. The
measurement gap pattern may comprise an existing measurement gap
pattern or a new measurement gap pattern that is introduced to
align with the 2G/3G paging cycle and duration. The measurement gap
pattern may apply to a subset of the serving cells to be turned off
to receive 2G/3G paging. Depending on the configuration of the
measurement gap pattern, the UE 122 may not need to transmit a
non-usable frequency indication each paging cycle to receive a
2G/3G paging. Measurement information is needed when the
measurement gap pattern is not configured.
In response to receiving the non-usable frequency indication (and
other possible information discussed immediately above), the given
eNodeB determines and transmits RRC connection reconfiguration
signaling instructing the UE 122 to release a particular SCell or
to perform inter-frequency HO of PCell to another carrier frequency
(block 426b) (communication 536). Additional details regarding
SCell release or PCell HO is discussed above with respect to blocks
408a and b.
If 2G/3G operation is possible based on the RRC connection
reconfiguration signaling, the UE 122 turns on 2G/3G 537 (e.g.,
camps on a 2G/3G cell) and attempts to receive 2G/3G paging. When a
MT voice call starts 538, the 2G/3G network 103 (e.g., a BS, such
as BS 110 or 114) sends a 2G/3G paging to the given UE 122
(communication 540 in FIG. 5D). In response, the UE 122 initiates
voice service via 2G/3G while maintaining connection with the given
eNodeB for packet switch (PS) service.
FIG. 5E illustrates the case where the 2G/3G paging (communication
540 in FIG. 5D) is either not sent or otherwise not properly
received by the given UE 122. In this case the UE 122 turns off
2G/3G 541 and turns back on LTE 542--in other words, switching the
RF chain 302 from the 2G/3G BB 306 to LTE BB 304 (FIG. 3). Then the
UE 122 sends a usable frequency indication to the given eNodeB
(communication 544). The usable frequency indication is received by
the eNodeB at a block 428b. The usable frequency indication
comprises informing the eNodeB of the change to the previously sent
non-usable frequency indication (that it is now usable again) or
providing new usable frequency information, for such frequency band
or frequency band combination to be available for use by the LTE
serving cells. In response, at a block 430b and at communication
546, the eNodeB determines and transmits RRC connection
reconfiguration signaling to the UE 122 comprising instructions to
release a particular SCell or to perform inter-frequency HO of
PCell to another carrier frequency. Additional details regarding
SCell release or PCell HO is discussed above with respect to blocks
408a and b.
Alternatively, the eNodeB can inform the UE 122 that there is a
2G/3G paging pending. In response, the UE 122 returns a non-usable
frequency indication to the eNodeB to temporarily reserve frequency
band/frequency band combination for use on the 2G/3G network 103
for the 2G/3G voice call. In this case the UE 122 may not require
2G/3G paging from the 2G/3G network 103 (such as communication 540)
in order to conduct the 2G/3G voice call.
In contrast to the RRC signaling approach discussed above, an
alternative embodiment for informing the eNodeB whether the RF
chain 302 of a given UE 122 is/will be used for 2G/3G service
rather than LTE service is via enhancement of medium access control
(MAC) signaling.
FIG. 6 illustrates an example flow diagram 600 for using
Activation/Deactivation MAC control element (CE) signaling
according to some embodiments. If a 2G/3G voice call (MO or MT
call) is about to start on the given UE 122 (yes branch of block
602), then the existence of dedicated scheduling request (SR)
resource for the given UE 122 is checked at a block 604. The UE 122
may or may not have uplink (UL) resources allocated for new
transmission by the given eNodeB at the point of time of the start
of the 2G/3G voice call. However, regardless of whether allocated
UL resources exist, the eNodeB should be informed of the start of
the 2G/3G voice call so that the frequency band/combination that
will be used for that call is not used by the LTE serving cells
associated with the UE 122 for the duration of the call.
If dedicated SR resource(s) are configured and exists (yes branch
of block 604), then the UE 122 transmits SR information on the
physical uplink control channel (PUCCH) included in at least one
subframe of a radio frame to the eNodeB (block 606). If dedicated
SR resource(s) are not allocated for the UE 122 (no branch of block
604), then the UE 122 initiates and participates in Random Access
procedure to provide the requisite 2G/3G voice call information to
the eNodeB (block 608).
In response to either the SR information or Random Access
procedure, the eNodeB schedules uplink physical uplink shared
channel (PUSCH) resource. The UE 122 transmits
Activation/Deactivation request MAC CE signaling (block 610). In
response to such request signaling, the eNodeB sends an
Activation/Deactivation MAC CE signaling instructing the UE 122 to
deactivate a particular SCell or PCell operating in the LTE
frequency band that cannot co-exist with the 2G/3G frequency band
to be used for the 2G/3G voice call. The Activation/Deactivation
MAC CE signaling is received by the UE 122, at a block 612. Thus,
the Activation/Deactivation request MAC CE signaling is sent by the
UE 122 sooner than it otherwise would be--triggered by the SR
information on the PUCCH or Random Access procedure--in order to
prevent delay in start of the voice call on the 2G/3G network. The
UE 122 can request the deactivation of the PCell in the
Activation/Deactivation request MAC CE signaling.
As another alternative embodiment, assignment of PCell and SCells
and/or CCs for the PCell and SCells for the given UE 122 can be
controlled by the network 100 to avoid frequency co-existence
issues from occurring beforehand. As shown in an example flow
diagram 700 of FIG. 7, for example, when CA is configured, the cell
that is used for RRC connection setup is a PCell. It is likely that
the cell that the UE 122 is camped on for LTE service is the PCell
unless HO is triggered to change the PCell, and that the LTE
frequency band that cannot co-exist during the 2G/3G voice service
is that associated with the PCell. Therefore, the UE 122 can
proactively consider or determine a 2G/3G cell having a frequency
band that cannot co-exist with LTE PCell as a barred cell or the
lowest priority cell (block 702a). With this approach, the UE 122
can avoid camping on such 2G/3G cell which cannot co-exist with the
LTE PCell (block 704a).
As another example, because a PCell cannot be deactivated for a
given UE 122, if the RF chain 302 is capable of supporting all LTE
frequency bands (block 702b), the network 100 assigns a cell having
the same frequency band/combination as would be used for 2G/3G
service by the RF chain 302 as a SCell (rather than a PCell) (block
704b). Thus, that SCell may be deactivated when the RF chain 302 is
switched to support 2G/3G service.
The term "machine-readable medium," "computer readable medium," and
the like should be taken to include a single medium or multiple
media (e.g., a centralized or distributed database, and/or
associated caches and servers) that store the one or more sets of
instructions. The term "machine-readable medium" shall also be
taken to include any medium that is capable of storing, encoding or
carrying a set of instructions for execution by the machine and
that cause the machine to perform any one or more of the
methodologies of the present disclosure. The term "machine-readable
medium" shall accordingly be taken to include, but not be limited
to, solid-state memories, optical and magnetic media, and carrier
wave signals.
It will be appreciated that, for clarity purposes, the above
description describes some embodiments with reference to different
functional units or processors. However, it will be apparent that
any suitable distribution of functionality between different
functional units, processors or domains may be used without
detracting from embodiments of the invention. For example,
functionality illustrated to be performed by separate processors or
controllers may be performed by the same processor or controller.
Hence, references to specific functional units are only to be seen
as references to suitable means for providing the described
functionality, rather than indicative of a strict logical or
physical structure or organization.
Although the present invention has been described in connection
with some embodiments, it is not intended to be limited to the
specific form set forth herein. One skilled in the art would
recognize that various features of the described embodiments may be
combined in accordance with the invention. Moreover, it will be
appreciated that various modifications and alterations may be made
by those skilled in the art without departing from the scope of the
invention.
The Abstract of the Disclosure is provided to quickly ascertain the
nature of the technical disclosure. It is submitted with the
understanding that it will not be used to interpret or limit the
scope or meaning of the claims. In addition, in the foregoing
Detailed Description, it can be seen that various features are
grouped together in a single embodiment for the purpose of
streamlining the disclosure. This method of disclosure is not to be
interpreted as reflecting an intention that the claimed embodiments
require more features than are expressly recited in each claim.
Rather, as the following claims reflect, inventive subject matter
lies in less than all features of a single disclosed embodiment.
Thus the following claims are hereby incorporated into the Detailed
Description, with each claim standing on its own as a separate
embodiment.
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