U.S. patent application number 17/011154 was filed with the patent office on 2020-12-24 for split precoding and split prefiltering between a central unit and a distributed unit of a generation node-b (gnb).
The applicant listed for this patent is Apple Inc.. Invention is credited to Wenting Chang, Qian Li, Xiaowen Zhang, Yushu Zhang, Feng Zhou.
Application Number | 20200403655 17/011154 |
Document ID | / |
Family ID | 1000005064953 |
Filed Date | 2020-12-24 |
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United States Patent
Application |
20200403655 |
Kind Code |
A1 |
Zhou; Feng ; et al. |
December 24, 2020 |
Split Precoding and Split Prefiltering Between a Central Unit and a
Distributed Unit of a Generation Node-B (GNB)
Abstract
Embodiments of a Generation Node-B (gNB) and methods of
communication are disclosed herein. The gNB may be configured with
logical nodes including a gNB central unit (gNB-CU) and a gNB
distributed unit (gNB-DU). The gNB-CU 106 may determine a first
precoding matrix and a second precoding matrix for a precoding of
one or more data streams for transmission on a plurality of
antennas coupled to the gNB-DU. The precoding may be in accordance
with a split functionality between the gNB-CU and the gNB-DU that
includes: precoding by the gNB-CU with the first precoding matrix,
and precoding by the gNB-DU with the second precoding matrix.
Inventors: |
Zhou; Feng; (Beijing,
CN) ; Zhang; Yushu; (Beijing, CN) ; Zhang;
Xiaowen; (Shanghai, CN) ; Chang; Wenting;
(Beijing, CN) ; Li; Qian; (Beaverton, OR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Apple Inc. |
Cupertino |
CA |
US |
|
|
Family ID: |
1000005064953 |
Appl. No.: |
17/011154 |
Filed: |
September 3, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16100773 |
Aug 10, 2018 |
10771131 |
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17011154 |
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62543864 |
Aug 10, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04B 7/026 20130101;
H04W 72/14 20130101; H04B 7/0615 20130101; H04W 72/085 20130101;
H04B 7/0626 20130101; H04B 7/046 20130101; H04B 7/0417 20130101;
H04L 5/0051 20130101; H04B 7/0456 20130101; H04B 7/022
20130101 |
International
Class: |
H04B 7/0456 20060101
H04B007/0456; H04B 7/026 20060101 H04B007/026; H04L 5/00 20060101
H04L005/00; H04W 72/08 20060101 H04W072/08; H04B 7/0417 20060101
H04B007/0417; H04B 7/022 20060101 H04B007/022 |
Claims
1-23. (canceled)
24. A base station comprising: a central unit (CU) and a
distributed unit (DU) coupled by an interface; wherein the DU is
coupled to a plurality of antennas, wherein the CU is configured to
receive signal quality information from the DU via the interface,
wherein the signal quality information is related to one or more
signal quality measurements.
25. The base station of claim 24, wherein the antennas are
configured to receive an uplink signal from a user equipment (UE)
device, wherein the DU is configured to decode the one or more
signal quality measurements from the uplink signal.
26. The base station of claim 24, wherein the DU is configured to
receive a sounding reference signal (SRS) from an uplink signal,
and provide the SRS to the CU through the interface.
27. The base station of claim 24, wherein the DU is configured to
receive a random access channel (RACH) from an uplink signal, and
provide the RACH to the CU through the interface.
28. The base station of claim 24, wherein physical layer processing
of the base station is split between the CU and DU.
29. The base station of claim 24, wherein the DU is configured to
pre-filter antenna-specific components of an uplink signal, and
transfer symbols of the pre-filtered signal to the CU via the
interface.
30. The base station of claim 24, wherein a first of the one or
more signal quality measurements is received signal power or
average received signal power.
31. The base station of claim 24, wherein a first of the one or
more signal quality measurements is signal-to-noise ratio (SNR) or
reference signal received power (RSRP).
32. The base station of claim 24, wherein a first of the one or
more signal quality measurements is reference signal received
quality (RSRQ) or received signal strength indicator (RSSI).
33. The base station of claim 24, wherein the CU and DU are not
co-located.
34. The base station of claim 24, wherein the CU is configured to
determine a first precoding matrix and a second precoding matrix
for precoding a transmission of one or more downlink data streams
via the plurality of antennas, wherein the CU is configured to
apply a first portion of the precoding using the first precoding
matrix, wherein the DU is configured to apply a second portion of
the precoding using the second precoding matrix.
35. A method for operating a base station, the method comprising:
sending signal quality information from a distributed unit (DU) of
the base station to a central unit (CU) of the base station,
wherein the DU is coupled to a plurality of antennas, wherein the
signal quality information is related to one or more signal quality
measurements.
36. The method of claim 35, further comprising: receiving, at the
DU, an uplink signal from a user equipment (UE) device; and
decoding, at the DU, the one or more signal quality measurements
from the uplink signal.
37. The method of claim 35, wherein a first of the one or more
signal quality measurements is one of the following: received
signal power, average received signal power, signal-to-noise ratio
(SNR), reference signal received power (RSRP), reference signal
received quality (RSRQ), received signal strength indicator
(RSSI).
38. The method of claim 35, further comprising: receiving, at the
DU, a sounding reference signal (SRS) from an uplink signal; and
providing the SRS to the CU.
39. The method of claim 35, further comprising: receiving a random
access channel (RACH) from an uplink signal, and providing the RACH
to the CU.
40. The method of claim 35, wherein physical layer processing of
the base station is split between the CU and DU.
41. The method of claim 35, further comprising: pre-filtering, at
the DU, antenna-specific components of an uplink signal; and
transferring symbols of the pre-filtered signal to the CU.
42. The method of claim 36, wherein the CU and DU are not
co-located, wherein the base station is a next generation Node B of
3GPP 5G NR.
43. A non-transitory memory medium storing program instructions,
wherein the program instructions, when executed by one or more
processors, cause the one or more processors to: send signal
quality information from a distributed unit (DU) of a base station
to a central unit (CU) of the base station, wherein the DU is
coupled to a plurality of antennas, wherein the signal quality
information is related to one or more signal quality measurements.
Description
PRIORITY CLAIM
[0001] This application claims priority under 35 USC 119(e) to U.S.
Provisional Patent Application Ser. No. 62,543,864, filed Aug. 10,
2017 [reference number AA2798-Z (4884.969PRV)], which is
incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] Embodiments pertain to wireless communications. Some
embodiments relate to cellular communication networks including
3GPP (Third Generation Partnership Project) networks, 3GPP LTE
(Long Term Evolution) networks, 3GPP LTE-A (LTE Advanced) networks,
New Radio (NR) networks, and 5G networks, although the scope of the
embodiments is not limited in this respect. Some embodiments
related to disaggregated Generation Node-Bs (gNBs). Some
embodiments relate to precoding, including split precoding between
components. Some embodiments relate to prefiltering, including
split prefiltering between components.
BACKGROUND
[0003] Base stations and mobile devices operating in a cellular
network may exchange data. Functionality related to various
protocol layers may be implemented in a base station to support
communication with mobile devices. In an example scenario, a large
number of mobile devices may communicate with the base station.
[0004] In another example scenario, performance targets for a
mobile device, such as latency, delay and/or other, may be
challenging for the base station to meet. Accordingly, there is a
general need for methods and systems to implement communication
between the base station and the mobile devices in these and other
scenarios.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1A is a functional diagram of an example network in
accordance with some embodiments;
[0006] FIG. 1B is a functional diagram of another example network
in accordance with some embodiments;
[0007] FIG. 2 illustrates a block diagram of an example machine in
accordance with some embodiments;
[0008] FIG. 3 illustrates a user device in accordance with some
aspects;
[0009] FIG. 4 illustrates a base station in accordance with some
aspects;
[0010] FIG. 5 illustrates an exemplary communication circuitry
according to some aspects;
[0011] FIG. 6 illustrates the operation of a method of
communication in accordance with some embodiments;
[0012] FIG. 7 illustrates the operation of another method of
communication in accordance with some embodiments;
[0013] FIG. 8 illustrates the operation of another method of
communication in accordance with some embodiments;
[0014] FIG. 9 illustrates example operations in accordance with
some embodiments; and
[0015] FIG. 10 illustrates additional example operations in
accordance with some embodiments.
DETAILED DESCRIPTION
[0016] The following description and the drawings sufficiently
illustrate specific embodiments to enable those skilled in the art
to practice them. Other embodiments may incorporate structural,
logical, electrical, process, and other changes. Portions and
features of some embodiments may be included in, or substituted
for, those of other embodiments. Embodiments set forth in the
claims encompass all available equivalents of those claims.
[0017] FIG. 1A is a functional diagram of an example network in
accordance with some embodiments. FIG. 1B is a functional diagram
of another example network in accordance with some embodiments. In
references herein, "FIG. 1" may include FIG. 1A and FIG. 1B. In
some embodiments, the network 100 may be a Third Generation
Partnership Project (3GPP) network. In some embodiments, the
network 150 may be a 3GPP network. In a non-limiting example, the
network 150 may be a new radio (NR) network. It should be noted
that embodiments are not limited to usage of 3GPP networks,
however, as other networks may be used in some embodiments. As an
example, a Fifth Generation (5G) network may be used in some cases.
As another example, a New Radio (NR) network may be used in some
cases. As another example, a wireless local area network (WLAN) may
be used in some cases. Embodiments are not limited to these example
networks, however, as other networks may be used in some
embodiments. In some embodiments, a network may include one or more
components shown in FIG. 1A. Some embodiments may not necessarily
include all components shown in FIG. 1A, and some embodiments may
include additional components not shown in FIG. 1A. In some
embodiments, a network may include one or more components shown in
FIG. 1B. Some embodiments may not necessarily include all
components shown in FIG. 1B, and some embodiments may include
additional components not shown in FIG. 1B. In some embodiments, a
network may include one or more components shown in FIG. 1A and one
or more components shown in FIG. 1B. In some embodiments, a network
may include one or more components shown in FIG. 1A, one or more
components shown in FIG. 1B and one or more additional
components.
[0018] The network 100 may comprise a radio access network (RAN)
101 and the core network 120 (e.g., shown as an evolved packet core
(EPC)) coupled together through an S1 interface 115. For
convenience and brevity sake, only a portion of the core network
120, as well as the RAN 101, is shown. In a non-limiting example,
the RAN 101 may be an evolved universal terrestrial radio access
network (E-UTRAN). In another non-limiting example, the RAN 101 may
include one or more components of a New Radio (NR) network. In
another non-limiting example, the RAN 101 may include one or more
components of an E-UTRAN and one or more components of another
network (including but not limited to an NR network).
[0019] The core network 120 may include a mobility management
entity (MME) 122, a serving gateway (serving GW) 124, and packet
data network gateway (PDN GW) 126. In some embodiments, the network
100 may include (and/or support) one or more Evolved Node-B's
(eNBs) 104 (which may operate as base stations) for communicating
with User Equipment (UE) 102. The eNBs 104 may include macro eNBs
and low power (LP) eNBs, in some embodiments.
[0020] In some embodiments, the network 100 may include (and/or
support) one or more Next Generation Node-B's (gNBs) 105. In some
embodiments, one or more eNBs 104 may be configured to operate as
gNBs 105. Embodiments are not Limited to the number of eNBs 104
shown in FIG. 1A or to the number of gNBs 105 shown in FIG. 1A. In
some embodiments, the network 100 may not necessarily include eNBs
104. Embodiments are also not limited to the connectivity of
components shown in FIG. 1A.
[0021] It should be noted that references herein to an eNB 104 or
to a gNB 105 are not limiting. In some embodiments, one or more
operations, methods and/or techniques (such as those described
herein) may be practiced by a base station component (and/or other
component), including but not limited to a gNB 105, an eNB 104, a
serving cell, a transmit receive point (TRP) and/or other. In some
embodiments, the base station component may be configured to
operate in accordance with a New Radio (NR) protocol and/or NR
standard, although the scope of embodiments is not limited in this
respect. In some embodiments, the base station component may be
configured to operate in accordance with a Fifth Generation (5G)
protocol and/or 5G standard, although the scope of embodiments is
not limited in this respect.
[0022] In some embodiments, the gNB 105 may include multiple
components. In a non-limiting example shown in 130, the gNB 105 may
comprise one or more of: a gNB central unit (gNB-CU) 106, a gNB
distributed unit (gNB-DU) 108 and/or other component(s). The gNB-CU
106 and the gNB-DU 108 may communicate over the F1 interface 110,
although the scope of embodiments is not limited in this respect.
It should be noted that the gNB-CU 106 may be referred to herein as
the CU 106, in some cases. In addition, the gNB-DU 108 may be
referred to herein as the DU 108, in some cases.
[0023] In some embodiments, the gNB-CU 106 and the gNB-DU 108 may
be part of a disaggregated gNB 105. The gNB-CU 106 and the gNB-DU
108 may be co-located, in some embodiments. The gNB-CU 106 and the
gNB-DU 108 may not necessarily be co-located, in some
embodiments.
[0024] The scope of embodiments is not limited to arrangements in
which the gNB-CU 106 and the gNB-DU 108 are part of a disaggregated
gNB 105, however. In some embodiments, one or more of the
techniques, operations and/or methods described herein may be
practiced by a gNB-CU 106 and/or gNB-DU 108 that may not
necessarily be included in a disaggregated gNB 105. In some
embodiments, one or more of the techniques, operations and/or
methods described herein may be practiced by a gNB 105 that may not
necessarily be a disaggregated gNB 105. In some embodiments, one or
more of the techniques, operations and/or methods described herein
may be practiced by a gNB 105 that may not necessarily include the
gNB-CU 106 or gNB-DU 108.
[0025] References herein to communication between the gNB 105 and
another component (such as the UE 102, MME 122, SGW 124 and/or
other) are not limiting. In some embodiments, such communication
may be performed between the component (such as the UE 102, MME
122, SGW 124 and/or other) and one or more of: the gNB-CU 106 and
the gNB-DU 108. References herein to an operation, technique and/or
method performed by the gNB 105 are not limiting. In some
embodiments, such an operation, technique and/or method may be
performed by the gNB-CU 106 and/or the gNB-DU 108.
[0026] In some embodiments, one or more of the UEs 102, gNBs 105,
gNB-CU 106, gNB-DU 108 and/or eNBs 104 may be configured to operate
in accordance with an NR protocol and/or NR techniques. References
to a UE 102, eNB 104, gNB-CU 106, gNB-DU 108 and/or gNB 105 as part
of descriptions herein are not limiting. For instance, descriptions
of one or more operations, techniques and/or methods practiced by a
gNB 105 are not limiting. In some embodiments, one or more of those
operations, techniques and/or methods may be practiced by an eNB
104 and/or other base station component.
[0027] In some embodiments, the UE 102 may transmit signals (data,
control and/or other) to the gNB 105, and may receive signals
(data, control and/or other) from the gNB 105. In some embodiments,
the UE 102 may transmit signals (data, control and/or other) to the
eNB 104, and may receive signals (data, control and/or other) from
the eNB 104. These embodiments will be described in more detail
below. In some embodiments, the UE 102 may transmit signals to a
component of a disaggregated gNB 105 (such as the gNB-DU 108 and/or
other). In some embodiments, the UE 102 may receive signals from a
component of a disaggregated gNB 105 (such as the gNB-DU 108 and/or
other).
[0028] The MME 122 is similar in function to the control plane of
legacy Serving GPRS Support Nodes (SGSN). The MME 122 manages
mobility aspects in access such as gateway selection and tracking
area list management. The serving GW 124 terminates the interface
toward the RAN 101, and routes data packets between the RAN 101 and
the core network 120. In addition, it may be a local mobility
anchor point for inter-eNB handovers and also may provide an anchor
for inter-3GPP mobility. Other responsibilities may include lawful
intercept, charging, and some policy enforcement. The serving GW
124 and the MME 122 may be implemented in one physical node or
separate physical nodes. The PDN GW 126 terminates an SGi interface
toward the packet data network (PDN). The PUN GW 126 routes data
packets between the EPC 120 and the external PDN, and may be a key
node for policy enforcement and charging data collection. It may
also provide an anchor point for mobility with non-LTE accesses.
The external PDN can be any kind of IP network, as well as an IP
Multimedia Subsystem (IMS) domain. The PDN GW 126 and the serving
GW 124 may be implemented in one physical node or separated
physical nodes.
[0029] In some embodiments, the eNBs 104 (macro and micro)
terminate the air interface protocol and may be the first point of
contact for a UE 102. In some embodiments, an eNB 104 may fulfill
various logical functions for the network 100, including but not
limited to RNC (radio network controller functions) such as radio
bearer management, uplink and downlink dynamic radio resource
management and data packet scheduling, and mobility management.
[0030] In some embodiments, UEs 102 may be configured to
communicate Orthogonal Frequency Division Multiplexing (OFDM)
communication signals with an eNB 104 and/or gNB 105 over a
multicarrier communication channel in accordance with an Orthogonal
Frequency Division Multiple Access (OFDMA) communication technique.
In some embodiments, eNBs 104 and/or gNBs 105 may be configured to
communicate OFDM communication signals with a UE 102 over a
multicarrier communication channel in accordance with an OFDMA
communication technique. The OFDM signals may comprise a plurality
of orthogonal subcarriers.
[0031] The S1 interface 115 is the interface that separates the RAN
101 and the EPC 120. It may be split into two parts: the S1-U,
which carries traffic data between the eNBs 104 and the serving GW
124, and the S1-MME, which is a signaling interface between the
eNBs 104 and the MME 122. The X2 interface is the interface between
eNBs 104. The X2 interface comprises two parts, the X2-C and X2-U.
The X2-C is the control plane interface between the eNBs 104, while
the X2-U is the user plane interface between the eNBs 104.
[0032] In some embodiments, similar functionality and/or
connectivity described for the eNB 104 may be used for the gNB 105,
although the scope of embodiments is not limited in this respect.
In a non-limiting example, the S interface 115 (and/or similar
interface) may be split into two parts: the S1-U, which carries
traffic data between the gNBs 105 and the serving GW 124, and the
S1-MME, which is a signaling interface between the gNBs 104 and the
MME 122. The X2 interface (and/or similar interface) may enable
communication between eNBs 104, communication between gNBs 105
and/or communication between an eNB 104 and a gNB 105.
[0033] With cellular networks, LP cells are typically used to
extend coverage to indoor areas where outdoor signals do not reach
well, or to add network capacity in areas with very dense phone
usage, such as train stations. As used herein, the term low power
(LP) eNB refers to any suitable relatively low power eNB for
implementing a narrower cell (narrower than a macro cell) such as a
femtocell, a picocell, or a micro cell. Femtocell eNBs are
typically provided by a mobile network operator to its residential
or enterprise customers. A femtocell is typically the size of a
residential gateway or smaller and generally connects to the user's
broadband line. Once plugged in, the femtocell connects to the
mobile operator's mobile network and provides extra coverage in a
range of typically 30 to 50 meters for residential femtocells.
Thus, a LP eNB might be a femtocell eNB since it is coupled through
the PDN GW 126. Similarly, a picocell is a wireless communication
system typically covering a small area, such as in-building
(offices, shopping malls, train stations, etc.), or more recently
in-aircraft. A picocell eNB can generally connect through the X2
link to another eNB such as a macro eNB through its base station
controller (BSC) functionality. Thus, LP eNB may be implemented
with a picocell eNB since it is coupled to a macro eNB via an X2
interface. Picocell eNBs or other LP eNBs may incorporate some or
all functionality of a macro eNB. In some cases, this may be
referred to as an access point base station or enterprise
femtocell. In some embodiments, various types of gNBs 105 may be
used, including but not limited to one or more of the eNB types
described above.
[0034] In some embodiments, the network 150 may include one or more
components configured to operate in accordance with one or more
3GPP standards, including but not limited to an NR standard. The
network 150 shown in FIG. 1B may include a next generation RAN
(NG-RAN) 155, which may include one or more gNBs 105. In some
embodiments, the network 150 may include the E-UTRAN 160, which may
include one or more eNBs. The E-UTRAN 160 may be similar to the RAN
101 described herein, although the scope of embodiments is not
limited in this respect.
[0035] In some embodiments, the network 150 may include the MME
165. The MME 165 may be similar to the MME 122 described herein,
although the scope of embodiments is not limited in this respect.
The MME 165 may perform one or more operations or functionality
similar to those described herein regarding the MME 122, although
the scope of embodiments is not limited in this respect.
[0036] In some embodiments, the network 150 may include the SGW
170. The SGW 170 may be similar to the SGW 124 described herein,
although the scope of embodiments is not limited in this respect.
The SGW 170 may perform one or more operations or functionality
similar to those described herein regarding the SGW 124, although
the scope of embodiments is not limited in this respect.
[0037] In some embodiments, the network 150 may include
component(s) and/or module(s) for functionality for a user plane
function (UPF) and user plane functionality for PGW (PGW-U), as
indicated by 175. In some embodiments, the network 150 may include
component(s) and/or module(s) for functionality for a session
management function (SMF) and control plane functionality for PGW
(PGW-C), as indicated by 180. In some embodiments, the component(s)
and/or module(s) indicated by 175 and/or 180 may be similar to the
PGW 126 described herein, although the scope of embodiments is not
limited in this respect. The component(s) and/or module(s)
indicated by 175 and/or 180 may perform one or more operations or
functionality similar to those described herein regarding the PGW
126, although the scope of embodiments is not limited in this
respect. One or both of the, components 170, 172 may perform at
least a portion of the functionality described herein for the PGW
126, although the scope of embodiments is not limited in this
respect.
[0038] Embodiments are not limited to the number or type of
components shown in FIG. 1B. Embodiments are also not limited to
the connectivity of components shown in FIG. 1B.
[0039] In some embodiments, a downlink resource grid may be used
for downlink transmissions from an eNB 104 to a UE 102, while
uplink transmission from the UE 102 to the eNB 104 may utilize
similar techniques. In some embodiments, a downlink resource grid
may be used for downlink transmissions from a gNB 105 to a UE 102,
while uplink transmission from the UE 102 to the gNB 105 may
utilize similar techniques. The grid may be a time-frequency grid,
called a resource grid or time-frequency resource grid, which is
the physical resource in the downlink in each slot. Such a
time-frequency plane representation is a common practice for OFDM
systems, which makes it intuitive for radio resource allocation.
Each column and each row of the resource grid correspond to one
OFDM symbol and one OFDM subcarrier, respectively. The duration of
the resource grid in the time domain corresponds to one slot in a
radio frame. The smallest time-frequency unit in a resource grid is
denoted as a resource element (RE). There are several different
physical downlink channels that are conveyed using such resource
blocks. With particular relevance to this disclosure, two of these
physical downlink channels are the physical downlink shared channel
and the physical down link control channel.
[0040] As used herein, the term "circuitry" may refer to, be part
of, or include an Application Specific Integrated Circuit (ASIC),
an electronic circuit, a processor (shared, dedicated, or group),
and/or memory (shared, dedicated, or group) that execute one or
more software or firmware programs, a combinational logic circuit,
and/or other suitable hardware components that provide the
described functionality. In some embodiments, the circuitry may be
implemented in, or functions associated with the circuitry may be
implemented by, one or more software or firmware modules. In some
embodiments, circuitry may include logic, at least partially
operable in hardware. Embodiments described herein may be
implemented into a system using any suitably configured hardware
and/or software.
[0041] FIG. 2 illustrates a block diagram of an example machine in
accordance with some embodiments. The machine 200 is an example
machine upon which any one or more of the techniques and/or
methodologies discussed herein may be performed. In alternative
embodiments, the machine 200 may operate as a standalone device or
may be connected (e.g., networked) to other machines. In a
networked deployment, the machine 200 may operate in the capacity
of a server machine, a client machine, or both in server-client
network environments. In an example, the machine 200 may act as a
peer machine in peer-to-peer (P2P) (or other distributed) network
environment. The machine 200 may be a UE 102, eNB 104, gNB 105,
gNB-CU 106, gNB-DU 108, access point (AP), station (STA), user,
device, mobile device, base station, personal computer (PC), a
tablet PC, a set-top box (STB), a personal digital assistant (PDA),
a mobile telephone, a smart phone, a web appliance, a network
router, switch or bridge, or any machine capable of executing
instructions (sequential or otherwise) that specify actions to be
taken by that machine. Further, while only a single machine is
illustrated, the term "machine" shall also be taken to include any
collection of machines that individually or jointly execute a set
(or multiple sets) of instructions to perform any one or more of
the methodologies discussed herein, such as cloud computing,
software as a service (SaaS), other computer cluster
configurations.
[0042] Examples as described herein, may include, or may operate
on, logic or a number of components, modules, or mechanisms.
Modules are tangible entities (e.g., hardware) capable of
performing specified operations and may be configured or arranged
in a certain manner. In an example, circuits may be arranged (e.g.,
internally or with respect to external entities such as other
circuits) in a specified manner as a module. In an example, the
whole or part of one or more computer systems (e.g., a standalone,
client or server computer system) or one or more hardware
processors may be configured by firmware or software (e.g.,
instructions, an application portion, or an application) as a
module that operates to perform specified operations. In an
example, the software may reside on a machine readable medium. In
an example, the software, when executed by the underlying hardware
of the module, causes the hardware to perform the specified
operations.
[0043] Accordingly, the term "module" is understood to encompass a
tangible entity, be that an entity that is physically constructed,
specifically configured (e.g., hardwired), or temporarily (e.g.,
transitorily) configured (e.g., programmed) to operate in a
specified manner or to perform pan or all of any operation
described herein. Considering examples in which modules are
temporarily configured, each of the modules need not be
instantiated at any one moment in time. For example, where the
modules comprise a general-purpose hardware processor configured
using software, the general-purpose hardware processor may be
configured as respective different nodules at different times.
Software may accordingly configure a hardware processor, for
example, to constitute a particular module at one instance of time
and to constitute a different module at a different instance of
time.
[0044] The machine (e.g., computer system) 200 may include a
hardware processor 202 (e.g., a central processing unit (CPU), a
graphics processing unit (GPU), a hardware processor core, or any
combination thereof), a main memory 204 and a static memory 206,
some or all of which may communicate with each other via an
interlink (e.g., bus) 208. The machine 200 may further include a
display unit 210, an alphanumeric input device 212 (e.g., a
keyboard), and a user interface (UI) navigation device 214 (e.g., a
mouse). In an example, the display unit 210, input device 212 and
UI navigation device 214 may be a touch screen display. The machine
200 may additionally include a storage device (e.g., drive unit)
216, a signal generation device 218 (e.g., a speaker), a network
interface device 220, and one or more sensors 221, such as a global
positioning system (GPS) sensor, compass, accelerometer, or other
sensor. The machine 200 may include an output controller 228, such
as a serial (e.g., universal serial bus (USB), parallel, or other
wired or wireless (e.g., infrared (IR), near field communication
(NFC), etc.) connection to communicate or control one or more
peripheral devices (e.g., a printer, card reader, etc.).
[0045] The storage device 216 may include a machine readable medium
222 on which is stored one or more sets of data structures or
instructions 224 (e.g., software) embodying or utilized by any one
or more of the techniques or functions described herein. The
instructions 224 may also reside, completely or at least partially,
within the main memory 204, within static memory 206, or within the
hardware processor 202 during execution thereof by the machine 200.
In an example, one or any combination of the hardware processor
202, the main memory 204, the static memory 206, or the storage
device 216 may constitute machine readable media. In some
embodiments, the machine readable medium may be or may include a
non-transitory computer-readable storage medium. In some
embodiments, the machine readable medium may be or may include a
computer-readable storage medium.
[0046] While the machine readable medium 222 is illustrated as a
single medium, the term "machine readable medium" may include a
single medium or multiple media (e.g., a centralized or distributed
database, and/or associated caches and servers) configured to store
the one or more instructions 224. The term "machine readable
medium" may include any medium that is capable of storing,
encoding, or carrying instructions for execution by the machine 200
and that cause the machine 200 to perform any one or more of the
techniques of the present disclosure, or that is capable of
storing, encoding or carrying data structures used by or associated
with such instructions. Non-limiting machine readable medium
examples may include solid-state memories, and optical and magnetic
media. Specific examples of machine readable media may include:
non-volatile memory, such as semiconductor memory devices
Electrically Programmable Read-Only Memory (EPROM), Electrically
Erasable Programmable Read-Only Memory, (EEPROM)) and flash memory
devices; magnetic disks, such as internal hard disks and removable
disks; magneto-optical disks; Random Access Memory (RAM); and
CD-ROM and DVD-ROM disks. In some examples, machine readable media
may include non-transitory machine readable media. In some
examples, machine readable media may include machine readable media
that is not a transitory propagating signal.
[0047] The instructions 224 may further be transmitted or received
over a communications network 226 using a transmission medium via
the network interface device 220 utilizing any one of a number of
transfer protocols (e.g., frame relay, internet protocol (LP),
transmission control protocol (TCP), user datagram protocol (UDP),
hypertext transfer protocol (HTTP), etc.). Example communication
networks may include a local area network (LAN), a wide area
network (WAN), a packet data network (e.g., the Internet), mobile
telephone networks (e.g., cellular networks), Plain Old Telephone
(POTS) networks, and wireless data networks (e.g., Institute of
Electrical and Electronics Engineers (IEEE) 802.11 family of
standards known as Wi-Fi.RTM., IEEE 802.16 family of standards
known as WiMax.RTM.), IEEE 802.15.4 family of standards, a Long
Term Evolution (LTE) family of standards, a Universal Mobile
Telecommunications System (UMTS) family of standards, peer-to-peer
(P2P) networks, among others. In an example, the network interface
device 220 may include one or more physical jacks (e.g., Ethernet,
coaxial, or phone jacks) or one or more antennas to connect to the
communications network 226. In an example, the network interface
device 220 may include a plurality of antennas to wirelessly
communicate using at least one of single-input multiple-output
(SIMO), multiple-input multiple-output (MIMO), or multiple-input
single-output (MISO) techniques. In some examples, the network
interface device 220 may wirelessly communicate using Multiple User
MIMO techniques. The term "transmission medium" shall be taken to
include any intangible medium that is capable of storing, encoding
or carrying instructions for execution by the machine 200, and
includes digital or analog communications signals or other
intangible medium to facilitate communication of such software.
[0048] FIG. 3 illustrates a user device in accordance with some
aspects. In some embodiments, the user device 300 may be a mobile
device. In some embodiments, the user device 300 may be or may be
configured to operate as a User Equipment (UE). In some
embodiments, the user device 300 may be arranged to operate in
accordance with a new radio (NR) protocol. In some embodiments, the
user device 300 may be arranged to operate in accordance with a
Third Generation Partnership Protocol (3GPP) protocol. The user
device 300 may be suitable for use as a UE 102 as depicted in FIG.
1, in some embodiments. It should be rioted that in some
embodiments, a UE, an apparatus of a UE, a user device or an
apparatus of a user device may include one or more of the
components shown in one or more of FIGS. 2, 3, and 5. In some
embodiments, such a UE, user device and/or apparatus may include
one or more additional components.
[0049] In some aspects, the user device 300 may include an
application processor 305, baseband processor 310 (also referred to
as a baseband module), radio front end module (RFEM) 315, memory
320, connectivity module 325, near field communication (NFC)
controller 330, audio driver 335, camera driver 340, touch screen
345, display driver 350, sensors 355, removable memory 360, power
management integrated circuit (PMIC) 365 and smart battery 370. In
some aspects, the user device 300 may be a User Equipment (UE).
[0050] In some aspects, application processor 305 may include, for
example, one or more CPU cores and one or more of cache memory, low
drop-out voltage regulators (LDOs), interrupt controllers, serial
interfaces such as serial peripheral interface (SPI),
inter-integrated circuit (I.sup.2C) or universal programmable
serial interface module, real time clock (RTC), timer-counters
including interval and watchdog timers, general purpose
input-output (IO), memory card controllers such as secure
digital/multi-media card (SD/MMC) or similar, universal serial bus
(USB) interfaces, mobile industry processor interface (MIPI)
interfaces and Joint Test Access Group (JTAG) test access
ports.
[0051] In some aspects, baseband module 310 may be implemented, for
example, as a solder-down substrate including one or more
integrated circuits, a single packaged integrated circuit soldered
to a main circuit board, and/or a multi-chip module containing two
or more integrated circuits.
[0052] FIG. 4 illustrates a base station in accordance with some
aspects. In some embodiments, the base station 400 may be or may be
configured to operate as an Evolved Node-B (eNB). In some
embodiments, the base station 400 may be or may be configured to
operate as a Next Generation Node-B (gNB). In some embodiments, the
base station 400 may be arranged to operate in accordance with a
new radio (NR) protocol. In some embodiments, the base station 400
may be arranged to operate in accordance with a Third Generation
Partnership Protocol (3GPP) protocol. It should be noted that in
some embodiments, the base station 400 may be a stationary
non-mobile device. The base station 400 may be suitable for use as
an eNB 104 as depicted in FIG. 1, in some embodiments. The base
station 400 may be suitable for use as a gNB 105 as depicted in
FIG. 1, in some embodiments. It should be noted that in some
embodiments, an eNB, an apparatus of an eNB, a gNB, an apparatus of
a gNB, a gNB-CU 106, an apparatus of a gNB-CU 106, a gNB-DU 108, an
apparatus of a gNB-DU 108, a base station and/or an apparatus of a
base station may include one or more of the components shown in one
or more of FIGS. 2, 4, and 5. In some embodiments, such an eNB,
gNB, gNB-CU, a gNB-DU, base station and/or apparatus may include
one or more additional components.
[0053] FIG. 4 illustrates a base station or infrastructure
equipment radio head 400 in accordance with some aspects. The base
station 400 may include one or more of application processor 405,
baseband modules 410, one or more radio front end modules 415,
memory 420, power management circuitry 425, power tee circuitry
430, network controller 435, network interface connector 440,
satellite navigation receiver module 445, and user interface 450.
In some aspects, the base station 400 may be an Evolved Node-B
(eNB), which may be arranged to operate in accordance with a 3GPP
protocol, new radio (NR) protocol and/or Fifth Generation (5G)
protocol. In some aspects, the base station 400 may be a Next
Generation Node-B (gNB), which may be arranged to operate in
accordance with a 3GPP protocol, new radio (NR) protocol and/or
Fifth Generation (5G) protocol.
[0054] In some aspects, application processor 405 may include one
or more CPU cores and one or more of cache memory, low drop-out
voltage regulators (LDOs), interrupt controllers, serial interfaces
such as SPI, I.sup.2C or universal programmable serial interface
module, real time clock (RTC), tinier-counters including interval
and watchdog timers, general purpose IO, memory card controllers
such as SD/MMC or similar, USB interfaces, MIPI interfaces and
Joint Test Access Group (JTAG) test access ports.
[0055] In some aspects, baseband processor 410 may be implemented,
for example, as a solder-down substrate including one or more
integrated circuits, a single packaged integrated circuit soldered
to a main circuit board or a multi-chip module containing two or
more integrated circuits.
[0056] In some aspects, memory 420 may include one or more of
volatile memory including dynamic random access memory (DRAM)
and/or synchronous dynamic random access memory (SDRAM), and
nonvolatile memory (NVM) including high-speed electrically erasable
memory (commonly referred to as Flash memory), phase change random
access memory (PRAM), magneto-resistive random access memory (MRAM)
and/or a three-dimensional cross-point memory. Memory 420 may be
implemented as one or more of solder down packaged integrated
circuits, socketed memory modules and plug-in memory cards.
[0057] In some aspects, power management integrated circuitry 425
may include one or more of voltage regulators, surge protectors,
power alarm detection circuitry and one or more backup power
sources such as a battery or capacitor. Power alarm detection
circuitry may detect one or more of brown out (under-voltage) and
surge (over-voltage) conditions.
[0058] In some aspects, power tee circuitry 430 may provide for
electrical power drawn from a network cable to provide both power
supply and data connectivity to the base station 400 using a single
cable. In some aspects, network controller 435 may provide
connectivity to a network using a standard network interface
protocol such as Ethernet. Network connectivity may be provided
using a physical connection which is one of electrical (commonly
referred to as copper interconnect), optical or wireless.
[0059] In some aspects, satellite navigation receiver module 445
may include circuitry to receive and decode signals transmitted by
one or more navigation satellite constellations such as the global
positioning system (GPS), Globalnaya Navigatsionnaya Sputnikovaya
Sistema (GLONASS), Galileo and/or BeiDou. The receiver 445 may
provide data to application processor 405 which may include one or
more of position data or time data. Application processor 405 may
use time data to synchronize operations with other radio base
stations. In some aspects, user interface 450 may include one or
more of physical or virtual buttons, such as a reset button, one or
more indicators such as light emitting diodes (LEDs) and a display
screen.
[0060] FIG. 5 illustrates an exemplary communication circuitry
according to some aspects. Circuitry 500 is alternatively grouped
according to functions. Components as shown in 500 are shown here
for illustrative purposes and may include other components not
shown here in FIG. 5. In some aspects, the communication circuitry
500 may be used for millimeter wave communication, although aspects
are not limited to millimeter wave communication. Communication at
any suitable frequency may be performed by the communication
circuitry 500 in some aspects.
[0061] It should be noted that a device, such as a UE 102, eNB 104,
gNB 105, gNB-CU 106, gNB-DU 108, the user device 300, the base
station 400, the machine 200 and/or other device may include one or
more components of the communication circuitry 500, in some
aspects.
[0062] The communication circuitry 500 may include protocol
processing circuitry 505, which may implement one or more of medium
access control (MAC), radio link control (RLC), packet data
convergence protocol (PDCP), radio resource control (RRC) and
non-access stratum (NAS) functions. Protocol processing circuitry
505 may include one or more processing cores (not shown) to execute
instructions and one or more memory structures (not shown) to store
program and data information.
[0063] The communication circuitry 500 may further include digital
baseband circuitry 510, which may implement physical layer (PHY)
functions including one or more of hybrid automatic repeat request
(HARQ) functions, scrambling and/or descrambling, coding and/or
decoding, layer mapping and/or de-mapping, modulation symbol
mapping, received symbol and/or bit metric determination,
multi-antenna port pre-coding and/or decoding which may include one
or more of space-time, space-frequency or spatial coding, reference
signal generation and/or detection, preamble sequence generation
and/or decoding, synchronization sequence generation and/or
detection, control channel signal blind decoding, and other related
functions.
[0064] The communication circuitry 500 may further include transmit
circuitry 515, receive circuitry 520 and/or antenna array circuitry
530. The communication circuitry 500 may further include radio
frequency (RF) circuitry 525. In an aspect of the disclosure, RF
circuitry 525 may include multiple parallel RF chains for one or
more of transmit or receive functions, each connected to one or
more antennas of the antenna array 530.
[0065] In an aspect of the disclosure, protocol processing
circuitry 505 may include one or more instances of control
circuitry (not shown) to provide control functions for one or more
of digital baseband circuitry 510, transmit circuitry 515, receive
circuitry 520, and/or radio frequency circuitry 525.
[0066] In some embodiments, processing circuitry may perform one or
more operations described herein and/or other operation(s). In a
non-limiting example, the processing circuitry may include one or
more components such as the processor 202, application processor
305, baseband module 310, application processor 405, baseband
module 410, protocol processing circuitry 505, digital baseband
circuitry 510, similar component(s) and/or other component(s).
[0067] In some embodiments, a transceiver may transmit one or more
elements (including but not limited to those described herein)
and/or receive one or more elements (including but not limited to
those described herein). In a non-limiting example, the transceiver
may include one or more components such as the radio front end
module 315, radio front end module 415, transmit circuitry 515,
receive circuitry 520, radio frequency circuitry 525, similar
component(s) and/or other component(s).
[0068] One or more antennas (such as 230, 312, 412, 530 and/or
others) may comprise one or more directional or omnidirectional
antennas, including, for example, dipole antennas, monopole
antennas, patch antennas, loop antennas, microstrip antennas or
other types of antennas suitable for transmission of RF signals. In
some multiple-input multiple-output (MIMO) embodiments, one or more
of the antennas (such as 230, 312, 412, 530 and/or others) may be
effectively separated to take advantage of spatial diversity and
the different channel characteristics that may result.
[0069] In some embodiments, the UE 102, eNB 104, gNB 105, gNB-CU
106, gNB-DU 108, user device 300, base station 400, machine 200
and/or other device described herein may be a mobile device and/or
portable wireless communication device, such as a personal digital
assistant (PDA), a laptop or portable computer with wireless
communication capability, a web tablet, a wireless telephone, a
smartphone, a wireless headset, a pager, an instant messaging
device, a digital camera, an access point, a television, a wearable
device such as a medical device (e.g., a heart rate monitor, a
blood pressure monitor, etc.), or other device that may receive
and/or transmit information wirelessly. In some embodiments, the UE
102, eNB 104, gNB 105, gNB-CU 106, gNB-DU 108, user device 300,
base station 400, machine 200 and/or other device described herein
may be configured to operate in accordance with 3GPP standards,
although the scope of the embodiments is not limited in this
respect. In some embodiments, the UE 102, eNB 104, gNB 105, gNB-CU
106, gNB-DU 108, user device 300, base station 400, machine 200
and/or other device described herein may be configured to operate
in accordance with new radio (NR) standards, although the scope of
the embodiments is not limited in this respect. In some
embodiments, the UE 102, eNB 104, gNB 105, gNB-CU 106, gNB-DU 108,
user device 300, base station 400, machine 200 and/or other device
described herein may be configured to operate according to other
protocols or standards, including IEEE 802.11 or other IEEE
standards. In some embodiments, the UE 102, eNB 104, gNB 105,
gNB-CU 106, gNB-DU 108, user device 300, base station 400, machine
200 and/or other device described herein may include one or more of
a keyboard, a display, a non-volatile memory port, multiple
antennas, a graphics processor, an application processor, speakers,
and other mobile device elements. The display may be an LCD screen
including a touch screen.
[0070] Although the UE 102, eNB 104, gNB 105, gNB-CU 106, gNB-DU
108, user device 300, base station 400, machine 200 and/or other
device described herein may each be illustrated as having several
separate functional elements, one or more of the functional
elements may be combined and may be implemented by combinations of
software-configured elements, such as processing elements including
digital signal processors (DSPs), and/or other hardware elements.
For example, some elements may comprise one or more
microprocessors, DSPs, field-programmable gate arrays (FPGAs),
application specific integrated circuits (ASICs), radio-frequency
integrated circuits (RFICs) and combinations of various hardware
and logic circuitry for performing at least the functions described
herein. In some embodiments, the functional elements may refer to
one or more processes operating on one or more processing
elements.
[0071] Embodiments may be implemented in one or a combination of
hardware, firmware and software. Embodiments may also be
implemented as instructions stored on a computer-readable storage
device, which may be read and executed by at least one processor to
perform the operations described herein. A computer-readable
storage device may include any non-transitory mechanism for storing
information in a form readable by a machine (e.g., a computer). For
example, a computer-readable storage device may include read-only
memory (ROM), random-access memory (RAM), magnetic disk storage
media, optical storage media, flash-memory devices, and other
storage devices and media. Some embodiments may include one or more
processors and may be configured with instructions stored on a
computer-readable storage device.
[0072] It should be noted that in some embodiments, an apparatus of
the UE 102, eNB 104, gNB 105, gNB-CU 106, gNB-DU 108, machine 200,
user device 300 and/or base station 400 may include various
components shown in FIGS. 2-5. Accordingly, techniques and
operations described herein that refer to the UE 102 may be
applicable to an apparatus of a UE. In addition, techniques and
operations described herein that refer to the eNB 104 may be
applicable to an apparatus of an eNB. In addition, techniques and
operations described herein that refer to the gNB 105 may be
applicable to an apparatus of a gNB. In addition, techniques and
operations described herein that refer to the gNB-CU 106, may be
applicable to an apparatus of a gNB-CU. In addition, techniques and
operations described herein that refer to the gNB-DU 108 may be
applicable to an apparatus of a gNB-DU,
[0073] It should be noted that some of the descriptions herein may
refer to performance of operations, methods and/or techniques by
components such as the gNB 105, the gNB-CU 106, and the gNB-DU 108.
Such references are not limiting, however. For instance,
descriptions herein may refer to performance of an operation by one
of those components. In some embodiments, one of the other
components may perform the same operation, a similar operation, a
related operation and/or a reciprocal operation. In a non-limiting
example, the gNB-CU 106 may perform an operation (such as
transmission of a packet), and the gNB-DU 108 may perform a
reciprocal operation (such as reception of the packet). In a
non-limiting example, the gNB-DU 108 may perform an operation (such
as transmission of a packet), and the UE 102 may perform a
reciprocal operation (such as reception of the packet).
[0074] In accordance with some embodiments, a generation node B
(gNB) 105 may be configured with logical nodes including a gNB
central unit (gNB-CU) 106 and a gNB distributed unit (gNB-DU) 108.
The gNB-CU 106 may be configured to communicate with the gNB-DU 108
over an F1 interface. The gNB 105 may determine, by the gNB-CU 106,
a first precoding matrix and a second precoding matrix for a
precoding of one or more data streams for transmission on a
plurality of antennas coupled to the gNB-DU 108. The precoding may
be in accordance with a split functionality between the gNB-CU 106
and the gNB-DU 108 that includes: precoding by the gNB-CU 106 with
the first precoding matrix, and precoding by the gNB-DU 108 with
the second precoding matrix. The gNB-CU 106 may be configured to
precode first symbols from the data streams by the first precoding
matrix to generate second symbols for transfer on the F1 interface
to the gNB-DU 108. The gNB-DU 108 may be configured to precode the
second symbols by the second precoding matrix to generate third
symbols for transmission on the antennas. These embodiments are
described in more detail below.
[0075] FIG. 6 illustrates the operation of a method of
communication in accordance with some embodiments. FIG. 7
illustrates the operation of another method of communication in
accordance with some embodiments. FIG. 8 illustrates the operation
of another method of communication in accordance with some
embodiments. It is important to note that embodiments of the
methods 600, 700, 800 may include additional or even fewer
operations or processes in comparison to what is illustrated in
FIGS. 6-8. In addition, embodiments of the methods 600, 700, 800
are not necessarily limited to the chronological order that is
shown in FIGS. 6-8. In describing the methods 600, 700, 800,
reference may be made to one or more figures, although it is
understood that the methods 600, 700, 800 may be practiced with any
other suitable systems, interfaces and components.
[0076] In some embodiments, a gNB-CU 106 may perform one or more
operations of the method 600, but embodiments are not limited to
performance of the method 600 and/or operations of it by the gNB-CU
106. In some embodiments, another device and/or component may
perform one or more operations of the method 600. In some
embodiments, another device and/or component may perform one or
more operations that may be similar to one or more operations of
the method 600. In some embodiments, another device and/or
component may perform one or more operations that may be reciprocal
to one or more operations of the method 600. In a non-limiting
example, the gNB 105 may perform an operation that may be the same
as, similar to, reciprocal to and/or related to an operation of the
method 600, in some embodiments.
[0077] In some embodiments, a gNB-DU 108 may perform one or more
operations of the method 700, but embodiments are not limited to
performance of the method 700 and/or operations of it by the gNB-DU
108. In some embodiments, another device and/or component may
perform one or more operations of the method 700. In some
embodiments, another device and/or component may perform one or
more operations that may be similar to one or more operations of
the method 700. In some embodiments, another device and/or
component may perform one or more operations that may be reciprocal
to one or more operations of the method 700. In a non-limiting
example, the gNB 105 may perform an operation that may be the same
as, similar to, reciprocal to and/or related to an operation of the
method 700, in some embodiments.
[0078] In some embodiments, a UE 102 may perform one or more
operations of the method 800, but embodiments are not limited to
performance of the method 800 and/or operations of it by the UE
102. In some embodiments, another device and/or component may
perform one or more operations of the method 800. In some
embodiments, another device and/or component may perform one or
more operations that may be similar to one or more operations of
the method 800. In some embodiments, another device and/or
component may perform one or more operations that may be reciprocal
to one or more operations of the method 800.
[0079] It should be noted that one or more operations of one of the
methods 600, 700, 800 may be the same as, similar to and/or
reciprocal to one or more operations of the other methods. For
instance, an operation of the method 600 may be the same as,
similar to and/or reciprocal to an operation of the method 700, in
some embodiments. In a non-limiting example, an operation of the
method 600 may include transmission of an element (such as a frame,
block, message and/or other) by the gNB-CU 106, and an operation of
the method 700 may include reception of a same element (and/or
similar element) by the gNB-DU 108 from the gNB-CU 106. In some
cases, descriptions of operations and techniques described as part
of one of the methods 600, 700, 800 may be relevant to one or both
of the other methods.
[0080] Discussion of various techniques and concepts regarding one
of the methods 600, 700, 800 and/or other method may be applicable
to one of the other methods, although the scope of embodiments is
not limited in this respect. Such technique and concepts may
include precoding, precoding matrixes, precoding matrix packet,
prefiltering, prefiltering matrixes, prefiltering matrix packet,
transfer on the F1 interface and/or other.
[0081] The methods 600, 700, 800 and other methods described herein
may refer to eNBs 104, gNBs 105, gNB-CUs 106, gNB-DUs 108 and/or
UEs 102 operating in accordance with 3GPP standards, 5G standards,
NR standards and/or other standards. However, embodiments are not
limited to performance of those methods by those components, and
may also be performed by other devices, such as a Wi-Fi access
point (AP) or user station (STA). In addition, the methods 600,
700, 800 and other methods described herein may be practiced by
wireless devices configured to operate in other suitable types of
wireless communication systems, including systems configured to
operate according to various IEEE standards such as IEEE 802.11.
The methods 600, 700, 800 may also be applicable to an apparatus of
a UE 102, an apparatus of an eNB 104, an apparatus of a gNB 105, an
apparatus of a gNB-CU 106, an apparatus of a gNB-DU 108 and/or an
apparatus of another device described above.
[0082] It should also be noted that embodiments are not limited by
references herein (such as in descriptions of the methods 600, 700
and 800 and/or other descriptions herein) to transmission,
reception and/or exchanging of elements such as frames, messages,
requests, indicators, signals or other elements. In some
embodiments, such an element may be generated, encoded or otherwise
processed by processing circuitry (such as by a baseband processor
included in the processing circuitry) for transmission. The
transmission may be performed by a transceiver or other component,
in some cases. In some embodiments, such an element may be decoded,
detected or otherwise processed by the processing circuitry (such
as by the baseband processor). The element may be received by a
transceiver or other component, in some cases. In some embodiments,
the processing circuitry and the transceiver may be included in a
same apparatus. The scope of embodiments is not limited in this
respect, however, as the transceiver may be separate from the
apparatus that comprises the processing circuitry, in some
embodiments.
[0083] One or more of the elements (such as messages, operations
and/or other) described herein may be included in a standard and/or
protocol, including but not limited to Third Generation Partnership
Project (3GPP), 3GPP Long Term Evolution (LTE), Fourth Generation
(4G), Fifth Generation (5G), New Radio (NR) and/or other. The scope
of embodiments is not limited to usage of elements that are
included in standards, however.
[0084] In some embodiments, the gNB 105 may be configured with
logical nodes including a gNB central unit (gNB-CU) 106 and a gNB
distributed unit (gNB-DU) 108, and the gNB-CU 106 and the gNB-DU
108 may be configured to communicate with each other over an F1
interface. The scope of embodiments is not limited in this respect,
however, as another device (such as a gNB 105 that does not
necessarily include the gNB-CU 106 and gNB-DU 108) may perform one
or more operations of the method 600 and/or other operations
described herein.
[0085] At operation 605, the gNB-CU 106 may receive information
related to one or more signal quality measurements. In some
embodiments, the information related to the signal quality
measurements may be received from the gNB-DU 108, although the
scope of embodiments is not limited in this respect. In some
embodiments, the signal quality measurements may be determined at
the UE 102. In some embodiments, the UE 102 may transmit
information related to the signal quality measurements to the
gNB-DU 108, and the gNB-DU 108 may transfer information (the
information received from the UE 102, a portion of the information
received from the UE 102, information based on the information
received from the UE 102 and/or other) to the gNB-CU 106.
[0086] Example signal quality measurements (for operation 605
and/or other operations described herein) include, but are not
limited to, received signal power, average received signal power,
signal-to-noise ratio (SNR), reference signal received power
(RSRP), reference signal received quality (RSRQ), and received
signal strength indicator (RSSI).
[0087] At operation 610, the gNB-CU 106 may determine a number of
virtual antenna ports. At operation 615, the gNB-CU 106 may
determine a first precoding matrix for downlink precoding. At
operation 620, the gNB-CU 106 may determine a second precoding
matrix for the downlink precoding.
[0088] In some embodiments, the gNB-CU 106 may determine the first
precoding matrix and the second precoding matrix for a precoding of
one or more data streams for transmission on a plurality of
antennas coupled to the gNB-DU 108. In some embodiments, the
precoding may be in accordance with a split functionality between
the gNB-CU 106 and the gNB-DU 108 that includes: precoding by the
gNB-CU 106 with the first precoding matrix, and precoding by the
gNB-DU 108 with the second precoding matrix.
[0089] In some embodiments, a number of rows of the first precoding
matrix may be equal to a number of virtual ports, a number of
columns of the first precoding matrix may be equal to a number of
the data streams, a number of rows of the second precoding matrix
may be equal to a number of the antennas coupled to the gNB-DU, and
a number of columns of the second precoding matrix may be equal to
the number of virtual ports.
[0090] In some embodiments, the gNB-CU 106 may determine the number
of virtual ports as a number that is less than the number of
antennas coupled to the gNB-DU 106. In some embodiments, the gNB-CU
106 may determine the number of virtual ports as described above to
cause a size of symbols transferred on the F1 interface from the
gNB-CU 106 to the gNB-DU 108 (or from the gNB-DU 108 to the gNB-CU
106) to be less than symbols generated, by the gNB-DU 108, for
transmission on the antennas.
[0091] In some embodiments, the gNB-CU 106 may determine the first
precoding matrix and/or the second precoding matrix based at least
partly on the one or more signal quality measurements. In some
embodiments, the gNB-CU 16 may perform one or more of: select the
first precoding matrix from first candidate precoding matrixes; and
select the second precoding matrix from second candidate precoding
matrixes.
[0092] At operation 625, the gNB-CU 106 may transfer, to the gNB-DU
108, information related to the downlink precoding. In some
embodiments, the gNB-CU 106 may transfer a precoding matrix packet
to the gNB-DU 108. The precoding matrix packet may include one or
more of: a number of virtual antenna ports; information related to
the second precoding matrix (such as coefficients, size of the
matrix and/or other); information related to the first precoding
matrix; and/or other information. In some embodiments, the gNB-CU
106 may encode the precoding matrix packet for transfer to the
gNB-DU 108 on the F1 interface, and the precoding matrix packet may
indicate the second precoding matrix and/or information related to
the precoding.
[0093] Embodiments are not limited to usage of the precoding matrix
packet in this operation and/or other operations, as other elements
may be used, in some embodiments. The precoding matrix packet may
be included in a 3GPP protocol, 5G protocol and/or NR protocol, in
some embodiments. Embodiments are not limited to usage of elements
from those protocols.
[0094] At operation 630, the gNB-CU 106 may determine a
prefiltering matrix for uplink prefiltering. In some embodiments,
the prefiltering matrix may be for conversion of first uplink
symbols received by the gNB-DU 108 from a UE 102 at the gNB-DU 108
to second uplink symbols for transfor to the gNB-CU 106 on the F1
interface, although the scope of embodiments is not limited in this
respect. In some embodiments, the gNB-DU 108 may determine the
prefiltering matrix. Accordingly, the gNB-CU 106 may not
necessarily perform operation 630, in some embodiments.
[0095] In some embodiments, the gNB-CU 106 may determine the
prefiltering matrix based at least partly on one or more signal
quality measurements. In a non-limiting example, the signal quality
measurements (and/or related information) may be received by the
gNB-CU 106 from the gNB-DU 108. The signal quality measurements may
be determined at the UE 102 and transmitted to the gNB-DU 108.
[0096] At operation 635, the gNB-CU 106 may transfer, to the gNB-DU
108, information related to the uplink prefiltering. In some
embodiments, the gNB-CU 106 may transfer a prefiltering matrix
packet to the gNB-DU 108. The prefiltering matrix packet may
include one or more of: a number of virtual antenna ports;
information related to the prefiltering matrix (such as
coefficients, size of the matrix and/or other); and/or other
information. Embodiments are not limited to usage of the
prefiltering matrix packet in this operation and/or other
operations, as other elements may be used, in some embodiments. The
prefiltering matrix packet may be included in a 3GPP protocol, 5G
protocol and/or NR protocol, in some embodiments. Embodiments are
not limited to usage of elements from those protocols.
[0097] At operation 640, the gNB-CU 106 may precode downlink
symbols by the first precoding matrix. At operation 645, the gNB-CU
106 may transfer the precoded downlink symbols to the gNB-DU 108.
At operation 650, the gNB-CU 106 may transfer one or more elements
to the gNB-DU 108.
[0098] In some embodiments, the gNB-CU 106 may precode, first
symbols from the data streams by the first precoding matrix to
generate second symbols for transfer on the H interface to the
gNB-DU 108. The gNB-DU 108 may precode the second symbols by the
second precoding matrix to generate third symbols for transmission
on the antennas. In some embodiments, the gNB-CU 106 may determine
the number of virtual ports as a number that is less than the
number of antennas coupled to the gNB-DU 108 to cause a size of the
second symbols to be less than a size of the third symbols.
[0099] In some embodiments, the gNB-DU 108 may determine the second
precoding matrix to convert the second data symbols into third data
symbols of size based on a number of antennas coupled to the gNB-DU
108. A number of rows of the second precoding matrix may be equal
to the number of antennas coupled to the gNB-DU 106, and a number
of columns of the second precoding matrix may be equal to the
number of virtual antenna ports.
[0100] In some embodiments, the first symbols may include a first
vector of length equal to the number of data streams at the gNB-CU
106. The second symbols may include a second vector of length equal
to the number of virtual ports. The second vector may be based on a
product of the first precoding matrix and the first vector. The
third symbols may include a third vector of length equal to the
number of antennas coupled. The third vector may be based on a
product of the second precoding matrix and the second vector.
[0101] In some embodiments, the first vector, the second vector,
and the third vector include symbols for transmission on a resource
element (RE) of a plurality of REs during a symbol period of a
plurality of symbol periods.
[0102] In some embodiments, if the first symbols are included in a
physical downlink shared channel (PDSCH), a physical downlink
control channel (PDCCH) or demodulation reference signals (DMRSs),
the gNB-CU 106 may precode, the first symbols by the first
precoding matrix for transfer on the F1 interface to the gNB-DU
108. In some embodiments, if the first symbols are included in
channel state information reference signals (CSI-RS), a primary
synchronization signal (PSS), a secondary synchronization signal or
a physical broadcast channel (PBCH), the gNB-CU 106 may: precode
the first symbols by the first precoding matrix for transfer on the
F1 interface to the gNB-DU 108; or transfer the first symbols
without precoding on the F1 interface to the gNB-DU 108. In some
embodiments, the gNB-CU 106 may generate the first symbols based on
a Fourier Transform (FT) operation on the one or more data
streams.
[0103] At operation 655, the gNB-CU 106 may receive, from the
gNB-DU 108, prefiltered uplink symbols from the gNB-DU 108. The
gNB-CU 106 may decode one or more uplink packets based on uplink
symbols (including but not limited to prefiltered uplink symbols)
received from the gNB-DU 108.
[0104] At operation 660, the gNB-CU 106 may receive one or more
elements from the gNB-DU 108. The elements may or may not be
prefiltered. The elements may be related to one or more of: a
sounding reference signal (SRS), random access channel (RACH)
and/or other.
[0105] In some embodiments, an apparatus of a gNB 105 and/or gNB-CU
106 may comprise memory. The memory may be configurable to store
the first and second precoding matrixes. The memory may store one
or more other elements and the apparatus may use them for
performance of one or more operations. The apparatus may include
processing circuitry, which may perform one or more operations
(including but not limited to operation(s) of the method 600 and/or
other methods described herein). The processing circuitry may
include a baseband processor. The baseband circuitry and/or the
processing circuitry may perform one or more operations described
herein, including but not limited to determination of the first and
second precoding matrixes. The apparatus may include an interface
to transfer the precoding matrix packet. The interface may transfer
and/or receive other blocks, messages and/or other elements.
[0106] In some embodiments, the antennas may be coupled to one or
more of: the gNB-DU 108, an apparatus of the gNB-DU 108, the gNB
105, and an apparatus of the gNB 105. In some embodiments, one or
more of the following may comprise the antennas: the gNB-DU 108, an
apparatus of the gNB-DU 108, the gNB 105, and an apparatus of the
gNB 105.
[0107] At operation 705, the gNB-DU 108 may receive information
related to one or more signal quality measurements. At operation
707, the gNB-DU 108 may transfer, to the gNB-CU 106, information
related to the signal quality measurements.
[0108] In some embodiments, the gNB-DU 108 may receive the
information related to the signal quality measurements from the UE
102. In some embodiments, the gNB-DU 108 may transfer information
(the information received from the UE 102, a portion of the
information received from the UE 102, information based on the
information received from the UE 102 and/or other) to the gNB-CU
106.
[0109] At operation 710, the gNB-DU 108 may receive, from the
gNB-CU 106, information related to a second precoding matrix for a
downlink precoding. At operation 715, the gNB-DU 108 may receive,
from the gNB-CU 106, information related to a number of virtual
antenna ports.
[0110] At operation 720, the gNB-DU 108 may determine the second
precoding matrix for the downlink precoding. In some embodiments,
the gNB-DU 108 may generate, for transmission to the UE 102, a
plurality of precoded signals based on a plurality of candidate
precoding matrixes. The gNB-DU 108 may receive, from the UE 102,
one or more signal quality measurements based on the plurality of
precoded signals. The gNB-DU 108 may determine the second precoding
matrix based at least partly on the signal quality
measurements.
[0111] In some embodiments, the gNB-DU 108 may determine the second
precoding matrix. In some embodiments, the information related to
the second precoding matrix (received from the gNB-CU 106 at
operation 710) may indicate the second precoding matrix.
Accordingly, the gNB-DU 108 may not necessarily perform operation
720, in some embodiments.
[0112] At operation 725, the gNB-DU 108 may receive, from the
gNB-CU 106, information related to uplink prefiltering. In some
embodiments, the information may include one or more of: a number
of virtual antenna ports; information related to the prefiltering
matrix (such as coefficients, size of the matrix and/or other);
and/or other information. In some embodiments, the information may
be included in a prefiltering matrix packet, although the scope of
embodiments is not limited in this respect.
[0113] In some embodiments, the prefiltering matrix may be for
conversion of first symbols received from a UE 102 on a plurality
of antennas to second symbols for transfer to the gNB-CU 106 on the
F1 interface. In some embodiments, a size of the first symbols may
be based on a number of the antennas, and a size of the second
symbols may be based on the number of virtual antenna ports. In
some embodiments, a number of rows of the prefiltering matrix may
be equal to the number of virtual antenna ports, and a number of
columns of the prefiltering matrix may be equal to the number of
antennas.
[0114] At operation 730, the gNB-DU 108 may determine a
prefiltering matrix for the uplink prefiltering. In some
embodiments, the gNB-DU 108 may determine the prefiltering matrix.
For instance, the gNB-DU 108 may determine the prefiltering matrix
based at least partly on information (such as the number of virtual
antenna ports) received at operation 725. In some embodiments, the
gNB-CU 106 may determine the prefiltering matrix and may transfer
information that indicates the prefiltering matrix. Accordingly,
the gNB-DU 108 may not necessarily perform operation 730, in some
embodiments.
[0115] At operation 735, the gNB-DU 108 may receive downlink
symbols from the gNB-CU 106. At operation 740, the gNB-DU 108 may
precode the downlink symbols by the second precoding matrix. At
operation 745, the gNB-DU 108 may transmit the precoded downlink
symbols to a UE 102.
[0116] In some embodiments, the downlink symbols received from the
gNB-CU 106 may be prefiltered by the gNB-CU 106 (such as by a first
precoding matrix), although the scope of embodiments is not limited
in this respect. Accordingly, the symbols transmitted to the UE 102
at operation 745 may be precoded by the first and second precoding
matrixes, in some embodiments.
[0117] At operation 750, the gNB-DU 108 may receive uplink symbols
from the UE 102. At operation 755, the gNB-DU 108 may prefilter the
uplink symbols. At operation 760, the gNB-DU 108 may transfer the
prefiltered uplink symbols to the gNB-CU 106.
[0118] In some embodiments, the gNB-DU 108 may prefilter first
symbols from the antennas by the prefiltering matrix to generate
second symbols for transfer on the F1 interface to the gNB-CU 106.
The gNB-CU 106 may decode an uplink packet based on the second
symbols. In some embodiments, the first symbols may include a first
vector of length equal to the number of antennas, the second
symbols may include a second vector of length equal to the number
of virtual antenna ports, and the second vector may be based on a
product of the prefiltering matrix and the first vector.
[0119] In some embodiments, the gNB-DU 108 may, if the first
symbols are included in a physical uplink shared channel (PUSCH) or
a physical uplink control channel (PUCCH): prefilter the first
symbols by the prefiltering matrix for transfer on the F1 interface
to the gNB-CU 106. In some embodiments, the gNB-DU 108 may, if the
first symbols are included in a sounding reference signal (SRS) or
a random access channel (RACH): prefilter the first symbols by the
prefiltering matrix for transfer on the F1 interface to the gNB-CU
106; or transfer the first symbols without prefiltering on the F1
interface to the gNB-CU 106. In some embodiments, the gNB-DU 108
may generate the first symbols based on an inverse Fourier
Transform (FT) operation on signals from the antennas.
[0120] In some embodiments, an apparatus of a gNB 105 and/or gNB-DU
108 may comprise memory. The memory may be configurable to store
the prefiltering matrix. The memory may store one or more other
elements and the apparatus may use them for performance of one or
more operations. The apparatus may include processing circuitry,
which may perform one or more operations (including but not limited
to operation(s) of the method 700 and/or other methods described
herein). The processing circuitry may include a baseband processor.
The baseband circuitry and/or the processing circuitry may perform
one or more operations described herein, including but not limited
to determination of the prefiltering matrix. The apparatus may
include a transceiver to receive uplink data symbols from the UE
102. The transceiver may transmit and/or receive other blocks,
messages and/or other element.
[0121] At operation 805, the UE 102 may determine one or more
signal quality measurements. At operation 810, the UE 102 may
transmit information related to the signal quality measurements to
the gNB-DU 108. At operation 815, the UE 102 may receive, from the
gNB-DU 108, downlink symbols. At operation 820, the UE 102 may
transmit, to the gNB-DU 108, uplink symbols.
[0122] In some embodiments, an apparatus of a UE 102 may comprise
memory. The memory may be configurable to store the signal quality
measurements. The memory may store one or more other elements and
the apparatus may use them for performance of one or more
operations. The apparatus may include processing circuitry, which
may perform one or more operations (including but not limited to
operation(s) of the method 800 and/or other methods described
herein). The processing circuitry may include a baseband processor.
The baseband circuitry and/or the processing circuitry may perform
one or more operations described herein, including but not limited
to determination of the signal quality measurements. The apparatus
may include a transceiver to transmit the information related to
the signal quality measurements. The transceiver may transmit
and/or receive other blocks, messages and/or other element.
[0123] FIG. 9 illustrates example operations in accordance with
some embodiments. FIG. 10 illustrates example operations in
accordance with some embodiments. It should be noted that the
examples shown in FIGS. 9-10 may illustrate some or all of the
concepts and techniques described herein in some cases, but
embodiments are not limited by the examples. For instance,
embodiments are not limited by the name, number, type, size,
ordering, arrangement of elements (such as devices, operations,
messages and/or other elements) shown in FIGS. 9-10. Although some
of the elements shown in the examples of FIGS. 9-10 may be included
in a 3GPP LTE standard, 5G standard, NR standard and/or other
standard, embodiments are not limited to usage of such elements
that: are included in standards.
[0124] In some embodiments, a functional split between a central
unit (CU) and a distributed unit (DU) may be used. Referring to
FIG. 9, three possible options 7-1, 7-2, and 7-3 are shown as (910,
920, 930). For each of the options 910, 920, 930, a dotted line is
shown. The dotted lines 911, 921, 931 correspond to options 910,
920, 930, respectively. For each of options 910, 920, 930, the
blocks to the left of the corresponding dotted line may be
performed by the CU 106 and the blocks to the right of the
corresponding dotted line may be performed by the DU 108. For
instance, for option 7-1 (910), the IFFT/CP block 912, DA 913,
FFT/CP 914, MACH filter 915, AD 916, and analog beamforming 917 are
to the right of the line 911. Those functions may be performed by
the DU 108. Other blocks to the left of the line, such as precoding
922, resource mapping 923, prefiltering 924, resource demapping 925
and others to the left of those blocks may be performed by the CU
106 in option 7-1 (910). In another example, for option 7-2 (920),
the blocks 912-917 and 922-925 are to the right of the line 921 and
may be performed by the DU 108, while other blocks to the left of
line 921 may be performed by the CU 106.
[0125] In some embodiments, a flexible front-haul interface design
with a configurable function partition between CU 106 and DU 108
for split physical layer functionality may be used. In some
embodiments, traffic load in the interface, including data and the
coefficient, may be from the digital antenna port level to user
stream level. This may depend on the capability of the
transportation network, in some cases.
[0126] In some embodiments, a flexible front-haul design may
support unified front-haul interface for physical layer split
solution options 7-1 and 7-2. A non-limiting example is shown in
FIG. 10. In some embodiments, the CU 106 may perform one or more
operations included in 1005. In some embodiments, the DU 108 may
perform one or more operations included in 1010.
[0127] The interface format can be unified and configured by CU 106
with different setup, such as number of digital antenna port/data
stream, pre-coding and pre-filter coefficients generation and
update frequency according to front-haul capability and performance
target.
[0128] In some embodiments, a pre-filtering block may be used in
the uplink. For instance, the pre-filtering may be used after an
IFFT and/or FFT. In some embodiments, a pre-coding block may be
used in the downlink. For instance, the pre-coding may be performed
at the DU 108 before an FFT and/or IFFT. The DU 108 may perform
operations related to data size, digital antenna number, data
stream number and/or other in accordance with parameters and/or
techniques setup by the CU 106.
[0129] In some embodiments, for the downlink, a precoding block may
be separated into two precoding sub-blocks. One precoding operation
may be performed by the CU 106 and the other precoding operation
may be performed by the DU 108. The detail functionality of two
sub-blocks may be controlled by the CU 106, in some
embodiments.
[0130] In some cases, such an interface design may be flexible to
support tradeoffs between the front-haul interface capability and
wireless performance with a unified interface controlled by CU
106.
[0131] In some cases, one or more of the embodiments described
herein may enable one or more of: a unified interface design for
different physical layer solutions; flexibility to adjust the
front-haul traffic from the digital antenna port level to user
stream level according to the transportation capability without
changing the functionality of the DU 108; pre-coding and
pre-filtering functionality that may be controlled by the CU 106
and may not necessarily need input/intelligence/processing by the
DU 108.
[0132] In some embodiments, two physical layer split option 7-1 and
7-2 may be unified with the same functionality in DU 108 and CU
106. To make the flexible interface design, more detail on
different solutions for uplink and downlink is given below. For
downlink, the traditional precoding may be separated to two
functionalities, precoding 1 and precoding 2, which may be loaded
in different units in some embodiments. The detailed precoding
solution and coefficient may be generated and controlled by the CU
106. The precoding matrix can be generated according to different
information, such as the CSI feedback (W1 & W2) by UEs 102, SRS
based channel estimation from UL at CU 106 and/or other. Both the
precoding 1 and 2 can be wideband, partial band and/or sub-band.
The traffic in front-haul interface between two precoding blocks
may be various from user stream level to digital antenna port level
based on the precoding 2 final definition and the updating
frequency.
[0133] In some embodiments, for the uplink, one or more of the
following may be used: CP removal, FTT, resource mapping, and/or
other. Such operation(s) may be performed to decompose the data and
SRS signal. A pre-filtering may be added at the DU 108 to downsize
the data traffic in front-haul interface. The pre-filtering may be
designed as a spatial filter according to channel statement
information to downsize the receiving data from digital antenna
port level to user stream level. The coefficient and updating
frequency for pre-filtering will be controlled by CU 106.
[0134] In some embodiments, the digital antenna ports may be
divided into several groups, and then pre-filtering may be
performed within each group. The group number and the number of
digital antenna ports per group can be configurable, so the virtual
antenna port can be adjusted between the digital antenna ports and
UE stream. This may be a tradeoff between system performance and
link traffic.
[0135] In some embodiments, for uplink and downlink independently,
the configuration of number of virtual antenna port may be
indicated by the CU 106 and capability of maximum number of virtual
antenna port in DU 108 may be known to CU 106. Then the following
example can be used for DL precoding and UL pre-filtering.
[0136] In a non-limiting example, for the downlink, suppose the gNB
105 has N.sub.TP transmitting digital antenna ports and serves
N.sub.s data stream concurrently. Denote the transmit symbol of
stream i as x.sub.i. The final transmission signal over the digital
antenna ports with two step precoding in frequency domain may be as
follows--Y=P.sub.2P.sub.1X. The matrix P.sub.2 may be of dimension
N.sub.TP.times.N.sub.VP. The matrix P1 may be a matrix of dimension
N.sub.VP x Ns for two steps' precoding individually. The vector
X=[x.sub.1, x.sub.2, . . . , x.sub.Ns].sup.T may be original
transmit signals. The parameter N.sub.VP may be a number of virtual
antenna ports after first step of precoding. The matrices P.sub.1
and P.sub.2 together may perform the whole digital beamforming.
They may be generated from the feedback CSI, UL SRS based channel
information by various algorithm(s) (including but not limited to
zero-forcing, SVD and/or other) and/or other technique(s).
[0137] In some embodiments, the matrices P.sub.1 and P.sub.2 may be
different. For PBCH, PDCCH, PSS/SSS and CSI-RS, wideband precoding
or DFT based precoding may be used tor wide coverage according to
current discussion in 3GPP.
[0138] In some embodiments, for data channel and DMRS, the
parameter N.sub.VP may be configurable to adjust the partition
between P.sub.1 and P.sub.2. In an ideal front-haul transport
network, N.sub.VP may be closer to N.sub.TP. In some embodiments,
when N.sub.VP is equal to N.sub.TP, P.sub.2 may be an identity
matrix. This may result in a transparent transmission. All of the
precoding work may be done by the CU 106. When the front-haul
transport network is had and/or performs poorly, N.sub.VP may be at
least N.sub.s, which means that P.sub.1 may be an identity matrix,
and the precoding may be performed entirely at the DU 108. The
precoding coefficients may be transmitted from the CU 106. The
granularity and frequency may depend on the front-haul capability.
So the parameter N.sub.VP together with a method to determine
P.sub.1 and P.sub.2 may be configurable with the same functionality
and interface. This may be a compromise among system performance,
link traffic and implementation complexity, in some cases.
[0139] In some embodiments, for the uplink, after resource
de-mapping, the SRS symbol may be decomposed. In some embodiments,
the SRS is not pre-filtered. The received PRACH signal may be
processed separately, in some embodiments.
[0140] In some embodiments, for the data channel, the gNB 105 may
include and/or be coupled to N.sub.RP receiving digital antenna
ports and may serve N.sub.s data streams concurrently. Denote the
corresponding channel frequency response between stream i and the
antenna j element as h.sub.i,j. The received frequency signal may
be written as Y=HX+n. The matrix H=[h.sub.1, h.sub.2, . . . ,
h.sub.Ns] of size N.sub.RP by N.sub.s may be a channel response
matrix. The vector h.sub.i=[h.sub.i,1, h.sub.i,2. . . ,
h.sub.i,NRP].sup.T may be a channel response vector. The vectors
X=[x.sub.1, x.sub.2, . . . , X.sub.Ns].sup.T and n=[n.sub.1,
n.sub.2, . . . , n.sub.NRP].sup.T may denote uplink transmit
signals and noise, respectively. The pre-filtering matrix may be
denoted as P.sub.f and the pre-filtered data may be
Y.sub.prefiltered=P.sub.fY.
[0141] In some embodiments, the antennas may be divided into
N.sub.G groups, wherein N.sub.G can be flexibly configured (such as
1, 2, 4 and/or other value). The grouped antenna can be denoted as
below.
H = [ H sub 1 H sub 2 H sub N G ] ##EQU00001##
[0142] In the above, H.sub.sub i may include the channel
information between all streams and partial receiving antenna
ports. In addition, the digital antenna ports within each group may
have no intersection, in some embodiments, and may be selected
independently. Then the pre-filtering matrix can be expressed as
below.
P.sub.f[N.sub.G.sub.N.sub.S.sub..times.N.sub.RP]=diag([diag(1/sqrt(diag(-
H.sub.sub i.sup.HH.sub.sub i)))])diag(H.sup.H)
[0143] A dimension of data that is transferred in front-haul
interface may be reduced from N.sub.RP to N.sub.G*N.sub.s. For
instance, suppose N.sub.G=2, and then the pre-filtering matrix
P.sub.f can be denoted as below.
P f [ 2 N S .times. N RP ] = [ diag ( 1 / sqrt ( diag ( H sub 1 H H
sub 1 ) ) ) 0 0 diag ( 1 / sqrt ( diag ( H sub 2 H H sub 2 ) ) ) ]
[ H sub 1 H 0 N S .times. N RP / 2 0 N S .times. N RP / 2 H sub 2 H
] ##EQU00002##
[0144] The compressed data stream may be written as below.
Y.sub.prefiltered[2N.sub.3.sub..times.1]=P.sub.f[2N.sub.3.sub..times.N.s-
ub.RP.sub.].times.Y
[0145] For this case, the dimension of data fed back may be reduced
from N.sub.RP to 2N.sub.s. Processing may be based on the
prefiltered received data of size 2N.sub.s. In some embodiments,
packets for different content and fields in packet header may be
used. Non-limiting examples are given in the table below.
TABLE-US-00001 Direction Packet type Packet Content From DU UL Data
packet Pre-fitlered PUSCH/PUCCH to CU (UL) SRS packet Pre-filtered
or non-pre-filtered SRS RACH packet Pre-filtered or
non-pre-filtered PRACH From CU DL Data packet Precoded PDSCH,
PDCCH, DMRS to DU (DL) Control packet Precoded or non-precoded
CSI-RS, SSS/PSS/PBCH Precoding DL precoding coefficient for P2
matrix packet Pre-filtering UL pre-filtering coefficient for
pre-filter matrix packet
[0146] In some embodiments, field(s) for packet sub type may be
used in the packet header for different content. In some
embodiments, for a downlink data packet, a field may indicate NVP .
In some embodiments, for downlink precoding, one or more fields may
indicate information related to one or more of: N.sub.VP, and
N.sub.TP, P.sub.2 matrix size and/or other.
[0147] In some embodiments, for the uplink, N.sub.VP may be
N.sub.G*N.sub.s. This may be a dimension after pre-filtering. So
for an uplink data packet, a field may indicate N.sub.VP. For a
prefiltering matrix packet, one or more fields may indicate
information related to one or more of; N.sub.VP, N.sub.RP, a
prefiltering matrix size and/or other.
[0148] In some embodiments, uplink pre-filtering and/or downlink
precoding may be generated based on one or more of: DFT based
beams, a covariance matrix based scheme and/or other. Hence, for a
precoding configuration and/or pre-filtering configuration, one or
more of the following elements may be indicated: a
precoder/pre-filter generation scheme indicator; a granularity
indication, such as one precoder/pre-filter per RB or per Precoding
Resource block Group (PRG) or per RB Group (RBG) or per bandwidth
part (BWP) or per carrier; a periodicity of precoder/pre-filter
update; and/or other.
[0149] In some embodiments, a packet and/or header related to
precoding and/or prefiltering ma include one or more of the
following: a granularity index, such as a carrier index,
RB/PRG/RBG/BWP index and/or other; one or more coefficients of a
precoder for a corresponding resource, such as an angle of DFT
based beam or coefficient for covariance matrix based scheme;
and/or other.
[0150] In some embodiments, for a control packet, few ports will be
enabled, and simpler scheme can be used. In some embodiments, the
control packet may include a content indicator for SSS/PSS and
PBCH. In some embodiments, for CSI-RS, an independent packet may be
used. In some embodiments, the packet may be pre-generated. In some
embodiments, the packet may be transmitted to DU 108 once and
saved/transmitted by DU 108 on schedule. In some embodiments, the
packet may be generated and transmitted from CU 106 to DU 108.
[0151] In some embodiments, a radio access system may include a CU
106 and a DU 108. Some functionality between the CU 106 and the DU
108 may be split inter physical layer. The CU 106 may transmit
downlink signals to the DU 108 with multiple virtual antenna ports.
Partial precoding may be performed at the DU 108. The CU 106 may
receive uplink signals from the DU 106 with virtual antenna ports
after pre-filtering at the DU 108.
[0152] In some embodiments, a number of virtual antenna ports may
be configured by the CU 106. In some embodiments, the DU 108 may
perform a mapping of the virtual antenna ports to digital antenna
ports by precoding coefficient(s) transmitted from CU 106. In some
embodiments, an angle of a DFT based precoder or covariance matrix
of precoder may be indicated by CU 106. In some embodiments, a
resource granularity of precoding coefficient(s) can be indicated
by CU 106. In some embodiments, a precoding coefficient update
periodicity can be configured by CU 106. In some embodiments, the
DU may perform a mapping of the digital antenna ports to virtual
antenna ports by pre-filtering coefficient(s) transmitted from CU
106. In some embodiments, a resource granularity of pre-filtering
coefficient(s) may be indicated by CU 106. In some embodiments, a
pre-filtering coefficient update periodicity may be configured by
CU 106.
[0153] In some embodiments, an interface between CU 106 and DU 108
may be a unified packet based front-haul interface, covering lower
layer split option 7-1, 7-2 and other split between these two
options. In some embodiments, one or more fields of a packet may
indicate one or more of: a content type, such as DL data packet, UL
data packet, pre-filtering matrix packet, precoding matrix packet,
control packet for CSI-RS, SS block and/or other. In some
embodiments, one or more fields of the packet may indicate one or
more of: a virtual antenna port number, a digital antenna port
number and/or other.
[0154] In some embodiments, one or more fields of a packet may
indicate one or more of: a resource granularity, an update
periodicity of precoding coefficient matrix and/or other. In some
embodiments, one or more fields of a packet may indicate one or
more of: a resource granularity, an update periodicity of
pre-filtering coefficient matrix and/or other.
[0155] In Example 1, a generation node B (gNB) may be configured
with logical nodes including a gNB central unit (gNB-CU) and a gNB
distributed unit (gNB-DU). The gNB-CU may be configured to
communicate with the gNB-DU over an F1 interface. An apparatus of
the gNB may comprise memory. The apparatus may further comprise
processing circuitry. The processing circuitry may be configured to
determine, by the gNB-CU, a first precoding, matrix and a second
precoding matrix for a precoding of one or more data streams for
transmission on a plurality of antennas coupled to the gNB-DU. The
precoding may be in accordance with a split functionality between
the gNB-CU and the gNB-DU that includes: precoding by the gNB-CU
with the first precoding matrix, and precoding by the gNB-DU with
the second precoding matrix. The gNB-CU may be configured to
precode first symbols from the data streams by the first precoding
matrix to generate second symbols for transfer on the F1 interface
to the gNB-DU. The gNB-DU may be configured to precode the second
symbols by the second precoding matrix to generate third symbols
for transmission on the antennas. The memory may be configured to
store the first and second precoding matrixes.
[0156] In Example 2, the subject matter of Example 1, wherein the
processing circuitry may be further configured to, by the gNB-CU,
encode a precoding matrix packet that indicates the second
precoding matrix, the precoding matrix packet encoded for transfer
to the gNB-DU on the F1 interface.
[0157] In Example 3, the subject matter of one or any combination
of Examples 1-2, wherein: a number of rows of the first precoding
matrix may be equal to a configurable number of virtual ports, a
number of columns of the first precoding matrix may be equal to a
number of the data streams, a number of rows of the second
precoding matrix may be equal to a number of the antennas, and a
number of columns of the second precoding matrix may be equal to
the number of virtual ports.
[0158] In Example 4, the subject matter of one or any combination
of Examples 1-3, wherein the first symbols may include a first
vector of length equal to the number of data streams. The second
symbols may include a second vector of length equal to the number
of virtual ports. The second vector may be based on a product of
the first precoding matrix and the first vector. The third symbols
may include a third vector of length equal to the number of
antennas. The third vector may be based on a product of the second
precoding matrix and the second vector.
[0159] In Example 5, the subject matter of one or any combination
of Examples 1-4, wherein the first vector, the second vector, and
the third vector may include symbols for transmission on a resource
element (RE) of a plurality of REs during a symbol period of a
plurality of symbol periods.
[0160] In Example 6, the subject matter of one or any combination
of Examples 1-5, wherein the processing circuitry may be further
configured to, by the gNB-CU, determine the number of virtual ports
as a number that is less than the number of antennas to cause a
size of the second symbols to be less than a size of the third
symbols.
[0161] In Example 7, the subject matter of one or any combination
of Examples 1-6, wherein the processing circuitry may be further
configured to, by the gNB-CU, if the first symbols are included in
a physical downlink shared channel (PDSCH), a physical downlink
control channel (PDCCH) or demodulation reference signals (DMRSs):
precode the first symbols by the first precoding matrix for
transfer on the F1 interface to the gNB-DU.
[0162] In Example 8, the subject matter of one or any combination
of Examples 1-7, wherein the processing circuitry may be further
configured to, by the gNB-CU, if the first symbols are included in
channel state information reference signals (CSI-RS), a primary
synchronization signal (PSS), a secondary synchronization signal or
a physical broadcast channel (PBCH): precode the first symbols by
the first precoding matrix for transfer on the Ft interface to the
gNB-DU; or transfer the first symbols without precoding on the F1
interface to the gNB-DU.
[0163] In Example 9, the subject matter of one or any combination
of Examples 1-8, wherein the processing circuitry may be further
configured to, by the gNB-CU, generate the first symbols based on a
Fourier Transform (FT) operation on the one or more data
streams.
[0164] In Example 10, the subject matter of one or any combination
of Examples 1-9, wherein the processing circuitry may be further
configured to, by the gNB-DU, decode a signal quality measurement
from a User Equipment (UE). The processing circuitry may be further
configured to, by the gNB-CU, based at least partly on the signal
quality measurement: select the first precoding matrix from first
candidate precoding matrixes; or select the second precoding matrix
from second candidate precoding matrixes.
[0165] In Example 11, the subject matter of one or any combination
of Examples 1-10, wherein the apparatus may further include a
transceiver to transmit the third symbols.
[0166] In Example 12, the subject matter of one or any combination
of Examples 1-11, wherein the apparatus may further include the
antennas.
[0167] In Example 13, the subject matter of one or any combination
of Examples 1-12, wherein the processing circuitry may include a
baseband processor to determine the first and second precoding
matrixes.
[0168] In Example 14, a generation Node-B (gNB) may be configured
with logical nodes including a gNB central unit (gNB-CU) and a gNB
distributed unit (gNB-DU), the gNB-CU configured to communicate
with the gNB-DU over an F1 interface. A non-transitory
computer-readable storage medium may store instructions for
execution by one or more processors to perform operations for
communication by the gNB. The operations may configure the one or
more processors to, by the gNB-CU: precode, by a first precoding
matrix, first data symbols from one or more data streams to
generate second data symbols for transfer to the gNB-DU on the F1
interface. A size of the second data symbols may be based on a
configurable number of virtual antenna ports. The operations may
further configure the one or more processors to, by the gNB-CU,
encode a precoding matrix packet for transfer to the gNB-DU on the
F1 interface. The precoding matrix packet may indicate the number
of virtual antenna ports. The operations may further configure the
one or more processors to, by the gNB-DU, determine a second
precoding matrix to convert the second data symbols into third data
symbols of size based on a number of antennas coupled to the
gNB-DU. A number of rows of the second precoding matrix may be
equal to the number of antennas coupled to the gNB-DU. A number of
columns of the second precoding matrix may be equal to the number
of virtual antenna ports.
[0169] In Example 15, the subject matter of Example 14, wherein the
operations may further configure the one or more processors to, by
the gNB-DU: generate, for transmission to a User Equipment (UE), a
plurality of precoded signals based on a plurality of candidate
precoding matrixes; decode, from the UE, one or more signal quality
measurements based on the plurality of precoded signals; and
determine the second precoding matrix based on the signal quality
measurements.
[0170] In Example 16, a generation node B (gNB) may be configured
with logical nodes including a gNB central unit (gNB-CU) and a gNB
distributed unit (gNB-DU). The gNB-CU may be configured to
communicate with the gNB-DU over an F1 interface. An apparatus of
the gNB may comprise memory. The apparatus may further comprise
processing circuitry. The processing circuitry may be configured
to, by the gNB-DU: decode, from the gNB-CU, a prefiltering matrix
packet that indicates a number of virtual antenna ports. The
processing circuitry may be further configured to, by the gNB-DU:
determine a prefiltering matrix to convert first symbols received
from a User Equipment (UE) on a plurality of antennas to second
symbols for transfer to the gNB-CU on the F1 interface. A size of
the first symbols may be based on a number of the antennas, and a
size of the second symbols may be based on the number of virtual
antenna ports. A number of rows of the prefiltering matrix may be
equal to the number of virtual antenna ports, and a number of
columns of the prefiltering matrix may be equal to the number of
antennas. The memory may be configured to store the prefiltering
matrix.
[0171] In Example 17, the subject matter of Example 16, wherein the
processing circuitry may be further configured to, by the gNB-DU,
prefilter first symbols from the antennas by the prefiltering
matrix to generate second symbols for transfer on the Ft interface
to the gNB-CU. The processing circuitry may be further configured
to, by the gNB-CU, decode an uplink packet based on the second
symbols.
[0172] In Example 18, the subject matter of one or any combination
of Examples 16-17, wherein the first symbols may include a first
vector of length equal to the number of antennas. The second
symbols may include a second vector of length equal to the number
of virtual antenna ports. The second vector may be based on a
product of the prefiltering matrix and the first vector.
[0173] In Example 19, the subject matter of one or any combination
of Examples 16-18, wherein the processing circuitry may be further
configured to, by the gNB-CU, select the number of virtual antenna
ports as less than the number of antennas to cause a size of the
second symbols to be less than a size of the first symbols.
[0174] In Example 20, the subject matter of one or any combination
of Examples 16-19, wherein the processing circuitry may be further
configured to, by the gNB-DU, if the first symbols are included in
a physical uplink shared channel (PUTSCH) or a physical uplink
control channel (PUCCH): prefilter the first symbols by the
prefiltering matrix for transfer on the F1 interface to the
gNB-CU.
[0175] In Example 21, the subject matter of one or any combination
of Examples 16-20, wherein the processing circuitry may be further
configured to, by the gNB-DU, if the first symbols are included in
a sounding reference signal (SRS) or a random access channel
(RACH): prefilter the first symbols by the prefiltering matrix for
transfer on the F1 interface to the gNB-CU; or transfer the first
symbols without prefiltering on the F1 interface to the gNB-CU.
[0176] In Example 22, the subject matter of one or any combination
of Examples 16-21, wherein the processing circuitry may be further
configured to, by the gNB-DU, generate the first symbols based on
an inverse Fourier Transform (FT) operation on signals from the
antennas.
[0177] In Example 23, the subject matter of one or any combination
of Examples 16-22, wherein the processing circuitry may be further
configured to, by the gNB-DU, decode a signal quality measurement
from the UE. The processing circuitry may be further configured to,
by the gNB-CU, select the prefiltering matrix from candidate
prefiltering matrixes based at least partly on the signal quality
measurement.
[0178] In Example 24, a generation Node-B (gNB) may be configured
with logical nodes including a gNB central unit (gNB-CU) and a gNB
distributed unit (gNB-DU). The gNB-CU may be configured to
communicate with the gNB-DU over an F1 interface. An apparatus of
the gNB may comprise means for, by the gNB-CU: precoding, by a
first precoding matrix, first data symbols from one or more data
streams to generate second data symbols for transfer to the gNB-DU
on the F1 interface. A size of the second data symbols may be based
on a configurable number of virtual antenna ports. The apparatus
may further comprise means for, by the gNB-CU, encoding a precoding
matrix packet for transfer to the gNB-DU on the F1 interface,
wherein the precoding matrix packet indicates the number of virtual
antenna ports. The apparatus may further comprise means for, by the
gNB-DU, determining, a second precoding matrix to convert the
second data symbols into third data symbols of size based on a
number of antennas coupled to the gNB-DU. A number of rows of the
second precoding matrix may be equal to the number of antennas
coupled to the gNB-DU. A number of columns of the second precoding
matrix may be equal to the number of virtual antenna ports.
[0179] In Example 25, the subject matter of Example 24, wherein the
apparatus may further comprise means for, by the gNB-DU:
generating, for transmission to a User Equipment (LTE), a plurality
of precoded signals based on a plurality of candidate precoding
matrixes; decoding, from the UE, one or more signal quality
measurements based on the plurality of precoded signals; and
determining the second precoding matrix based on the signal quality
measurements.
[0180] The Abstract is provided to comply with 37 C.F.R. Section
1.72(b) requiring an abstract that will allow the reader to
ascertain the nature and gist of the technical disclosure. It is
submitted with the understanding that it will not be used to limit
or interpret the scope or meaning of the claims. The following
claims are hereby incorporated into the detailed description, with
each claim standing on its own as a separate embodiment.
* * * * *