WO2021243675A1

WO2021243675A1 - Timer-based operations for a user equipment that includes multiple antenna panels

Info

Publication number: WO2021243675A1
Application number: PCT/CN2020/094546
Authority: WO
Inventors: Fang Yuan; Wooseok Nam; Yan Zhou; Tao Luo
Original assignee: Qualcomm Incorporated
Priority date: 2020-06-05
Filing date: 2020-06-05
Publication date: 2021-12-09

Abstract

A method of wireless communication includes receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG). The method further includes, in response to receiving the first TAC, initiating operation of a timer of the UE. The method further includes, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The method further includes determining, based on the second TAC indicating the second TAG, whether to reset the timer.

Description

TIMER-BASED OPERATIONS FOR A USER EQUIPMENT THAT INCLUDES MULTIPLE ANTENNA PANELS

BACKGROUND Technical Field

Aspects of the present disclosure relate generally to wireless communications systems, and more particularly, to wireless communication systems that include user equipments (UEs) having multiple antenna panels.

Description of the Related Technology

Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, and the like. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Such networks, which are usually multiple access networks, support communications for multiple users by sharing the available network resources. One example of such a network is the Universal Terrestrial Radio Access Network (UTRAN) . The UTRAN is the radio access network (RAN) defined as a part of the Universal Mobile Telecommunications System (UMTS) , a third generation (3G) mobile phone technology supported by the 3rd Generation Partnership Project (3GPP) . Examples of multiple-access network formats include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.

A wireless communication network may include a number of base stations or node Bs that can support communication for a number of user equipments (UEs) . A UE may communicate with a base station via downlink and uplink. The downlink (or forward link) refers to the communication link from the base station to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the base station.

A base station may transmit data and control information on the downlink to a UE and/or may receive data and control information on the uplink from the UE. On the downlink, a transmission from the base station may encounter interference due to transmissions from neighbor base stations or from other wireless radio frequency (RF) transmitters. On the uplink, a transmission from the UE may encounter interference from uplink transmissions of other UEs communicating with the neighbor base stations or from other wireless RF transmitters. This interference may degrade performance on both the downlink and uplink.

As the demand for mobile broadband access continues to increase, the possibilities of interference and congested networks grows with more UEs accessing the long-range wireless communication networks and more short-range wireless systems being deployed in communities. Research and development continue to advance wireless technologies not only to meet the growing demand for mobile broadband access, but to advance and enhance the user experience with mobile communications.

SUMMARY

In some aspects of the disclosure, a method of wireless communication includes receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) . The method further includes, in response to receiving the first TAC, initiating operation of a timer of the UE. The method further includes, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The method further includes determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In some other aspects of the disclosure, an apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to receive, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The one or more processors are further configured to initiate operation of a timer of the UE in response to receiving the first TAC. The one or more processors are further configured to receive, during operation of the timer and by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The one or more processors are further configured to determine, based on the second TAC indicating the second TAG, whether to reset the timer.

In some other aspects of the disclosure, an apparatus includes means for receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The apparatus further includes means for initiating operation of a timer of the UE in response to receiving the first TAC. The apparatus further includes means for receiving, during operation of the timer by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The apparatus further includes means for determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In some other aspects of the disclosure, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The operations further include, in response to receiving the first TAC, initiating operation of a timer of the UE. The operations further include, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The operations further include determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In some other aspects of the disclosure, a method of wireless communication includes, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiating operation of a first timer of the UE. The method further includes, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE. The method further includes, in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.

In some other aspects of the disclosure, the apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiate operation of a first timer of the UE. The one or more processors are further configured to, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiate operation of a second timer of the UE. The one or more processors are further configured to, in response to detecting expiration of one or both of the first timer or the second timer, perform, by the UE, one or more timer expiration operations.

In some other aspects of the disclosure, an apparatus includes means for initiating, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, operation of a first timer of the UE. The apparatus further includes means for initiating, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, operation of a second timer of the UE. The apparatus further includes means for performing, in response to detecting expiration of one or both of the first timer or the second timer, one or more timer expiration operations by the UE.

In some other aspects of the disclosure, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiating operation of a first timer of the UE. The operations further include, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE. The operations further include, in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.

In some other aspects of the disclosure, a method of wireless communication includes transmitting, by a first transmission and reception point (TRP) of a base station, a first TAC to a first antenna panel of the UE. The first TAC is associated with a first TAG. The method further includes transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE. The second TAC is associated with a second TAG.

In some other aspects of the disclosure, an apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to transmit, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The one or more processors are further configured to transmit, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, wherein the second TAC is associated with a second TAG.

In some other aspects of the disclosure, an apparatus includes means for transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The apparatus further includes means for transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG.

In some other aspects of the disclosure, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The operations further include transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the present disclosure may be realized by reference to the following drawings. In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

FIG. 1 is a block diagram illustrating an example of a wireless communications system according to some aspects of the disclosure.

FIG. 2 is a block diagram illustrating examples of a base station and a UE according to some aspects of the disclosure.

FIG. 3 is a block diagram illustrating a wireless communications system including base stations that use directional wireless beams in accordance with some aspects of the disclosure.

FIG. 4 is a block diagram illustrating another example of a wireless communications system in accordance with some aspects of the disclosure.

FIG. 5 is a block diagram illustrating another example of a wireless communications system in accordance with some aspects of the disclosure.

FIG. 6 is a timing diagram illustrating operations that may be performed by a UE in accordance with some aspects of the disclosure.

FIG. 7 is another timing diagram illustrating operations that may be performed by a UE in accordance with some aspects of the disclosure.

FIG. 8 is a block diagram illustrating another example of a wireless communications system in accordance with some aspects of the disclosure.

FIG. 9 is a flow chart illustrating an example of a method of operation of a UE in accordance with some aspects of the disclosure.

FIG. 10 is a flow chart illustrating another example of a method of operation of a UE in accordance with some aspects of the disclosure.

FIG. 11 is a flow chart illustrating an example of a method of operation of a base station in accordance with some aspects of the disclosure.

FIG. 12 is a block diagram illustrating an example of a UE in accordance with some aspects of the disclosure.

FIG. 13 is a block diagram illustrating an example of a base station in accordance with some aspects of the disclosure.

DETAILED DESCRIPTION

Some communication systems use timing advance (TA) parameters to determine transmission timing of uplink transmissions. For example, based on a particular propagation delay associated with uplink communications from a user equipment (UE) to a base station, the base station may assign a particular TA parameter to the UE to compensate for the propagation delay. In some wireless communication protocols, the base station transmits a timing advance command (TAC) to the UE to indicate the TA parameter. Further, multiple base stations may be included in a timing advance group (TAG) that is associated with a common TA parameter. In some examples, a TA parameter may expire after a threshold time interval (e.g., after expiration of a timer) if no additional TAC associated with the TAG is received during the threshold time interval.

In some aspects of the disclosure, a user equipment (UE) performs operations that enable use of multiple antenna panels of the UE in connection with TA parameters and timer operation. In some implementations, a serving cell is associated with multiple TAGs, such as if one transmission and reception point (TRP) of the serving cell belongs to a first TAG and if another TRP of the serving cell belongs to a second TAG. The first TRP may communicate with a first antenna panel of the UE, and a second TRP may communicate with a second antenna panel of the UE. In one example, the UE may associate a timer (e.g., a shared timer) with both the first TAG and the second TAG, and a TAC associated with either TAG may cause the UE to reset the timer. In another example, the UE may maintain separate timers for the TAGs, and a TAC associated with one TAG causes the UE to reset the timer associated with the TAG (but not to reset the timer associated with the other TAG) .

In some other aspects of the disclosure, upon expiration of a timer, the UE determines whether to perform certain timer expiration operations. In a first example, the UE performs the timer expiration operations for a serving cell based on expiration of each timer associated with the serving cell. In a second example, the UE performs the timer expiration operations for the serving cell based on expiration of at least one timer associated with the serving cell (e.g., without waiting for expiration of other times associated with the serving cell) . In a third example, the UE performs the timer expiration operations on a per-panel basis, such as by selectively performing the timer expiration operations for a first antenna panel associated with an expired timer without performing the timer expiration operations for a second antenna panel associated with an unexpired timer.

One or more aspects of the disclosure may improve performance of a wireless communication system. For example, certain operations described herein may be performed (at least in part) on a per-panel basis. In some cases, timing parameters may be discarded or other timing expiration operations may be performed on a panel-specific basis (alternatively or in addition to performing the operations on a TAG-specific basis) . In this case, a UE may adjust or compensate for differences in transmission timing between antenna panels. As a result, flexibility in a wireless communication system may be increased as compared to some wireless communication systems that perform certain operations on a TAG-only basis.

To further illustrate, the disclosure relates generally to wireless communication networks such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single-carrier FDMA (SC-FDMA) networks, LTE networks, GSM networks, 5th Generation (5G) or new radio (NR) networks, as well as other communications networks. As described herein, the terms “networks” and “systems” may be used interchangeably.

An OFDMA network may implement a radio technology such as evolved UTRA (E-UTRA) , IEEE 802.11, IEEE 802.16, IEEE 802.20, flash-OFDM and the like. UTRA, E-UTRA, and Global System for Mobile Communications (GSM) are part of universal mobile telecommunication system (UMTS) . In particular, long term evolution (LTE) is a release of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE are described in documents provided from an organization named “3rd Generation Partnership Project” (3GPP) , and cdma2000 is described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) . These various radio technologies and standards are known or are being developed. For example, the 3rd Generation Partnership Project (3GPP) is a collaboration between groups of telecommunications associations that aims to define a globally applicable third generation (3G) mobile phone specification. 3GPP long term evolution (LTE) is a 3GPP project which was aimed at improving the universal mobile telecommunications system (UMTS) mobile phone standard. The 3GPP may define specifications for the next generation of mobile networks, mobile systems, and mobile devices. The present disclosure is concerned with the evolution of wireless technologies from LTE, 4G, 5G, NR, and beyond with shared access to wireless spectrum between networks using a collection of new and different radio access technologies or radio air interfaces.

In particular, 5G networks contemplate diverse deployments, diverse spectrum, and diverse services and devices that may be implemented using an OFDM-based unified, air interface. In order to achieve these goals, further enhancements to LTE and LTE-A are considered in addition to development of the new radio technology for 5G NR networks. The 5G NR will be capable of scaling to provide coverage (1) to a massive Internet of things (IoTs) with an ultra-high density (e.g., ～1M nodes/km^2) , ultra-low complexity (e.g., ～10s of bits/sec) , ultra-low energy (e.g., ～10+ years of battery life) , and deep coverage with the capability to reach challenging locations; (2) including mission-critical control with strong security to safeguard sensitive personal, financial, or classified information, ultra-high reliability (e.g., ～99.9999%reliability) , ultra-low latency (e.g., ～ 1 ms) , and users with wide ranges of mobility or lack thereof; and (3) with enhanced mobile broadband including extreme high capacity (e.g., ～ 10 Tbps/km^2) , extreme data rates (e.g., multi-Gbps rate, 100+Mbps user experienced rates) , and deep awareness with advanced discovery and optimizations.

The 5G NR may be implemented to use optimized OFDM-based waveforms with scalable numerology and transmission time interval (TTI) ; having a common, flexible framework to efficiently multiplex services and features with a dynamic, low-latency time division duplex (TDD) /frequency division duplex (FDD) design; and with advanced wireless technologies, such as massive multiple input, multiple output (MIMO) , robust millimeter wave (mmWave) transmissions, advanced channel coding, and device-centric mobility. Scalability of the numerology in 5G NR, with scaling of subcarrier spacing, may efficiently address operating diverse services across diverse spectrum and diverse deployments. For example, in various outdoor and macro coverage deployments of less than 3GHz FDD/TDD implementations, subcarrier spacing may occur with 15 kHz, for example over 1, 5, 10, 20 MHz, and the like bandwidth. For other various outdoor and small cell coverage deployments of TDD greater than 3 GHz, subcarrier spacing may occur with 30 kHz over 80/100 MHz bandwidth. For other various indoor wideband implementations, using a TDD over the unlicensed portion of the 5 GHz band, the subcarrier spacing may occur with 60 kHz over a 160 MHz bandwidth. Finally, for various deployments transmitting with mmWave components at a TDD of 28 GHz, subcarrier spacing may occur with 120 kHz over a 500MHz bandwidth.

The scalable numerology of the 5G NR facilitates scalable TTI for diverse latency and quality of service (QoS) requirements. For example, shorter TTI may be used for low latency and high reliability, while longer TTI may be used for higher spectral efficiency. The efficient multiplexing of long and short TTIs to allow transmissions to start on symbol boundaries. 5G NR also contemplates a self-contained integrated subframe design with uplink/downlink scheduling information, data, and acknowledgement in the same subframe. The self-contained integrated subframe supports communications in unlicensed or contention-based shared spectrum, adaptive uplink/downlink that may be flexibly configured on a per-cell basis to dynamically switch between uplink and downlink to meet the current traffic needs.

Various other aspects and features of the disclosure are further described below. It should be apparent that the teachings herein may be embodied in a wide variety of forms and that any specific structure, function, or both being disclosed herein is merely representative and not limiting. Based on the teachings herein one of an ordinary level of skill in the art should appreciate that an aspect disclosed herein may be implemented independently of any other aspects and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, such an apparatus may be implemented or such a method may be practiced using other structure, functionality, or structure and functionality in addition to or other than one or more of the aspects set forth herein. For example, a method may be implemented as part of a system, device, apparatus, and/or as instructions stored on a computer readable medium for execution on a processor or computer. Furthermore, an aspect may comprise at least one element of a claim.

FIG. 1 is a block diagram illustrating 5G network 100 including various base stations and UEs configured according to aspects of the present disclosure. The 5G network 100 includes a number of base stations 105 and other network entities. A base station may be a station that communicates with the UEs and may also be referred to as an evolved node B (eNB) , a next generation eNB (gNB) , an access point, and the like. Each base station 105 may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to this particular geographic coverage area of a base station and/or a base station subsystem serving the coverage area, depending on the context in which the term is used.

A base station may provide communication coverage for a macro cell or a small cell, such as a pico cell or a femto cell, and/or other types of cell. A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions with the network provider. A small cell, such as a pico cell, would generally cover a relatively smaller geographic area and may allow unrestricted access by UEs with service subscriptions with the network provider. A small cell, such as a femto cell, would also generally cover a relatively small geographic area (e.g., a home) and, in addition to unrestricted access, may also provide restricted access by UEs having an association with the femto cell (e.g., UEs in a closed subscriber group (CSG) , UEs for users in the home, and the like) . A base station for a macro cell may be referred to as a macro base station. A base station for a small cell may be referred to as a small cell base station, a pico base station, a femto base station or a home base station. In the example shown in FIG. 1, the

base stations

105d and 105e are regular macro base stations, while base stations 105a-105c are macro base stations enabled with one of 3 dimension (3D) , full dimension (FD) , or massive MIMO. Base stations 105a-105c take advantage of their higher dimension MIMO capabilities to exploit 3D beamforming in both elevation and azimuth beamforming to increase coverage and capacity. Base station 105f is a small cell base station which may be a home node or portable access point. A base station may support one or multiple (e.g., two, three, four, and the like) cells.

The 5G network 100 may support synchronous or asynchronous operation. For synchronous operation, the base stations may have similar frame timing, and transmissions from different base stations may be approximately aligned in time. For asynchronous operation, the base stations may have different frame timing, and transmissions from different base stations may not be aligned in time.

The UEs 115 are dispersed throughout the wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as a terminal, a mobile station, a subscriber unit, a station, or the like. A UE may be a cellular phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, or the like. In one aspect, a UE may be a device that includes a Universal Integrated Circuit Card (UICC) . In another aspect, a UE may be a device that does not include a UICC. In some aspects, UEs that do not include UICCs may also be referred to as internet of everything (IoE) or internet of things (IoT) devices. UEs 115a-115d are examples of mobile smart phone-type devices accessing 5G network 100 A UE may also be a machine specifically configured for connected communication, including machine type communication (MTC) , enhanced MTC (eMTC) , narrowband IoT (NB-IoT) and the like. UEs 115e-115k are examples of various machines configured for communication that access 5G network 100. A UE may be able to communicate with any type of the base stations, whether macro base station, small cell, or the like. In FIG. 1, a lightning bolt (e.g., communication links) indicates wireless transmissions between a UE and a serving base station, which is a base station designated to serve the UE on the downlink and/or uplink, or desired transmission between base stations, and backhaul transmissions between base stations.

In operation at 5G network 100, base stations 105a-105c serve

UEs

115a and 115b using 3D beamforming and coordinated spatial techniques, such as coordinated multipoint (CoMP) or multi-connectivity. Macro base station 105d performs backhaul communications with base stations 105a-105c, as well as small cell, base station 105f. Macro base station 105d also transmits multicast services which are subscribed to and received by

UEs

115c and 115d. Such multicast services may include mobile television or stream video, or may include other services for providing community information, such as weather emergencies or alerts, such as Amber alerts or gray alerts.

5G network 100 also support mission critical communications with ultra-reliable and redundant links for mission critical devices, such UE 115e, which is a drone. Redundant communication links with UE 115e include from

macro base stations

105d and 105e, as well as small cell base station 105f. Other machine type devices, such as UE 115f (thermometer) , UE 115g (smart meter) , and UE 115h (wearable device) may communicate through 5G network 100 either directly with base stations, such as small cell base station 105f, and macro base station 105e, or in multi-hop configurations by communicating with another user device which relays its information to the network, such as UE 115f communicating temperature measurement information to the smart meter, UE 115g, which is then reported to the network through small cell base station 105f. 5G network 100 may also provide additional network efficiency through dynamic, low-latency TDD/FDD communications, such as in a vehicle-to-vehicle (V2V) mesh network between UEs 115i-115k communicating with macro base station 105e.

FIG. 2 shows a block diagram of a design of a base station 105 and a UE 115, which may be one of the base station and one of the UEs in FIG. 1. At the base station 105, a transmit processor 220 may receive data from a data source 212 and control information from a controller/processor 240. The control information may be for the PBCH, PCFICH, PHICH, PDCCH, EPDCCH, MPDCCH etc. The data may be for the PDSCH, etc. The transmit processor 220 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols, e.g., for the PSS, SSS, and cell-specific reference signal. A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc. ) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from modulators 232a through 232t may be transmitted via the antennas 234a through 234t, respectively.

At the UE 115, the antennas 252a through 252r may receive the downlink signals from the base station 105 and may provide received signals to the demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc. ) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all the demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 115 to a data sink 260, and provide decoded control information to a controller/processor 280.

On the uplink, at the UE 115, a transmit processor 264 may receive and process data (e.g., for the PUSCH) from a data source 262 and control information (e.g., for the PUCCH) from the controller/processor 280. The transmit processor 264 may also generate reference symbols for a reference signal. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by the modulators 254a through 254r (e.g., for SC-FDM, etc. ) , and transmitted to the base station 105. At the base station 105, the uplink signals from the UE 115 may be received by the antennas 234, processed by the demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 115. The processor 238 may provide the decoded data to a data sink 239 and the decoded control information to the controller/processor 240.

The controllers/

processors

240 and 280 may direct the operation at the base station 105 and the UE 115, respectively. The controller/processor 240 and/or other processors and modules at the base station 105 may perform or direct the execution of various processes for the techniques described herein. The controllers/processor 280 and/or other processors and modules at the UE 115 may also perform or direct the execution of the functional blocks illustrated in FIGS. 9 and 10 and/or other processes for the techniques described herein. The

memories

242 and 282 may store data and program codes for the base station 105 and the UE 115, respectively. A scheduler 244 may schedule UEs for data transmission on the downlink and/or uplink.

Wireless communications systems operated by different network operating entities (e.g., network operators) may share spectrum. In some instances, a network operating entity may be configured to use an entirety of a designated shared spectrum for at least a period of time before another network operating entity uses the entirety of the designated shared spectrum for a different period of time. Thus, in order to allow network operating entities use of the full designated shared spectrum, and in order to mitigate interfering communications between the different network operating entities, certain resources (e.g., time) may be partitioned and allocated to the different network operating entities for certain types of communication.

For example, a network operating entity may be allocated certain time resources reserved for exclusive communication by the network operating entity using the entirety of the shared spectrum. The network operating entity may also be allocated other time resources where the entity is given priority over other network operating entities to communicate using the shared spectrum. These time resources, prioritized for use by the network operating entity, may be utilized by other network operating entities on an opportunistic basis if the prioritized network operating entity does not utilize the resources. Additional time resources may be allocated for any network operator to use on an opportunistic basis.

Access to the shared spectrum and the arbitration of time resources among different network operating entities may be centrally controlled by a separate entity, autonomously determined by a predefined arbitration scheme, or dynamically determined based on interactions between wireless nodes of the network operators.

In some cases, UE 115 and base station 105 of the 5g network 100 (in FIG 1) may operate in a shared radio frequency spectrum band, which may include licensed or unlicensed (e.g., contention-based) frequency spectrum. In an unlicensed frequency portion of the shared radio frequency spectrum band, UEs 115 or base stations 105 may traditionally perform a medium-sensing procedure to contend for access to the frequency spectrum. For example, UE 115 or base station 105 may perform a listen before talk (LBT) procedure such as a clear channel assessment (CCA) prior to communicating in order to determine whether the shared channel is available. A CCA may include an energy detection procedure to determine whether there are any other active transmissions. For example, a device may infer that a change in a received signal strength indicator (RSSI) of a power meter indicates that a channel is occupied. Specifically, signal power that is concentrated in a certain bandwidth and exceeds a predetermined noise floor may indicate another wireless transmitter. A CCA also may include detection of specific sequences that indicate use of the channel. For example, another device may transmit a specific preamble prior to transmitting a data sequence. In some cases, an LBT procedure may include a wireless node adjusting its own backoff window based on the amount of energy detected on a channel and/or the acknowledge/negative-acknowledge (ACK/NACK) feedback for its own transmitted packets as a proxy for collisions.

In general, four categories of LBT procedure have been suggested for sensing a shared channel for signals that may indicate the channel is already occupied. In a first category (CAT 1 LBT) , no LBT or CCA is applied to detect occupancy of the shared channel. A second category (CAT 2 LBT) , which may also be referred to as an abbreviated LBT, a single-shot LBT, or a 25-μs LBT, provides for the node to perform a CCA to detect energy above a predetermined threshold or detect a message or preamble occupying the shared channel. The CAT 2 LBT performs the CCA without using a random back-off operation, which results in its abbreviated length, relative to the next categories.

A third category (CAT 3 LBT) performs CCA to detect energy or messages on a shared channel, but also uses a random back-off and fixed contention window. Therefore, when the node initiates the CAT 3 LBT, it performs a first CCA to detect occupancy of the shared channel. If the shared channel is idle for the duration of the first CCA, the node may proceed to transmit. However, if the first CCA detects a signal occupying the shared channel, the node selects a random back-off based on the fixed contention window size and performs an extended CCA. If the shared channel is detected to be idle during the extended CCA and the random number has been decremented to 0, then the node may begin transmission on the shared channel. Otherwise, the node decrements the random number and performs another extended CCA. The node would continue performing extended CCA until the random number reaches 0. If the random number reaches 0 without any of the extended CCAs detecting channel occupancy, the node may then transmit on the shared channel. If at any of the extended CCA, the node detects channel occupancy, the node may re-select a new random back-off based on the fixed contention window size to begin the countdown again.

A fourth category (CAT 4 LBT) , which may also be referred to as a full LBT procedure, performs the CCA with energy or message detection using a random back-off and variable contention window size. The sequence of CCA detection proceeds similarly to the process of the CAT 3 LBT, except that the contention window size is variable for the CAT 4 LBT procedure.

Use of a medium-sensing procedure to contend for access to an unlicensed shared spectrum may result in communication inefficiencies. This may be particularly evident when multiple network operating entities (e.g., network operators) are attempting to access a shared resource. In the 5G network 100, base stations 105 and UEs 115 may be operated by the same or different network operating entities. In some examples, an individual base station 105 or UE 115 may be operated by more than one network operating entity. In other examples, each base station 105 and UE 115 may be operated by a single network operating entity. Requiring each base station 105 and UE 115 of different network operating entities to contend for shared resources may result in increased signaling overhead and communication latency.

FIG. 3 illustrates an example of a timing diagram 300 for coordinated resource partitioning. The timing diagram 300 includes a superframe 305, which may represent a fixed duration of time (e.g., 20 ms) . The superframe 305 may be repeated for a given communication session and may be used by a wireless system such as 5G network 100 described with reference to FIG. 1. The superframe 305 may be divided into intervals such as an acquisition interval (A-INT) 310 and an arbitration interval 315. As described in more detail below, the A-INT 310 and arbitration interval 315 may be subdivided into sub-intervals, designated for certain resource types, and allocated to different network operating entities to facilitate coordinated communications between the different network operating entities. For example, the arbitration interval 315 may be divided into a plurality of sub-intervals 320. Also, the superframe 305 may be further divided into a plurality of subframes 325 with a fixed duration (e.g., 1 ms) . While timing diagram 300 illustrates three different network operating entities (e.g., Operator A, Operator B, Operator C) , the number of network operating entities using the superframe 305 for coordinated communications may be greater than or fewer than the number illustrated in timing diagram 300.

The A-INT 310 may be a dedicated interval of the superframe 305 that is reserved for exclusive communications by the network operating entities. In some examples, each network operating entity may be allocated certain resources within the A-INT 310 for exclusive communications. For example, resources 330-a may be reserved for exclusive communications by Operator A, such as through base station 105a, resources 330-b may be reserved for exclusive communications by Operator B, such as through base station 105b, and resources 330-c may be reserved for exclusive communications by Operator C, such as through base station 105c. Since the resources 330-a are reserved for exclusive communications by Operator A, neither Operator B nor Operator C can communicate during resources 330-a, even if Operator A chooses not to communicate during those resources. That is, access to exclusive resources is limited to the designated network operator. Similar restrictions apply to resources 330-b for Operator B and resources 330-c for Operator C. The wireless nodes of Operator A (e.g, UEs 115 or base stations 105) may communicate any information desired during their exclusive resources 330-a, such as control information or data.

When communicating over an exclusive resource, a network operating entity does not need to perform any medium sensing procedures (e.g., listen-before-talk (LBT) or clear channel assessment (CCA) ) because the network operating entity knows that the resources are reserved. Because only the designated network operating entity may communicate over exclusive resources, there may be a reduced likelihood of interfering communications as compared to relying on medium sensing techniques alone (e.g., no hidden node problem) . In some examples, the A-INT 310 is used to transmit control information, such as synchronization signals (e.g., SYNC signals) , system information (e.g., system information blocks (SIBs) ) , paging information (e.g., physical broadcast channel (PBCH) messages) , or random access information (e.g., random access channel (RACH) signals) . In some examples, all of the wireless nodes associated with a network operating entity may transmit at the same time during their exclusive resources.

In some examples, resources may be classified as prioritized for certain network operating entities. Resources that are assigned with priority for a certain network operating entity may be referred to as a guaranteed interval (G-INT) for that network operating entity. The interval of resources used by the network operating entity during the G-INT may be referred to as a prioritized sub-interval. For example, resources 335-a may be prioritized for use by Operator A and may therefore be referred to as a G-INT for Operator A (e.g., G-INT-OpA) . Similarly, resources 335-b may be prioritized for Operator B, (e.g., G-INT-OpB) , resources 335-c (e.g., G-INT-OpC) may be prioritized for Operator C, resources 335-d may be prioritized for Operator A, resources 335-e may be prioritized for Operator B, and resources 335-f may be prioritized for Operator C.

The various G-INT resources illustrated in FIG. 3 appear to be staggered to illustrate their association with their respective network operating entities, but these resources may all be on the same frequency bandwidth. Thus, if viewed along a time-frequency grid, the G-INT resources may appear as a contiguous line within the superframe 305. This partitioning of data may be an example of time division multiplexing (TDM) . Also, when resources appear in the same sub-interval (e.g., resources 340-a and resources 335-b) , these resources represent the same time resources with respect to the superframe 305 (e.g., the resources occupy the same sub-interval 320) , but the resources are separately designated to illustrate that the same time resources can be classified differently for different operators.

When resources are assigned with priority for a certain network operating entity (e.g., a G-INT) , that network operating entity may communicate using those resources without having to wait or perform any medium sensing procedures (e.g., LBT or CCA) . For example, the wireless nodes of Operator A are free to communicate any data or control information during resources 335-a without interference from the wireless nodes of Operator B or Operator C.

A network operating entity may additionally signal to another operator that it intends to use a particular G-INT. For example, referring to resources 335-a, Operator A may signal to Operator B and Operator C that it intends to use resources 335-a. Such signaling may be referred to as an activity indication. Moreover, since Operator A has priority over resources 335-a, Operator A may be considered as a higher priority operator than both Operator B and Operator C. However, as discussed above, Operator A does not have to send signaling to the other network operating entities to ensure interference-free transmission during resources 335-a because the resources 335-a are assigned with priority to Operator A.

Similarly, a network operating entity may signal to another network operating entity that it intends not to use a particular G-INT. This signaling may also be referred to as an activity indication. For example, referring to resources 335-b, Operator B may signal to Operator A and Operator C that it intends not to use the resources 335-b for communication, even though the resources are assigned with priority to Operator B. With reference to resources 335-b, Operator B may be considered a higher priority network operating entity than Operator A and Operator C. In such cases, Operators A and C may attempt to use resources of sub-interval 320 on an opportunistic basis. Thus, from the perspective of Operator A, the sub-interval 320 that contains resources 335-b may be considered an opportunistic interval (O-INT) for Operator A (e.g., O-INT-OpA) . For illustrative purposes, resources 340-a may represent the O-INT for Operator A. Also, from the perspective of Operator C, the same sub-interval 320 may represent an O-INT for Operator C with corresponding resources 340-b. Resources 340-a, 335-b, and 340-b all represent the same time resources (e.g., a particular sub-interval 320) , but are identified separately to signify that the same resources may be considered as a G-INT for some network operating entities and yet as an O-INT for others.

To utilize resources on an opportunistic basis, Operator A and Operator C may perform medium-sensing procedures to check for communications on a particular channel before transmitting data. For example, if Operator B decides not to use resources 335-b (e.g., G-INT-OpB) , then Operator A may use those same resources (e.g., represented by resources 340-a) by first checking the channel for interference (e.g., LBT) and then transmitting data if the channel was determined to be clear. Similarly, if Operator C wanted to access resources on an opportunistic basis during sub-interval 320 (e.g., use an O-INT represented by resources 340-b) in response to an indication that Operator B was not going to use its G-INT (e.g., resources 335-b) , Operator C may perform a medium sensing procedure and access the resources if available. In some cases, two operators (e.g., Operator A and Operator C) may attempt to access the same resources, in which case the operators may employ contention-based procedures to avoid interfering communications. The operators may also have sub-priorities assigned to them designed to determine which operator may gain access to resources if more than operator is attempting access simultaneously. For example, Operator A may have priority over Operator C during sub-interval 320 when Operator B is not using resources 335-b (e.g., G-INT-OpB) . It is noted that in another sub-interval (not shown) Operator C may have priority over Operator A when Operator B is not using its G-INT.

In some examples, a network operating entity may intend not to use a particular G-INT assigned to it, but may not send out an activity indication that conveys the intent not to use the resources. In such cases, for a particular sub-interval 320, lower priority operating entities may be configured to monitor the channel to determine whether a higher priority operating entity is using the resources. If a lower priority operating entity determines through LBT or similar method that a higher priority operating entity is not going to use its G-INT resources, then the lower priority operating entities may attempt to access the resources on an opportunistic basis as described above.

In some examples, access to a G-INT or O-INT may be preceded by a reservation signal (e.g., request-to-send (RTS) /clear-to-send (CTS) ) , and the contention window (CW) may be randomly chosen between one and the total number of operating entities.

In some examples, an operating entity may employ or be compatible with coordinated multipoint (CoMP) communications. For example an operating entity may employ CoMP and dynamic time division duplex (TDD) in a G-INT and opportunistic CoMP in an O-INT as needed.

In the example illustrated in FIG. 3, each sub-interval 320 includes a G-INT for one of Operator A, B, or C. However, in some cases, one or more sub-intervals 320 may include resources that are neither reserved for exclusive use nor reserved for prioritized use (e.g., unassigned resources) . Such unassigned resources may be considered an O-INT for any network operating entity, and may be accessed on an opportunistic basis as described above.

In some examples, each subframe 325 may contain 14 symbols (e.g., 250-μs for 60 kHz tone spacing) . These subframes 325 may be standalone, self-contained Interval-Cs (ITCs) or the subframes 325 may be a part of a long ITC. An ITC may be a self-contained transmission starting with a downlink transmission and ending with an uplink transmission. In some examples, an ITC may contain one or more subframes 325 operating contiguously upon medium occupation. In some cases, there may be a maximum of eight network operators in an A-INT 310 (e.g., with duration of 2 ms) assuming a 250-μs transmission opportunity.

Although three operators are illustrated in FIG. 3, it should be understood that fewer or more network operating entities may be configured to operate in a coordinated manner as described above. In some cases, the location of the G-INT, O-INT, or A-INT within the superframe 305 for each operator is determined autonomously based on the number of network operating entities active in a system. For example, if there is only one network operating entity, each sub-interval 320 may be occupied by a G-INT for that single network operating entity, or the sub-intervals 320 may alternate between G-INTs for that network operating entity and O-INTs to allow other network operating entities to enter. If there are two network operating entities, the sub-intervals 320 may alternate between G-INTs for the first network operating entity and G-INTs for the second network operating entity. If there are three network operating entities, the G-INT and O-INTs for each network operating entity may be designed as illustrated in FIG. 3. If there are four network operating entities, the first four sub-intervals 320 may include consecutive G-INTs for the four network operating entities and the remaining two sub-intervals 320 may contain O-INTs. Similarly, if there are five network operating entities, the first five sub-intervals 320 may contain consecutive G-INTs for the five network operating entities and the remaining sub-interval 320 may contain an O-INT. If there are six network operating entities, all six sub-intervals 320 may include consecutive G-INTs for each network operating entity. It should be understood that these examples are for illustrative purposes only and that other autonomously determined interval allocations may be used.

It should be understood that the coordination framework described with reference to FIG. 3 is for illustration purposes only. For example, the duration of superframe 305 may be more or less than 20 ms. Also, the number, duration, and location of sub-intervals 320 and subframes 325 may differ from the configuration illustrated. Also, the types of resource designations (e.g., exclusive, prioritized, unassigned) may differ or include more or less sub-designations.

FIG. 4 depicts another illustrative example of a communications system 400 in accordance with some aspects of the disclosure. The communications system 400 includes the UE 115, a first timing advance group (TAG) 402, and a second TAG 412. The first TAG 402 and the second TAG 412 may each may include one or more base stations. For example, the first TAG 402 may include one or more serving cells 404, and the second TAG 412 may include one or more serving cells 414. Alternatively or in addition, a TAG may include one or more transmission and reception points (TRPs) of a serving cell. For example, any serving cell of the serving

cells

404, 414 may include one or more TRPs, such as one or more TRPs 405 and one or more TRPs 415. In some examples, the

TRPs

405, 415 are included in a particular serving cell. For example, a particular serving cell may include the one or more TRPs 405 and the one or more TRPs 415. Any of the serving

cells

404, 414 may include or correspond to any of the base stations 105a-f of FIGS. 1-3.

The UE 115 includes multiple antenna panels, such as a first antenna panel 432 and a second antenna panel 434. In some examples, the first antenna panel 432 is associated with the first TAG 402, and the second antenna panel 434 is associated with the second TAG 412. For example, the UE 115 may use the first antenna panel 432 to receive one or more beams associated with the first TAG 402. The UE 115 may use the second antenna panel 434 to receive one or more beams associated with the second TAG 412. In one example, the first antenna panel 432 includes a first subset of the antennas 252a-r of FIG. 2, and the second antenna panel 434 includes a second subset of the antennas 252a-r of FIG. 2 that is different than the first subset.

During operation, the UE 115 may receive a first timing advance command (TAC) 406 associated with the first TAG 402. In some examples, the UE 115 receives the first TAC 406 from a first TRP of a serving cell using the first antenna panel 432. The first TAC 406 may include an indication 408 that the first TAC 406 is associated with the first TAG 402 and may further include a first timing advance (TA) parameter 409. In some examples, the first TA parameter 409 indicates a timing offset used by the UE 115 to communicate with the first TAG 402. For example, the UE 115 may adjust a start time of an uplink transmission to the first TAG 402 by advancing the start time by a particular time duration that is based on the first TA parameter 409 or by delaying the start time by a particular time duration that is based on the first TA parameter 409. The first TAC 406 may be indicated by a media-access channel control element (MAC-CE) or by MAC-CE signaling.

The UE 115 may receive a second TAC 416 associated with the second TAG 412. In some examples, the UE 115 receives the second TAC 416 from a second TRP of the serving cell using the second antenna panel 434. The second TAC 416 may include an indication 418 that the second TAC 416 is associated with the second TAG 412 and may further include a second TA parameter 419. In some examples, the second TA parameter 419 indicates a timing offset used by the UE 115 to communicate with the second TAG 412. For example, the UE 115 may adjust a start time of an uplink transmission to the second TAG 412 by advancing the start time by a particular time duration that is based on the second TA parameter 419 or by delaying the start time by a particular time duration that is based on the second TA parameter 419. The second TAC 416 may be indicated by a MAC-CE or by MAC-CE signaling. In some aspects, the first TAC 406 and the second TAC 416 may be indicated using a single signal or signaling. For example, a MAC-CE may indicate both the first TAC 406 and the second TAC 416.

In some examples, the

TA parameters

409, 419 are panel-specific. For example, the UE 115 may apply the first TA parameter 409 to signals transmitted using the first antenna panel 432 and may apply the second TA parameter 419 to signals transmitted using the second antenna panel 434. A signal transmitted using a panel may be associated with an explicit panel identity (ID) of the panel, such as if a first signal transmitted using the first antenna panel 432 is associated with a first panel ID of the first antenna panel 432, and if a second signal transmitted using the second antenna panel 434 is associated with a second panel ID of the second antenna panel 434. In some other aspects, a signal transmitted using a panel may be associated with an implicit panel ID of the panel. For example, a signal transmitted using the first antenna panel 432 may indicate a first parameter, such as one or more of a first control resource set (CORESET) pool index, a first transmission configuration indicator (TCI) , a first sounding reference signal (SRS) resource identity, or a first SRS resource set identity. The first parameter may be implicitly associated with the first antenna panel 432. As another example, a signal transmitted using the second antenna panel 434 may indicate a second parameter, such as one or more of a second CORESET pool index, a second TCI, a second SRS resource identity, or a second SRS resource set identity, and the second parameter may be implicitly associated with the second antenna panel 434.

In some cases, the first TA parameter 409 is different than the second TA parameter 419. For example, different propagation delays may be associated with the first TAG 402 relative to the second TAG 412 (or with the first antenna panel 432 relative to the second antenna panel 434) . To compensate for different propagation delays, the first TA parameter 409 may be different than the second TA parameter 419.

The UE 115 may initiate operation of a timer 440 in response to receiving the first TAC 406. As used herein, initiating operation of a timer my include setting or resetting the timer to a value and initiating counting from the value to another value. To further illustrate, the UE 115 may reset a value 442 of the timer 440 and may begin counting (e.g., by adjusting the value 442) to a threshold value 444 of the timer 440. In response to receiving one or more additional TACs associated with the first TAG 402 during operation of the timer 440, the UE 115 may reset the value 442 of the timer 440 and may resume counting to the threshold value 444. If the value 442 of the timer 440 reaches the threshold value 444, then the UE 115 may detect expiration of the timer 440. In this case, the UE 115 may perform one or more timer expiration operations, as described further below.

In the example of FIG. 4, in addition to resetting the timer 440 in response to receiving a TAC associated with the first TAG 402, the UE 115 may also set the timer 440 in response to receiving a TAC associated with the second TAG 412. To illustrate, the UE 115 may reset the timer 440 in response to receiving the second TAC 416. In the example of FIG. 4, the timer 440 may correspond to a “shared” timer that is reset in response to receiving a TAC from any of multiple TAGs. For example, the timer 440 may be shared between the first TAG 402 and the second TAG 412.

In some other implementations, different TAGs may be associated with different timers. To illustrate, FIG. 5 depicts another illustrative example of a communications system 500 in accordance with some aspects of the disclosure. In the example of FIG. 5, the UE 115 includes a first timer 540 associated with the first TAG 402 and further includes a second timer 550 associated with the second TAG 412.

In FIG. 5, the UE 115 may initiate operation of the first timer 540 in response to receiving the first TAC 406. For example, the UE 115 may reset a value 542 of the first timer 540 and may begin counting (e.g., by adjusting the value 542) to a threshold value 544 of the timer 440 (e.g., the threshold value 444 or another threshold value) . In response to receiving one or more additional TACs associated with the first TAG 402 during operation of the first timer 540, the UE 115 may reset the value 542 of the first timer 540 and may resume counting to the threshold value 544. If the value 542 of the first timer 540 reaches the threshold value 544, then the UE 115 may detect expiration of the first timer 540. In this case, the UE 115 may perform one or more timer expiration operations, as described further below.

Further, the UE 115 may operate the first timer 540 independently of TACs received from other TAGs, such as the second TAG 412. To illustrate, the UE 115 may receive the second TAC 416 and may refrain from resetting the value 542 of the first timer 540 in response to the second TAC 416. Accordingly, in some examples, the UE 115 may reset the first timer 540 based on the first TAC 406 indicating the first TAG 402 (e.g., based on the indication 408) and without resetting the first timer 540 based on the second TAC 416.

To further illustrate, in response to receiving the second TAC 416, the UE 115 may initiate operation of the second timer 550. For example, the UE 115 may reset a value 552 of the second timer 550 and may begin counting (e.g., by adjusting the value 552) to a threshold value 554 of the timer 440 (e.g., the threshold value 444, the threshold value 544, or another threshold value) . In response to receiving one or more additional TACs associated with the second TAG 412 during operation of the second timer 550, the UE 115 may reset the value 552 of the second timer 550 and may resume counting to the threshold value 554. If the value 552 of the second timer 550 reaches the threshold value 554, then the UE 115 may detect expiration of the second timer 550. In this case, the UE 115 may perform one or more timer expiration operations, as described further below. Depending on the particular implementation, the threshold value 554 may correspond to or may be different than the threshold value 544.

Further, the UE 115 may operate the second timer 550 independently of TACs received from other TAGs, such as the first TAG 402. To illustrate, the UE 115 may receive the first TAC 406 and may refrain from resetting the value 552 of the second timer 550 in response to the first TAC 406. Accordingly, in some examples, the UE 115 may reset the second timer 550 based on the second TAC 416 indicating the second TAG 412 (e.g., based on the indication 418) and without resetting the second timer 550 based on the first TAC 406.

To further illustrate, FIG. 6 depicts an example of a timing diagram illustrating operations 600 that may be performed by the UE 115 in accordance with some aspects of the disclosure. In some examples, the operations 600 correspond to the example of FIG. 4 (e.g., where a timer is “shared” among multiple TAGs) .

The operations 600 may include receiving a first TAC (e.g., the first TAC 406) , at 602, and may further include receiving a second TAC (e.g., the second TAC 416) , at 604. In one example, the first TAC is received from a first TRP of the base station 105, and the second TAC is received from a second TRP of the base station 105. In response to receiving the first TAC, the UE 115 may start or restart the timer 440. The UE 115 may perform a counting process (indicated by “P” ) using the timer 440 (e.g., by adjusting the value 442 until the value 442 corresponds to the threshold value 444) .

In the example of FIG. 6, the UE 115 receives the second TAC prior to expiration of the timer 440. In response to receiving the second TAC, the UE 115 may start or restart the timer 440. At 606, the UE 115 may detect expiration of the timer 440. Thus, in the example of FIG. 6, the UE 115 may start or restart the timer 440 based on receiving either the first TAC or the second TAC.

FIG. 7 depicts an example of a timing diagram illustrating operations 700 that may be performed by the UE 115 in accordance with some aspects of the disclosure. In some examples, the operations 700 correspond to the example of FIG. 5 (e.g., where a timer is associated with one TAG instead of multiple TAGs) .

The operations 700 may include receiving a first TAC (e.g., the first TAC 406) , at 702, and may further include receiving a second TAC (e.g., the second TAC 416) , at 704. In one example, the first TAC is received from a first TRP of the base station 105, and the second TAC is received from a second TRP of the base station 105. In response to receiving the first TAC, the UE 115 may start or restart the first timer 540. The UE 115 may perform a counting process (indicated by “P” ) using the first timer 540 (e.g., by adjusting the value 542 until the value 542 corresponds to the threshold value 544) . In response to receiving the second TAC, the UE 115 may start or restart the second timer 550. The UE 115 may perform a counting process (indicated by “P” ) using the second timer 550 (e.g., by adjusting the value 552 until the value 552 corresponds to the threshold value 554) .

The operations 700 may further include detecting expiration of the first timer 540, at 706, because the second TAC does not start or restart the first timer 540. The operations 700 may further include receiving an additional second TAC, at 708. The UE 115 may start or restart the second timer 550 in response to receiving the second TAC.

In some implementations, upon expiration of a timer, the UE 115 may perform one or more timer expiration operations. For example, the UE 115 may perform a timer expiration operation to clear “stale” information associated with an expired TA parameter. In some cases, the UE 115 may be in communication with a particular serving cell that is associated with multiple timers of the UE 115. To illustrate, a particular serving cell may include a first TRP that is included in the first TAG 402 (and that is associated with the first timer 540) and may further include a second TRP that is included in the second TAG 412 (and that is associated with the second timer 550) . In a first example, the UE 115 may perform the one or more timer expiration operations based on detecting expiration of all timers associated with the particular serving cell (e.g., by waiting until each timer associated with the particular serving cell is expired to perform the one or more timer expiration operations) . In a second example, the UE may perform the one or more timer expiration operations based on detecting expiration of any timer associated with the particular serving cell (e.g., by performing the one or more timer expiration operations upon expiration of at least one timer associated with the particular serving cell) . In a third example, the UE 115 may perform the one or more timer expiration operations on a panel-specific basis. Certain examples of timer expiration operations are described further with reference to FIG. 8.

FIG. 8 is a block diagram illustrating another example of a wireless communication system 800. The example of FIG. 8 may include or correspond to one or more aspects described with reference to the example of FIG. 5. For example, the UE 115 may include the first timer 540 and the second timer 550. In some examples, the first timer 540 is associated with a first TRP of the first TAG 402, the second timer 550 is associated with a second TRP of the second TAG 412, and the first TRP and the second TRP are included in a particular serving cell.

In some aspects of a first example, the UE 115 may perform the one or more timer expiration operations based on detecting expiration of all timers associated with the particular serving cell (e.g., by waiting until each timer associated with the particular serving cell is expired to perform the one or more timer expiration operations) . In this case, the UE 115 may detect expiration of the first timer 540 and the second timer 550, and the UE 115 may perform the one or more timer expiration operations based on detecting expiration of the first timer 540 and the second timer 550.

In some aspects of a second example, the UE may perform the one or more timer expiration operations based on detecting expiration of any timer associated with the particular serving cell (e.g., by performing the one or more timer expiration operations upon expiration of at least one timer associated with the particular serving cell) . In this case, the UE 115 detect expiration one or both of the first timer 540 and the second timer 550 and may perform the one or more timer expiration operations based on detecting expiration of one or both of the first timer 540 and the second timer 550.

In some aspects of the first example and the second example, the UE 115 may selectively perform one or more timer expiration operations based on whether the particular serving cell is included in a primary timing advance group (PTAG) of the UE 115 or in a secondary timing advance group (STAG) of the UE 115. To illustrate, in some examples, the first TAG 402 corresponds to the PTAG, and the second TAG 412 corresponds to the STAG (or vice versa) . The PTAG may include a primary serving cell that provides radio resource control (RRC) messages to the UE 115. As used herein, if the particular serving cell is associated with at least one timer of a PTAG of the UE 115, the particular serving cell may be referred to as being included in a PTAG of the UE 115. In some other cases, if the particular serving cell is not associated with at least one timer of a PTAG of the UE 115, the particular serving cell may be referred to as being included in an STAG of the UE 115. In some examples, the UE 115 performs the one or more timer expiration operations for multiple TAGs (e.g., both the PTAG and the STAG) if the particular serving cell is included in the PTAG and performs timer expiration operations for one TAG (e.g., the STAG but not the PTAG) if the particular serving cell is included in the PTAG.

To illustrate, in some aspects of the first example and the second example, if the particular serving cell is included in the PTAG, performing the one or more timer expiration operations may include flushing hybrid automatic repeat request (HARQ) buffers 802 associated with serving cells of the UE 115, such as the serving

cells

404 and 414. Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more physical uplink control channel (PUCCH) configurations 804 associated with serving cells of the UE 115, such as the serving

cells

404 and 414. Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more sounding reference signal (SRS) configurations 806 associated with the UE 115. Performing the one or more timer expiration operations may include clearing one or more downlink assignments 808, clearing one or more configured uplink grants 810, or both. Performing the one or more timer expiration operations may include clearing one or more physical uplink shared channel (PUSCH) configurations 812 for semi-persistent channel state information (CSI) reporting. Performing the one or more timer expiration operations may include determining that each running timer of the UE 115 is expired (e.g., by “forcing” each running timer of the UE 115 to an expired state) . Performing the one or more timer expiration operations may include maintaining a timing advance value for each TAG associated with the UE 115. In some examples, the timing advance value corresponds to an N_TA parameter (e.g., a timing difference between uplink signals and downlink signals) specified by a 5G NR wireless communication protocol.

Alternatively, in some aspects of the first example or the second example, if the particular serving cell is included in the STAG, performing the one or more timer expiration operations may include flushing HARQ buffers 802 associated with serving cells of the STAG (e.g., by flushing HARQ buffers 802 associated with the second TAG 412 without flushing HARQ buffers 802 associated with the first TAG 402) . Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more PUCCH configurations 804 associated with serving cells of the STAG (e.g., by releasing one or more PUCCH configurations 804 associated with the second TAG 412 without releasing one or more PUCCH configurations 804 associated with the first TAG 402) . Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more SRS configurations 806 associated with serving cells of the STAG (e.g., by releasing one or more SRS configurations 806 associated with the second TAG 412 without releasing one or more SRS configurations 806 associated with the first TAG 402) . Performing the one or more timer expiration operations may include clearing one or more downlink assignments 808 for serving cells of the STAG, clearing one or more configured uplink grants 810 for the serving cells of the STAG, or both (e.g., by clearing downlink assignments 808 and configured uplink grants 810 for the second TAG 412 but not for the first TAG 402) . Performing the one or more timer expiration operations may include clearing one or more PUSCH configurations 812 for semi-persistent CSI reporting associated with serving cells of the STAG (e.g., by clearing PUSCH configurations 812 for the second TAG 412 but not for the first TAG 402) . Performing the one or more timer expiration operations may include maintaining a timing advance value associated with the STAG. In some examples, the timing advance value corresponds to an N_TA parameter (e.g., a timing difference between uplink signals and downlink signals) specified by a 5G NR wireless communication protocol.

In some aspects of a third example, the UE 115 may perform the one or more timer expiration operations on a panel-specific basis. In an illustrative example, the first timer 540 is associated with a particular antenna panel of the UE 115, such as the first antenna panel 432. In this case, if the UE 115 detects expiration of the first timer 540 without detecting expiration of the second timer 550, the UE 115 may perform the one or more timer expiration operations for the particular antenna panel (e.g., the first antenna panel 432) based on detecting expiration of the first timer 540 without detecting expiration of the second timer 550. In some examples, the particular antenna panel is associated with a panel ID 814 (e.g., a panel index value) that indicates the particular antenna panel.

To illustrate, in some aspects of the third example, performing the one or more timer expiration operations may include flushing HARQ buffers 802 associated with the panel ID 814. Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more PUCCH configurations 804 associated with the panel ID 814. Performing the one or more timer expiration operations may include transmitting an RRC request to release one or more SRS configurations 806 associated with the panel ID 814. Performing the one or more timer expiration operations may include clearing one or more downlink assignments 808 associated with the panel ID 814, clearing one or more configured uplink grants 810 associated with the panel ID 814, or both. Performing the one or more timer expiration operations may include clearing one or more PUSCH configurations 812 for semi-persistent CSI reporting associated with the panel ID 814. Performing the one or more timer expiration operations may include maintaining a timing advance value associated with the panel ID 814 (e.g., by maintaining the first TA parameter 409 and by discarding the second TA parameter 419) .

In some examples, the panel ID 814 may be determined or indicated explicitly, such as by including the panel ID 814 in a message, such as an RRC message. For example, an RRC message provided by the UE 115 to the particular serving cell (or vice versa) using the first antenna panel 432 may designate the first antenna panel 432 as corresponding to the panel ID 814. In other examples, the panel ID 814 may be “inferred” using other signals or information, which may avoid transmission of one or more messages (e.g., RRC messages) in some cases. To illustrate, in some examples, the panel ID 814 is determined using one or more of a TAG ID, a control resource set (CORESET) pool index ID, or an SRS resource set ID.

One or more aspects described with reference to FIGS. 4-8 may improve performance of a wireless communication system. For example, certain operations described herein may be performed (at least in part) on a per-panel basis. In some cases, timing parameters may be discarded or other timing expiration operations may be performed on a panel-specific basis (alternatively or in addition to performing the operations on a TAG-specific basis) . In this case, the UE 115 may adjust or compensate for differences in transmission timing between antenna panels. As a result, flexibility in a wireless communication system may be increased as compared to some wireless communication systems that perform certain operations on a TAG-only basis.

FIG. 9 depicts an illustrative example of a method 900 of wireless communication of a UE in accordance with some aspects of the disclosure. In some examples, the method 900 is performed by the UE 115.

The method 900 includes receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, at 902. For example, the UE 115 may receive the first TAC 406 from a serving cell that is included in any of the serving

cells

404, 414 or from a TRP that is included in any of the

TRPs

405, 415.

The method 900 further includes, in response to receiving the first TAC, initiating operation of a timer of the UE, at 904. In one example, the UE 115 may start or restart the timer 440 in response to receiving the first TAC 406. In another example, the UE 115 may start or restart the first timer 540 in response to receiving the first TAC 406.

The method 900 further includes, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, at 906. For example, the UE 115 may receive the second TAC 416 during operation of the timer 440 (and prior to expiration of the timer 440) or during the operation of the first timer 540 (and prior to expiration of the first timer 540) . The UE 115 may receive the second TAC 416 from a serving cell that is included in any of the serving

cells

404, 414 or from a TRP that is included in any of the

TRPs

405, 415. In some examples, the UE 115 receives the first TAC 406 from a first TRP of the serving cell and receives the second TAC 416 from a second TRP of the serving cell.

The method 900 further includes determining, based on the second TAC indicating the second TAG, whether to reset the timer, at 908. In one example, the timer (e.g., the timer 440) is shared between the first TAG 402 and the second TAG 412, and the UE 115 resets the timer 440 based on the second TAC 416 indicating the second TAG 412 (e.g., as described with reference to one or more aspects of FIGS. 4 and 6) . In some other examples, the timer (e.g., the first timer 540) is associated with the first TAG 402, the second timer 550 is associated with the second TAG 412, and the UE resets the second timer 550 based on the second TAC 416 indicating the second TAG 412 and without resetting the timer based on the second TAC 416 (e.g., as described with reference to one or more aspects of FIGS. 5 and 7) .

FIG. 10 depicts an illustrative example of a method 1000 of wireless communication of a UE in accordance with some aspects of the disclosure. In some examples, the method 1000 is performed by the UE 115.

The method 1000 includes, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiating operation of a first timer of the UE, at 1002. For example, in response to receiving the first TAC 406, the UE 115 may initiate operation of the first timer 540 (e.g., by starting or restarting the first timer 540) .

The method 1000 further includes, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE, at 1004. For example, in response to receiving the second TAC 416, the UE 115 may initiate operation of the second timer 550 (e.g., by starting or restarting the second timer 550) .

The method 1000 further includes, in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations, at 1006. In an illustrative example, the UE 115 performs any of the timer expiration operations described with reference to FIG. 8. In a first example, the UE 115 may perform the one or more timer expiration operations based on detecting expiration of all timers associated with the particular serving cell (e.g., by waiting until both the

timers

540, 550 are expired to perform the one or more timer expiration operations) . In a second example, the UE 115 may perform the one or more timer expiration operations based on detecting expiration of any timer associated with the particular serving cell (e.g., by performing the one or more timer expiration operations upon expiration of any of the timers 540, 550) . In a third example, the UE 115 may perform the one or more timer expiration operations on a panel-specific basis (e.g., by performing the one or more timer expiration operations for the first antenna panel 432 but not the second antenna panel 434, or vice versa) .

FIG. 11 depicts an illustrative example of a method 1100 of wireless communication of a base station in accordance with some aspects of the disclosure. In some examples, the method 1000 is performed by the base station 105, which may correspond to a serving cell of any of the serving

cells

404, 414.

The method 1100 includes transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG, at 1102. For example, the base station 105 may include the first TRP, and the first TRP may be included in the one or more TRPs 405. The base station 105 may transmit the first TAC 406 to the UE 115 using the first TRP.

The method 1100 further includes transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG, at 1104. For example, the base station 105 may include the second TRP, and the second TRP may be included in the one or more TRPs 415. The base station 105 may transmit the second TAC 416 to the UE 115 using the second TRP.

FIG. 12 is a block diagram illustrating an example of a UE 115 according to some aspects of the disclosure. The UE 115 may include the controller/processor 280 and the memory 282. The controller/processor 280 may execute instructions 1202 stored in the memory 282 to initiate, perform, or control one or more operations described herein. The controller/processor 280 may execute the instructions 1202 to transmit and receive signals via wireless radios 1201a-r and the antennas 252a-r. The antenna 252a-r may be included in the

antenna panels

432, 434. The wireless radios 1201a-r may include hardware or other components corresponding to one or more features described with reference to FIG. 2, such as the modulator/demodulators 254a-r, the MIMO detector 256, the receive processor 258, the transmit processor 264, the TX MIMO processor 266, one or more other components, or a combination thereof. In some examples, the memory 282 stores panel-to-TAG mapping information 1203 that indicates a mapping of antenna panels to TAGs, such as a mapping of the first TAG 402 to the first antenna panel 432 and the second TAG 412 to the second antenna panel 434.

FIG. 13 is a block diagram illustrating an example of a base station 105 according to some aspects of the disclosure. The base station 105 may include the controller/processor 240 and the memory 242. The controller/processor 240 may execute instructions 1302 stored in the memory 242 to initiate, perform, or control one or more operations described herein. The controller/processor 240 may execute the instructions 1302 to transmit and receive signals via wireless radios 1301a-t and the antennas 234a-t. The wireless radios 1301a-t may include hardware or other components corresponding to one or more features described with reference to FIG. 2, such as the modulator/demodulators 232a-t, the MIMO detector 236, the receive processor 238, the transmit processor 220, the TX MIMO processor 230, one or more other components, or a combination thereof. In some examples, the memory 282 stores the panel-to-TAG mapping information 1203.

In a first aspect, a method of wireless communication includes receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The method further includes, in response to receiving the first TAC, initiating operation of a timer of the UE. The method further includes, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The method further includes determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In a second aspect alone or in combination with the first aspect, the timer is shared between the first TAG and the second TAG, and the method further includes resetting the timer based on the second TAC indicating the second TAG.

In a third aspect alone or in combination with one or more of the first through second aspects, the timer is associated with the first TAG, a second timer of the UE is associated with the second TAG, and the method further includes resetting the second timer based on the second TAC indicating the second TAG and without resetting the timer based on the second TAC.

In a fourth aspect alone or in combination with one or more of the first through third aspects, the first TAC is received from a first TRP of the serving cell, and the second TAC is received from a second TRP of the serving cell.

In a fifth aspect, an apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to receive, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The one or more processors are further configured to initiate operation of a timer of the UE in response to receiving the first TAC. The one or more processors are further configured to receive, during operation of the timer and by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The one or more processors are further configured to determine, based on the second TAC indicating the second TAG, whether to reset the timer.

In a sixth aspect, an apparatus includes means for receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The apparatus further includes means for initiating operation of a timer of the UE in response to receiving the first TAC. The apparatus further includes means for receiving, during operation of the timer by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The apparatus further includes means for determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In a seventh aspect, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG. The operations further include, in response to receiving the first TAC, initiating operation of a timer of the UE. The operations further include, during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG. The operations further include determining, based on the second TAC indicating the second TAG, whether to reset the timer.

In an eighth aspect, a method of wireless communication includes, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiating operation of a first timer of the UE. The method further includes, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE. The method further includes, in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.

In a ninth aspect alone or in combination with the eighth aspect, the UE detects expiration of the first timer and the second timer, and the UE performs the one or more timer expiration operations based on detecting expiration of the first timer and the second timer.

In a tenth aspect alone or in combination with one or more of the eighth through ninth aspects, the serving cell is included in a PTAG of the UE.

In an eleventh aspect alone or in combination with one or more of the eighth through tenth aspects, performing the one or more timer expiration operations includes one or more of: flushing HARQ buffers associated with serving cells of the UE; transmitting a RRC request to release one or more PUCCH configurations associated with serving cells of the UE;transmitting an RRC request to release one or more SRS configurations associated with the UE; clearing one or more downlink assignments, clearing one or more configured uplink grants, or both; clearing one or more PUSCH configurations for semi-persistent CSI reporting; determining that each running timer of the UE is expired; or maintaining a timing advance value for each TAG associated with the UE.

In a twelfth aspect alone or in combination with one or more of the eighth through eleventh aspects, the serving cell is included in a STAG of the UE.

In a thirteenth aspect alone or in combination with one or more of the eighth through twelfth aspects, performing the one or more timer expiration operations includes one or more of: flushing HARQ buffers associated with serving cells of the STAG; transmitting a RRC request to release one or more PUCCH configurations associated with serving cells of the STAG; transmitting an RRC request to release one or more SRS configurations associated with serving cells of the STAG; clearing one or more downlink assignments for serving cells of the STAG, clearing one or more configured uplink grants for the serving cells of the STAG, or both; clearing one or more PUSCH configurations for semi-persistent CSI reporting associated with serving cells of the STAG; or maintaining a timing advance value associated with the STAG.

In an fourteenth aspect alone or in combination with one or more of the eighth through thirteenth aspects, the UE detects expiration one or both of the first timer and the second timer, and the UE performs the one or more timer expiration operations based on detecting expiration of one or both of the first timer and the second timer.

In a fifteenth aspect alone or in combination with one or more of the eighth through fourteenth aspects, the serving cell is included in a PTAG of the UE.

In a sixteenth aspect alone or in combination with one or more of the eighth through fifteenth aspects, performing the one or more timer expiration operations includes one or more of: flushing HARQ buffers associated with serving cells of the UE; transmitting a RRC request to release one or more PUCCH configurations associated with serving cells of the UE; transmitting an RRC request to release one or more SRS configurations associated with the UE; clearing one or more downlink assignments, clearing one or more configured uplink grants, or both; clearing one or more PUSCH configurations for semi-persistent CSI reporting; determining that each running timer of the UE is expired; or maintaining a timing advance value for each TAG associated with the UE.

In a seventeenth aspect alone or in combination with one or more of the eighth through sixteenth aspects, the serving cell is included in a STAG of the UE.

In an eighteenth aspect alone or in combination with one or more of the eighth through seventeenth aspects, performing the one or more timer expiration operations includes one or more of: flushing HARQ buffers associated with serving cells of the STAG; transmitting a RRC request to release one or more PUCCH configurations associated with serving cells of the STAG; transmitting an RRC request to release one or more SRS configurations associated with serving cells of the STAG; clearing one or more downlink assignments for serving cells of the STAG, clearing one or more configured uplink grants for the serving cells of the STAG, or both; clearing one or more PUSCH configurations for semi- persistent CSI reporting associated with serving cells of the STAG; or maintaining a timing advance value associated with the STAG.

In a nineteenth aspect alone or in combination with one or more of the eighth through eighteenth aspects, the UE detects expiration of the first timer without detecting expiration of the second timer, the first timer is associated with a particular antenna panel of the UE, and the UE performs the one or more timer expiration operations for the particular antenna panel based on detecting expiration of the first timer without detecting expiration of the second timer.

In a twentieth aspect alone or in combination with one or more of the eighth through nineteenth aspects, performing the one or more timer expiration operations includes one or more of: flushing HARQ buffers associated with a panel identifier (ID) of the particular antenna panel; transmitting a RRC request to release one or more PUCCH configurations associated with the panel ID; transmitting an RRC request to release one or more SRS configurations associated with the panel ID; clearing one or more downlink assignments associated with the panel ID, clearing one or more configured uplink grants associated with the panel ID, or both; clearing one or more PUSCH configurations for semi-persistent CSI reporting associated with the panel ID; or maintaining a timing advance value associated with the panel ID.

In an twenty-first aspect alone or in combination with one or more of the eighth through twentieth aspects, the method further includes determining the panel ID using one or more of a TAG ID, a CORESET pool index ID, or an SRS resource set ID.

In a twenty-second aspect alone or in combination with one or more of the eighth through twenty-first aspects, the first TAC is received from a first TRP of the serving cell, and the second TAC is received from a second TRP of the serving cell.

In a twenty-third aspect, the apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiate operation of a first timer of the UE. The one or more processors are further configured to, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiate operation of a second timer of the UE. The one or more processors are further configured to, in response to detecting expiration of one or both of the first timer or the second timer, perform, by the UE, one or more timer expiration operations.

In a twenty-fourth aspect, an apparatus includes means for initiating, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, operation of a first timer of the UE. The apparatus further includes means for initiating, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, operation of a second timer of the UE. The apparatus further includes means for performing, in response to detecting expiration of one or both of the first timer or the second timer, one or more timer expiration operations by the UE.

In a twenty-fifth aspect, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include, in response to receiving, by a UE from a serving cell, a first TAC associated with a first antenna panel of the UE and with a first TAG, initiating operation of a first timer of the UE. The operations further include, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE. The operations further include, in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.

In a twenty-sixth aspect, a method of wireless communication includes transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE. The first TAC is associated with a first TAG. The method further includes transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE. The second TAC is associated with a second TAG.

In an twenty-seventh aspect alone or in combination with the twenty-sixth aspect, the UE includes a timer that is shared between the first TAG and the second TAG, and the UE resets the timer based on the second TAC indicating the second TAG.

In an twenty-eighth aspect alone or in combination with one or more of the twenty-sixth through twenty-seventh aspects, the UE includes a first timer associated with the first TAG and further includes a second timer associated with the second TAG, and the UE resets the second timer based on the second TAC indicating the second TAG and without resetting the timer based on the second TAC.

In an twenty-ninth aspect alone or in combination with one or more of the twenty-sixth through twenty-eighth aspects, the UE performs one or more timer expiration operations based on detecting expiration of a first timer associated with the first TAG and further based on detecting expiration of a second timer associated with the second TAG.

In an thirtieth aspect alone or in combination with one or more of the twenty-sixth through twenty-ninth aspects, the UE performs one or more timer expiration operations based on detecting expiration of one or both of a first timer associated with the first TAG or a second timer associated with the second TAG timer.

In an thirty-first aspect alone or in combination with one or more of the twenty-sixth through thirtieth aspects, the UE performs one or more timer expiration operations for a particular antenna panel based on detecting expiration of a first timer associated with the first TAG and without detecting expiration of a second timer associated with the second TAG.

In an thirty-second aspect alone or in combination with one or more of the twenty-sixth through thirty-first aspects, one of the first TAG and the second TAG corresponds to a PTAG of the UE, and the other of the first TAG and the second TAG corresponds to an STAG of the UE.

In a thirty-third aspect, an apparatus includes a memory and one or more processors coupled to the memory. The one or more processors are configured to transmit, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The one or more processors are further configured to transmit, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG.

In a thirty-fourth aspect, an apparatus includes means for transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The apparatus further includes means for transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG.

In a thirty-fifth aspect, a non-transitory computer-readable medium stores instructions executable by a processor to perform operations. The operations include transmitting, by a first TRP of a base station, a first TAC to a first antenna panel of the UE, where the first TAC is associated with a first TAG. The operations further include transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, where the second TAC is associated with a second TAG.

Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

One or more functional blocks and modules described herein may include processors, electronics devices, hardware devices, electronics components, logical circuits, memories, software codes, firmware codes, etc., or any combination thereof.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and operations described in connection with the disclosure herein may be implemented as electronic hardware, computer software, or combinations of both. To illustrate, various components, blocks, modules, circuits, and operations have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design parameters associated with the particular application. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure. Skilled artisans will also readily recognize that the order or combination of components, methods, or interactions that are described herein are merely examples and that the components, methods, or interactions of the various aspects of the present disclosure may be combined or performed in ways other than those illustrated and described herein.

The various illustrative logical blocks, modules, and circuits described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The operations of a process or method described in connection with the disclosure herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

In one or more exemplary designs, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. Computer-readable storage media may be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, a connection may be properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL) , then the coaxial cable, fiber optic cable, twisted pair, or DSL, are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD) , laser disc, optical disc, digital versatile disc (DVD) , floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

As used herein, including in the claims, the term “and/or, ” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination. Also, as used herein, including in the claims, “or” as used in a list of items prefaced by “at least one of” indicates a disjunctive list such that, for example, a list of “at least one of A, B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) or any of these in any combination thereof.

The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

A method of wireless communication, comprising:

receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) ;

in response to receiving the first TAC, initiating operation of a timer of the UE;

during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG; and

determining, based on the second TAC indicating the second TAG, whether to reset the timer.
The method of claim 1, wherein the timer is shared between the first TAG and the second TAG, and further comprising resetting the timer based on the second TAC indicating the second TAG.
The method of claim 1, wherein the timer is associated with the first TAG, wherein a second timer of the UE is associated with the second TAG, and further comprising resetting the second timer based on the second TAC indicating the second TAG and without resetting the timer based on the second TAC.
The method of claim 1, wherein the first TAC is received from a first transmission and reception point (TRP) of the serving cell, and wherein the second TAC is received from a second TRP of the serving cell.
An apparatus comprising:

a memory; and

one or more processors coupled to the memory and configured to:

receive, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) ;

in response to receiving the first TAC, initiate operation of a timer of the UE;

during operation of the timer, receive, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG; and

determine, based on the second TAC indicating the second TAG, whether to reset the timer.
An apparatus comprising:

means for receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) ;

means for initiating operation of a timer of the UE in response to receiving the first TAC;

means for receiving, during operation of the timer by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG; and

means for determining, based on the second TAC indicating the second TAG, whether to reset the timer.
A non-transitory computer-readable medium storing instructions executable by a processor to perform operations, the operations comprising:

receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) ;

in response to receiving the first TAC, initiating operation of a timer of the UE;

during operation of the timer, receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG; and

determining, based on the second TAC indicating the second TAG, whether to reset the timer.
A method of wireless communication, comprising:

in response to receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) , initiating operation of a first timer of the UE;

in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE; and

in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.
The method of claim 8, wherein the UE detects expiration of the first timer and the second timer, and wherein the UE performs the one or more timer expiration operations based on detecting expiration of the first timer and the second timer.
The method of claim 9, wherein the serving cell is included in a primary timing advance group (PTAG) of the UE.
The method of claim 10, wherein performing the one or more timer expiration operations includes one or more of:

flushing hybrid automatic repeat request (HARQ) buffers associated with serving cells of the UE;

transmitting a radio resource control (RRC) request to release one or more physical uplink control channel (PUCCH) configurations associated with serving cells of the UE;

transmitting an RRC request to release one or more sounding reference signal (SRS) configurations associated with the UE;

clearing one or more downlink assignments, clearing one or more configured uplink grants, or both;

clearing one or more physical uplink shared channel (PUSCH) configurations for semi-persistent channel state information (CSI) reporting;

determining that each running timer of the UE is expired; or

maintaining a timing advance value for each TAG associated with the UE.
The method of claim 9, wherein the serving cell is included in a secondary timing advance group (STAG) of the UE.
The method of claim 12, wherein performing the one or more timer expiration operations includes one or more of:

flushing hybrid automatic repeat request (HARQ) buffers associated with serving cells of the STAG;

transmitting a radio resource control (RRC) request to release one or more physical uplink control channel (PUCCH) configurations associated with serving cells of the STAG;

transmitting an RRC request to release one or more sounding reference signal (SRS) configurations associated with serving cells of the STAG;

clearing one or more downlink assignments for serving cells of the STAG, clearing one or more configured uplink grants for the serving cells of the STAG, or both;

clearing one or more physical uplink shared channel (PUSCH) configurations for semi-persistent channel state information (CSI) reporting associated with serving cells of the STAG; or

maintaining a timing advance value associated with the STAG.
The method of claim 8, wherein the UE detects expiration one or both of the first timer and the second timer, and wherein the UE performs the one or more timer expiration operations based on detecting expiration of one or both of the first timer and the second timer.
The method of claim 14, wherein the serving cell is included in a primary timing advance group (PTAG) of the UE.
The method of claim 15, wherein performing the one or more timer expiration operations includes one or more of:

flushing hybrid automatic repeat request (HARQ) buffers associated with serving cells of the UE;

transmitting a radio resource control (RRC) request to release one or more physical uplink control channel (PUCCH) configurations associated with serving cells of the UE;

transmitting an RRC request to release one or more sounding reference signal (SRS) configurations associated with the UE;

clearing one or more downlink assignments, clearing one or more configured uplink grants, or both;

clearing one or more physical uplink shared channel (PUSCH) configurations for semi-persistent channel state information (CSI) reporting;

determining that each running timer of the UE is expired; or

maintaining a timing advance value for each TAG associated with the UE.
The method of claim 14, wherein the serving cell is included in a secondary timing advance group (STAG) of the UE.
The method of claim 17, wherein performing the one or more timer expiration operations includes one or more of:

flushing hybrid automatic repeat request (HARQ) buffers associated with serving cells of the STAG;

transmitting a radio resource control (RRC) request to release one or more physical uplink control channel (PUCCH) configurations associated with serving cells of the STAG;

transmitting an RRC request to release one or more sounding reference signal (SRS) configurations associated with serving cells of the STAG;

clearing one or more downlink assignments for serving cells of the STAG, clearing one or more configured uplink grants for the serving cells of the STAG, or both;

clearing one or more physical uplink shared channel (PUSCH) configurations for semi-persistent channel state information (CSI) reporting associated with serving cells of the STAG; or

maintaining a timing advance value associated with the STAG.
The method of claim 8, wherein the UE detects expiration of the first timer without detecting expiration of the second timer, wherein the first timer is associated with a particular antenna panel of the UE, and wherein the UE performs the one or more timer expiration operations for the particular antenna panel based on detecting expiration of the first timer without detecting expiration of the second timer.
The method of claim 19, wherein performing the one or more timer expiration operations includes one or more of:

flushing hybrid automatic repeat request (HARQ) buffers associated with a panel identifier (ID) of the particular antenna panel;

transmitting a radio resource control (RRC) request to release one or more physical uplink control channel (PUCCH) configurations associated with the panel ID;

transmitting an RRC request to release one or more sounding reference signal (SRS) configurations associated with the panel ID;

clearing one or more downlink assignments associated with the panel ID, clearing one or more configured uplink grants associated with the panel ID, or both;

clearing one or more physical uplink shared channel (PUSCH) configurations for semi-persistent channel state information (CSI) reporting associated with the panel ID; or

maintaining a timing advance value associated with the panel ID.
The method of claim 20, further comprising determining the panel ID using one or more of a TAG ID, a control resource set (CORESET) pool index ID, or an SRS resource set ID.
The method of claim 8, wherein the first TAC is received from a first transmission and reception point (TRP) of the serving cell, and wherein the second TAC is received from a second TRP of the serving cell.
An apparatus comprising:

a memory; and

one or more processors coupled to the memory and configured to:

in response to receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) , initiate operation of a first timer of the UE;

in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiate operation of a second timer of the UE; and

in response to detecting expiration of one or both of the first timer or the second timer, perform, by the UE, one or more timer expiration operations.
An apparatus comprising:

means for initiating, in response to receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) , operation of a first timer of the UE;

means for initiating, in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, operation of a second timer of the UE; and

means for performing, in response to detecting expiration of one or both of the first timer or the second timer, one or more timer expiration operations by the UE.
A non-transitory computer-readable medium storing instructions executable by a processor to perform operations, the operations comprising:

in response to receiving, by a user equipment (UE) from a serving cell, a first timing advance command (TAC) associated with a first antenna panel of the UE and with a first timing advance group (TAG) , initiating operation of a first timer of the UE;

in response to receiving, by the UE from the serving cell, a second TAC associated with a second antenna panel of the UE and with a second TAG, initiating operation of a second timer of the UE; and

in response to detecting expiration of one or both of the first timer or the second timer, performing, by the UE, one or more timer expiration operations.
A method of wireless communication, comprising:

transmitting, by a first transmission and reception point (TRP) of a base station, a first timing advance command (TAC) to a first antenna panel of the UE, wherein the first TAC is associated with a first timing advance group (TAG) ; and

transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, wherein the second TAC is associated with a second TAG.
The method of claim 26, wherein the UE includes a timer that is shared between the first TAG and the second TAG, and wherein the UE resets the timer based on the second TAC indicating the second TAG.
The method of claim 26, wherein the UE includes a first timer associated with the first TAG and further includes a second timer associated with the second TAG, and wherein the UE resets the second timer based on the second TAC indicating the second TAG and without resetting the timer based on the second TAC.
The method of claim 26, wherein the UE performs one or more timer expiration operations based on detecting expiration of a first timer associated with the first TAG and further based on detecting expiration of a second timer associated with the second TAG.
The method of claim 26, wherein the UE performs one or more timer expiration operations based on detecting expiration of one or both of a first timer associated with the first TAG or a second timer associated with the second TAG timer.
The method of claim 26, wherein the UE performs one or more timer expiration operations for a particular antenna panel based on detecting expiration of a first timer associated with the first TAG and without detecting expiration of a second timer associated with the second TAG.
The method of claim 26, wherein one of the first TAG and the second TAG corresponds to a primary TAG (PTAG) of the UE, and wherein the other of the first TAG and the second TAG corresponds to an STAG of the UE.
An apparatus comprising:

a memory; and

one or more processors coupled to the memory and configured to:

transmit, by a first transmission and reception point (TRP) of a base station, a first timing advance command (TAC) to a first antenna panel of the UE, wherein the first TAC is associated with a first timing advance group (TAG) ; and

transmit, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, wherein the second TAC is associated with a second TAG.
An apparatus comprising:

means for transmitting, by a first transmission and reception point (TRP) of a base station, a first timing advance command (TAC) to a first antenna panel of the UE, wherein the first TAC is associated with a first timing advance group (TAG) ; and

means for transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, wherein the second TAC is associated with a second TAG.
A non-transitory computer-readable medium storing instructions executable by a processor to perform operations, the operations comprising:

transmitting, by a first transmission and reception point (TRP) of a base station, a first timing advance command (TAC) to a first antenna panel of the UE, wherein the first TAC is associated with a first timing advance group (TAG) ; and

transmitting, by a second TRP of the base station, a second TAC to a second antenna panel of the UE, wherein the second TAC is associated with a second TAG.