WO2023159454A1

WO2023159454A1 - Timing advance group (tag) configurations for multiple transmission-reception (mtrp) communications

Info

Publication number: WO2023159454A1
Application number: PCT/CN2022/077839
Authority: WO
Inventors: Shaozhen GUO; Mostafa KHOSHNEVISAN; Jing Sun; Xiaoxia Zhang; Fang Yuan; Yan Zhou; Tao Luo; Peter Gaal
Original assignee: Qualcomm Incorporated
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2023-08-31

Abstract

A method for wireless communication performed by a first wireless communication device may include: communicating a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and communicating a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Description

TIMING ADVANCE GROUP (TAG) CONFIGURATIONS FOR MULTIPLE TRANSMISSION-RECEPTION (MTRP) COMMUNICATIONS

INTRODUCTION

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . A wireless multiple-access communications system may include a number of base stations (BSs) , each simultaneously supporting communications for multiple communication devices, which may be otherwise known as user equipment (UE) .

To meet the growing demands for expanded mobile broadband connectivity, wireless communication technologies are advancing from the long term evolution (LTE) technology to a next generation new radio (NR) technology, which may be referred to as 5 ^th Generation (5G) . For example, NR is designed to provide a lower latency, a higher bandwidth or a higher throughput, and a higher reliability than LTE. NR is designed to operate over a wide array of spectrum bands, for example, from low-frequency bands below about 1 gigahertz (GHz) and mid-frequency bands from about 1 GHz to about 6 GHz, to high-frequency bands such as millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, from licensed spectrum to unlicensed and shared spectrum. Spectrum sharing enables operators to opportunistically aggregate spectrums to dynamically support high-bandwidth services. Spectrum sharing can extend the benefit of NR technologies to operating entities that may not have access to a licensed spectrum.

It may be desirable or advantageous to align uplink (UL) communications at a BS based on a BS timing configuration. For example, in orthogonal multiple access in which different UEs may communicate in consecutive time resources (e.g., slots) , and/or where different UEs may be configured to communicate with the BS simultaneously but in different frequency resources (e.g., carriers, subcarriers) , proper timing alignment of the UEs with the BS may reduce or avoid intra-cell interference. The UEs may compensate for the delay (e.g., propagation delay) of UL communications transmitted to the BS by determining and applying a timing advance to the UL communications.

In a mTRP communication scenario, a UE may be scheduled to communicate with one or more transmission reception points (TRPs) . In some aspects, the TRPs may be at different physical locations. Thus, the UE may experience different propagation delays for communications to and/or from the different TRPs. Accordingly, the UE may be configured to apply different timing advances to communications between the UE and different TRPs. To determine a timing advance, at least one reference cell may be selected or determined. For example, the UE may be configured for carrier aggregation (CA) to communication with the multiple TRPs using a plurality of cells. In single-DCI mTRP communications, a DCI from one of the TRPs may schedule communications for each of a plurality of TRPs. In multi-DCI (mDCI) mTRP (mTRP) communications, each TRP may transmit DCI to the UE to schedule communications.

BRIEF SUMMARY OF SOME EXAMPLES

The following summarizes some aspects of the present disclosure to provide a basic understanding of the discussed technology. This summary is not an extensive overview of all contemplated features of the disclosure and is intended neither to identify key or critical elements of all aspects of the disclosure nor to delineate the scope of any or all aspects of the disclosure. Its sole purpose is to present some concepts of one or more aspects of the disclosure in summary form as a prelude to the more detailed description that is presented later.

One aspect of the present disclosure includes a method of wireless communication performed by a first wireless communication device. The method may include: communicating, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and communicating, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, and wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Another aspect of the present disclosure includes a first wireless communication device comprising a processor and a transceiver in communication with the processor. The first wireless communication device may be configured to: communicate, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and communicate, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Another aspect of the present disclosure includes a non-transitory, computer-readable medium having program code recorded thereon. The program code may include instructions executable by a first wireless communication device to cause a second wireless communication device to: communicate, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and communicate, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Another aspect of the present disclosure comprises a first wireless communication device. The first wireless communication device may include: means for communicating, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and means for communicating, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Other aspects, features, and embodiments will become apparent to those of ordinary skill in the art, upon reviewing the following description of specific, exemplary aspects in conjunction with the accompanying figures. While features may be discussed relative to certain aspects and figures below, all aspects can include one or more of the advantageous features discussed herein. In other words, while one or more aspects may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various aspects discussed herein. In similar fashion, while exemplary aspects may be discussed below as device, system, or method aspects it should be understood that such exemplary aspects can be implemented in various devices, systems, and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a wireless communication network according to some aspects of the present disclosure.

FIG. 2 illustrates a communication scenario with a reconfigurable intelligent surface according to some aspects of the present disclosure.

FIG. 3 is a timing diagram for timing advance in a communication scenario, according to aspects of the present disclosure.

FIG. 4 illustrates a transmission frame for a communication network according to some embodiments of the present disclosure.

FIG. 5 is a signaling diagram of a multiple transmission-reception point (mTRP) communication method according to some aspects of the present disclosure.

FIG. 6A is a diagram illustrating a scheme for a downlink (DL) control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 6B is a diagram illustrating a plurality of DL control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 7A is a diagram illustrating a scheme for a DL control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 7B is a diagram illustrating a plurality of DL control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 8A is a diagram illustrating a scheme for a DL control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 8B is a diagram illustrating a plurality of DL control channel and timing advance configurations in a mTRP communication scenario according to some aspects of the present disclosure.

FIG. 9 illustrates a block diagram of a base station (BS) according to some aspects of the present disclosure.

FIG. 10 illustrates a block diagram of a user equipment (UE) according to some aspects of the present disclosure.

FIG. 11 is a flow diagram of a wireless communication method according to some aspects of the present disclosure.

FIG. 12 is a diagram illustrating an example disaggregated BS architecture according to some aspects of the present disclosure.

DETAILED DESCRIPTION

The detailed description set forth below, in connection with the appended drawings, is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some aspects, well-known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

This disclosure relates generally to wireless communications systems, also referred to as wireless communications networks. In various aspects, the techniques and apparatus may be used for 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, Global System for Mobile Communications (GSM) networks, 5 ^th 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) , Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, flash-OFDM and the like. UTRA, E-UTRA, and 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 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-Aare 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.

A 5G NR communication system 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 5, 10, 20 MHz, and the like bandwidth (BW) . 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 BW. 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 BW. Finally, for various deployments transmitting with mmWave components at a TDD of 28 GHz, subcarrier spacing may occur with 120 kHz over a 500 MHz BW. In certain aspects, frequency bands for 5G NR are separated into multiple different frequency ranges, a frequency range one (FR1) , a frequency range two (FR2) , and FR2x. FR1 bands include frequency bands at 7 GHz or lower (e.g., between about 410 MHz to about 7125 MHz) . FR2 bands include frequency bands in mmWave ranges between about 24.25 GHz and about 52.6 GHz. FR2x bands include frequency bands in mmWave ranges between about 52.6 GHz to about 71 GHz. The mmWave bands may have a shorter range, but a higher bandwidth than the FR1 bands. Additionally, 5G NR may support different sets of subcarrier spacing for different frequency ranges.

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 UL/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 UL/downlink that may be flexibly configured on a per-cell basis to dynamically switch between UL and downlink to meet the current traffic needs.

Deployment of communication systems, such as 5G new radio (NR) systems, may be arranged in multiple manners with various components or constituent parts. In a 5G NR system, or network, a network node, a network entity, a mobility element of a network, a radio access network (RAN) node, a core network node, a network element, or a network equipment, such as a base station (BS) , or one or more units (or one or more components) performing base station functionality, may be implemented in an aggregated or disaggregated architecture. For example, a BS (such as a Node B (NB) , evolved NB (eNB) , NR BS, 5G NB, access point (AP) , a transmit receive point (TRP) , or a cell, etc. ) may be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a disaggregated base station.

An aggregated base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A disaggregated base station may be configured to utilize a protocol stack that is physically or logically distributed among two or more units (such as one or more central or centralized units (CUs) , one or more distributed units (DUs) , or one or more radio units (RUs) ) . In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed throughout one or multiple other RAN nodes. The DUs may be implemented to communicate with one or more RUs. Each of the CU, DU and RU also can be implemented as virtual units, i.e., a virtual central unit (VCU) , a virtual distributed unit (VDU) , or a virtual radio unit (VRU) .

Base station-type operation or network design may consider aggregation characteristics of base station functionality. For example, disaggregated base stations may be utilized in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (such as the network configuration sponsored by the O-RAN Alliance) ) , or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN) ) . Disaggregation may include distributing functionality across two or more units at various physical locations, as well as distributing functionality for at least one unit virtually, which can enable flexibility in network design. The various units of the disaggregated base station, or disaggregated RAN architecture, can be configured for wired or wireless communication with at least one other unit.

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.

It may be desirable or advantageous to align uplink (UL) communications at a BS based on a BS timing configuration. For example, in orthogonal multiple access in which different UEs may communicate in consecutive time resources (e.g., slots) and/or where different UEs may be configured to communicate with the BS simultaneously but in different frequency resources (e.g., carriers, subcarriers) , proper timing alignment of the UEs with the BS may reduce or avoid intra-cell interference. The UEs may compensate for the delay (e.g., propagation delay) of UL communications transmitted to the BS by determining and applying a timing advance to the UL communications. However, each UE served by the BS may be at a different distance away from the BS and/or have different obstructions between the UE and the BS. Therefore, the UL communications from each UE may have a different propagation delay. Accordingly, one or more of the UEs may autonomously and/or continuously update its timing advance to ensure proper timing alignment with the BS. In other aspects, one or more of the UEs may determine or update the timing advance based on configurations and/or indications provided by the BS. The BS may configure each of the UEs in the network with a timing advance configuration. The timing advance configuration may include or indicate a timing advance adjustment that can be used by the UE. The UE may determine a dynamic or autonomous timing advance to apply to UL communications based on the timing advance adjustment. In some instances, the timing advance applied by each UE may be based on a sum of the timing advance adjustment received from the BS and a dynamic or autonomous timing advance determined by the UE.

The UEs may be configured to update the timing advance within a set of parameters. For example, the timing advance configuration may include or indicate a maximum autonomous timing advance adjustment that represents the maximum adjustment to a timing advance a UE can make in a given time period. Further, the UEs and BS may be configured or required to satisfy a maximum error or deviation for proper time alignment with the BS. The maximum error or deviation and/or the maximum autonomous timing advance adjustment may be based on a frequency range of the BS-UE communications (e.g., FR1, FR2) , the subcarrier spacing of the BS-UE communications, and/or other factors.

In a mTRP communication scenario, a UE may be scheduled to communicate with one or more transmission reception points (TRPs) . In some aspects, the TRPs may be at different physical locations. Thus, the UE may experience different propagation delays for communications to and/or from the different TRPs. Accordingly, the UE may be configured to apply different timing advances to communications between the UE and different TRPs. To determine a timing advance, at least one reference cell may be selected or determined. For example, the UE may be configured for carrier aggregation (CA) to communication with the multiple TRPs using a plurality of cells. In single-DCI mTRP communications, a DCI from one of the TRPs may schedule communications for each of a plurality of TRPs. In multi-DCI (mDCI) mTRP (mTRP) communications, each TRP may transmit DCI to the UE to schedule communications. In some aspects, one or more of the serving cells may be configured for mDCI mTRP communications and one or more cells may be configured for single-DCI mTRP communications or single TRP communications. A cell may be configured for mDCI mTRP communications if the cell configuration indicates two CORESET pool index values and two timing advance groups (TAGs) . For example, a mDCI mTRP cell may be configured with two CORESET pool index values and two TAG indicators. A single-DCI mTRP cell or single-TRP cell configuration may indicate a single TAG indicator and/or a single CORESET pool index value. When a cell is configured for mDCI mTRP communications, UL signals on the cell may be transmitted to one of multiple TRPs. For example, the mDCI mTRP cell may be configured with multiple TAGs to allow for different timing advance commands to be applied to communications for the different TRPs. Further, the UE may be configured with other cells that are configured with one or more TAG indicators and one or more CORESET pool indexes. However, not all cells may be configured with the same combinations of TAG indicators and/or CORESET pool index configurations. Further, not all serving cells may be configured for mDCI mTRP communications. In some aspects, two serving cells may be configured with at least one common CORESET pool index, but may have different TAG configurations. For example, a UE may have two configured serving cells, where each serving cell is configured with a first CORESET pool index and a second CORESET pool index. However, the serving cells may have different configurations of TAGs. Accordingly, if a UE detects a DCI scheduling communications in a CORESET associated with the first CORESET pool index, the first and second cells may be configured with different TAGs for the CORESET pool. It may be desirable to provide intra-cell and/or inter-cell association rules for cell configurations such that the wireless communication devices can determine and apply a suitable timing advance for UL communications in an mDCI mTRP communication scenario.

The present disclosure describes systems, schemes, and methods for configuring two or more cells based on one or more timing advance (TA) association rules or configurations. In some aspects, a wireless communication scheme may include communicating a first cell configuration indicating a first CORESET pool index associated with a first TAG by a first association and indicating a second CORESET pool index associated with a second TAG by a second association. The scheme may further include communicating a second cell configuration indicating a third CORESET pool index associated with a third TAG by a third association. The first, second, and third associations may be based on a TA association configuration. In some aspects, the TA association configuration may be semi-statically configured. In other aspects, the TA association configuration may be fixed or hardcoded. The TA association configuration may define one or more association rules for the cell configurations mentioned above. For example, the TA association configuration may indicate that the third association is the same as one of the first association or the second association. In some instances, the TA association configuration may indicate that the third TAG indicator is different from both the first TAG indicator and the second TAG indicator.

The schemes and mechanisms of the present disclosure advantageously facilitate mDCI based mTRP communications with carrier aggregation (CA) . In this regard, the TA configuration association schemes may define relationships or rules for CORESET configurations and TA configurations when a wireless communication device is configured to communicate using multiple serving cells. Accordingly, additional communication flexibility may be provided, allowing for more robust communications and higher throughput while maintaining sufficient time domain orthogonality for UL communications. Thus, using the schemes and mechanisms of the present disclosure, throughput and efficiency of the network may be increased, latency may be decreased, and user experience may be improved.

FIG. 1 illustrates a wireless communication network 100 according to some aspects of the present disclosure. The network 100 may be a 5G network. The network 100 includes a number of base stations (BSs) 105 (individually labeled as 105a, 105b, 105c, 105d, 105e, and 105f) and other network entities. A BS 105 may be a station that communicates with UEs 115 (individually labeled as 115a, 115b, 115c, 115d, 115e, 115f, 115g, 115h, and 115k) and may also be referred to as an evolved node B (eNB) , a next generation eNB (gNB) , an access point, and the like. Each BS 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 BS 105 and/or a BS subsystem serving the coverage area, depending on the context in which the term is used.

A BS 105 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 BS for a macro cell may be referred to as a macro BS. A BS for a small cell may be referred to as a small cell BS, a pico BS, a femto BS or a home BS. In the example shown in FIG. 1, the

BSs

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

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

The UEs 115 are dispersed throughout the wireless network 100, and each UE 115 may be stationary or mobile. A UE 115 may also be referred to as a terminal, a mobile station, a subscriber unit, a station, or the like. A UE 115 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 115 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, the UEs 115 that do not include UICCs may also be referred to as IoT devices or internet of everything (IoE) devices. The UEs 115a-115d are examples of mobile smart phone-type devices accessing network 100. A UE 115 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. The UEs 115e-115h are examples of various machines configured for communication that access the network 100. The UEs 115i-115k are examples of vehicles equipped with wireless communication devices configured for communication that access the network 100. A UE 115 may be able to communicate with any type of the BSs, whether macro BS, small cell, or the like. In FIG. 1, a lightning bolt (e.g., communication links) indicates wireless transmissions between a UE 115 and a serving BS 105, which is a BS designated to serve the UE 115 on the downlink (DL) and/or uplink (UL) , desired transmission between BSs 105, backhaul transmissions between BSs, or sidelink transmissions between UEs 115.

In operation, the BSs 105a-105c may serve the

UEs

115a and 115b using 3D beamforming and coordinated spatial techniques, such as coordinated multipoint (CoMP) or multi-connectivity. The macro BS 105d may perform backhaul communications with the BSs 105a-105c, as well as small cell, the BS 105f. The macro BS 105d may also transmits multicast services which are subscribed to and received by the

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.

The BSs 105 may also communicate with a core network. The core network may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. At least some of the BSs 105 (e.g., which may be an example of a gNB or an access node controller (ANC) ) may interface with the core network through backhaul links (e.g., NG-C, NG-U, etc. ) and may perform radio configuration and scheduling for communication with the UEs 115. In various examples, the BSs 105 may communicate, either directly or indirectly (e.g., through core network) , with each other over backhaul links (e.g., X1, X2, etc. ) , which may be wired or wireless communication links.

The network 100 may also support mission critical communications with ultra-reliable and redundant links for mission critical devices, such as the UE 115e, which may be a drone. Redundant communication links with the UE 115e may include links from the

macro BSs

105d and 105e, as well as links from the small cell BS 105f. Other machine type devices, such as the UE 115f (e.g., a thermometer) , the UE 115g (e.g., smart meter) , and UE 115h (e.g., wearable device) may communicate through the network 100 either directly with BSs, such as the small cell BS 105f, and the macro BS 105e, or in multi-action-size configurations by communicating with another user device which relays its information to the network, such as the UE 115f communicating temperature measurement information to the smart meter, the UE 115g, which is then reported to the network through the small cell BS 105f. The network 100 may also provide additional network efficiency through dynamic, low-latency TDD/FDD communications, such asV2V, V2X, C-V2X communications between a

UE

115i, 115j, or 115k and other UEs 115, and/or vehicle-to-infrastructure (V2I) communications between a

UE

115i, 115j, or 115k and a BS 105.

In some implementations, the network 100 utilizes OFDM-based waveforms for communications. An OFDM-based system may partition the system BW into multiple (K) orthogonal subcarriers, which are also commonly referred to as subcarriers, tones, bins, or the like. Each subcarrier may be modulated with data. In some aspects, the subcarrier spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may be dependent on the system BW. The system BW may also be partitioned into subbands. In other aspects, the subcarrier spacing and/or the duration of TTIs may be scalable.

In some aspects, the BSs 105 can assign or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RB) ) for downlink (DL) and uplink (UL) transmissions in the network 100. DL refers to the transmission direction from a BS 105 to a UE 115, whereas UL refers to the transmission direction from a UE 115 to a BS 105. The communication can be in the form of radio frames. A radio frame may be divided into a plurality of subframes or slots, for example, about 10. Each slot may be further divided into mini-slots. In a FDD mode, simultaneous UL and DL transmissions may occur in different frequency bands. For example, each subframe includes an UL subframe in an UL frequency band and a DL subframe in a DL frequency band. In a TDD mode, UL and DL transmissions occur at different time periods using the same frequency band. For example, a subset of the subframes (e.g., DL subframes) in a radio frame may be used for DL transmissions and another subset of the subframes (e.g., UL subframes) in the radio frame may be used for UL transmissions.

The DL subframes and the UL subframes can be further divided into several regions. For example, each DL or UL subframe may have pre-defined regions for transmissions of reference signals, control information, and data. Reference signals are predetermined signals that facilitate the communications between the BSs 105 and the UEs 115. For example, a reference signal can have a particular pilot pattern or structure, where pilot tones may span across an operational BW or frequency band, each positioned at a pre-defined time and a pre-defined frequency. For example, a BS 105 may transmit cell specific reference signals (CRSs) and/or channel state information –reference signals (CSI-RSs) to enable a UE 115 to estimate a DL channel. Similarly, a UE 115 may transmit sounding reference signals (SRSs) to enable a BS 105 to estimate an UL channel. Control information may include resource assignments and protocol controls. Data may include protocol data and/or operational data. In some aspects, the BSs 105 and the UEs 115 may communicate using self-contained subframes. A self-contained subframe may include a portion for DL communication and a portion for UL communication. A self-contained subframe can be DL-centric or UL-centric. A DL-centric subframe may include a longer duration for DL communication than for UL communication. an UL-centric subframe may include a longer duration for UL communication than for UL communication.

In some aspects, the network 100 may be an NR network deployed over a licensed spectrum. The BSs 105 can transmit synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) ) in the network 100 to facilitate synchronization. The BSs 105 can broadcast system information associated with the network 100 (e.g., including a master information block (MIB) , remaining system information (RMSI) , and other system information (OSI) ) to facilitate initial network access. In some aspects, the BSs 105 may broadcast the PSS, the SSS, and/or the MIB in the form of synchronization signal block (SSBs) and may broadcast the RMSI and/or the OSI over a physical downlink shared channel (PDSCH) . The MIB may be transmitted over a physical broadcast channel (PBCH) .

In some aspects, a UE 115 attempting to access the network 100 may perform an initial cell search by detecting a PSS from a BS 105. The PSS may enable synchronization of period timing and may indicate a physical layer identity value. The UE 115 may then receive a SSS. The SSS may enable radio frame synchronization, and may provide a cell identity value, which may be combined with the physical layer identity value to identify the cell. The PSS and the SSS may be located in a central portion of a carrier or any suitable frequencies within the carrier.

After receiving the PSS and SSS, the UE 115 may receive a MIB. The MIB may include system information for initial network access and scheduling information for RMSI and/or OSI. After decoding the MIB, the UE 115 may receive RMSI and/or OSI. The RMSI and/or OSI may include radio resource control (RRC) information related to random access channel (RACH) procedures, paging, control resource set (CORESET) for physical downlink control channel (PDCCH) monitoring, physical UL control channel (PUCCH) , physical UL shared channel (PUSCH) , power control, and SRS.

After obtaining the MIB, the RMSI and/or the OSI, the UE 115 can perform a random access procedure to establish a connection with the BS 105. In some examples, the random access procedure may be a four-step random access procedure. For example, the UE 115 may transmit a random access preamble and the BS 105 may respond with a random access response. The random access response (RAR) may include a detected random access preamble identifier (ID) corresponding to the random access preamble, timing advance (TA) information, an UL grant, a temporary cell-radio network temporary identifier (C-RNTI) , and/or a backoff indicator. Upon receiving the random access response, the UE 115 may transmit a connection request to the BS 105 and the BS 105 may respond with a connection response. The connection response may indicate a contention resolution. In some examples, the random access preamble, the RAR, the connection request, and the connection response can be referred to as message 1 (MSG1) , message 2 (MSG2) , message 3 (MSG3) , and message 4 (MSG4) , respectively. In some examples, the random access procedure may be a two-step random access procedure, where the UE 115 may transmit a random access preamble and a connection request in a single transmission and the BS 105 may respond by transmitting a random access response and a connection response in a single transmission.

After establishing a connection, the UE 115 and the BS 105 can enter a normal operation stage, where operational data may be exchanged. For example, the BS 105 may schedule the UE 115 for UL and/or DL communications. The BS 105 may transmit UL and/or DL scheduling grants to the UE 115 via a PDCCH. The scheduling grants may be transmitted in the form of DL control information (DCI) . The BS 105 may transmit a DL communication signal (e.g., carrying data) to the UE 115 via a PDSCH according to a DL scheduling grant. The UE 115 may transmit an UL communication signal to the BS 105 via a PUSCH and/or PUCCH according to an UL scheduling grant. The connection may be referred to as an RRC connection. When the UE 115 is actively exchanging data with the BS 105, the UE 115 is in an RRC connected state.

In an example, after establishing a connection with the BS 105, the UE 115 may initiate an initial network attachment procedure with the network 100. The BS 105 may coordinate with various network entities or fifth generation core (5GC) entities, such as an access and mobility function (AMF) , a serving gateway (SGW) , and/or a packet data network gateway (PGW) , to complete the network attachment procedure. For example, the BS 105 may coordinate with the network entities in the 5GC to identify the UE, authenticate the UE, and/or authorize the UE for sending and/or receiving data in the network 100. In addition, the AMF may assign the UE with a group of tracking areas (TAs) . Once the network attach procedure succeeds, a context is established for the UE 115 in the AMF. After a successful attach to the network, the UE 115 can move around the current TA. For tracking area update (TAU) , the BS 105 may request the UE 115 to update the network 100 with the UE 115’s location periodically. Alternatively, the UE 115 may only report the UE 115’s location to the network 100 when entering a new TA. The TAU allows the network 100 to quickly locate the UE 115 and page the UE 115 upon receiving an incoming data packet or call for the UE 115.

In some aspects, the BS 105 may communicate with a UE 115 using HARQ techniques to improve communication reliability, for example, to provide a URLLC service. The BS 105 may schedule a UE 115 for a PDSCH communication by transmitting a DL grant in a PDCCH. The BS 105 may transmit a DL data packet to the UE 115 according to the schedule in the PDSCH. The DL data packet may be transmitted in the form of a transport block (TB) . If the UE 115 receives the DL data packet successfully, the UE 115 may transmit a HARQ ACK to the BS 105. Conversely, if the UE 115 fails to receive the DL transmission successfully, the UE 115 may transmit a HARQ NACK to the BS 105. Upon receiving a HARQ NACK from the UE 115, the BS 105 may retransmit the DL data packet to the UE 115. The retransmission may include the same coded version of DL data as the initial transmission. Alternatively, the retransmission may include a different coded version of the DL data than the initial transmission. The UE 115 may apply soft combining to combine the encoded data received from the initial transmission and the retransmission for decoding. The BS 105 and the UE 115 may also apply HARQ for UL communications using substantially similar mechanisms as the DL HARQ.

In some aspects, the network 100 may operate over a system BW or a component carrier (CC) BW. The network 100 may partition the system BW into multiple BWPs (e.g., portions) . A BS 105 may dynamically assign a UE 115 to operate over a certain BWP (e.g., a certain portion of the system BW) . The assigned BWP may be referred to as the active BWP. The UE 115 may monitor the active BWP for signaling information from the BS 105. The BS 105 may schedule the UE 115 for UL or DL communications in the active BWP. In some aspects, a BS 105 may assign a pair of BWPs within the CC to a UE 115 for UL and DL communications. For example, the BWP pair may include one BWP for UL communications and one BWP for DL communications.

In some aspects, the network 100 may operate over a shared channel, which may include shared frequency bands and/or unlicensed frequency bands. For example, the network 100 may be an NR-U network operating over an unlicensed frequency band. In such an aspect, the BSs 105 and the UEs 115 may be operated by multiple network operating entities. To avoid collisions, the BSs 105 and the UEs 115 may employ a listen-before-talk (LBT) procedure to monitor for transmission opportunities (TXOPs) in the shared channel. A TXOP may also be referred to as COT. The goal of LBT is to protect reception at a receiver from interference. For example, a transmitting node (e.g., a BS 105 or a UE 115) may perform an LBT prior to transmitting in the channel. When the LBT passes, the transmitting node may proceed with the transmission. When the LBT fails, the transmitting node may refrain from transmitting in the channel.

An LBT can be based on energy detection (ED) or signal detection. For an energy detection-based LBT, the LBT results in a pass when signal energy measured from the channel is below a threshold. Conversely, the LBT results in a failure when signal energy measured from the channel exceeds the threshold. For a signal detection-based LBT, the LBT results in a pass when a channel reservation signal (e.g., a predetermined preamble signal) is not detected in the channel. Additionally, an LBT may be in a variety of modes. An LBT mode may be, for example, a category 4 (CAT4) LBT, a category 2 (CAT2) LBT, or a category 1 (CAT1) LBT. A CAT1 LBT is referred to a no LBT mode, where no LBT is to be performed prior to a transmission. A CAT2 LBT refers to an LBT without a random backoff period. For instance, a transmitting node may determine a channel measurement in a time interval and determine whether the channel is available or not based on a comparison of the channel measurement against a ED threshold. A CAT4 LBT refers to an LBT with a random backoff and a variable contention window (CW) . For instance, a transmitting node may draw a random number and backoff for a duration based on the drawn random number in a certain time unit.

In some aspects, one or more of the UEs 115 may be configured to communicate with two or more of the BSs 105 in a multi-transmission-reception point (mTRP) communication scenario. For example, a UE 115 may be configured with a first frequency band or cell, where the cell is configured for communications on more than one TRP. The UE 115 may receive DL communications (e.g., DCI, PDSCH, DL reference signals) from each TRP. The UE 115 may also transmit UL communications to one or more of the TRPs. Because the TRPs may be at different locations, different timing advances may be applied to UL communications for the TRPs, as explained below.

FIGS. 2 and 3 illustrate a multiple transmission-reception point (mTRP) communication scenario 200 according to aspects of the present disclosure. The communication scenario 200 involves a first TRP 205a, a second TRP 205b, and a UE 215. In some aspects, one or both of the TRPs 205 may be one or more of the BSs 105 of the network 100. In other aspects, one or both of the TRPs 205 may be another type of wireless node or wireless communication device configured for communication with one or more UEs in a network. In some aspects, the UE 215 may be one of the UEs 115 of the network 100. For simplicity, FIG. 2 illustrates one UE 215 and two TRPs 205, but a greater number of UEs 215 (e.g., about 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) and/or TRPs 205 (e.g., the about 2, 3, 4 or more) may be supported. In the scenario 200, the TRPs 205 and the UE 215 communicate with each other over at least one radio frequency band. For example, the TRPs 205 may be configured to communicate with the UE 215 on one or more cells corresponding to one or more frequency bands. In some aspects, each of the one or more cells corresponds to a component carrier (CC) . In other aspects, each of the one or more cells corresponds to a bandwidth part (BWP) . The one or more cells may include a primary cell (PCell) or special cell (SpCell) .

In some aspects, one or both of the TRPs 205 may be capable of generating a number of directional transmission beams in a number of beam or spatial directions (e.g., about 2, 4, 8, 16, 32, 64 or more) and may select a certain transmission beam or beam direction to communicate with the UE 215 based on the location of the UE 215 in relation to the location of the TRPs 205 and/or any other environmental factors such as reflectors and/or scatterers in the surrounding. For example, the second TRP 205b may select a transmission beam that provides a best quality (e.g., with the highest receive signal strength) for transmission to the UE 215. The TRP 205b may also select a reception beam that provides a best quality (e.g., with the highest receive signal strength) for reception from the UE 215. As illustrated in FIG. 2, the TRP 205b may generate three

beams

204a, 204b, and 204c. The TRP 205b may determine that it may utilize the beam 204b or the beam 204c to communicate with the UE 215, for example, based on a beam discovery or beam selection procedure.

As explained above, one or both of the TRPs 205 may schedule the UE 215 for an UL communication or a DL communication over a frequency band. For the purposes of the present disclosure, a frequency band may include a component carrier (CC) and/or a bandwidth part (BWP) , for example. In single-DCI mTRP communications, a DCI from one of the TRPs (e.g., TRP 205a) may schedule communications for the first TRP 205a and the second TRP 205b. In multi-DCI (mDCI) mTRP communications, each TRP 205 may transmit DCI to the UE 215 to schedule communications. FIG. 2 may illustrate a mDCI mTRP communication scenario, whereby the first TRP 205a schedules DL and/or UL communications with the UE 215 by a first communication link 207, and the second TRP 205b schedules DL and/or UL communications with the UE 215 by a second communication link 208. In some aspects, a UE 215 may be configured with carrier aggregation to communicate with one or both of the TRPs 205 using one or more serving cells. The serving cells may include, for example, a primary cell (PCell) , one or more secondary cells (SCells) , a PUCCH secondary cell (PSCell) , and/or a special cell (SpCell) . In some aspects, one or more of the serving cells may be configured for mDCI mTRP communications, and one or more cells may be configured for single-TRP communications. A cell may be configured for mDCI mTRP communications if the cell configuration indicates two CORESET pool index values and two timing advance groups (TAGs) . For example, a mDCI cell may indicate two CORESETPoolIndex values and two TAG indicators. A single-TRP cell configuration may indicate a single TAG indicator and/or a single CORESETPoolIndex value.

FIG. 3 illustrates a UL timing advance scheme 250 for the mTRP communication scenario 200 shown in FIG. 2, according to aspects of the present disclosure. As shown in FIG. 3, the first TRP 205a transmits a first DL signal 222, and the second TRP 205b transmits a second DL signal 224. The

signals

222, 224 are shown with respect to a common reference transmit timing 220. It will be understood, however, that the

signals

222, 224 may or may not be transmitted simultaneously. However, the

signals

222, 224 are shown as temporally aligned relative to the transmit reference time 220 to illustrate aspects of UL timing advance in the scheme 250.

The first signal 222 is received by the UE 215 at a first reference time 226, which is associated with a propagation delay T _P1. The propagation delay T _P1 may be based on the physical distance between the first TRP 205a and the UE 215. To provide for time alignment of UL communications to the first TRP 205a, the UE 215 applies a timing advance T _TA1 to a UL communication 232. The timing advance may be associated with the propagation delay T _P1 and a timing advance offset. In some aspects, the timing advance T _TA1 may be based on one or more indicated timing advance parameters of a timing advance command. For example, the timing advance command may be transmitted via a RACH message (e.g., random access response) , via a MAC-CE in DL shared channel communication, and/or by any other suitable communication. The timing advance command may be carried in a timing advance command MAC control element. The element may indicate a timing advance group (TAG) indicator and the timing advance command associated with the TAG indicator. The timing advance command for a TAG may indicate an adjustment of a current timing advance value to a new timing advance value. The adjustment may be indicated by an integer value between 0 and 63, for example. The integer value may be used to determine the timing advance in absolute units of time (e.g., μs) .

The second signal 224 is received by the UE 215 at a second reference time 228, which is associated with a propagation delay T _P2. The propagation delay T _P2 may be based on the physical distance between the second TRP 205b and the UE 215. To provide for time alignment of UL communications to the second TRP 205b, the UE 215 applies a timing advance T _TA2 to a UL communication 234. The timing advance may be associated with the propagation delay T _P2 and a timing advance offset. In some aspects, the timing advance T _TA2 may be based on one or more indicated timing advance parameters of a timing advance command, as similarly explained above with respect to T _TA1.

If the UE 215 is configured to communicate with multiple TRPs 205 on a same serving cell, the serving cell may be configured with multiple TAGs to facilitate different timing advances for communications to each of the TRPs 205a, 205b on the serving cell. In some instances, the UE 215 may also be configured with one or more cells (e.g., SCells) that are configured with a single TAG and a single CORESET pool index. For example a SpCell may be configured with a first CORESET pool associated with a first CORESET pool index and a second CORESET pool associated with a second CORESET pool index. Each CORESET pool may refer to a periodic set of time/frequency resources for which the UE may perform blind decoding operations to attempt to decode DL control information. Accordingly, the UE may monitor for DL control information on the SpCell based on both the first CORESET pool and the second CORESET pool. Another cell configuration, such as an SCell configuration, may indicate only a single CORESET pool associated with a single CORESET pool index for monitoring for the DL configuration.

FIG. 4 is a timing diagram illustrating a transmission frame structure 400 according to some embodiments of the present disclosure. The transmission frame structure 400 may be employed by BSs such as the BSs 105 and UEs such as the UEs 115 in a network such as the network 100 for communications. In particular, the BS may communicate with the UE using time-frequency resources configured as shown in the transmission frame structure 400. In FIG. 4, the x-axes represent time in some arbitrary units and the y-axes represent frequency in some arbitrary units. The transmission frame structure 400 includes a radio frame 402. The duration of the radio frame 402 may vary depending on the embodiments. In an example, the radio frame 402 may have a duration of about ten milliseconds. The radio frame 402 includes M number of subframes 404, where M may be any suitable positive integer. In an example, M may be about 10.

Each subframe 404 may contain N slots 406, where N is any suitable positive number including 1. Each slot 406 includes a number of subcarriers 418 in frequency and a number of symbols 416 in time. The number of subcarriers 418 and/or the number of symbols 416 in a slot 406 may vary depending on the embodiments, for example, based on the channel bandwidth, the subcarrier spacing (SCS) , and/or the cyclic prefix (CP) mode. One subcarrier 418 in frequency and one symbol 416 in time forms one resource element (RE) 420 for transmission.

A BS (e.g., BS 105 in FIG. 1) may schedule a UE (e.g., UE 115 in FIG. 1) for UL and/or DL communications at a time-granularity of slots 406. A BS 105 may schedule a UE 115 to monitor for PDCCH transmissions by instantiating a search space associated with a CORESET 412. The search space may also be instantiated with associated CORESET 414. Thus, as illustrated in the example of FIG. 4, there are two CORESETs, and therefore two monitoring occasions, within the slot 406 that are part of the search space the UE 115 monitors for control information from the BS 105.

While FIG. 4 illustrates two CORESETs, 412 and 414, for purposes of simplicity of illustration and discussion, it will be recognized that embodiments of the present disclosure may scale to many more CORESETs, for example, about 3, 4 or more. Each CORESET may include a set of resources spanning a certain number of subcarriers 418 and a number of symbols 416 (e.g., about 1, 2, or 3) within a slot 406. As an alternative to multiple different CORESETs within a slot 406, one or more of the many CORESETs may be in a different slot than the others. Each CORESET has an associated control channel element (CCE) to resource element group (REG) mapping. A REG may include a group of REs 420. The CCE defines how DL control channel data may be transmitted.

A BS 105 may configure a UE 115 with one or more search spaces by associating a CORESET 412 with a starting position (e.g., a starting slot 406) , a symbol 416 location within a slot 406, a periodicity or a time pattern, and candidate mapping rules. For examples, a search space may include a set of candidates mapped to CCEs with aggregation levels of 1, 4, 4, 8, and/or 12 CCEs. As an example, a search space may include the CORESET 412 starting at the first symbol 416 indexed within a starting slot 406. The search space may also include the CORESET 414 starting at a later symbol index within the starting slot 406. The exemplary search space may have a periodicity of about five slots and may have candidates at aggregation levels of 1, 4, 4, and/or 8.

The UE 115 may perform blind decoding in the search spaces to search for DL control information (e.g., slot format information and/or scheduling information) from the BS. In some examples, the UE may search a subset of the search spaces based on certain rules, for example, associated with the UE’s channel estimation and/or blind decoding capabilities. One such example of DL control information the UE 115 may be blind decoding for is a PDCCH from the BS 105.

As shown in FIG. 4, CORESET 412 and CORESET 414 may be at different frequencies from each other. The CORESETs can be non-contiguous as shown, or they may be contiguous. The frequency ranges of CORESET 412 and CORESET 414 may overlap or not (e.g., as illustrated in FIG. 4, the frequency ranges partially overlap, and therefore are different from each other) . In some aspects, the frequency offset between the CORESETs is a multiple of six RBs, or some other offset. According to the example of FIG. 4, each of CORESET 412 and CORESET 414 may carry a different PDCCH transmission (or none at all, though part of the search space for the UE 115) . CORESET 412 and CORESET 414 can have other characteristics which are different from each other than just frequency (or instead of frequency) . For example, they can differ in CCE-to-REG mapping and/or REG bundling. Or, they can also be associated with different TCI states, thereby being associated with different beams. In addition, the CCE index of a PDCCH monitoring occasion may be different across CORESETs as is discussed in more detail with respect to FIG. 12. Other forms of diversity between CORESETs could be achieved as well, including some combination of differing characteristics (such as all of the above differences together or a subset thereof) .

By adding diversity between the CORESETs, problems with transmission channels associated with those features may be mitigated. FIG. 4 shows two different CORESETs, but there may be more than two CORESETs, each with either the same or different characteristics in any combination.

When a cell is configured for mDCI mTRP communications, UL signals on the cell may be transmitted to one of multiple TRPs. For example, the mDCI mTRP cell may be configured with multiple TAGs to allow for different timing advance commands to be applied to communications for either TRP. Further, the UE may be configured with other cells that are configured with a one or more TAG indicators and one or more CORESET pool indexes. However, not all cells may be configured with the same combinations of TAG indicators or CORESET pool index configurations. Further, not all serving cells may be configured for mDCI mTRP communications. In some aspects, two serving cells may be configured with at least one common CORESET pool index, but may have different TAG configurations. It may be desirable to provide intra-cell and inter-cell association rules for cell configurations such that the wireless communication devices can determine and apply a suitable timing advance for UL communications in an mDCI mTRP communication scenario.

FIG. 5 is a signaling diagram illustrating a mTRP communication method 500 according to some aspects of the present disclosure. The method 500 is employed by a first TRP (TRP1) , a second TRP (TRP2) , and a UE 515. In some aspects, one or both of the TRPs may be one of the BSs 105 in the network 100. In other aspects, one or both of the TRPs 501, 503 may be another type of wireless node or connection point. In some aspects, the UE 515 may be one of the UEs 115 of the network 100. The UE 515 may be configured for mTRP communications with both TRP1 and TRP2. However, it will be understood that the UE 515 may be configured for mTRP communications with more than two TRPs, including three, four, five, six, and/or any other suitable number of TRPs. Further, the UE 515 may be configured for carrier aggregation (CA) using a plurality of serving cells to communicate with the network. In some aspects, the UE 515 may be configured to communicate with both TRPs on a first cell, but not a second cell. In other aspects, the UE 515 may be configured for mTRP communications with TRP1 and TRP2 using two or more cells.

As explained above, the UE 515 may be configured for single-DCI mTRP communications, or multi-DCI (mDCI) mTRP communications. In mDCI mTRP communications, the UE 515 may receive scheduling DCI from either of TRP1 or TRP2 for DL and/or UL communications communicated with the corresponding TRP. Accordingly, TRP1 may transmit DCI to the UE 515 to schedule communications for TRP1, and TRP2 may transmit DCI to the UE 515 to schedule communications for TRP2. In some aspects, the method 500 may be performed in a mDCI mTRP communication scenario. In some aspects, the method 500 involves the UE selecting a reference cell and determining a reference timing for UL communications in the mTRP scenario. In this regard, the UE 515 may be scheduled to transmit UL communications to one of multiple TRPs on one of a plurality of cells. However, some of the cells may not be configured for mDCI mTRP. For example, at least one of the cells may not be configured with two CORESET pool index values and two TAGs, while another cell is configured with two CORESET pool index values and two TAGs. To determine a timing advance appropriate for the receiving TRP for a UL communication on a cell, the UE first selects at least one reference cell, and determines at least one reference timing based on the at least one reference cell.

At action 502, TRP1 transmits, and the UE 515 receives, one or more timing advance (TA) association configurations. In some aspects, action 502 includes TRP1 transmitting a RRC information element (IE) , a MAC IE, and/or a MAC control element (CE) indicating the TA association configuration. In some aspects, the one or more TA association configurations may indicate one or more associations of one or more TAGs or TAG indicators and one or more CORESET pool indexes. Further, each of the one or more TA association may be associated with a serving cell. For example, each TA association configuration may include or indicate, for a corresponding serving cell, at least one CORESET pool index value and at least one TAG indicator associated with the CORESET pool index value. For example, Action 502 may include receiving one or more cell configurations indicating the one or more TA association configurations. In some aspects, the TA association configuration may include an associated TAG field of a CORESET configuration. The associated TAG field may indicate the TAG ID associated with a CORESET pool indicated in the CORESET configuration. In one aspect, action 502 may include communicating, for at least one cell, a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a first CORESETPoolIndex value and a second CORESETPoolIndex value.

As indicated by the dashed line, action 502 may be an optional or alternate aspect of the method 500. For example, in some aspects, the one or more TA association configurations may be fixed or hardcoded configurations, and the method 500 may not include the UE 515 receiving the one or more TA association configurations. In some aspects, the method 500 may include obtaining the one or more TA association configurations from a memory, for example. In some aspects, each fixed TA association configuration may indicate a fixed association between TAG indicator values and CORESET pool index values. For example, the one or more TA association configurations may include a lookup table of CORESET pool index values and/or TAG indicator values, and a corresponding TAG indicator value and/or CORESET pool index value in each row. In other aspects, the one or more fixed TA association configuration configurations may include or indicate a rule for associating TAG indexes and CORESET pool index values. For example, the fixed rule may indicate, for one or more of the serving cells, that a lower of two TAG indicator values is associated with CORESETPoolIndex 0, and the higher of the two TAG indicator values is associated with CORESETPoolIndex 1. In another aspect, the fixed rule may indicate, for one or more of the serving cells, that a higher of two TAG indicator values is associated with CORESETPoolIndex 0, and the lower of the two TAG indicator values is associated with CORESETPoolIndex 1. In another aspect, the fixed rule may indicate that a pTAG will be associated with CORESETPoolIndex 0, or with CORESETPoolIndex 1. In another aspect, the fixed rule may indicate that a first set of TAG indicators (e.g., 1-2) is associated with CORESETPoolIndex 0, and that a second set of TAG indicators (e.g., 3-4) is associated with CORESETPoolIndex 1. It will be understood that these options are exemplary and that other variations and fixed rules are also contemplated by the present disclosure.

The TA association configurations, whether they are indicated semi-statically, or are fixed configurations, may be based on one or more rules. For example, the TA association configuration may include or indicate a plurality of associations for a plurality of serving cells. In some aspects, more than one of the serving cells may be associated with a same TAG indicator value. Further, two or more of the serving cells may be configured with two CORESET pool indicator values. When more than one TRP is communicating with the UE, it may be desirable to establish rule-based configurations so that the UE can apply a suitable TA when communicating on mDCI cells. The present disclosure describes methods and mechanisms for configuring and indicating TAG associations for mDCI mTRP communication scenarios with multiple serving cells. In this regard, FIGS. 6A –8B illustrate different schemes for configuring associations between TAG and CORESET pool. In FIGS. 6A –8B, the UE 515 may be configured with a first cell and a second cell. Each cell is associated with a component carrier (CC) . Accordingly, the first cell may be referred to as CC1, and the second cell may be referred to as CC2. In the illustrated examples, the first cell is configured with two CORESETPoolIndex values (0 and 1) and two TAG indicator values. The second cell may be configured with a single CORESETPoolIndex value and a single associated TAG indicator. FIGS. 6A, 7A, and 8A are flow diagrams illustrating the application of a TA association rule or configuration. FIGS. 6B, 7B, and 8B illustrate a plurality of examples of allowed and prohibited cell configuration combinations according to the corresponding TA association rule.

Referring to FIGS. 5 and 6A, the UE 515 may be configured with a first serving cell (CC1) and a second serving cell (CC2) . Both of CC1 and CC2 may be configured with

CORESETPoolIndex values

0 and 1. According to the scheme 600, if CC1 and CC2 are each configured with a pair of TAGs, then the two pairs of TAGs are either the same or different. Thus, the configurations of CC1 602 and CC2 604 may be provided by determining whether the CC2 TAG associations are identical to the CC1 TAG associations. For example, if CC1 is configured with a first association of CORESETPoolIndex 0 and TAG1, and a second association of CORESETPoolIndex 1 and TAG2, action 606 may include determining whether the CC2 configuration also includes the first association of CORESETPoolIndex 0 and TAG1, and the second association of CORESETPoolIndex 1 and TAG2. This is shown by the top configuration of FIG. 6B. The check mark indicates that these cell configurations are allowed based on the TA association rule or configuration.

If the TAG associations of CC1 and CC2 are not identical, the CC1 and CC2 configurations may be allowed if the one or more TAG indicators for CC2 are completely different from the two TAG indicators for CC1, as indicated by action 608. This is shown by the middle configuration in FIG. 6B, which indicates that the configuration for CC2 includes TAG3 and TAG4, which are each different from either of the TAGs configured for CC1.

If the TAG associations of CC1 and CC2 are not identical, and the one or more TAG indicators for CC2 are not completely different from the two TAG indicators for CC1, then the CC1 and CC2 configurations may not be allowed in accordance with the TA association rule. This is illustrated as the bottom example of FIG. 6B, which shows that CC1 and CC2 have one common association (CORESETPoolIndex 1 and TAG2) , and one different association (CORESETPoolIndex 0 and TAG2 vs. TAG3) . Accordingly, the bottom configuration is not allowed, as indicated by the X mark.

A second TA association scheme 700 is illustrated in FIGS. 7A and 7B. The UE 515 may be configured with a first serving cell (CC1) and a second serving cell (CC2) . CC1 may be configured with

CORESETPoolIndex values

0 and 1, and CC2 may be configured only with CORESETPoolIndex value 0. Accordingly, CC2 may not be configured for mDCI mTRP. According to the scheme 700, the configurations of CC1 702 and CC2 704 may be allowed if the CC2 TAG association is identical to one of the CC1 TAG associations. For example, if CC1 is configured with a first association of CORESETPoolIndex 0 and TAG1, and a second association of CORESETPoolIndex 1 and TAG2, action 706 may include determining whether the CC2 configuration also includes one of the first association of CORESETPoolIndex 0 and TAG1, or the second association of CORESETPoolIndex 1 and TAG2. This is shown by the top configuration and middle configurations of FIG. 7B. The check marks indicate that these cell configurations are allowed based on the TA association rule or configuration of the scheme 700.

If the TAG association of CC2 is not the same as one of the associations of CC1 and CC2, the CC1 and CC2 configurations may be allowed if the TAG indicator for CC2 is different from each of the two TAG indicators for CC1, as indicated by action 708. This is shown by the bottom configuration in FIG. 7B, which indicates that the configuration for CC2 includes TAG3, which is different from either of the TAGs configured for CC1. If the TAG associations of CC1 and CC2 are not identical, and the TAG indicator for CC2 is not different from the two TAG indicators for CC1, then the CC1 and CC2 configurations may not be allowed in accordance with the TA association rule.

Referring to FIGS. 5 and 8A, according to the scheme 800, the configurations of CC1 802 and CC2 804 may be allowed by determining whether any TAG indicators common to the CC1 and CC2 configurations are associated with a same CORESETPoolIndex. If both CC1 and CC2 are configured with

CORESETPoolIndex values

0 and 1 and each of CC1 and CC2 is configured with a pair of TAGs, the two pairs of TAGs can be partially different. In other words, CC1 and CC2 can share one TAG. For example, if CC1 is configured with a first association of CORESETPoolIndex 0 and TAG1, and a second association of CORESETPoolIndex 1 and TAG2, action 806 may include determining whether a common TAG of CC2 (TAG1) is associated with the same CORESETPoolIndex value as CC1. This is shown by the top configuration of FIG. 8B, in which the only common TAG, TAG1, is associated with CORESETPoolIndex 0 in both the CC1 configuration and the CC2 configuration.

If any TAG indicators common to the CC1 and CC2 configurations are associated with a different CORESETPoolIndex in CC1 compared to CC2, the CC1 and CC2 configurations are not allowed. This is shown by the bottom configuration in FIG. 8B, which indicates that both the CC1 and CC2 configurations include TAG, and that TAG2 is associated with CORESETPoolIndex 0 for CC1, and TAG2 is associated with CORESETPoolIndex 1 for CC2.

At action 504, TRP1 transmits, and the UE 515 receives, serving cell configurations for the one or more serving cells including one or more DL control channel configurations associated with the one or more serving cells and TAG configurations associated with the one or more serving cells. In some aspects, each of the serving cells may be associated with a frequency band, such as a component carrier (CC) and/or a bandwidth part (BWP) . The UE 515 may be configured for carrier aggregation (CA) , by which the UE 515 can communicate with TRP1 and TRP2 using two or more serving cells. The serving cells may include, for example, a primary cell (PCell) , one or more secondary cells (SCells) , a PUCCH secondary cell (PSCell) , and/or a special cell (SpCell) . In some aspects, action 504 includes receiving a DL control channel configuration for each cell of the two or more cells. In some aspects, the UE 515 receives a DL control channel configuration and TAG configuration for the at least of the plurality of cells, where the DL control channel configuration indicates, for the at least one cell, two CORESET pool index values, and the TAG configuration indicates, for the at least one cell, two TAG indicators. In some aspects, the DL control channel configuration and the TAG configuration may indicate a first CORESET pool index value and a first TAG indicator, and a second CORESET pool index value and a second TAG indicator. In some aspects, action 504 includes receiving one or more CORESET pool index values and/or TAG indicators for each other serving cell on which the UE is configured to communicate.

Each TAG indicator may be associated with a TA configuration received from one of the TRPs. For example, the method 500 may further include the UE 515 receiving a TA configuration, which may be communicated in a random access message (e.g., random access response, MSG2, MSGB) , and/or in a media access control control element (MAC-CE) . The TA configuration may indicate a TAG indicator value, and a TA command associated with that TAG indicator value. The UE 515 may apply the TA command to all communications associated with the indicated TAG.

In some aspects, action 504 includes receiving one or more radio resource control (RRC) information elements (IEs) indicating one or more DL control channel configurations and one or more TAG configurations. In some aspects, action 504 includes communicating a first cell configuration and a second cell configuration. Communicating the cell configurations may include communicating, for each configured serving cell, a ServingCellConfig RRC IE indicating the TAG indicators associated with the cell. In another aspect, action 504 may include communicating, for at least one cell, a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a first CORESETPoolIndex value and a second CORESETPoolIndex value. In some aspects, the first CORESETPoolIndex value may be 0 or 1, and the second CORESETPoolIndex value may be 0 or 1. As explained above, action 502 may also include receiving, for at least one cell, a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE. In this regard, if action 502 is performed in the method 500, aspects of both actions 502 and 504 may be performed by communicating between at least one of the TRPs 505 and the UE 515, one or more PDCCH-Config RRC IEs and/or ControlResourceSet RRC IEs. For example, a ControlResourceSet RRC IE may indicate, for a serving cell, a CORESET pool index value and an associated TAG ID for the CORESET pool index. In other aspects, such as when the TA association configuration is hardcoded, the PDCCH-Config RRC IEs and/or ControlResourceSet RRC IEs may not indicate an associated TAG ID for a CORESET pool index.

As explained above, in some aspects, the method 500 may be employed in a mTRP communication scenario in which the UE 515 receives the plurality of TAG indicators from one or more TRPs over one or more serving cells. Although shown as being received from TRP1 only in FIG. 5, it will be understood that action 504 may include receiving DL control channel configurations from different TRPs, such as from TRP1 and from TRP2. For example, a first DL control channel configuration for a first cell may be transmitted by TRP1, and a second DL control channel configuration for a second cell may be transmitted by TRP2.

At action 506, TRP1 transmits, and the UE 515 receives, a DL signal. In some aspects, receiving the DL signal may include receiving a DL shared channel transmission, a DL control channel transmission, a reference signal, a synchronization signal block (SSB) , and or any other suitable type of DL signal. For example, action 506 may include TRP1 transmitting, on the first cell, a PDSCH transmission carrying DL data. In other aspects, action 506 may include TRP1 transmitting, on a first cell, a DCI scheduling a UL communication. The DL signal may correspond to a DL timing. For example, the DL signal may include DCI scheduling a UL communication based on the DL timing as received by the UE 515. Accordingly, the DL signal may be received by the UE 515 following a propagation delay associated with the distance between the UE 515 and TRP1.

At action 508, to compensate for the propagation delay and to facilitate suitable orthogonality of UL communications received at TRP1, the UE 515 determines a timing advance based on a first TA configuration for a first TAG indicator. In some aspects, action 508 includes determining a reference cell and reference timing to determine the TA for the UL communications. In some aspects, the UE 515 may determine or select the first TAG indicator based on the TA association configuration. The TA association configuration may be based on a rule or configuration scheme, such as the schemes 600-800 illustrated in FIGS. 6A –8B. In some aspects, the TA association configuration may be indicated in a DL control channel monitoring configuration, as explained above. In other aspects, the TA association configuration may be fixed. Accordingly, the UE 515 may obtain or determine the first TAG based on a fixed TA association stored in a memory. The UE 515 may then apply a timing advance based on the associated TAG indicator.

At action 510, the UE 515 transmits, and TRP1 receives, a UL communication based on the timing advance determined at action 510. The UL communication may be transmitted on the same cell on which the DL signal was transmitted in action 506, or a different cell. The timing advance applied to the UL communication may cause the UL communication to be received based on the timing of TRP1 for orthogonality of UL communications with other UEs. In some aspects, action 510 includes transmitting UL control information, UL data, and/or UL reference signals. For example, action 512 may include transmitting, to TRP1, UCI, UL data in a PUSCH, SRS, and/or any other suitable type of UL communication. In some aspects, transmitting the UL communication is based on a UL scheduling grant. For example, the DL signal transmitted at action 506 may include DCI indicating a scheduling grant for the UL communication. In some aspects, the UL scheduling grant may be based on a scheduling request transmitted by the UE 515. For example, the scheduling request may be transmitted as part of a RACH procedure (e.g., RACH MSG3) . In another example, the scheduling request may be transmitted in a PUCCH.

At action 512, TRP2 transmits, and the UE 515 receives, a second DL signal on a second cell (cell 2) . In some aspects, TRP2 may be in a different physical/geographical location than TRP1. Accordingly, the propagation delay, and therefore the timing advance, between the UE 515 and TRP2 may be different than the propagation delay /timing advance between the UE 515 and TRP1. Although the first DL signal in FIG. 5 is associated with cell 1 and the second DL signal is associated with cell 2, it will be understood that TRP1 and TRP2 may be configured to communicate respective DL signals using a same cell. For example, TRP2 may be configured to communicate with the UE 515 on one or more cells, component carriers, and/or bandwidth parts (BWPs) that are also configured for communication between the UE 515 and TRP1. In some aspects, receiving the second DL signal may include receiving a DL shared channel transmission, a DL control channel transmission, a reference signal, a synchronization signal block (SSB) , and or any other suitable type of DL signal. For example, action 512 may include TRP2 transmitting, on the second cell, a PDSCH transmission carrying DL data. In other aspects, action 512 may include TRP2 transmitting, on the second cell, a DCI scheduling a UL communication. The second DL signal may correspond to a DL timing. For example, the second DL signal may include DCI scheduling a UL communication based on the DL timing as received by the UE 515. Accordingly, the second DL signal may be received by the UE 515 following a propagation delay associated with the distance between the UE 515 and TRP2.

At action 514, to compensate for the propagation delay and to facilitate suitable orthogonality of UL communications received at TRP2, the UE 515 determines a timing advance based on a TA configuration for a TAG indicator associated with TRP2, and a DL reference timing determined based on the received DL signal. In some aspects, action 508 includes determining a reference cell and reference timing to determine the TA for the UL communications. In some aspects, the UE 515 may determine or select a second TAG indicator based on the TA association configuration. The TA association configuration may be based on a rule or configuration scheme, such as the

schemes

600, 700, and 800 illustrated in FIGS. 6A –8B. In some aspects, the TA association configuration may be indicated in a DL control channel monitoring configuration, as explained above. In other aspects, the TA association configuration may be fixed. Accordingly, the UE 515 may obtain or determine the second TAG based on a fixed TA association stored in a memory. The UE 515 may then apply a timing advance based on the associated TAG indicator.

At action 516, the UE 515 transmits, and TRP2 receives, a second UL communication based on the reference timing determined at action 518. In some aspects, the timing advance applied to the second UL communication may cause the UL communication to be received based on the timing of TRP2 for orthogonality of UL communications with other UEs. In some aspects, action 516 includes transmitting UL control information, UL data, and/or UL reference signals. For example, action 516 may include transmitting, to TRP2, UCI, UL data in a PUSCH, SRS, and/or any other suitable type of UL communication.

FIG. 9 is a block diagram of an exemplary BS 900 according to some aspects of the present disclosure. The BS 900 may be a BS 105 as discussed in FIG. 1, and or a TRP as discussed in FIGS. 2-3 and 5. For example, the BS 900 may be configured as one of multiple TRPs in a network configured for communication with at least one UE, such as one of the

UEs

115, 215, 515, and/or 1000. As shown, the BS 900 may include a processor 902, a memory 904, a timing advance module 908, a transceiver 910 including a modem subsystem 912 and a RF unit 914, and one or more antennas 916. These elements may be coupled with one another. The term “coupled” may refer to directly or indirectly coupled or connected to one or more intervening elements. For instance, these elements may be in direct or indirect communication with each other, for example via one or more buses.

The processor 902 may have various features as a specific-type processor. For example, these may include a CPU, a DSP, an ASIC, a controller, a FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 902 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 memory 904 may include a cache memory (e.g., a cache memory of the processor 902) , RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, a solid state memory device, one or more hard disk drives, memristor-based arrays, other forms of volatile and non-volatile memory, or a combination of different types of memory. In some aspects, the memory 904 may include a non-transitory computer-readable medium. The memory 904 may store instructions 906. The instructions 906 may include instructions that, when executed by the processor 902, cause the processor 902 to perform operations described herein, for example, aspects of FIGS. 3, 5-8B and 11. Instructions 906 may also be referred to as program code. The program code may be for causing a wireless communication device to perform these operations, for example by causing one or more processors (such as processor 902) to control or command the wireless communication device to do so. The terms “instructions” and “code” should be interpreted broadly to include any type of computer-readable statement (s) . For example, the terms “instructions” and “code” may refer to one or more programs, routines, sub-routines, functions, procedures, etc. “Instructions” and “code” may include a single computer-readable statement or many computer-readable statements.

The timing advance module 908 may be implemented via hardware, software, or combinations thereof. For example, the timing advance module 908 may be implemented as a processor, circuit, and/or instructions 906 stored in the memory 904 and executed by the processor 902. In some examples, the timing advance module 908 can be integrated within the modem subsystem 912. For example, the timing advance module 908 can be implemented by a combination of software components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry) within the modem subsystem 912. The timing advance module 908 may communicate with one or more components of BS 900 to implement various aspects of the present disclosure, for example, aspects of FIGS. 3, 5-8B, and 11.

In some aspects, the timing advance module 908 is configured to transmit, to a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator. The second wireless communication device may be a user equipment (UE) . For example, the BS 900 may be one TRP of a plurality of TRPs configured to communicate with the UE on at least one cell. The first TAG indicator may be associated with a first CORESET pool index value by a first association. The second TAG indicator may be associated with a second CORESET pool index value by a second association. In some aspects, transmitting the first cell configuration may include transmitting a radio resource control (RRC) configuration, a media access control (MAC) information element (IE) , a MAC control element (CE) , and/or any other suitable type of communication or message indicating the first cell configuration. For example, transmitting the first cell configuration may include transmitting a ServingCellConfig RRC IE indicating the first TAG indicator and the second TAG indicator.

In some aspects, the first cell may be one of multiple serving cells configured for communications between the timing advance module 908 and the second wireless communication device. In this regard, the timing advance module 908 may be configured for carrier aggregation (CA) to communicate using a plurality of serving cells, which may include a special cell (SpCell) , a primary cell (Pcell) , a secondary cell (Scell) , a PUCCH secondary cell (PSCell) , and/or any other suitable type of cell. As explained above, the first cell may correspond to a component carrier (CC) , bandwidth part (BWP) , and/or any other suitable set of frequency domain resources.

The first association and the second association may be configured by a semi-static configuration (e.g., RRC signaling, MAC physical data unit (PDU) ) , and/or may be fixed configurations hardcoded in at least one of the BS 900 (e.g., the memory 904) or a second wireless communication device.

In some aspects, the first cell may be configured for multiple DCI (mDCI) -based mTRP communications if the first cell is configured with two CORESET pool index values. In this regard, the first cell configuration may include or indicate one or more DL control channel monitoring configurations indicating the first CORESET pool index value and the second CORESET pool index value. For example, the timing advance module 908 may be configured to transmit multiple semi-static configurations or information elements indicating the TAG indicators and the CORESET pool index values. In one example, the timing advance module 908 may be configured to transmit a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a first CORESETPoolIndex value and a second CORESETPoolIndex value. In some aspects, the first CORESETPoolIndex value may be 0 or 1, and the second CORESETPoolIndex value may be 0 or 1. In some aspects, the timing advance module 908 may be configured to transmit a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the timing advance module 908 and/or the second wireless communication device may assume that the CORESET pool index value for the first cell is 0.

In some aspects, the timing advance module 908 is configured to transmit, to the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator. In some aspects, the third TAG indicator is associated with a third CORESET pool index value by a third association. In some aspects, the second cell corresponds to a different CC, BWP, or other frequency domain resource that is different from the first cell. As above, transmitting the second cell configuration may include transmitting a RRC configuration, a MAC IE, a MAC CE, and/or any other suitable type of communication or message indicating the second cell configuration. For example, transmitting the second cell configuration may include transmitting a ServingCellConfig RRC IE indicating the third TAG indicator. In another aspect, transmitting the second cell configuration may include transmitting multiple semi-static configurations or information elements indicating the third TAG indicator and the third CORESET pool index value. In one example, the timing advance module 908 device may be configured to transmit a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a third CORESETPoolIndex value. In some aspects, the third CORESETPoolIndex value may be 0 or 1. In some aspects, the timing advance module 908 may communicate a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the timing advance module 908 and/or the second wireless communication device may assume that the CORESET pool index value for the second cell is 0.

In another aspect, the first association, the second association, and the third association may be based on one or more timing advance (TA) association configurations. The one or more TA association configurations may be semi-static configurations indicated by RRC signaling, MAC signaling, or any other suitable type of signaling. In another aspect, the TA association configurations may be fixed configurations hardcoded in at least one of the UE 1000 (e.g., memory 904) and/or the second wireless communication device. In one example, the timing advance module 908 is configured to transmit, to the second wireless communication device, one or more DL control channel monitoring configurations indicating at least one of the first association, the second association, and/or the third association. For example, a DL control channel monitoring configuration may include a ControlResourceSet configuration. The ControlResourceSet configuration may include or indicate at least one associated TAG Id field for at least one configured CORESET pool index associated with the ControlResourceSet configuration. In some aspects, each DL control channel monitoring configuration or CORESET configuration may indicate a single CORESET pool index value and a single associated TAG Id for the single COREST pool index value. In another example, at least one of the CORESET configurations may include or indicate two CORESET pool index values and two associated TAG Ids.

In some aspects, the timing advance module 908 may be configured to perform one or more aspects of the method 500 and the schemes shown in FIGS. 6A –8B.

As shown, the transceiver 910 may include the modem subsystem 912 and the RF unit 914. The transceiver 910 can be configured to communicate bi-directionally with other devices, such as the UEs 115 and/or BS 900 and/or another core network element. The modem subsystem 912 may be configured to modulate and/or encode data according to a MCS, e.g., a LDPC coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc. The RF unit 914 may be configured to process (e.g., perform analog to digital conversion or digital to analog conversion, etc. ) modulated/encoded data (e.g., RRC table (s) for channel access configurations, scheduling grants, channel access configuration activation, RRC configurations, PDSCH data, PDCCH DCI, etc. ) from the modem subsystem 912 (on outbound transmissions) or of transmissions originating from another source such as a UE 115, 215, and/or UE 1000. The RF unit 914 may be further configured to perform analog beamforming in conjunction with the digital beamforming. Although shown as integrated together in transceiver 910, the modem subsystem 912 and/or the RF unit 914 may be separate devices that are coupled together at the BS 900 to enable the BS 900 to communicate with other devices.

The RF unit 914 may provide the modulated and/or processed data, e.g. data packets (or, more generally, data messages that may contain one or more data packets and other information) , to the antennas 916 for transmission to one or more other devices. The antennas 916 may further receive data messages transmitted from other devices and provide the received data messages for processing and/or demodulation at the transceiver 910. The transceiver 910 may provide the demodulated and decoded data (e.g., channel sensing reports, PUCCH UCI, PUSCH data, etc. ) to the timing advance module 908 for processing. The antennas 916 may include multiple antennas of similar or different designs in order to sustain multiple transmission links.

In an aspect, the BS 900 can include multiple transceivers 910 implementing different RATs (e.g., NR and LTE) . In an aspect, the BS 900 can include a single transceiver 910 implementing multiple RATs (e.g., NR and LTE) . In an aspect, the transceiver 910 can include various components, where different combinations of components can implement different RATs.

Further, in some aspects, the processor 902 is coupled to the memory 904 and the transceiver 910. The processor 902 is configured to communicate, with a second wireless communication device via the transceiver 910, a plurality of channel access configurations. The processor 902 is further configured to communicate, with the second wireless communication device via the transceiver 910, a scheduling grant for communicating a communication signal in an unlicensed band, where the scheduling grant includes an indication of a first channel access configuration of the plurality of channel access configurations. The processor 902 is further configured to communicate, with the second wireless communication device in the unlicensed band via the transceiver 910 based on the first channel access configuration, the communication signal.

FIG. 10 is a block diagram of an exemplary UE 1000 according to some aspects of the present disclosure. The UE 1000 may be a UE 115 as discussed in FIG. 1 or a UE 215 as discussed in FIG. 2, or the UE 515 as discussed in FIG. 5. As shown, the UE 1000 may include a processor 1002, a memory 1004, a timing advance module 1008, a transceiver 1010 including a modem subsystem 1012 and a radio frequency (RF) unit 1014, and one or more antennas 1016. These elements may be coupled with one another. The term “coupled” may refer to directly or indirectly coupled or connected to one or more intervening elements. For instance, these elements may be in direct or indirect communication with each other, for example via one or more buses.

The processor 1002 may include a central processing unit (CPU) , a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 1002 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 memory 1004 may include a cache memory (e.g., a cache memory of the processor 1002) , random access memory (RAM) , magnetoresistive RAM (MRAM) , read-only memory (ROM) , programmable read-only memory (PROM) , erasable programmable read only memory (EPROM) , electrically erasable programmable read only memory (EEPROM) , flash memory, solid state memory device, hard disk drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In an aspect, the memory 1004 includes a non-transitory computer-readable medium. The memory 1004 may store, or have recorded thereon, instructions 1006. The instructions 1006 may include instructions that, when executed by the processor 1002, cause the processor 1002 to perform the operations described herein with reference to a UE 115 or an anchor in connection with aspects of the present disclosure, for example, aspects of FIGS. 3 and 5-8B and 10. Instructions 1006 may also be referred to as code, which may be interpreted broadly to include any type of computer-readable statement (s) as discussed above with respect to FIG. 9.

The timing advance module 1008 may be implemented via hardware, software, or combinations thereof. For example, the timing advance module 1008 may be implemented as a processor, circuit, and/or instructions 1006 stored in the memory 1004 and executed by the processor 1002. In some aspects, the timing advance module 1008 can be integrated within the modem subsystem 1012. For example, the timing advance module 1008 can be implemented by a combination of software components (e.g., executed by a DSP or a general processor) and hardware components (e.g., logic gates and circuitry) within the modem subsystem 1012. The timing advance module 1008 may communicate with one or more components of UE 1000 to implement various aspects of the present disclosure, for example, aspects of FIGS. 3, 5-8B, and 11.

In some aspects, the timing advance module 1008 is configured to receive, from a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator. The second wireless communication device may be a base station (BS) . For example, the BS may be one TRP of a plurality of TRPs configured to communicate with the timing advance module 1008 on at least one cell. The first TAG indicator may be associated with a first CORESET pool index value by a first association. The second TAG indicator may be associated with a second CORESET pool index value by a second association. In some aspects, receiving the first cell configuration may include receiving a radio resource control (RRC) configuration, a media access control (MAC) information element (IE) , a MAC control element (CE) , and/or any other suitable type of communication or message indicating the first cell configuration. For example, receiving the first cell configuration may include receiving a ServingCellConfig RRC IE indicating the first TAG indicator and the second TAG indicator.

In some aspects, the first cell may be one of multiple serving cells configured for communications between the timing advance module 1008 and the second wireless communication device. In this regard, one or both of the timing advance module 1008 and the second wireless communication device may be configured for carrier aggregation (CA) to communicate using a plurality of serving cells, which may include a special cell (SpCell) , a primary cell (Pcell) , a secondary cell (Scell) , a PUCCH secondary cell (PSCell) , and/or any other suitable type of cell. As explained above, the first cell may correspond to a component carrier (CC) , bandwidth part (BWP) , and/or any other suitable set of frequency domain resources.

The first association and the second association may be configured by a semi-static configuration (e.g., RRC signaling, MAC physical data unit (PDU) ) , and/or may be fixed configurations hardcoded in at least one of the UE 1000 (e.g., the memory 1004) or a second wireless communication device.

In some aspects, the first cell may be configured for multiple DCI (mDCI) -based mTRP communications if the first cell is configured with two CORESET pool index values. In this regard, the first cell configuration may include or indicate one or more DL control channel monitoring configurations indicating the first CORESET pool index value and the second CORESET pool index value. For example, the timing advance module 1008 may be configured to receive multiple semi-static configurations or information elements indicating the TAG indicators and the CORESET pool index values. In one example, the timing advance module 1008 may be configured to receive a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a first CORESETPoolIndex value and a second CORESETPoolIndex value. In some aspects, the first CORESETPoolIndex value may be 0 or 1, and the second CORESETPoolIndex value may be 0 or 1. In some aspects, the timing advance module 1008 may be configured to receive a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the timing advance module 1008 and/or the second wireless communication device may assume that the CORESET pool index value for the first cell is 0.

In some aspects, the timing advance module 1008 is configured to receive, from the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator. In some aspects, the third TAG indicator is associated with a third CORESET pool index value by a third association. In some aspects, the second cell corresponds to a different CC, BWP, or other frequency domain resource that is different from the first cell. As above, receiving the second cell configuration may include receiving a RRC configuration, a MAC IE, a MAC CE, and/or any other suitable type of communication or message indicating the second cell configuration. For example, receiving the second cell configuration may include receiving a ServingCellConfig RRC IE indicating the third TAG indicator. In another aspect, receiving the second cell configuration may include receiving multiple semi-static configurations or information elements indicating the third TAG indicator and the third CORESET pool index value. In one example, the timing advance module 1008 device may be configured to receive a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a third CORESETPoolIndex value. In some aspects, the third CORESETPoolIndex value may be 0 or 1. In some aspects, the timing advance module 1008 may communicate a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the timing advance module 1008 and/or the second wireless communication device may assume that the CORESET pool index value for the second cell is 0.

In another aspect, the first association, the second association, and the third association may be based on one or more timing advance (TA) association configurations. The one or more TA association configurations may be semi-static configurations indicated by RRC signaling, MAC signaling, or any other suitable type of signaling. In another aspect, the TA association configurations may be fixed configurations hardcoded in at least one of the UE 1000 (e.g., memory 1004) and/or the second wireless communication device. In one example, the timing advance module 1008 is configured to receive, from the second wireless communication device, one or more DL control channel monitoring configurations indicating at least one of the first association, the second association, and/or the third association. For example, a DL control channel monitoring configuration may include a ControlResourceSet configuration. The ControlResourceSet configuration may include or indicate at least one associated TAG Id field for at least one configured CORESET pool index associated with the ControlResourceSet configuration. In some aspects, each DL control channel monitoring configuration or CORESET configuration may indicate a single CORESET pool index value and a single associated TAG Id for the single COREST pool index value. In another example, at least one of the CORESET configurations may include or indicate two CORESET pool index values and two associated TAG Ids.

In some aspects, the timing advance module 1008 may be configured to perform one or more aspects of the method 500 and the schemes shown in FIGS. 6A –8B.

As shown, the transceiver 1010 may include the modem subsystem 1012 and the RF unit 1014. The transceiver 1010 can be configured to communicate bi-directionally with other devices, such as the BSs 105 and 900. The modem subsystem 1012 may be configured to modulate and/or encode the data from the memory 1004 and/or the timing advance module 1008 according to a modulation and coding scheme (MCS) , e.g., a low-density parity check (LDPC) coding scheme, a turbo coding scheme, a convolutional coding scheme, a digital beamforming scheme, etc. The RF unit 1014 may be configured to process (e.g., perform analog to digital conversion or digital to analog conversion, etc. ) modulated/encoded data (e.g., channel sensing reports, PUCCH UCI, PUSCH data, etc. ) or of transmissions originating from another source such as a UE 115, a BS 105, or an anchor. The RF unit 1014 may be further configured to perform analog beamforming in conjunction with the digital beamforming. Although shown as integrated together in transceiver 1010, the modem subsystem 1012 and the RF unit 1014 may be separate devices that are coupled together at the UE 1000 to enable the UE 1000 to communicate with other devices.

The RF unit 1014 may provide the modulated and/or processed data, e.g. data packets (or, more generally, data messages that may contain one or more data packets and other information) , to the antennas 1016 for transmission to one or more other devices. The antennas 1016 may further receive data messages transmitted from other devices. The antennas 1016 may provide the received data messages for processing and/or demodulation at the transceiver 1010. The transceiver 1010 may provide the demodulated and decoded data (e.g., RRC table (s) for channel access configurations, scheduling grants, channel access configuration activation, timing advance configurations, RRC configurations, PUSCH configurations, SRS resource configurations, PUCCH configurations, BWP configurations, PDSCH data, PDCCH DCI, etc. ) to the timing advance module 1008 for processing. The antennas 1016 may include multiple antennas of similar or different designs in order to sustain multiple transmission links.

In an aspect, the UE 1000 can include multiple transceivers 1010 implementing different RATs (e.g., NR and LTE) . In an aspect, the UE 1000 can include a single transceiver 1010 implementing multiple RATs (e.g., NR and LTE) . In an aspect, the transceiver 1010 can include various components, where different combinations of components can implement different RATs.

Further, in some aspects, the processor 1002 is coupled to the memory 1004 and the transceiver 1010. The processor 1002 is configured to communicate, with a second wireless communication device via the transceiver 1010, one or more timing advance configurations and/or one or more cell configurations. The processor 1002 may be further configured to select one or more reference cells for communication in a mTRP communication scenario, and to determine one or more reference timings and/or one or more timing advances based on the one or more reference cells.

FIG. 11 is a flow diagram illustrating a wireless communication method 1100 according to some aspects of the present disclosure. Aspects of the method 1100 can be executed by a computing device (e.g., a processor, processing circuit, and/or other suitable component) of a wireless communication device or other suitable means for performing the blocks. In one aspect, a UE, such as one of the

UEs

115, 215, 515, and/or 1000, may utilize one or more components, such as the processor 1002, the memory 1004, the timing advance module 1008, the transceiver 1010, the modem 1012, the RF unit 1014, and the one or more antennas 1016, to execute the blocks of method 1100. In another aspect, a BS, such as one of the BSs 105 and/or 1000, may utilize one or more components, such as the processor 1002, the memory 1004, the timing advance module 1008, the transceiver 1010, the modem 1012, the RF unit 1014, and the one or more antennas 1016, to execute the blocks of method 1100. The method 1100 may employ similar mechanisms as described in FIGS. 5-8B. In some aspects, the BS may be configured as one of a plurality of transmission-reception points (TRPs) in a mTRP communication scenario. Accordingly, aspects of the method 1100 may be described with reference to one or more TRPs and one or more UEs. The method 1100 may employ similar mechanisms as described in FIGS. 5-8B. As illustrated, the method 1100 includes a number of enumerated blocks, but aspects of the method 1100 may include additional blocks before, after, and in between the enumerated blocks. In some aspects, one or more of the enumerated blocks may be omitted or performed in a different order.

At block 1110, the first wireless communication device communicates, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator. The first TAG indicator may be associated with a first CORESET pool index value by a first association. The second TAG indicator may be associated with a second CORESET pool index value by a second association. In some aspects, communicating the first cell configuration may include communicating a radio resource control (RRC) configuration, a media access control (MAC) information element (IE) , a MAC control element (CE) , and/or any other suitable type of communication or message indicating the first cell configuration. For example, communicating the first cell configuration may include communicating a ServingCellConfig RRC IE indicating the first TAG indicator and the second TAG indicator.

In some aspects, the first cell may be one of multiple serving cells configured for communications between the first wireless communication device and the second wireless communication device. In this regard, one or both of the first wireless communication device and the second wireless communication device may be configured for carrier aggregation (CA) to communicate using a plurality of serving cells, which may include a special cell (SpCell) , a primary cell (Pcell) , a secondary cell (Scell) , a PUCCH secondary cell (PSCell) , and/or any other suitable type of cell. As explained above, the first cell may correspond to a component carrier (CC) , bandwidth part (BWP) , and/or any other suitable set of frequency domain resources.

The first association and the second association may be configured by a semi-static configuration (e.g., RRC signaling, MAC physical data unit (PDU) ) , and/or may be fixed configurations hardcoded in at least one of the first wireless communication device or a second wireless communication device. The associations between the TAG indicators and the CORESET pool index values will be described in more detail below with respect to block 1120.

In some aspects, the first cell may be configured for multiple DCI (mDCI) -based mTRP communications if the first cell is configured with two CORESET pool index values. In this regard, the first cell configuration may include or indicate one or more DL control channel monitoring configurations indicating the first CORESET pool index value and the second CORESET pool index value. For example, block 1110 may include communicating multiple semi-static configurations or information elements indicating the TAG indicators and the CORESET pool index values. In one example, the first wireless communication device may communicate a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a first CORESETPoolIndex value and a second CORESETPoolIndex value. In some aspects, the first CORESETPoolIndex value may be 0 or 1, and the second CORESETPoolIndex value may be 0 or 1. In some aspects, the first wireless communication device may communicate a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the first wireless communication device and/or the second wireless communication device may assume that the CORESET pool index value for the first cell is 0.

In one aspect, a UE may utilize one or more components, such as the processor 1002, the memory 1004, the timing advance module 1008, the transceiver 1010, the modem 1012, the RF unit 1014, and the one or more antennas 1016, to execute the actions of block 1110. In another aspect, a BS may utilize one or more components, such as the processor 902, the memory 904, the timing advance module 908, the transceiver 910, the modem 912, the RF unit 914, and the one or more antennas 916, to execute the actions of block 1110.

At block 1120, the first wireless communication device communicates, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator. In some aspects, the third TAG indicator is associated with a third CORESET pool index value by a third association. In some aspects, the second cell corresponds to a different CC, BWP, or other frequency domain resource that is different from the first cell. As above, communicating the second cell configuration may include communicating a RRC configuration, a MAC IE, a MAC CE, and/or any other suitable type of communication or message indicating the second cell configuration. For example, communicating the second cell configuration may include communicating a ServingCellConfig RRC IE indicating the third TAG indicator. In another aspect, communicating the second cell configuration may include communicating multiple semi-static configurations or information elements indicating the third TAG indicator and the third CORESET pool index value. In one example, the first wireless communication device may communicate a PDCCH-Config RRC IE and/or a ControlResourceSet RRC IE indicating a third CORESETPoolIndex value. In some aspects, the third CORESETPoolIndex value may be 0 or 1. In some aspects, the first wireless communication device may communicate a DL control channel configuration that does not indicate any CORESET pool index values. In this circumstance, the first wireless communication device and/or the second wireless communication device may assume that the CORESET pool index value for the second cell is 0.

Referring still to block 1120, in another aspect, the first association, the second association, and the third association may be based on one or more timing advance (TA) association configurations. The one or more TA association configurations may be semi-static configurations indicated by RRC signaling, MAC signaling, or any other suitable type of signaling. In another aspect, the TA association configurations may be fixed configurations hardcoded in at least one of the first wireless communication device and/or the second wireless communication device. In one example, the method 1100 may include the first wireless communication device communicating, with the second wireless communication device, one or more DL control channel monitoring configurations indicating at least one of the first association, the second association, and/or the third association. For example, a DL control channel monitoring configuration may include a ControlResourceSet configuration. The ControlResourceSet configuration may include or indicate at least one Associated TAG Id field for at least one configured CORESET pool index associated with the ControlResourceSet configuration. In some aspects, each DL control channel monitoring configuration or CORESET configuration may indicate a single CORESET pool index value and a single associated TAG Id for the single COREST pool index value. In another example, at least one of the CORESET configurations may include or indicate two CORESET pool index values and two associated TAG Ids.

In some aspects, the first association, second association, and third association may be based on the one or more TA association configurations. In some aspects, the one or more TA association configurations may provide that the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

In one aspect, a UE may utilize one or more components, such as the processor 1002, the memory 1004, the timing advance module 1008, the transceiver 1010, the modem 1012, the RF unit 1014, and the one or more antennas 1016, to execute the actions of block 1120. In another aspect, a BS may utilize one or more components, such as the processor 902, the memory 904, the timing advance module 908, the transceiver 910, the modem 912, the RF unit 914, and the one or more antennas 916, to execute the actions of block 1120.

In some aspects, the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association. In some aspects, the third association is the same as the first association and the fourth association is the same as the second association; or each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator. In another aspect, the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and the third association is the same as one of the first association or the second association. In another aspect, the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator. In another aspect, the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association. In some aspects, the third association is the same as one of the first association or the second association; and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.

In some aspects, the method 1100 further includes communicating a radio resource control configuration comprising the one or more TA association configurations, the one or more TA association configurations indicating the first association, the second association, and the third association. In some aspects, the first wireless communication device comprises a base station (BS) and the second wireless communication device comprises a user equipment (UE) . In this regard, the communicating the first cell configuration may include transmitting, by the BS to the UE, the first cell configuration; and the communicating the second cell configuration may include transmitting, by the BS to the UE, the second cell configuration. In another aspect, the first wireless communication device comprises a user equipment (UE) and the second wireless communication device comprises a base station (BS) . In this regard, the communicating the first cell configuration may include receiving, by the UE from the BS, the first cell configuration; and the communicating the second cell configuration may include receiving, by the UE from the BS, the second cell configuration.

The method 1100 may include one or more steps, actions, or other aspects illustrated in FIGS. 3 and 5-8B and described above.

FIG. 12 shows a diagram illustrating an example disaggregated base station 1200 architecture. The disaggregated base station 1200 architecture may include one or more central units (CUs) 1210 that can communicate directly with a core network 1220 via a backhaul link, or indirectly with the core network 1220 through one or more disaggregated base station units (such as a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC) 1225 via an E2 link, or a Non-Real Time (Non-RT) RIC 1215 associated with a Service Management and Orchestration (SMO) Framework 1205, or both) . A CU 1210 may communicate with one or more distributed units (DUs) 1230 via respective midhaul links, such as an F1 interface. The DUs 1230 may communicate with one or more radio units (RUs) 1240 via respective fronthaul links. The RUs 1240 may communicate with respective UEs 120 via one or more radio frequency (RF) access links. In some implementations, the UE 120 may be simultaneously served by multiple RUs 1240.

Each of the units, i.e., the CUs 1210, the DUs 1230, the RUs 1240, as well as the Near-RT RICs 1225, the Non-RT RICs 1215 and the SMO Framework 1205, may include one or more interfaces or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter or transceiver (such as a radio frequency (RF) transceiver) , configured to receive or transmit signals, or both, over a wireless transmission medium to one or more of the other units.

In some aspects, the CU 1210 may host one or more higher layer control functions. Such control functions can include radio resource control (RRC) , packet data convergence protocol (PDCP) , service data adaptation protocol (SDAP) , or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU 1210. The CU 1210 may be configured to handle user plane functionality (i.e., Central Unit –User Plane (CU-UP) ) , control plane functionality (i.e., Central Unit –Control Plane (CU-CP) ) , or a combination thereof. In some implementations, the CU 1210 can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as the E1 interface when implemented in an O-RAN configuration. The CU 1210 can be implemented to communicate with the DU 1230, as necessary, for network control and signaling.

The DU 1230 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 1240. In some aspects, the DU 1230 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, or the like) depending, at least in part, on a functional split, such as those defined by the 3rd Generation Partnership Project (3GPP) . In some aspects, the DU 1230 may further host one or more low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 1230, or with the control functions hosted by the CU 1210.

Lower-layer functionality can be implemented by one or more RUs 1240. In some deployments, an RU 1240, controlled by a DU 1230, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing fast Fourier transform (FFT) , inverse FFT (iFFT) , digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like) , or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU (s) 1240 can be implemented to handle over the air (OTA) communication with one or more UEs 120. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU (s) 1240 can be controlled by the corresponding DU 1230. In some scenarios, this configuration can enable the DU (s) 1230 and the CU 1210 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

The SMO Framework 1205 may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 1205 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements which may be managed via an operations and maintenance interface (such as an O1 interface) . For virtualized network elements, the SMO Framework 1205 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 1290) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface) . Such virtualized network elements can include, but are not limited to, CUs 1210, DUs 1230, RUs 1240 and Near-RT RICs 1225. In some implementations, the SMO Framework 1205 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-eNB) 1211, via an O1 interface. Additionally, in some implementations, the SMO Framework 1205 can communicate directly with one or more RUs 1240 via an O1 interface. The SMO Framework 1205 also may include a Non-RT RIC 1215 configured to support functionality of the SMO Framework 1205.

The Non-RT RIC 1215 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, Artificial Intelligence/Machine Learning (AI/ML) workflows including model training and updates, or policy-based guidance of applications/features in the Near-RT RIC 1225. The Non-RT RIC 1215 may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC 1225. The Near-RT RIC 1225 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 1210, one or more DUs 1230, or both, as well as an O-eNB, with the Near-RT RIC 1225.

In some implementations, to generate AI/ML models to be deployed in the Near-RT RIC 1225, the Non-RT RIC 1215 may receive parameters or e14ternal enrichment information from external servers. Such information may be utilized by the Near-RT RIC 1225 and may be received at the SMO Framework 1205 or the Non-RT RIC 1215 from non-network data sources or from network functions. In some examples, the Non-RT RIC 1215 or the Near-RT RIC 1225 may be configured to tune RAN behavior or performance. For e14ample, the Non-RT RIC 1215 may monitor long-term trends and patterns for performance and employ AI/ML models to perform corrective actions through the SMO Framework 1205 (such as reconfiguration via O1) or via creation of RAN management policies (such as A1 policies) .

EXEMPLARY ASPECTS OF THE DISCLOSURE

Aspect 1. A method of wireless communication performed by a first wireless communication device, the method comprising: communicating, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and communicating, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, and wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein the third association is the same as one of the first association or the second association; or the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Aspect 2. The method of aspect 1, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein the third association is the same as the first association and the fourth association is the same as the second association.

Aspect 3. The method of aspect 1, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.

Aspect 4. The method of aspect 1, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third association is the same as one of the first association or the second association.

Aspect 5. The method of aspect 1, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator.

Aspect 6. The method of aspect 1, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association, wherein: the third association is the same as one of the first association or the second association; and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.

Aspect 7. The method of any of aspects 1-6, further comprising communicating a radio resource control configuration comprising the one or more TA association configurations, the one or more TA association configurations indicating the first association, the second association, and the third association.

Aspect 8. The method of any of aspects 1-6, wherein the one or more TA association configurations are indicated by a fixed network configuration.

Aspect 9. The method of any of aspects 1-8, wherein: the first wireless communication device comprises a base station (BS) and the second wireless communication device comprises a user equipment (UE) ; the communicating the first cell configuration comprises transmitting, by the BS to the UE, the first cell configuration; and the communicating the second cell configuration comprises transmitting, by the BS to the UE, the second cell configuration.

Aspect 10. The method of any of aspects 1-8, wherein: the first wireless communication device comprises a user equipment (UE) and the second wireless communication device comprises a base station (BS) ; the communicating the first cell configuration comprises receiving, by the UE from the BS, the first cell configuration; and the communicating the second cell configuration comprises receiving, by the UE from the BS, the second cell configuration.

Aspect 10. A user equipment (UE) comprising a transceiver and a processor in communication with the transceiver, wherein the UE is configured to perform the aspects of any of aspects 1-8 and 10.

Aspect 11. A base station (BS) comprising a transceiver and a processor in communication with the transceiver, wherein the BS is configured to perform the aspects of any of aspects 1-9.

Aspect 12. A computer-readable medium having program recorded thereon, wherein the program code comprises instructions executable by a processor to cause a first wireless communication device to perform the actions of any of aspects 1-9.

Aspect 13. A user equipment (UE) comprising means for performing the actions of any of aspects 1-8 and 10.

Aspect 14. A base station (BS) comprising means for performing the actions of any of aspects 1-9.

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.

The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, an 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, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described above can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Also, as used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive 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) .

As those of some skill in this art will by now appreciate and depending on the particular application at hand, many modifications, substitutions and variations can be made in and to the materials, apparatus, configurations and methods of use of the devices of the present disclosure without departing from the spirit and scope thereof. In light of this, the scope of the present disclosure should not be limited to that of the particular aspects illustrated and described herein, as they are merely by way of some examples thereof, but rather, should be fully commensurate with that of the claims appended hereafter and their functional equivalents.

Claims

A method of wireless communication performed by a first wireless communication device, the method comprising:

communicating, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and

communicating, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, and

wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein

the third association is the same as one of the first association or the second association; or

the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The method of claim 1, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein:

the third association is the same as the first association and the fourth association is the same as the second association; or

each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The method of claim 1, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third association is the same as one of the first association or the second association.
The method of claim 1, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The method of claim 1, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association, wherein:

the third association is the same as one of the first association or the second association; and

the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The method of claim 1, further comprising communicating a radio resource control configuration comprising the one or more TA association configurations, the one or more TA association configurations indicating the first association, the second association, and the third association.
The method of claim 1, wherein the one or more TA association configurations are indicated by a fixed network configuration.
The method of claim 1, wherein:

the first wireless communication device comprises a base station (BS) and the second wireless communication device comprises a user equipment (UE) ;

the communicating the first cell configuration comprises transmitting, by the BS to the UE, the first cell configuration; and

the communicating the second cell configuration comprises transmitting, by the BS to the UE, the second cell configuration.
The method of claim 1, wherein:

the first wireless communication device comprises a user equipment (UE) and the second wireless communication device comprises a base station (BS) ;

the communicating the first cell configuration comprises receiving, by the UE from the BS, the first cell configuration; and

the communicating the second cell configuration comprises receiving, by the UE from the BS, the second cell configuration.
A first wireless communication device, comprising:

a transceiver; and

a processor in communication with the transceiver, wherein the first wireless communication device is configured to:

communicate, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and

communicate, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, and

wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein

the third association is the same as one of the first association or the second association; or

the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 10, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein:

the third association is the same as the first association and the fourth association is the same as the second association; or

each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 10, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third association is the same as one of the first association or the second association.
The first wireless communication device of claim 10, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 10, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association, wherein:

the third association is the same as one of the first association or the second association; and

the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 10, wherein the first wireless communication device is further configured to communicate a radio resource control configuration comprising the one or more TA association configurations, the one or more TA association configurations indicating the first association, the second association, and the third association.
The first wireless communication device of claim 10, wherein the one or more TA association configurations are indicated by a fixed network configuration.
The first wireless communication device of claim 10, wherein:

the first wireless communication device comprises a base station (BS) and the second wireless communication device comprises a user equipment (UE) ;

the first wireless communication device configured to communicate the first cell configuration comprises the first wireless communication device configured to transmit, to the UE, the first cell configuration; and

the first wireless communication device configured to communicate the second cell configuration comprises the first wireless communication device configured to transmit, to the UE, the second cell configuration.
The first wireless communication device of claim 10, wherein:

the first wireless communication device comprises a user equipment (UE) and the second wireless communication device comprises a base station (BS) ;

the first wireless communication device configured to communicate the first cell configuration comprises the first wireless communication device configured to receive, from the BS, the first cell configuration; and

the first wireless communication device configured to communicate the second cell configuration comprises the first wireless communication device configured to receive, from the BS, the second cell configuration.
A non-transitory, computer-readable medium having program code recorded thereon, wherein the program code comprises instructions executable by a first wireless communication device to cause a second wireless communication device to:

communicate, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and

communicate, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association, and

wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein

the third association is the same as one of the first association or the second association; or

the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The non-transitory, computer-readable medium of claim 19, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein:

the third association is the same as the first association and the fourth association is the same as the second association; or

each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The non-transitory, computer-readable medium of claim 19, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third association is the same as one of the first association or the second association.
The non-transitory, computer-readable medium of claim 19, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The non-transitory, computer-readable medium of claim 19, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association, wherein:

the third association is the same as one of the first association or the second association; and

the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The non-transitory, computer-readable medium of claim 19, wherein the program code further comprising instructions for causing the first wireless communication device to communicate a radio resource control configuration comprising the one or more TA association configurations, the one or more TA association configurations indicating the first association, the second association, and the third association.
The non-transitory, computer-readable medium of claim 19, wherein the one or more TA association configurations are indicated by a fixed network configuration.
A first wireless communication device, comprising:

means for communicating, with a second wireless communication device, a first cell configuration associated with a first cell, the first cell configuration including a first timing advance group (TAG) indicator and a second TAG indicator, wherein the first TAG indicator is associated with a first control resource set (CORESET) pool index by a first association and the second TAG indicator is associated with a second CORESET pool index by a second association; and

means for communicating, with the second wireless communication device, a second cell configuration associated with a second cell, the second cell configuration including a third TAG indicator, wherein the third TAG indicator is associated with a third CORESET pool index by a third association,

wherein the first association, the second association, and the third association are based on one or more timing advance (TA) association configurations, and wherein

the third association is the same as one of the first association or the second association; or

the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 26, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth control resource set pool index by a fourth association, wherein:

the third association is the same as the first association and the fourth association is the same as the second association; or

each of the third TAG indicator and the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 26, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third association is the same as one of the first association or the second association.
The first wireless communication device of claim 26, wherein the second cell configuration includes a single TAG indicator, the single TAG indicator being the third TAG indicator, and wherein the third TAG indicator is different from the first TAG indicator and the second TAG indicator.
The first wireless communication device of claim 26, wherein the second cell configuration further includes a fourth TAG indicator associated with a fourth CORESET pool index by a fourth association, wherein:

the third association is the same as one of the first association or the second association; and

the fourth TAG indicator is different from the first TAG indicator and the second TAG indicator.