Multi-TRP SRS resource set

Abstract

Various aspects relate to configuration of a single sounding reference signal (SRS) resource set for a UE, the SRS resource set comprising SRS resources associated with multiple different transmit receive points (TRPs). A radio access network (RAN) entity that may be associated with one or more of the TRPs may configure an SRS configuration for the SRS resource set and send the SRS configuration to the UE. The UE may then send multiple SRSs to multiple TRPs based on the SRS configuration. Other aspects, features, and examples are also claimed and described.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to and the benefits of pending non-provisional application No. 17 / 373,583 filed with the U.S. Patent Office on July 21, 2021, and provisional application No. 63 / 051,348 filed with the U.S. Patent Office on July 13, 2020, which are assigned to the assignee of this application and are hereby expressly incorporated herein by reference as if fully set forth below and for all applicable purposes. Technical Field

[0003] In general, the techniques discussed below relate to wireless communication networks, and more specifically, the techniques discussed below relate to configuration of sounding reference signal (SRS) resources in beam-based communication scenarios. Background Art

[0004] In wireless communication systems, such as those specified in the standards for 5G New Radio (NR), base stations and user equipment (UE) can utilize beamforming to compensate for high path loss and short distances. Beamforming is a signal processing technique used with antenna arrays for directional signal transmission and / or reception. Each antenna in the antenna array transmits a signal that combines with other signals from other antennas of the same array in such a way that signals at certain angles experience constructive interference, while other signals experience destructive interference.

[0005] The base station and the UE may select one or more beam pair links (BPLs) for communication between them on the downlink and / or uplink. Each BPL includes corresponding transmit beams and receive beams on the base station and the UE. For example, on the uplink, the BPL includes a transmit beam on the UE and a receive beam on the base station. The base station and the UE may use a downlink beam management scheme and / or an uplink beam management scheme to select one or more beams forming the BPL for transmitting uplink signals and downlink signals therebetween. In the example of the uplink beam management scheme, an uplink beam (e.g., an uplink BPL) may be selected by the base station based on a received beamformed uplink reference signal (such as an SRS). When the channel is reciprocal, the base station may also derive a downlink beam (e.g., a downlink BPL) to be communicated with the UE based on the received SRS.

[0006] The UE may send an SRS according to the SRS resources configured by the base station. The SRS resources define the time-frequency resource locations and other parameters associated with the transmission of the SRS. One or more SRS resources may be included in an SRS resource set, which may be configured to implement aperiodic, semi-persistent, or periodic transmission of an SRS generated based on the SRS resources within the SRS resource set. Summary of the invention

[0007] In order to provide a basic understanding of one or more aspects of the present disclosure, an overview of such aspects is given below. This overview is not a general review of all expected features of the present disclosure, and is neither intended to identify the key or important elements of all aspects of the present disclosure, nor is it intended to describe the scope of any or all aspects of the present disclosure. Its sole purpose is to present some concepts of one or more aspects of the present disclosure in a form as a prelude to a more detailed description given later.

[0008] In one example, a method for wireless communication at a user equipment (UE) in a wireless communication network is disclosed. The method includes: receiving a sounding reference signal (SRS) configuration for an SRS resource set. The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). The method also includes: transmitting a plurality of SRSs to the plurality of TRPs according to the SRS configuration.

[0009] Another example provides a UE in a wireless communication network, comprising a memory and a processor coupled to the memory. The processor and the memory may be configured to receive a sounding reference signal (SRS) configuration for an SRS resource set. The SRS resource set may include multiple SRS resources associated with multiple transmit receive points (TRPs). The processor and the memory may also be configured to send multiple SRSs to the multiple TRPs according to the SRS configuration.

[0010] Another example provides a UE in a wireless communication network. The UE may include: a unit for receiving a sounding reference signal (SRS) configuration for an SRS resource set. The SRS resource set may include multiple SRS resources associated with multiple transmit receive points (TRPs). The UE may also include: a unit for sending multiple SRSs to the multiple TRPs according to the SRS configuration.

[0011] Another example provides a non-transitory computer-readable medium, comprising code for causing one or more processors of a UE to perform the following operations: receiving an SRS configuration for a sounding reference signal (SRS) resource set. The SRS resource set may include multiple SRS resources associated with multiple transmit receive points (TRPs). The non-transitory computer-readable medium may also include code for causing the one or more processors of the UE to perform the following operations: sending multiple SRSs to the multiple TRPs according to the SRS configuration.

[0012] In another example, a method for wireless communication at a radio access network (RAN) entity in a wireless communication network is disclosed. The method includes: sending a sounding reference signal (SRS) configuration for a set of SRS resources for a user equipment (UE) for the UE. The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). The method also includes: receiving at least one SRS from the UE according to the SRS configuration.

[0013] Another example provides a RAN entity in a wireless communication network, comprising a memory and a processor coupled to the memory. The processor and the memory may be configured to: send a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE) for the UE. The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). The processor and the memory may be configured to: receive at least one SRS from the UE according to the SRS configuration.

[0014] Another example provides a RAN entity in a wireless communication network. The RAN entity may include: a unit for sending a sounding reference signal (SRS) configuration for a sounding reference signal (SRS) resource set for a user equipment (UE) for the UE. The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit reception points (TRPs). The RAN entity may also include: a unit for receiving at least one SRS from the UE according to the SRS configuration.

[0015] Another example provides a non-transitory computer-readable medium, comprising code for causing one or more processors of a RAN entity to perform the following operations: sending an SRS configuration for a sounding reference signal (SRS) resource set for a user equipment (UE) for the UE. The SRS resource set may include multiple SRS resources associated with multiple transmit reception points (TRPs). The non-transitory computer-readable medium may also include code for causing the one or more processors of the RAN entity to perform the following operations: receiving at least one SRS from the UE according to the SRS configuration.

[0016] In another example, a method for wireless communication at a radio access network (RAN) entity in a wireless communication network is disclosed. The method includes: configuring a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE). The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). The method also includes: sending the SRS configuration for the SRS resource set to the UE; and receiving at least one SRS from the UE according to the SRS configuration.

[0017] Another example provides a RAN entity in a wireless communication network, comprising a memory and a processor coupled to the memory. The processor and the memory may be configured to: configure a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE). The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). The processor and the memory may be configured to: send the SRS configuration for the SRS resource set to the UE; and receive at least one SRS from the UE according to the SRS configuration.

[0018] Another example provides a RAN entity in a wireless communication network. The RAN entity may include: a unit for configuring a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE). The SRS resource set may include a plurality of SRS resources associated with a plurality of transmit reception points (TRPs). The RAN entity may also include: a unit for sending the SRS configuration for the SRS resource set to the UE; and a unit for receiving at least one SRS from the UE according to the SRS configuration.

[0019] Another example provides a non-transitory computer-readable medium, comprising code for causing one or more processors of a RAN entity to perform the following operations: configuring a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE). The SRS resource set may include multiple SRS resources associated with multiple transmit receive points (TRPs). The non-transitory computer-readable medium may also include code for causing the one or more processors of the RAN entity to perform the following operations: sending the SRS configuration for the SRS resource set to the UE; and receiving at least one SRS from the UE according to the SRS configuration.

[0020] After reviewing the following detailed description, these and other aspects will become more fully understood.After reviewing the following description of specific exemplary aspects in conjunction with the accompanying drawings, other aspects, features and examples will become apparent to those skilled in the art.Although features may be discussed below with respect to certain aspects and the accompanying drawings, all aspects may include one or more features in the advantageous features discussed herein.In other words, although one or more aspects may be discussed as having certain advantageous features, one or more features in such features may also be used according to the various aspects discussed herein.In a similar manner, although exemplary aspects may be discussed below as equipment, system or method aspects, such exemplary aspects may be implemented in various devices, systems and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a conceptual diagram of an example of a radio access network in accordance with some aspects.

[0022] Figure 2 is a diagram illustrating an example of a frame structure for use in a radio access network in accordance with some aspects.

[0023] Figure 3 is a block diagram illustrating a wireless communication system supporting beamforming and / or multiple-input multiple-output (MIMO) communications in accordance with some aspects.

[0024] Figure 4 is a diagram illustrating an example of communication between a base station and a UE using beamforming in accordance with some aspects.

[0025] Figure 5A and 5B is a diagram illustrating an example of sounding reference signal (SRS) resources in accordance with some aspects.

[0026] Fig. 6A , 6B 6C are diagrams illustrating example SRS resource sets, each SRS resource set including SRS resources, according to some aspects.

[0027] Fig. 7A is a diagram illustrating a wireless communication network including multiple transmit receive points (TRPs) for wireless communication with a UE according to some aspects.

[0028] Figure 7B is a diagram illustrating an example of a multi-TRP SRS resource set according to some aspects.

[0029] Figure 8 is a signaling diagram illustrating an example of signaling between a UE and multiple TRPs utilizing multiple TRP SRS resource sets according to some aspects.

[0030] Fig. 9 is a signaling diagram illustrating an example of signaling between a UE and multiple TRPs for power control of SRS resources according to some aspects.

[0031] Fig.10 is a signaling diagram illustrating another example of signaling between a UE and multiple TRPs for power control of SRS resources according to some aspects.

[0032] Fig.11 is a block diagram illustrating an example of a hardware implementation for a UE employing a processing system according to some aspects.

[0033] Fig.12 is a block diagram illustrating an example of a hardware implementation for a Radio Access Network (RAN) entity employing a processing system according to some aspects.

[0034] Fig.13 is a flow chart of an example method for a UE to utilize multiple TRP SRS resource sets according to some aspects.

[0035] Fig.14 is a flow chart of an exemplary method for a RAN entity to configure multiple TRP SRS resource sets according to some aspects.

[0036] Fig.15 is a flow chart of an example method for a RAN entity to utilize multiple TRP SRS resource sets according to some aspects.

[0037] Fig.16 is a diagram that provides a high-level diagram of one example of a network configuration including an integrated access backhaul (IAB) network in accordance with some aspects.

[0038] Fig.17 is a diagram illustrating an example of IAB node functionality within an IAB network in accordance with some aspects. DETAILED DESCRIPTION

[0039] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configuration in which the concepts described herein may be practiced. In order to provide a comprehensive understanding of each concept, the detailed description includes specific details. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some cases, well-known structures and components are shown in block diagram form in order to avoid blurring such concepts.

[0040] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc. based on frequency / wavelength. In 5G NR, two initial operating bands have been identified with the frequency range names FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "sub-6 GHz" band in various documents and articles. Similar naming issues sometimes arise with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although it is different from the extremely high frequency (EHF) band (30 GHz-300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0041] The frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range name FR3 (7.125GHz-24.25GHz). The frequency bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and therefore the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations beyond 52.6GHz. For example, three higher operating bands have been identified as frequency range names FR4-a or FR4-1 (52.6GHz-71GHz), FR4 (52.6GHz-114.25GHz) and FR5 (114.25GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

[0042] In view of the above, unless otherwise specifically stated, it should be understood that if the term "sub-6 GHz" or the like is used herein, it can be broadly referred to as a frequency that can be less than 6 GHz, can be within FR1, or can include mid-band frequencies. In addition, unless otherwise specifically stated, it should be understood that if the term "millimeter wave" or the like is used herein, it can be broadly referred to as a frequency that can include mid-band frequencies, can be within FR2, FR4, FR4-a or FR4-1 and / or FR5, or can be within the EHF band.

[0043] Although various aspects and examples are described in this application by the description of some examples, it will be understood by those skilled in the art that additional implementations and use cases can be generated in many different arrangements and scenarios. The innovation described herein can be implemented across many different platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, aspects and / or uses can be generated via integrated chip examples and other devices based on non-module components (e.g., end-user devices, vehicles, communication equipment, computing equipment, industrial equipment, retail / purchase equipment, medical equipment, AI-enabled devices, etc.). Although some examples may or may not be specifically for use cases or applications, there may be a variety of applicable scopes for the described innovations. Implementations may have a range from chip-level or modular components to non-modular, non-chip-level implementations, and further to aggregated, distributed, or OEM devices or systems incorporating one or more aspects of the described innovations. In some practical settings, the devices incorporating the described aspects and features may also necessarily include additional components and features for the implementation and practice of the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily include multiple components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / accumulators, etc.). The innovations described herein are intended to be practiced in a variety of devices, chip-level components, systems, distributed arrangements, end-user equipment, etc., having different sizes, shapes, and configurations.

[0044] To facilitate selection of one or more uplink beams for transmitting uplink signals from a UE to one or more transmit receive points (TRPs), the UE may send a sounding reference signal (SRS) to each of these TRPs for measurement thereof. For example, if the UE is fixed and has reduced capability, transmission of SRS to multiple TRPs may be utilized, where TRP spatial diversity may help mitigate channel / path blocking or temporary shadowing (e.g., a temporary obstacle) of one TRP (e.g., the TRP). In addition, in the case where the UE is fixed and rotating (e.g., the UE is a video surveillance camera), the UE may be exposed to coverage of multiple TRPs while rotating, and the UE may perform selection of uplink beams between the TRPs. In addition, if the UE is configured for layer 1 (L1) based cell mobility (where L1 messages rather than RRC messages are used for switching between TRPs belonging to the same base station (e.g., gNode B (gNB))), the UE may obtain SRS measurements from multiple TRPs for switching and beam selection.

[0045] In some examples, the UE may be configured with a separate SRS resource set for each TRP in a TRP. In this example, to collect SRS measurements on, for example, two TRPs, the UE may send a first SRS set to the first TRP using a first SRS resource set configured for the first TRP, and then subsequently send a second SRS set to the second TRP using a different second SRS resource set configured for the second TRP. Using two separate SRS resource sets (one for each TRP) delays SRS measurements and increases resource usage.

[0046] Various aspects of the present disclosure relate to configuration of a single SRS resource set for a UE, the SRS resource set including SRS resources associated with multiple different TRPs. A radio access network (RAN) entity that may be associated with one or more of the TRPs may configure an SRS configuration for the SRS resource set and send the SRS configuration to the UE. The UE may then send multiple SRSs to multiple TRPs based on the SRS configuration.

[0047] The SRS resource set can be configured as a periodic SRS resource set, a semi-persistent SRS resource set, or triggered aperiodically. In some examples, the TRPs may belong to the same cell or different cells. In addition, the TRPs may belong to the same timing advance group (TAG) or different TAGs. In examples where the TRPs belong to different TAGs, a gap length between corresponding SRS resources associated with each TRP in the TRPs may be provided to accommodate different timing advances to be applied to the SRS resources. In some examples, the gap length may be determined as a function of different timing advance commands received for each TAG in the TAG. In other examples, the gap length may be configured by a RAN entity.

[0048] In some examples, the quasi co-location (QCL) association for SRS resources can be the same or different between TRPs. In examples where the QCL association for SRS resources is different between TRPs, a gap length between the corresponding SRS resources associated with each TRP in the TRP can be provided to enable antenna port switching between SRS resources associated with different TRPs. In some examples, the gap length can be based on the capabilities of the UE. In other examples, the gap length can be configured by a RAN entity.

[0049] The transmit power used for the SRS resources may be controlled per TRP, or a common transmit power may be used for all TRPs. For example, the UE may receive multiple transmit power control (TPC) commands (each TPC command being associated with one of the multiple TRPs), and based on the TPC commands, send SRS to the multiple TRPs using a corresponding transmit power for each of the multiple TRPs. As another example, the UE may receive a single TPC command applicable to each TRP in the TRPs, and based on the single TPC command, send SRS to the multiple TRPs using the same transmit power. In some examples, a single TPC command is received for a set of SRS resources associated with one of the TRPs, and the UE may apply the TPC command to SRS resources associated with other TRPs.

[0050] The SRS configuration may define SRS resource set parameters for an SRS resource set. For example, each SRS resource may be configured by a set of SRS resource parameters. The SRS resource parameters may include, for example, a port set, a bandwidth, a number of symbols, a transmission comb structure (e.g., SRS is transmitted every N subcarriers, where N=2 or 4), repetitions, starting symbols, etc. The SRS resource parameters for each SRS resource in the SRS resource together form the SRS resource set parameters included in the SRS configuration. In addition, the SRS configuration may also include additional parameters applicable to the SRS resource set as a whole. For example, the SRS configuration for an aperiodic SRS resource set may also include a trigger state for triggering an aperiodic SRS resource set, a time slot offset between the downlink control information (DCI) including the trigger state and the transmission of the SRS, and a channel state information reference signal (CSI-RS) resource identifier (CRI) associated with the aperiodic SRS resource set. As another example, the SRS configuration for a periodic or semi-persistent SRS resource set may indicate the period of transmission of the SRS.

[0051] In some examples, the SRS configuration may include a common SRS resource set parameter set for multiple TRPs. For example, the SRS configuration may configure an SRS resource set including one or more SRS resources, each SRS resource including common SRS resource parameters (e.g., transmission comb structure, port, number of symbols, repetition, etc.). In this example, the starting symbol may be indicated individually, or a rule may be defined to indicate the starting symbol. In addition, each SRS resource in the SRS resource set in the common SRS resource set will be associated with the same beam. In some examples, when a common SRS resource set parameter set is used, each SRS resource in the SRS resource set may be associated with all TRPs. For example, each TRP may receive all SRS configured in the SRS resource set. In other examples, each SRS resource in the SRS resource set including the common SRS resource set parameters may be associated with a specific TRP. In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each TRP in the multiple TRPs. For example, the SRS configuration may include multiple TRP SRS configurations, each TRP SRS configuration being associated with a corresponding TRP. Each TRP SRS configuration may configure one or more SRS resources associated with a particular TRP, where SRS resource parameters may vary between TRP SRS resource configurations. Thus, each TRP SRS configuration includes SRS resource set parameters that configure specific SRS resources for that TRP.

[0052] The SRS configuration may be provided to the UE in a radio resource control (RRC) message sent to the UE. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC configuration information element (IE)) that includes the SRS configuration. For example, the RRC configuration may include a sequence of TRP SRS configurations. In an example in which the SRS configuration includes a common SRS resource set parameter set, the sequence may have a length of 1 (e.g., a single TRPSRS configuration including common SRS resource set parameters). In other examples, the RRC message may include multiple RRC configurations, each of which includes one of the TRP SRS configurations. In an example in which the SRS resource set is a non-periodic SRS resource set, a code point pointing to a single RRC configuration or multiple RRC configurations may be used to trigger the SRS configuration. By utilizing a single SRS resource set including SRS resources associated with multiple different TRPs for the UE, delays in SRS measurements may be reduced, resulting in lower latency for uplink beam selection. In addition, downlink resource usage may be further reduced by sending a single SRS configuration for multiple TRPs to the UE.

[0053] The various concepts presented throughout this disclosure may be implemented in a wide variety of telecommunication systems, network architectures and communication standards. Figure 1 , a schematic diagram of a radio access network 100 is provided as an illustrative example and not by way of limitation. The RAN 100 may implement any one or more suitable wireless communication technologies to provide radio access. As an example, the RAN 100 may operate in accordance with the 3rd Generation Partnership Project (3GPP) New Radio (NR) specification (often referred to as 5G). As another example, the RAN 100 may operate in accordance with a mix of 5G NR and Evolved Universal Terrestrial Radio Access Network (eUTRAN) standards (often referred to as LTE). 3GPP refers to this hybrid RAN as the Next Generation RAN or NG-RAN. Of course, many other examples may be utilized within the scope of the present disclosure.

[0054] The geographical area covered by the radio access network 100 may be divided into a plurality of cellular areas (cells), which may be uniquely identified by a user equipment (UE) based on an identity broadcast from an access point or base station over the geographical area. Figure 1 Macro cells 102, 104, 106, 142, and 146a / 146b and small cells 108 are shown, each of which may include one or more sectors (not shown). A sector is a sub-area of ​​a cell. All sectors within a cell are served by the same base station. A radio link within a sector may be identified by a single logical identifier belonging to the sector. In a cell divided into sectors, multiple sectors within a cell may be formed by antenna groups, each of which is responsible for communicating with a UE in a portion of the cell.

[0055] Typically, a base station (BS) serves each cell. Broadly speaking, a base station is a network element or entity in a radio access network that is responsible for radio transmission and reception to or from a UE in one or more cells. A BS may also be referred to by those skilled in the art as a base transceiver station (BTS), a radio base station, a radio transceiver, a transceiver functional unit, a basic service set (BSS), an extended service set (ESS), an access point (AP), a Node B (NB), an evolved Node B (eNB), a gNodeB (gNB), a transmit receive point (TRP), or some other appropriate term.

[0056] exist Figure 1In the example shown, three base stations 110, 112 and 114 are shown in cells 102, 104 and 106, respectively; and a fourth base station 116 is shown as controlling remote radio heads (RRHs) 144 and 148 in cells 142 and 146a / 146b. That is, the base station can have an integrated antenna or can be connected to the antenna or RRH by a feeder cable. In the example shown, cells 102, 104, 106, 142 and 146a / 146b can be referred to as macro cells because base stations 110, 112, 114 and 116 support cells with large sizes. In addition, base station 118 is shown in a small cell 108 (e.g., a micro cell, a micro cell, a femto cell, a home base station, a home node B, a home evolved node B, etc.), which may overlap with one or more macro cells. In this example, cell 108 can be referred to as a small cell because base station 118 supports cells with relatively small sizes. Cell size setting can be done according to system design and component constraints. It is to be understood that the radio access network 100 may include any number of wireless base stations and cells. In addition, relay nodes may be deployed to extend the size or coverage area of ​​a given cell. Base stations 110, 112, 114, 116, and 118 provide wireless access points to the core network for any number of mobile devices.

[0057] Figure 1 Also included is an unmanned aerial vehicle (UAV) 120 (such as a quadcopter or drone) that can be configured to act as a base station. That is, in some examples, the cell may not necessarily be stationary, and the geographic area of ​​the cell may move according to the location of a mobile base station (such as UAV 120).

[0058] Typically, a base station may include a backhaul interface for communicating with a backhaul portion of a network (not shown). The backhaul may provide a link between the base station and a core network (not shown), and in some examples, the backhaul may provide interconnection between respective base stations. The core network may be part of a wireless communication system and may be independent of the radio access technology used in the radio access network. Various types of backhaul interfaces may be employed, such as a direct physical connection, a virtual network, or a similar interface using any suitable transport network.

[0059] RAN 100 is shown as supporting wireless communications for multiple mobile devices. Mobile devices are generally referred to as user equipment (UE) in standards and specifications published by the Third Generation Partnership Project (3GPP), but may also be referred to as mobile stations (MS), subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals (AT), mobile terminals, wireless terminals, remote terminals, handsets, terminals, user agents, mobile clients, clients, or some other appropriate terminology by those skilled in the art. UE may be a device that provides access to network services to a user.

[0060] In this document, a "mobile" device does not necessarily need to have the ability to move, but can be fixed. The term mobile device or mobile device refers broadly to a variety of devices and technologies. For example, some non-limiting examples of mobile devices include mobile stations, cellular phones (mobile phones), smart phones, session initiation protocol (SIP) phones, laptops, personal computers (PCs), notebook computers, netbooks, smart books, tablet devices, personal digital assistants (PDAs), and (for example, corresponding to the "Internet of Things" (IoT)) various embedded systems. The mobile device can also be a car or other means of transportation, a remote sensor or actuator, a robot or a robot-like device, a satellite radio unit, a global positioning system (GPS) device, a target tracking device, a drone, a multi-wing aircraft, a quad-wing aircraft, a remote control device, a consumer device and / or a wearable device (such as glasses, wearable cameras, virtual reality devices, smart watches, health or fitness trackers, digital audio players (e.g., MP3 players), cameras, game consoles, etc.). The mobile device can also be a digital home or smart home device, such as home audio, video and / or multimedia equipment, electrical appliances, vending machines, smart lighting, home security systems, smart meters, etc. The mobile device may additionally be a smart energy device, a security device, a solar panel or solar array, a municipal infrastructure device that controls power (e.g., a smart grid), lighting, water, etc.; industrial automation and enterprise devices; logistics controllers; agricultural equipment, etc. Further, the mobile device may provide connected medicine or telemedicine support (e.g., telehealth care). Telemedicine devices may include telemedicine monitoring devices and telemedicine management devices, whose communications may be prioritized over other types of information, for example, in terms of priority access for transmission of critical service data, and / or associated QoS for transmission of critical service data.

[0061] Within the RAN 100, a cell may include UEs that may communicate with one or more sectors of each cell. For example, UEs 122 and 124 may communicate with base station 110; UEs 126 and 128 may communicate with base station 112; UEs 130 and 132 may communicate with base station 114; UE 134 may communicate with base station 118; UEs 138 and 140 may communicate with base station 116 via one or more of RRHs 144 and 148; and UE 136 may communicate with mobile base station 120. Here, each base station 110, 112, 114, 116, 118, and 120 may be configured to provide an access point to a core network (not shown) for all UEs in the corresponding cell. In another example, a mobile network node (e.g., UAV 120) may be configured to act as a UE. For example, UAV 120 may operate within cell 102 by communicating with base station 110.

[0062] In some examples, access to the air interface may be scheduled, wherein a scheduling entity (e.g., base station 112) allocates resources for communication between some or all devices and apparatuses within its service area or cell. In the present disclosure, as further discussed below, a scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more scheduled entities. That is, for scheduled communications, a UE (e.g., UE 126) that may be a scheduled entity may utilize resources allocated by the scheduling entity 112.

[0063] The base station is not the only entity that can act as a scheduling entity. That is, in some examples, a UE can act as a scheduling entity that schedules resources for one or more scheduled entities (e.g., one or more other UEs). And as discussed more below, a UE can communicate directly with other UEs in a peer-to-peer (P2P) manner and / or in a relay configuration.

[0064] In other aspects of RAN 100, sidelink signals can be used between UEs without having to rely on scheduling or control information from a base station. For example, two or more UEs (e.g., UE 138 and 140) can use peer-to-peer (P2P) or sidelink signals 137 to communicate with each other without relaying the communication through a base station (e.g., base station 144). In some examples, the sidelink signal 137 includes sidelink traffic and sidelink control. In some examples, UE 138 and 140 can each act as a scheduling entity or initiate (e.g., send) a sidelink device and / or be scheduled entity or receive a sidelink device. For example, UE 138 and 140 can act as a scheduling entity or a scheduled entity in a P2P network, a device-to-device (D2D), a vehicle-to-vehicle (V2V) network, a vehicle-to-everything (V2X), a mesh network, or other appropriate networks.

[0065] In the RAN 100, the ability of a UE to communicate while moving (independent of its location) is called mobility. Various physical channels between the UE and the RAN are typically established, maintained, and released under the control of an access and mobility management function (AMF), which may include: a security context management function (SCMF), which manages security contexts for both control plane functions and user plane functions; and a security anchor function (SEAF) that performs authentication. In some examples, during a call with a scheduling entity, or at any other time, the UE may monitor various parameters of signals from its serving cell and various parameters of neighboring cells. Based on the quality of these parameters, the UE may maintain communication with one or more of the neighboring cells. During this time, if the UE moves from one cell to another, or if the signal quality from the neighboring cell exceeds the signal quality from the serving cell for a given amount of time, the UE may perform a handoff or handover from the serving cell to the neighboring (target) cell. For example, the UE 124 may move from a geographic area corresponding to its serving cell 102 to a geographic area corresponding to a neighboring cell 106. When the signal strength or quality from neighbor cell 106 exceeds the signal strength or quality of its serving cell 102 for a given amount of time, UE 124 may send a report message indicating this condition to its serving base station 110. In response, UE 124 may receive a handover command, and the UE may perform a handover to cell 106.

[0066] Wireless communication between RAN 100 and UE (e.g., UE 122 or 124) can be described as utilizing an air interface. Transmissions from a base station (e.g., base station 110) to one or more UEs (e.g., UE 122 and 124) over the air interface can be referred to as downlink (DL) transmissions. According to certain aspects of the present disclosure, the term downlink can refer to point-to-multipoint transmissions originating from a scheduling entity (further described below; e.g., base station 110). Another way to describe the scheme can be to use the term broadcast channel multiplexing. Transmissions from a UE (e.g., UE 122) to a base station (e.g., base station 110) can be referred to as uplink (UL) transmissions. According to further aspects of the present disclosure, the term uplink can refer to point-to-point transmissions originating from a scheduled entity (further described below; e.g., UE 122).

[0067] For example, DL transmissions may include unicast or broadcast transmissions of control information and / or data (e.g., user data traffic or other types of traffic) from a base station (e.g., base station 110) to one or more UEs (e.g., UEs 122 and 124), while UL transmissions may include transmissions of control information and / or traffic information originating from a UE (e.g., UE 122). In addition, uplink and / or downlink control information and / or traffic information may be divided into frames, subframes, time slots, and / or symbols in time. As used herein, a symbol may refer to a time unit in which one resource element (RE) is carried per subcarrier in an orthogonal frequency division multiplexing (OFDM) waveform. A time slot may carry 7 or 14 OFDM symbols. A subframe may refer to a duration of 1 ms. Multiple subframes or time slots may be grouped together to form a single frame or radio frame. In the present disclosure, a frame may refer to a predetermined duration (e.g., 10 ms) for wireless transmission, wherein each frame is composed of, for example, 10 subframes each having 1 ms. Of course, these definitions are not required, and any suitable scheme for organizing the waveforms may be utilized, and the various time divisions of the waveforms may have any suitable durations.

[0068] The air interface in the RAN 100 may utilize one or more multiplexing and multiple access algorithms to enable simultaneous communication of various devices. For example, the 5G NR specification provides multiple access for UL or reverse link transmissions from UEs 122 and 124 to base station 110, and multiplexing of DL or forward link transmissions from base station 110 to UEs 122 and 124 using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP). In addition, for UL transmissions, the 5G NR specification provides support for discrete Fourier transform spread OFDM (DFT-s-OFDM) with CP (also known as single carrier FDMA (SC-FDMA)). However, within the scope of the present disclosure, multiplexing and multiple access are not limited to the above schemes, and may be provided using time division multiple access (TDMA), code division multiple access (CDMA), frequency division multiple access (FDMA), sparse code multiple access (SCMA), resource extension multiple access (RSMA), or other appropriate multiple access schemes. In addition, multiplexing of DL transmissions from base station 110 to UEs 122 and 124 may be provided using time division multiplexing (TDM), code division multiplexing (CDM), frequency division multiplexing (FDM), orthogonal frequency division multiplexing (OFDM), sparse code multiplexing (SCM), or other suitable multiplexing schemes.

[0069] In addition, the air interface in RAN 100 can utilize one or more duplex algorithms. Duplex refers to a point-to-point communication link, in which two endpoints can communicate with each other in two directions. Full-duplex means that two endpoints can communicate with each other simultaneously. Half-duplex means that at a certain time, only one endpoint can send information to the other endpoint. Time division duplex (TDD) is often used to implement half-duplex simulation for wireless links. In TDD, transmissions in different directions on a given channel are separated from each other using time division multiplexing. That is, at certain times, the channel is dedicated to transmission in one direction, and at other times, the channel is dedicated to transmission in the other direction, where the direction can change very quickly (e.g., several times per time slot). In wireless links, full-duplex channels usually rely on physical isolation of transmitters and receivers and appropriate interference elimination techniques. Full-duplex simulation for wireless links is often implemented by utilizing frequency division duplex (FDD) or space division duplex (SDD). In FDD, transmissions in different directions can operate at different carrier frequencies (e.g., in paired spectrum). In SDD, transmissions in different directions on a given channel are separated from each other using spatial division multiplexing (SDM). In other examples, full-duplex communication can be implemented within an unpaired spectrum (e.g., within a single carrier bandwidth), where transmissions in different directions occur within different sub-bands of the carrier bandwidth. This type of full-duplex communication may be referred to herein as sub-band full-duplex (SBFD), also known as flexible duplex.

[0070] In various implementations, the air interface in the RAN 100 may utilize licensed spectrum, unlicensed spectrum, or shared spectrum. Licensed spectrum typically provides exclusive use of a portion of the spectrum by virtue of a mobile network operator purchasing a license from a government regulator. Unlicensed spectrum provides shared use of a portion of the spectrum without the need for a government-granted license. Although it is still typically necessary to comply with some technical rules to access the unlicensed spectrum, in general, any operator or device can gain access. Shared spectrum may fall between licensed spectrum and unlicensed spectrum, where some technical rules or restrictions may be required to access the spectrum, but the spectrum may still be shared by multiple operators and / or multiple RATs. For example, a holder of a license for a portion of the licensed spectrum may provide licensed shared access (LSA) to share the spectrum with other parties (e.g., with appropriate licensee-determined conditions to obtain access).

[0071] In some examples, a UE (e.g., UE 138) may be in the coverage area of ​​more than one cell (e.g., cells 142, 146a, and 146b). In this example, each RRH 144 and 148 may act as a transmit receive point (TRP) in a coordinated multi-point (CoMP), multi-radio access technology (RAT) dual connectivity (DC), or new radio (NR) DC network configuration, where downlink signals and / or uplink signals may be sent between the UE 138 and each of the TRPs 144 and 148. Figure 1 In the example shown in , RRH 148 may include two co-located TRPs, each TRP serving one of cells 146a and 146b. Each cell 146a and 146b can communicate using a corresponding radio access technology (RAT) and / or frequency range. For example, downlink data can be sent to UE138 simultaneously from each of TRPs 144 and 148 (e.g., via cells 142, 146a, and 146b) to reduce interference, increase data rate, and / or increase received power. As another example, a downlink signal can be sent from one TRP (e.g., from TRP148 via cells 146a and 146b), and an uplink signal can be received at another TRP (e.g., at TRP 144 via cell 142). In some examples, TRPs 144 and 148 can be configured using a centralized RAN architecture, where base station 116 operates to coordinate transmission and reception between UE 138 and TRPs 144 and 148 across cells 142, 146a, and 146b.

[0072] In addition, beamformed signals may be utilized between the UE 138 and each of the TRPs 144 and 148, for example, on a mmWave carrier. To facilitate transmission of uplink signals from the UE to one or both of the TRPs using uplink beams, the base station 116 may coordinate an uplink beam management scheme, wherein the UE 138 may send an uplink reference signal, such as a sounding reference signal (SRS), to each of the TRPs 144 and 148. Based on the SRS measurements, the base station 116 may select one or more uplink beams for the UE 138 to transmit uplink signals to one or more of the TRPs 144 and 148. The UE 138 may transmit the SRS according to the SRS resources configured by the base station 116. The SRS resources define the time-frequency resource locations and other parameters associated with the transmission of the SRS.

[0073] To simplify the configuration of SRS resources across multiple TRPs 144 and 148, in various aspects of the present disclosure, the base station 116 may include an SRS manager 150 for configuring an SRS resource set that includes SRS resources associated with each of the TRPs 144 and 148. The base station 116 may then send the SRS configuration of the SRS resource set to the UE 138 via, for example, the TRP 144. In addition, the UE 138 may also include an SRS manager 152 configured to generate multiple SRSs using the SRS configuration and send the multiple SRSs to the multiple TRPs 144 and 148. For example, each of the TRPs 144 and 148 may receive at least one of the SRSs sent by the UE 138 according to the SRS configuration.

[0074] Will refer to Figure 2 Various aspects of the present disclosure are described with reference to the OFDM waveform schematically shown in FIG. It will be appreciated by those skilled in the art that various aspects of the present disclosure may be applied to SC-FDMA waveforms in substantially the same manner as described herein below. That is, while some examples of the present disclosure may focus on OFDM links for clarity, it will be appreciated that the same principles may also be applied to SC-FDMA waveforms.

[0075] Now refer to Figure 2 , shows an expanded view of an exemplary DL subframe 202 showing an OFDM resource grid. However, as will be readily apparent to those skilled in the art, the PHY transmission structure for any particular application may differ from the examples described herein, depending on any number of factors. Here, time is in the horizontal direction, in units of OFDM symbols, and frequency is in the vertical direction, in units of subcarriers.

[0076] Resource grid 204 can be used to schematically represent the time-frequency resources for a given antenna port. That is, in a multiple-input multiple-output (MIMO) implementation with multiple available antenna ports, a corresponding plurality of resource grids 204 may be available for communication. Resource grid 204 is divided into a plurality of resource elements (REs) 206. RE (which is 1 carrier × 1 symbol) is the smallest discrete portion of the time-frequency grid and contains a single complex value representing data from a physical channel or signal. Depending on the modulation used in a particular implementation, each RE can represent one or more bits of information. In some examples, a block of REs may be referred to as a physical resource block (PRB) or resource block (RB) 208, which contains any appropriate number of consecutive subcarriers in the frequency domain. In one example, an RB may include 12 subcarriers, regardless of the number of digital schemes used. In some examples, depending on the digital scheme, an RB may include any appropriate number of consecutive OFDM symbols in the time domain. Within the present disclosure, it is assumed that a single RB (such as RB 208) corresponds entirely to a single communication direction (for a given device, transmission or reception).

[0077] Scheduling of a UE or sidelink device (hereinafter collectively referred to as a UE) for downlink, uplink, or sidelink transmissions typically involves scheduling one or more resource elements 206 within one or more subbands or bandwidth parts (BWPs). Thus, a UE typically utilizes only a subset of a resource grid 204. In some examples, an RB may be the smallest unit of resources that may be allocated to a UE. Thus, the more RBs scheduled for a UE, and the higher the modulation scheme selected for the air interface, the higher the data rate for the UE. The RBs may be scheduled by a base station (e.g., a gNB, eNB, etc.), or may be self-scheduled by a UE / sidelink device implementing D2D sidelink communications.

[0078] The scheduling of resources (e.g., RE 206 / RB 208) can be performed in a dynamic or semi-persistent manner to send control and / or business information. For example, a scheduling entity (e.g., a base station) can dynamically allocate a set of RE 206 / RB 208 for sending downlink control and / or data to a UE, or for sending uplink control and / or data from a UE. The base station can also semi-persistently allocate a set of RE 206 / RB 208 for periodic downlink or uplink transmission. Typically, semi-persistent scheduling (SPS) can be used for periodic communications based on defined settings. For example, SPS can be suitable for applications with small, predictable and / or periodic payloads, such as voice over Internet protocol (VoIP) applications. On the uplink, SPS resources can be referred to as configuration grants (CGs). Using CGs, scheduling information corresponding to uplink CGs can be signaled to UEs only once. Subsequently, UEs can periodically utilize resources allocated in uplink CGs without the need to receive additional scheduling information. When the CG is initially configured, a period can be established in which the UE can send user data services via semi-persistently scheduled resources.

[0079] In this diagram, RB 208 is shown as occupying less than the entire bandwidth of subframe 202, with some subcarriers shown above and below RB 208. In a given implementation, subframe 202 may have a bandwidth corresponding to any number of one or more RBs 208. Furthermore, in this diagram, while RB 208 is shown as occupying less than the entire duration of subframe 202, this is merely one possible example.

[0080] Each 1 ms subframe 202 may consist of one or more adjacent time slots. Figure 2 In the example shown, a subframe 202 includes four time slots 210 as an illustrative example. In some examples, a time slot may be defined according to a specified number of OFDM symbols with a given cyclic prefix (CP) length. For example, a time slot may include 7 or 14 OFDM symbols with a nominal CP. Another example may include micro-slots (sometimes referred to as shortened transmission time intervals (TTIs)) with shorter durations (e.g., one to three OFDM symbols). In some cases, these micro-slots or shortened transmission time intervals (TTIs) may be transmitted by occupying resources scheduled for ongoing time slot transmissions for the same or different UEs. Any number of resource blocks may be utilized within a subframe or time slot.

[0081] An expanded view of one of the time slots 210 shows that the time slot 210 includes a control region 212 and a data region 214. In general, the control region 212 may carry a control channel, and the data region 214 may carry a data channel. Figure 2 In the example shown in , the control region 212 may include downlink control information, and the data region 214 may include a downlink data channel or an uplink data channel. In addition, the time slot 210 also includes an uplink sounding reference signal (SRS) 216, which is shown as being sent at the end of the time slot 210. For example, the SRS 216 may be sent on one or more symbols within the last six symbols of the time slot 210. Of course, the time slot may contain all DL, all UL, or at least one DL portion and at least one UL portion. Figure 2 The structure shown in is merely exemplary in nature, and different time slot structures may be utilized and may include one or more regions in each of the control region and the data region.

[0082] Although not in Figure 2 208, but each RE 206 within the RB 208 may be scheduled to carry one or more physical channels, including a control channel, a shared channel, a data channel, etc. Other REs 206 within the RB 208 may also carry pilot or reference signals. These pilot or reference signals may be provided for a receiving device to perform channel estimation on the corresponding channel, which may enable coherent demodulation / detection of the control and / or data channels within the RB 208.

[0083] In some examples, time slot 210 may be used for broadcast, multicast, or unicast communications. For example, broadcast, multicast, or groupcast communications may refer to point-to-multipoint transmissions from one device (e.g., a base station, UE, or other similar device) to other devices. Here, broadcast communications are delivered to all devices, while multicast communications are delivered to multiple intended recipient devices. Unicast communications may refer to point-to-point transmissions from one device to a single other device.

[0084] In an example of cellular communication over a cellular carrier via a Uu interface, for DL ​​transmission, a scheduling entity (e.g., a base station) may allocate one or more REs 206 (e.g., within a control region 212) to one or more scheduled entities (e.g., UEs) to carry DL control information including one or more DL control channels, such as a physical downlink control channel (PDCCH). The PDCCH carries downlink control information (DCI), including, but not limited to, power control commands (e.g., one or more open-loop power control parameters and / or one or more closed-loop power control parameters), scheduling information, grants, and / or assignments of REs for DL ​​transmission and UL transmission. The PDCCH may also carry HARQ feedback transmissions, such as an acknowledgment (ACK) or a negative acknowledgment (NACK). HARQ is a technique well known to those skilled in the art, in which the integrity of a packet transmission may be checked for accuracy at the receiving side, for example, using any appropriate integrity check mechanism, such as a checksum or a cyclic redundancy check (CRC). If the integrity of the transmission is confirmed, an ACK may be sent, and if the integrity of the transmission is not confirmed, a NACK may be sent. In response to the NACK, the transmitting device may send a HARQ retransmission, which may implement append combining, incremental redundancy, and the like.

[0085] The base station may also allocate one or more REs 206 (e.g., in the control region 212 or the data region 214) to carry other DL signals, such as a demodulation reference signal (DMRS); a phase tracking reference signal (PT-RS); a channel state information (CSI) reference signal (CSI-RS); and a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The UE may utilize the PSS and SSS to achieve radio frame, subframe, time slot, and symbol synchronization in the time domain, identify the center of the channel (system) bandwidth in the frequency domain, and identify the physical cell identity (PCI) of the cell. The synchronization signals PSS and SSS and (in some examples) the PBCH and PBCH DMRS may be sent in a synchronization signal block (SSB). The PBCH may also include a master information block (MIB) containing various system information and parameters for decoding a system information block (SIB). For example, the SIB may be, for example, a system information type 1 (SIB1) that may include various additional system information. Examples of system information sent in the MIB may include, but are not limited to, subcarrier spacing, system frame number, configuration of a PDCCH control resource set (CORESET) (e.g., PDCCH CORESET0), and search space for SIB1. Examples of additional system information sent in SIB1 may include, but are not limited to, random access search space, downlink configuration information, and uplink configuration information. MIB and SIB1 together provide minimum system information (SI) for initial access.

[0086] In an UL transmission, a scheduled entity (e.g., a UE) may utilize one or more REs 206 (e.g., within a control region 212 that may be at the end of a timeslot 210) to carry UL control information (UCI) to a scheduling entity including one or more UL control channels, such as a physical uplink control channel (PUCCH). UCI may include a variety of packet types and categories. In some examples, UCI may include a scheduling request (SR), i.e., a request for a scheduling entity to schedule an uplink transmission. Here, in response to the SR sent on the UCI, the scheduling entity may send downlink control information (DCI), which may schedule resources for uplink packet transmission. UCI may also include HARQ feedback, channel state feedback (CSF) (such as a CSI report), or any other appropriate UCI. The scheduled entity (e.g., UE) may also utilize one or more REs 206 (e.g., within the control region 212 and / or the data region 214) to transmit pilots, reference signals, and other information (such as one or more DMRS and SRS 216) configured to enable or assist in decoding uplink data transmissions and / or uplink beam management.

[0087] In addition to control information, one or more REs 206 (e.g., within the data region 214) may also be allocated for data traffic. Such data traffic may be carried on one or more traffic channels (e.g., for DL ​​transmission, a physical downlink shared channel (PDSCH); or for UL transmission, a physical uplink shared channel (PUSCH)). In some examples, one or more REs 206 within the data region 214 may be configured to carry other signals (such as one or more SIBs and DMRS).

[0088] In an example of sidelink communication on a sidelink carrier via a PC5 interface, the control region 212 of the time slot 210 may include a physical sidelink control channel (PSCCH), which includes sidelink control information (SCI) sent by an initiating (transmitting) sidelink device (e.g., V2X or other sidelink device) toward a set of one or more other receiving sidelink devices. The data region 214 of the time slot 210 may include a physical sidelink shared channel (PSSCH), which includes sidelink data services sent by the initiating (transmitting) sidelink device in resources reserved by the transmitting sidelink device via the SCI on the sidelink carrier. Other information may also be sent on each RE 206 within the time slot 210. For example, HARQ feedback information may be sent from the receiving sidelink device to the transmitting sidelink device in a physical sidelink feedback channel (PSFCH) within the time slot 210. In addition, one or more reference signals (such as sidelink SSB and / or sidelink CSI-RS) may be sent within the time slot 210.

[0089] These physical channels described above are typically multiplexed and mapped to transport channels for processing at the medium access control (MAC) layer. Transport channels carry blocks of information called transport blocks (TBs). The transport block size (TBS), which may correspond to the number of bits of information, may be a controlled parameter based on the modulation and coding scheme (MCS) and the number of RBs in a given transmission.

[0090] Combination of the above Figure 1 and 2 The channels or carriers described are not necessarily all of the channels or carriers that may be utilized between a scheduling entity and a scheduled entity, and those skilled in the art will recognize that other channels or carriers may be utilized in addition to those shown, such as other traffic, control, and feedback channels.

[0091] In some aspects of the present disclosure, the scheduling entity and / or the scheduled entity may be configured for beamforming and / or multiple-input multiple-output (MIMO) techniques. Figure 3 An example of a wireless communication system 300 that supports beamforming and / or MIMO is shown. In a MIMO system, a transmitter 302 includes multiple transmit antennas 304 (e.g., N transmit antennas), and a receiver 306 includes multiple receive antennas 308 (e.g., M receive antennas). Therefore, there are N×M signal paths 310 from the transmit antennas 304 to the receive antennas 308. Each of the transmitter 302 and the receiver 306 can be implemented, for example, in a scheduling entity, a scheduled entity, or other suitable wireless communication device.

[0092] The use of this multi-antenna technology enables wireless communication systems to exploit the spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing can be used to send different data streams (also referred to as layers) simultaneously on the same time-frequency resources. Data streams can be sent to a single UE to increase the data rate, or data streams can be sent to multiple UEs to increase the overall system capacity, the latter of which is called multi-user MIMO (MU-MIMO). This is achieved by spatially precoding each data stream (e.g., multiplying the data stream by different weights and phase shifts) and then sending each spatially precoded stream through multiple transmit antennas on the downlink. The spatially precoded data streams arrive at UEs with different spatial signatures, which enables each UE in the UE to recover one or more data streams destined for the UE. On the uplink, each UE sends a spatially precoded data stream, which enables the base station to identify the source of each spatially precoded data stream.

[0093] The number of data streams or layers corresponds to the rank of the transmission. Typically, the rank of the MIMO system 300 is limited by the number of transmit antennas 304 or receive antennas 308 (whichever is lower). In addition, the channel conditions at the UE and other considerations (such as the available resources at the base station) may also affect the transmission rank. For example, the rank (and therefore the number of data streams) assigned to a specific UE on the downlink can be determined based on a rank indicator (RI) sent from the UE to the base station. The RI can be determined based on the antenna configuration (e.g., the number of transmit antennas and receive antennas) and the signal to interference and noise ratio (SINR) on each of the receive antennas measured. The RI can indicate, for example, the number of layers that can be supported under the current channel conditions. The base station can use the RI and resource information (e.g., available resources and the amount of data to be scheduled for the UE) to assign a transmission rank to the UE.

[0094] In one example, if Figure 3 As shown, a rank-2 spatial multiplexing transmission on a 2x2 MIMO antenna configuration will send one data stream from each transmit antenna 304. Each data stream follows a different signal path 310 to each receive antenna 308. The receiver 306 can then reconstruct the data stream using the signal received from each receive antenna 308.

[0095] Beamforming is a signal processing technique that can be used at a transmitter 302 or a receiver 306 to shape or direct an antenna beam (e.g., a transmit beam or a receive beam) along a spatial path between the transmitter 302 and the receiver 306. Beamforming can be achieved by combining signals transmitted via antennas 304 or 308 (e.g., antenna elements of an antenna array) so that some of the signals experience constructive interference and other signals experience destructive interference. In order to produce the desired constructive / destructive interference, the transmitter 302 or the receiver 306 can apply amplitude and / or phase offsets to the signals sent or received from the antenna elements 304 or 308 associated with the transmitter 302 or the receiver 306. In some examples, antenna elements can be mapped to antenna ports to generate beams. Here, the term antenna port refers to a logical port (e.g., a beam) through which a signal (e.g., a data stream or layer) can be sent. In the example of a base station, the antenna array may include 128 antenna elements (eg, within a 16x8 array), which may be mapped to 32 antenna ports by an 8x1 combiner.

[0096] To facilitate transmitting an SRS from, for example, a transmitter 302 to a receiver 306 using an uplink beam, each of the transmitter 302 and the receiver 306 may include a respective SRS manager 312a and 312b configured to utilize an SRS configuration for an SRS resource set including SRS resources associated with a plurality of TRPs. For example, the SRS manager 312b in the receiver 306 may be configured to generate an SRS configuration and provide the SRS configuration to the transmitter 302. In addition, the SRS manager 312a in the transmitter 302 may be configured to utilize the SRS configuration to generate a plurality of SRSs for transmitting to a plurality of receivers 306, one of which is located at a plurality of TRPs. Figure 3 ) for transmission.

[0097] In 5G New Radio (NR) systems (especially for systems above 6 GHz or mmWave), beamformed signals can be used for most downlink channels (including the Physical Downlink Control Channel (PDCCH) and the Physical Downlink Shared Channel (PDSCH)). In addition, broadcast control information (such as SSB, Slot Format Indicator (SFI), and paging information) can be sent in a beam scanning manner so that all scheduled entities (UEs) in the coverage area of ​​the Transmit Reception Point (TRP) (e.g., gNB) can receive the broadcast control information. In addition, for UEs configured with beamforming antenna arrays, beamformed signals can also be used for uplink channels (including the Physical Uplink Control Channel (PUCCH) and the Physical Uplink Shared Channel (PUSCH)). However, it should be understood that beamformed signals can also be used by enhanced mobile broadband (eMBB) gNBs for systems below 6 GHz.

[0098] A base station (e.g., a gNB) is typically capable of using transmit beams (e.g., downlink transmit beams) of different beam widths to communicate with a UE. For example, a base station may be configured to utilize a wider beam when communicating with a UE in motion and a narrower beam when communicating with a fixed UE. The UE may also be configured to utilize one or more downlink receive beams to receive signals from the base station. In some examples, in order to select one or more downlink transmit beams and one or more downlink receive beams for communication with the UE, the base station may send a reference signal, such as an SSB or a CSI-RS, on each of the multiple downlink transmit beams in a beam scanning manner. The UE may measure a reference signal received power (RSRP) on each of the downlink transmit beams using one or more downlink receive beams on the UE, and send a layer 1 (L1) measurement report indicating the RSRP of one or more of the measured downlink transmit beams to the base station. The base station may then select one or more serving downlink beams (e.g., a downlink transmit beam and a downlink receive beam) for communication with the UE based on the L1 measurement report. The resulting selected downlink transmit beam and downlink receive beam may form a downlink beam pair link. In other examples, when the channel is reciprocal, the base station may derive a specific downlink beam to communicate with the UE based on uplink measurements of one or more uplink reference signals, such as a sounding reference signal (SRS).

[0099] Similarly, an uplink beam (e.g., an uplink transmit beam at a UE and an uplink receive beam at a base station) may be selected by measuring the RSRP of a received uplink reference signal (e.g., SRS) or a downlink reference signal (e.g., SSB or CSI-RS) during uplink or downlink beam scanning. For example, a base station may determine an uplink beam by uplink beam management via SRS beam scanning and measurements at the base station or by downlink beam management via SSB / CSI-RS beam scanning and measurements at the UE. When uplink beam management is implemented, the selected uplink beam may be indicated by a selected SRS resource identifier (SRI), or when downlink beam management is implemented, the selected uplink beam may be indicated by selecting an SSB / CSI-RS resource. For example, the selected SSB / CSI-RS resource may have a spatial relationship with a selected uplink transmit beam (e.g., an uplink transmit beam for PUCCH, SRS, and / or PUSCH). The resulting selected uplink transmit beam and uplink receive beam may form an uplink beam pair link.

[0100] Figure 4 4 is a diagram illustrating communication between a base station 404 and a UE 402 using beamformed signals according to some aspects. The base station 404 may be a Figure 1 and / or any of the base stations (e.g., gNBs) or scheduling entities shown in 2, and UE 402 may be in Figure 1 and / or any one of the UEs or scheduled entities shown in 2.

[0101] exist Figure 4 In the example shown in , the base station 404 is configured to generate multiple beams 406a-406h, each beam being associated with a different beam direction. In addition, the UE 402 is configured to generate multiple beams 408a-408e, each beam being associated with a different beam direction. The base station 404 and the UE 402 can use a downlink beam management scheme and / or an uplink beam management scheme to select one or more beams 406a-406h on the base station 404 and one or more beams 408a-408e on the UE 402 for transmitting uplink signals and downlink signals therebetween.

[0102] In an example of a downlink beam management scheme for selecting a downlink beam, the base station 404 may be configured to scan or transmit on each of a plurality of downlink transmit beams 406a-406h during one or more synchronization slots. For example, the base station 404 may transmit a reference signal, such as an SSB or a CSI-RS, on each beam in a different beam direction during a synchronization slot. The transmission of the beam reference signal may occur periodically (e.g., as configured by the gNB via radio resource control (RRC) signaling), semi-persistently (e.g., as configured by the gNB via RRC signaling and activated / deactivated via medium access control-control element (MAC-CE) signaling), or aperiodically (e.g., as triggered by the gNB via downlink control information (DCI)). It should be noted that while some beams are shown as being adjacent to each other, this arrangement may be different in different aspects. For example, the downlink transmit beams 406a-406h transmitted during the same symbol may not be adjacent to each other. In some examples, base station 404 may transmit more or fewer beams distributed in all directions (e.g., 360 degrees).

[0103] In addition, the UE 402 is configured to receive downlink beam reference signals on multiple downlink receive beams 408a-408e. In some examples, the UE 402 searches for and identifies each of the downlink transmit beams 406a-406h based on the beam reference signals. The UE 402 then performs beam measurements (e.g., RSRP, SINR, RSRQ, etc.) on the beam reference signals on each of the downlink receive beams 408a-408e to determine the corresponding beam quality of each of the downlink transmit beams 406a-406h as measured on each of the downlink receive beams 408a-408e.

[0104] The UE 402 may generate and send an L1 measurement report to the base station 404, the L1 measurement report including corresponding beam indices (beam identifiers (IDs)) and beam measurements for one or more of the downlink transmit beams 406a-406h on one or more of the downlink receive beams 408a-408e. The base station 404 may then select one or more downlink transmit beams on which to send unicast downlink control information and / or user data traffic to the UE 402. In some examples, the selected downlink transmit beam has the highest gain from the beam measurement report. In some examples, the UE 402 may also identify the downlink transmit beam selected by the base station based on the beam measurement. The transmission of the beam measurement report may occur periodically (e.g., as configured by the gNB via RRC signaling), semi-persistently (e.g., as configured by the gNB via RRC signaling and activated / deactivated via MAC-CE signaling), or aperiodically (e.g., as triggered by the gNB via DCI).

[0105] The base station 404 or the UE 402 may also select a corresponding downlink receive beam on the UE 402 for each selected serving downlink transmit beam to form a corresponding downlink beam pair link (BPL) for each selected serving downlink transmit beam. For example, the UE 402 may utilize beam measurement to select a corresponding downlink receive beam for each serving downlink transmit beam. In some examples, the selected downlink receive beam to be paired with a particular downlink transmit beam may have the highest gain for the particular downlink transmit beam.

[0106] In one example, a single downlink transmit beam (e.g., beam 406d) on the base station 404 and a single downlink receive beam (e.g., beam 408c) on the UE may form a single downlink BPL for communication between the base station 404 and the UE 402. In another example, multiple downlink transmit beams (e.g., beams 406c, 406d, and 406e) on the base station 404 and a single downlink receive beam (e.g., beam 408c) on the UE 402 may form respective downlink BPLs for communication between the base station 404 and the UE 402. In another example, multiple downlink transmit beams (e.g., beams 406c, 406d, and 406e) on the base station 404 and multiple downlink receive beams (e.g., beams 408c and 408d) on the UE 402 may form multiple downlink BPLs for communication between the base station 404 and the UE 402. In this example, the first downlink BPL may include a downlink transmit beam 406c and a downlink receive beam 408c, the second downlink BPL may include a downlink transmit beam 408d and a downlink receive beam 408c, and the third downlink BPL includes a downlink transmit beam 408e and a downlink receive beam 408d.

[0107] When the channel is reciprocal, the above-described downlink beam management scheme may also be used to select one or more uplink BPLs for uplink communication from UE 402 to base station 404. For example, the downlink BPL formed by beams 406d and 408e may also be used as an uplink BPL. Here, beam 408c is used as an uplink transmit beam, and beam 406d is used as an uplink receive beam.

[0108] In an example of an uplink beam management scheme, the UE 402 may be configured to scan or transmit on each of a plurality of uplink transmit beams 408a-408e. For example, the UE 402 may transmit an SRS on each beam in different beam directions. In addition, the base station 404 may be configured to receive an uplink beam reference signal on a plurality of uplink receive beams 406a-406h. In some examples, the base station 404 searches for and identifies each of the uplink transmit beams 408a-408e based on the beam reference signal. The base station 404 then performs beam measurements (e.g., RSRP, SINR, RSRQ, etc.) on the beam reference signal on each of the uplink receive beams 406a-406h to determine the corresponding beam quality of each of the uplink transmit beams 408a-408e as measured on each of the uplink receive beams 406-406h.

[0109] The base station 404 may then select one or more uplink transmit beams on which the UE 402 will send unicast downlink control information and / or user data traffic to the base station 404. In some examples, the selected uplink transmit beam has the highest gain. The base station 404 may also select a corresponding uplink receive beam on the base station 404 for each selected serving uplink transmit beam to form a corresponding uplink beam pair link (BPL) for each selected uplink transmit beam. For example, the base station 404 may utilize uplink beam measurements to select a corresponding uplink receive beam for each serving uplink transmit beam. In some examples, the selected uplink receive beam to be paired with a particular uplink transmit beam may have the highest gain for that particular uplink transmit beam.

[0110] The base station 404 may then notify the UE 402 of the selected uplink transmit beam. For example, the base station 404 may provide an SRS resource identifier (SRI) identifying the SRS transmitted on the selected uplink transmit beam. In some examples, the base station 404 may apply each selected uplink transmit beam (and corresponding uplink receive beam) to an uplink signal (e.g., PUCCH, PUSCH, etc.) and send a corresponding SRI associated with the selected uplink transmit beam applied to each uplink signal to the UE 402. When the channel is reciprocal, the above-described uplink beam management scheme may also be used to select one or more downlink BPLs for downlink communication from the base station 404 to the UE 402. For example, an uplink BPL may also be used as a downlink BPL.

[0111] To facilitate sending an SRS from UE 402 to base station 404 using an uplink beam, each of UE 402 and base station 406 may include respective SRS managers 410 and 412, respectively, configured to utilize an SRS configuration for an SRS resource set that includes SRS resources associated with multiple TRPs (e.g., base station 404 and at least one other base station or TRP). For example, SRS manager 412 may be configured to generate an SRS configuration and provide the SRS configuration to UE 402. In addition, SRS manager 410 may be configured to utilize the SRS configuration to generate multiple SRSs for transmission toward base station 404 and at least one other base station or TRP.

[0112] In some examples, the SRS manager 410 can be configured to send SRS resources based on a quasi co-location (QCL) association (as indicated in the SRS configuration) with another reference signal (such as an SSB, a CSI-RS, or another SRS). For example, the SRS configuration can indicate a QCL association between the SRS resource and a particular SSB beam, a CSI-RS beam, or an SRS beam. As an example, the SRS resource can have a QCL association with beam 406d, which can be, for example, a CSI-RS beam. Therefore, based on the QCL association (e.g., with CSI-RS beam 406d), the SRS manager 410 can use the same spatial domain filter used to receive the indicated reference signal (e.g., CSI-RS beam 406d) to send the SRS. In one example, the SRS manager 410 can send the SRS on beam 408c based on the QCL association with CSI-RS beam 406d.

[0113] Figure 5A and 5B 5 is a diagram illustrating an example of sounding reference signal (SRS) resources 502a and 502b according to some aspects. The SRS resources 502a and 502b are shown as being located within a portion of a resource grid 500 including a plurality of REs 508. In the time domain, the SRS resources may include a plurality of consecutive OFDM symbols N selected from the set consisting of {1, 2, 4} symb Therefore, the SRS resource can occupy 1, 2, or 4 OFDM symbols. Figure 5A In the example shown in FIG. , the SRS resource 502a includes one OFDM symbol, while Figure 5B In the example shown in , the SRS resource 502b includes two OFDM symbols. In addition, the SRS resource can be located within the last six symbols of the time slot. Therefore, the starting symbol of the SRS resource can be specified as a symbol number offset from the last symbol of the time slot. For example, the starting symbol I offset can be selected from the set consisting of {0,1,2,3,4,5}. Figure 5A In the example shown in FIG. 5 , the start symbol 506a may be indicated as I offset =1, and Figure 5B In the example shown in FIG. 5 , the start symbol 506 b may be indicated as I offset =3.

[0114] In the frequency domain, each SRS resource 502a and 502b may occupy multiple RBs m. SRS In some examples, the number of RBs can be 1≤m SRS ≤272. In addition, each SRS resource 502a and 502b may have a transmission comb structure k TC, so that every N subcarriers transmit SRS, where N = 2 or 4. Therefore, the transmission comb structure k TC can be selected from the set consisting of {2,4}. Figure 5A In the example shown in FIG. 1 , the SRS resource 502 a has a transmission comb structure 504 a of 2, while Figure 5B In the example shown in , the SRS resource 502b has a transmission comb structure 504b of 4. In some examples, an SRS resource (eg, SRS resource 502b) that occupies more than one symbol may be used to transmit a single SRS or one or more repetitions of an SRS.

[0115] Furthermore, each SRS resource 502a and 502b may include up to four antenna ports 510, which may be interleaved, for example, in the frequency domain. Figure 5A and 5B In the example shown in , multiple antenna ports 510 are shown, each antenna port is used to communicate on a corresponding beam 512. Figure 5A and 5B In the example shown in , each antenna port 510 refers to a logical port (e.g., beam 512) through which SRS can be transmitted. In one example, the UE may include an antenna array having multiple antenna elements, which may be mapped to the antenna port 510 via a combiner. Figure 5A and 5B The number of antenna ports 510 shown in FIG. 5 is exemplary only, and the present disclosure is not limited to any number of antenna ports. Figure 5A As shown, SRS resource 502a includes two antenna ports in antenna ports 510, each antenna port being associated with transmission of SRS on a corresponding beam 512. Figure 5B As shown, SRS resource 504 b includes three of antenna ports 510 , each antenna port being associated with transmission of an SRS on a corresponding beam 512 .

[0116] Fig. 6A , 6B6C are diagrams illustrating exemplary SRS configurations 600a-600c for SRS resource sets 602a-602c, each of which includes SRS resources 604a-604f, according to some aspects. An SRS resource set may include one or more SRS resources. For example, SRS resource set 602a (SRS resource set 0) includes SRS resources 604a and 604b (SRS resource 0.0 and SRS resource 0.1), SRS resource set 602b (SRS resource set 1) includes SRS resource 604c (SRS resource 1.0), and SRS resource set 602c (SRS resource set 2) includes SRS resource sets 604d, 604e, and 604f (SRS resource 2.0, SRS resource 2.1, and SRS resource 2.2).

[0117] like Figures 6A-6C As shown, multiple SRS resource sets 602a-602c can be configured for the UE. In addition, each SRS resource set 602a-602c can be configured as periodic, aperiodic or semi-persistent, so that each SRS resource in the corresponding SRS resource set is periodic, aperiodic or semi-persistent. For example, SRS resources 604a and 604b in SRS resource set 602a can be periodic SRS resources, SRS resource 604c in SRS resource set 602b can be aperiodic SRS resource, and SRS resources 604d-604f in SRS resource set 602c can be semi-persistent SRS resources.

[0118] Each SRS resource 604a-604f includes a set of SRS resource parameters that configure the SRS resource. For example, the SRS resource parameters may include a port set (eg, uplink beam), a number of consecutive symbols (N), and a symb ), time domain allocation (I offset ), repeat, transmission comb structure (k TC ), bandwidth (m SRS ) and other appropriate parameters. Each SRS may also be quasi-co-located (QCL) with another reference signal (such as SSB, CSI-RS, or another SRS). Therefore, based on the QCL association (e.g., with the SSB beam, CSI-RS beam, or SRS beam), the SRS resource may be sent using the same spatial domain filter used to receive / send the indicated reference signal (e.g., SSB beam, CSI-RS beam, or SRS beam).

[0119] The corresponding set of SRS resource parameters for each SRS resource in the SRS resources in a particular SRS resource set together form the SRS resource set parameters for the SRS resource set. In addition, the SRS resource set itself may also include additional SRS resource set parameters. For example, the SRS resource set parameters for the aperiodic SRS resource set 602b may also include a non-periodic trigger state (e.g., code point) for the aperiodic SRS resource set 602b (e.g., up to three trigger states are possible, each trigger state maps to an aperiodic SRS resource set), a time slot offset between the time slot of the DCI that triggers the aperiodic SRS resource and the transmission of the SRS (e.g., the SRS is transmitted k time slots after the time slot carrying the DCI containing the trigger state), and a CSI-RS resource identifier (CRI) for the precoder estimate of the aperiodic SRS associated with the aperiodic SRS resource set 602b. As another example, the SRS configuration for the periodic SRS resource set 602a or the semi-persistent SRS resource set 602c may indicate the period of the SRS resource (eg, the periodicity of the transmission of the SRS). The corresponding SRS resource set parameters then collectively form the SRS configurations 600a-600c of the corresponding SRS resource sets 602a-602c.

[0120] A radio access network (RAN) entity (e.g., a base station, which may be a TRP or include multiple TRPs in an RRH configuration) may semi-statically configure a UE with one or more SRS resource sets 602a-602c via, for example, radio resource control (RRC) signaling. In some examples, the RAN entity may send an RRC message including an RRC configuration (e.g., an RRC configuration information element (IE)) indicating an SRS configuration for a particular SRS resource set.

[0121] For example, the RAN entity may semi-statically configure the UE with one or more periodic SRS resource sets 602a, which the UE may utilize to generate a periodic SRS and send it to the RAN entity. As another example, the RAN entity may semi-statically configure the UE with one or more aperiodic SRS resource sets 602b and corresponding triggering states. The RAN entity may then use DCI to trigger the aperiodic SRS resource set 602b. As another example, the RAN entity may semi-statically configure the UE with one or more semi-persistent SRS resource sets 602c. The RAN entity may then use a medium access control (MAC) control element (MAC-CE) to activate or deactivate the semi-persistent SRS resource set 602c.

[0122] Fig. 7A704a and 704b for wireless communication with a UE 702. Each TRP 704a and 704b can be, for example, a base station (e.g., a gNB) or a remote radio head (RRH) of a base station. In some examples, the TRPs 704a and 704b can belong to the same cell (e.g., having the same physical cell identifier (PCI)) or to different cells (e.g., each having a different corresponding PCI). For example, each TRP 704a and 704b can correspond to a TRP in a cell. Figure 1 , 3 and / or any one of the base stations, RRHs or scheduling entities shown in 4. UE 702 may correspond to Figure 1 , 3 and / or any of the UEs or scheduled entities shown in 4. In some examples, UE 702 can be a high-end UE, a low-end UE, or a UE with reduced capabilities.

[0123] Fifth generation (5G) wireless communication networks, such as new radio (NR) wireless communication networks, support communications between base stations and high-end UEs for a variety of different use cases, including, for example, enhanced mobile broadband (eMBB) and ultra-reliable and low-latency communications (URLLC). NR networks may also support communications between base stations and low-end UEs in massive machine type communications (mMTC) use cases. In some examples, LTE-M or narrowband Internet of Things (NB-IoT) technology may be used to meet the requirements of mMTC.

[0124] In addition to providing services to high-end UEs (e.g., via eMMB and / or URLLC) and low-end UEs (e.g., via mMTC), NR networks can also provide services to UEs with reduced capabilities. The service requirements for UEs with reduced capabilities may be less than those for high-end UEs, but greater than those for low-end UEs. For example, use cases for UEs with reduced capabilities may include not only URLLC services with high requirements, but also low-end services to accommodate smaller form factors and longer battery life. Examples of UEs with reduced capabilities may include, but are not limited to, industrial wireless sensors, surveillance cameras, and wearable devices (e.g., smart watches, rings, electronic health-related devices, and medical monitoring devices). Typically, compared to high-end UEs, UEs with reduced capabilities have device designs including compact form factors and reduced complexity. For example, a UE with reduced capabilities may have a reduced number of transmit / receive antennas, a reduced device bandwidth (e.g., a reduced operating bandwidth of the UE), a relaxed processing time, and / or a relaxed processing capability. UEs with reduced capabilities can also be configured for power saving and battery life enhancement in delay-tolerant use cases.

[0125] UE 702 and TRPs 704a and 704b may also be configured to transmit beamformed signals therebetween using, for example, a millimeter wave carrier. To facilitate selection of one or more uplink beams for transmitting uplink signals from UE 702 to at least one of TRPs 704a and 704b, UE 702 may send an SRS to each of TRPs 704b and 704a to measure them. For example, based on the SRS measurements and feedback to UE 702, UE 702 may send subsequent uplink signals to the selected TRP (e.g., TRP 704a) on the selected uplink beam.

[0126] Transmission of SRS to multiple TRPs 704a and 704b may be utilized (e.g., if UE 702 is fixed with reduced capabilities), where TRP spatial diversity may help mitigate channel / path blocking or temporary shadowing (e.g., a temporary obstruction) of one TRP (e.g., TRP 704b). In addition, in the case where UE 702 is fixed and rotating (e.g., the UE is a video surveillance camera), UE 702 may be exposed to coverage of multiple TRPs 704a and 704b while rotating, and the UE may perform uplink beam selection between TRPs 704b and 704a. In addition, if UE 702 is configured for Layer 1 (L1) based cell mobility (where L1 messages rather than RRC messages are used for switching between TRPs 704a and 704b belonging to the same gNB), the UE may obtain SRS measurements from multiple TRPs 704b and 704a for switching and beam selection.

[0127] In some examples, UE 702 may be configured with a separate SRS resource set for each of TRPs 704a and 704b. In this example, to collect SRS measurements on both TRPs 704a and 704b, UE 702 may send a first SRS set to TRP 704a using a first SRS resource set configured for TRP 704a, and then subsequently send a second SRS set to TRP 704b using a different second SRS resource set configured for TRP 704b. Using two separate SRS resource sets (one for each TRP 704a and 704b), SRS measurements are delayed and resource usage is increased.

[0128] Thus, in various aspects of the present disclosure, a single SRS resource set may be configured for multiple TRPs 704a and 704b. The SRS resource set may include one or more SRS resources for each TRP 704a and 704b. Thus, SRS measurements may be obtained by both TRPs 704a and 704b in one time slot (e.g., one SRS beam scan). In some examples, at least one of the TRPs (e.g., TRP 704b, such as Fig. 7A 704a and 704b. The gNB 704b (or TRP 704a) may then send the SRS configuration of the multi-TRP SRS resource set to the UE 702 via, for example, RRC signaling. In addition, the UE 702 may also include an SRS manager 708, which is configured to generate multiple SRSs using the SRS configuration and send them to the multiple TRPs 704a and 704b on multiple uplink beams 706a, 706b, and 706c. For example, each of the TRPs 704a and 704b may receive at least one of the SRSs sent by the UE 702 according to the SRS configuration.

[0129] Figure 7B is a diagram illustrating an example of a multi-TRP SRS resource set 712 according to some aspects. Fig. 7A The figure shown in Figure 7B The multi-TRP SRS resource set 712 includes SRS resources 714a, 714b, and 714c associated with multiple TRPs 704a and 704b. SRS resource 714a may be configured for TRP 704a, while SRS resources 714b and 714c may be configured for TRP 704b. SRS resources 714a, 714b, and 714c may each be associated with a different beam direction (e.g., a different uplink beam). For example, Fig. 7A As shown, SRS resource 714a may be transmitted on beam 706a, SRS resource 714b may be transmitted on beam 706b, and SRS resource 714c may be transmitted on beam 706c.

[0130] exist Figure 7B In the example shown in FIG. 1 , the SRS resource 714a includes two subcarriers (eg, k TC =2) and a transmission comb structure 716a of two symbols, wherein the second symbol is a repetition of the first symbol. Fig. 7AAs shown, SRS resource 714a is repeated on beam 706a (eg, the same SRS is sent on beam 706a in two consecutive symbols). In addition, SRS resources 714b and 714c each include four subcarriers (eg, k TC =4) and a transmission comb structure 716b of a single symbol. Fig. 7A As shown, different SRSs corresponding to one of the SRS resources 714b and 714c are transmitted on beams 706b and 706c, respectively.

[0131] In some examples, the starting symbol of the SRS resource 714c may be configured with an offset of zero symbols (eg, I offset = 0), the starting symbol of the SRS resource 714b is configured with an offset of one symbol (eg, I offset =1), and the starting symbol of the SRS resource 714a may be configured with an offset of more than two symbols (eg, I offset >2). In some examples, the SRS resource 714a may be configured with an offset of three symbols (eg, offset =3) so that the SRS resources 714a, 714b, 714c can be located in consecutive symbols of the time slot. In other examples, the SRS resource 714a can be configured with an offset of more than three symbols (e.g., I offset >3) to provide a gap length 718 between the SRS resource 714a and the SRS resource 714b. The gap length 718 may include, for example, one or two symbols.

[0132] For example, when TRP 704a and TRP 704b belong to different respective timing advance groups (TAGs), gap length 718 may be configured. In this example, gap length 718 between respective SRS resources 714a and 714b / 714c associated with each of TRPs 704a and 704b, respectively, may be provided to accommodate different timing advances to be applied to SRS resources 714a and 714b due to different TAGs. In some examples, gap length 718 may be configured as part of the SRS resource configuration (e.g., by setting an I / O for SRS resource 714a). offset To accommodate the timing advance difference. For example, the gap length 718 can be set to accommodate the maximum timing advance difference that may occur between TAGs. In other examples, the gap length 718 can be signaled to the UE 702 separately based on different timing advance values ​​between TAGs or based on the possible maximum timing advance difference between TAGs.

[0133] In other examples, the gap length 718 may be configured by the UE 702 based on a difference between a first timing advance command associated with a first TAG including TRP 704a and a second timing advance command associated with a second TAG including TRP 704b. The first timing advance command may indicate a first timing advance to be applied by the UE 702 to an uplink signal sent to a TRP (including TRP 704a) in the first TAG. The second timing advance command may indicate a second timing advance to be applied by the UE 702 to an uplink signal sent to a TRP (including TRP 704b) in the second TAG. Each timing advance command may be, for example, sent to the UE 702 by a TRP within a corresponding TAG. It should be noted that when TRPs 704a and 704b belong to the same TAG, the gap length 718 may be zero so that the SRS resources 714a, 714b, and 714c are located on consecutive symbols within the time slot.

[0134] In other examples, the gap length 718 may be configured when the QCL association for the SRS resource 714a associated with the TRP 704a is different from the QCL association for the SRS resource 714b / 714c associated with the TRP 704b. For example, the SRS resource 714a may include a first QCL association (e.g., with an SSB beam, a CSI-RS beam, or an SRS beam), and the SRS resource 714b / 714c may include a second QCL association that is different from the first QCL association (e.g., with a different SSB beam, CSI-RS beam, or SRS beam). The gap length 718 may be configured to enable the UE 702 to switch the beam direction and spatial filter from the first QCL association to the second QCL association. In some examples, the gap length 718 may be determined based on the capabilities of the UE 702 (e.g., the amount of time required for the UE 702 to switch between QCL associations). For example, UE 702 may provide UE capabilities to the gNB (e.g., via one or more of TRPs 704a and 704b), and receive a UE-specific gap length 718 configured according to the UE capabilities from a TRP (e.g., TRP 704a or 704b). In other examples, the gap length 718 may be a common gap length 718 configured for all UEs (e.g., by a gNB associated with TRPs 704a and 704b), and an indication of the common gap length 718 may be received from one of TRPs 704a and 704b. For example, the preconfigured gap length 718 may be set to accommodate any UE capabilities.

[0135] It should be appreciated that in other configurations, the SRS resource set 712 may span multiple time slots and, therefore, the starting symbol for each of the SRS resources 714a, 714b, and 714c may be configured based on the specific time slot associated with each SRS resource 714a, 714b, and 714c.

[0136] Figure 8 804N is a signaling diagram illustrating an example of signaling between a UE 802 and multiple TRPs 804a...804N utilizing multiple TRPSRS resource sets according to some aspects. The UE 802 may correspond to Figure 1 , 3 , 4 and / or 7. In addition, the TRP (e.g., TRP-1 to TRP-N) may correspond to any of the UEs or scheduled entities shown in FIG. Figure 1 , 3 , 4 and / or 7. In some examples, TRPs 804a...804N may belong to the same cell or different cells (e.g., at least two of the TRPs may include different corresponding PCIs). In addition, TRPs 804a...804N may belong to the same TAG or different TAGs (e.g., at least two of the TRPs may belong to different corresponding TAGs).

[0137] At 806, a TRP (e.g., TRP 804a) may send an SRS configuration for a multi-TRP SRS resource set to UE 802. The multi-TRP SRS resource set may include a plurality of SRS resources associated with a plurality of TRPs 804a ... 804N. The multi-TRP SRS resource set may be, for example, an aperiodic SRS resource set, a periodic SRS resource set, or a semi-persistent SRS resource set. In some examples, a gap length may be configured between SRS resources associated with TRPs belonging to different TAGs or associated with different QCLs within the multi-TRP SRS resource set.

[0138] The SRS configuration may be configured, for example, by TRP 804a in coordination with other TRPs or by a base station (e.g., gNB) associated with TRP 804a…804N. In some examples, the SRS configuration may include a common SRS resource set parameter set for multiple TRPs 804a…804N. For example, the SRS configuration may configure a multi-TRP SRS resource set including one or more SRS resources, each SRS resource including the same (common) SRS resource parameters (e.g., transmission comb structure, port, number of symbols, repetition, etc.). In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each of the multiple TRPs 804a…804N. For example, the SRS configuration may include multiple TRP SRS configurations each associated with a corresponding TRP, wherein each TRP SRS configuration includes different corresponding SRS resource parameters. Each TRP SRS configuration may configure one or more SRS resources associated with a specific TRP. Therefore, each TRP SRS configuration includes SRS resource set parameters configured for a specific SRS resource for that TRP.

[0139] As an example, the SRS configuration may include a first TRP SRS configuration that configures one or more SRS resources associated with TRP-1 and a second TRP SRS configuration that configures one or more different SRS resources with different SRS resource parameters associated with TRP-2. Therefore, the SRS resource set parameters of the first TRP SRS configuration may be different from the SRS resource set parameters of the second TRP SRS configuration.

[0140] The SRS configuration may be provided to the UE 802 in a radio resource control (RRC) message. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC information element (IE)) that includes the SRS configuration. For example, the RRC configuration may include a sequence of TRP SRS configurations. In examples where the SRS configuration includes a common SRS resource set parameter set, the sequence may have a length of 1 (e.g., a single TRP SRS configuration including a common SRS resource set parameter). In other examples, the RRC message may include multiple RRC configurations (e.g., multiple RRC configuration IEs), each RRC configuration including one of the TRP SRS configurations.

[0141] At 808, TRP 804a may optionally send an activation / trigger for a multi-TRP SRS resource set. For example, TRP 804a may send a DCI that triggers an aperiodic multi-TRP SRS resource set or a MAC-CE that activates a semi-persistent multi-TRP-SRS resource set. In some examples, when the multi-TRP SRS resource set is a non-periodic SRS resource set, TRP 804a may send a DCI that includes a code point that triggers the multi-TRP SRS resource set. For example, when the SRS configuration includes a single RRC configuration (e.g., a single TRPSRS configuration), the code point may trigger the SRS configuration. In examples where the SRS configuration includes multiple RRC configurations (e.g., multiple TRPSRS configurations), the code point may trigger multiple TRP SRS configurations.

[0142] At 810a...810N, UE 802 may send multiple SRSs to TRPs 804a...804N according to the SRS configuration. For example, UE 802 may send one or more SRSs to each TRP 804a...804N, corresponding to multiple SRS resources configured for each TRP 804a...804N. In some examples, when a common SRS resource set parameter set is used, each SRS resource in the SRS resource set may be associated with all TRPs. For example, each TRP 804a...804N may receive all SRSs configured in the SRS resource set. In other examples, each SRS resource in the SRS resource set may be associated with a specific TRP.

[0143] Fig. 9 904N for power control of SRS resources according to some aspects. Figure 1 , 3 , 4, 7 and / or 8. In addition, the TRP (e.g., TRP-1 to TRP-N) may correspond to any of the UEs or scheduled entities shown in FIG. Figure 1 , 3 , 4, 7 and / or 8. In some examples, TRPs 904a...904N may belong to the same cell or different cells. In addition, TRPs 904a...904N may belong to the same TAG or different TAGs.

[0144] At 906, a TRP (e.g., TRP 904a) may send an SRS configuration for a multi-TRP SRS resource set to UE 902. The multi-TRP SRS resource set may include multiple SRS resources associated with TRPs 904a...904N. The multi-TRP SRS resource set may be, for example, an aperiodic SRS resource set, a periodic SRS resource set, or a semi-persistent SRS resource set. In some examples, a gap length may be configured between SRS resources associated with TRPs belonging to different TAGs or associated with different QCLs within a multi-TRP SRS resource set. In some examples, the SRS configuration may include a common SRS resource set parameter set for TRPs 904a...904N. In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each of TRPs 904a...904N. In some examples, the SRS configuration may be provided to UE 902 in an RRC message. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC configuration IE) that includes an SRS configuration. In other examples, the RRC message may include multiple RRC configurations (e.g., multiple RRC configuration IEs), each RRC configuration including a TRP SRS configuration associated with one of TRPs 904a...904N.

[0145] At 908a...908N, TRPs 904a...904N may send corresponding transmit power control (TPC) commands (TPC-1...TPC-N) to UE 902. In some examples, the TPC commands may be closed-loop TPC commands for use in determining a transmit power of a physical uplink control channel (PUSCH) sent to the corresponding TRPs 904a...904N. In other examples, the TPC commands may be closed-loop TPC commands for use in determining a transmit power of an SRS sent to the corresponding TRPs 904a...904N. For example, the TPC commands may be included in DCI formats 2_3.

[0146] At 910, TRP 904a may optionally send an activation / trigger for a multi-TRP SRS resource set. For example, TRP 904a may send a DCI that triggers an aperiodic multi-TRP SRS resource set or a MAC-CE that activates a semi-persistent multi-TRP SRS resource set. In some examples, when the multi-TRP SRS resource set is a non-periodic SRS resource set, TRP 904a may send a DCI that includes a code point that triggers the multi-TRP SRS resource set. For example, when the SRS configuration includes a single RRC configuration (e.g., a single TRPSRS configuration), the code point may trigger the SRS configuration. In an example where the SRS configuration includes multiple RRC configurations (e.g., multiple TRP SRS configurations), the code point may trigger multiple TRP SRS configurations.

[0147] At 912a...912N, UE 902 may send one or more SRSs to TRP 904a...904N using corresponding transmit powers (TP-1...TP-N) based on corresponding TPC commands (TPC-1...TPC-N) according to the SRS configuration. For example, UE 902 may send one or more SRSs to TRP 904a using a first transmit power (TP-1) based on TPC-1. In addition, UE 902 may send one or more SRSs to TRP 904N using an Nth transmit power (TP-N) based on TPC-N.

[0148] Fig.10 1004N for power control of SRS resources according to some aspects. Figure 1 , 3 , 4 and / or 7-9. In addition, TRPs (e.g., TRP-1 to TRP-N) may correspond to any of the UEs or scheduled entities shown in FIG. Figure 1 , 3 , 4 and / or any of the base stations, TRPs or scheduling entities shown in 7-9. In some examples, TRPs 1004a...1004N may belong to the same cell or different cells. In addition, TRPs 1004a...1004N may belong to the same TAG or different TAGs.

[0149] At 1006, a TRP (e.g., TRP 1004a) may send an SRS configuration for a multi-TRP SRS resource set to UE 1002. The multi-TRP SRS resource set may include multiple SRS resources associated with TRPs 1004a...1004N. The multi-TRP SRS resource set may be, for example, an aperiodic SRS resource set, a periodic SRS resource set, or a semi-persistent SRS resource set. In some examples, a gap length may be configured between SRS resources associated with TRPs belonging to different TAGs or associated with different QCLs within a multi-TRP SRS resource set. In some examples, the SRS configuration may include a common SRS resource set parameter set for TRPs 1004a...1004N. In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each of TRPs 1004a...1004N. In some examples, the SRS configuration may be provided to UE 1002 in an RRC message. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC configuration IE) that includes an SRS configuration. In other examples, the RRC message may include multiple RRC configurations (e.g., multiple RRC configuration IEs), each RRC configuration including a TRP SRS configuration associated with one of TRPs 1004a…1004N.

[0150] At 1008, TRP 1004a may send a transmit power control (TPC) command (TPC-1) to UE 1002. In some examples, the TPC command may be a closed-loop TPC command for use in determining a transmit power of a physical uplink control channel (PUSCH) sent to TRP 1004a. In other examples, the TPC command may be a closed-loop TPC command for use in determining a transmit power of an SRS sent to TRP 1004. For example, the TPC command may be included in DCI format 2_3.

[0151] At 1010, UE 1002 may apply the TPC command to each of the other TRPs (e.g., up to TRP 1004N). For example, the SRS resources configured in the multi-TRP SRS resource set may include a first SRS resource set associated with TRP 1004a and a second SRS resource set associated with TRP 1004N. UE 1002 may apply the TPC command received for the first SRS resource set to the second SRS resource set.

[0152] At 1012, TRP 1004a may optionally send an activation / trigger for a multiple TRP SRS resource set. For example, TRP 1004a may send a DCI that triggers an aperiodic multiple TRP SRS resource set or a MAC-CE that activates a semi-persistent multiple TRP SRS resource set. In some examples, when the multiple TRP SRS resource set is an aperiodic SRS resource set, TRP 1004a may send a DCI that includes a code point that triggers the multiple TRP SRS resource set. For example, when the SRS configuration includes a single RRC configuration (e.g., a single TRP SRS configuration), the code point may trigger the SRS configuration. In examples where the SRS configuration includes multiple RRC configurations (e.g., multiple TRP SRS configurations), the code point may trigger multiple TRP SRS configurations.

[0153] At 1014a ... 1014N, UE 1002 may transmit one or more SRSs to TRPs 1004a ... 1004N using a transmit power (TP-1) based on a TPC command (TPC-1) according to the SRS configuration. For example, UE 1002 may transmit one or more SRSs to TRP 1004a using a first transmit power (TP-1) based on TPC-1. In addition, UE 1002 may transmit one or more SRSs to TRP 1004N using a first transmit power (TP-1) based on TPC-1.

[0154] Fig.11 1 is a block diagram illustrating an example of a hardware implementation for an exemplary UE 1100 employing a processing system 1114. For example, the UE 1100 may be a Figure 1 , 3 and / or any one of the UEs or scheduled entities shown in any one or more of Figures 7-10.

[0155] UE 1100 may be implemented using a processing system 1114 that includes one or more processors 1104. Examples of processors 1104 include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform various functions described throughout the present disclosure. In various examples, UE 1100 may be configured to perform any one or more of the functions described herein. That is, processor 1104 as utilized in UE 1100 may be used to implement the following in conjunction with Fig.11 Any one or more of the processes described.

[0156] In some cases, the processor 1104 may be implemented via a baseband or modem chip, while in other implementations, the processor 1104 itself may include multiple devices that are distinct and different from the baseband or modem chip (e.g., in such scenarios that can work together to implement aspects discussed herein). And as mentioned above, various hardware arrangements and components outside of the baseband modem processor may be used in various implementations, including RF chains, power amplifiers, modulators, buffers, interleavers, adders / summers, etc.

[0157] In this example, the processing system 1114 can be implemented using a bus architecture, which is generally represented by a bus 1102. Depending on the specific application and overall design constraints of the processing system 1114, the bus 1102 may include any number of interconnecting buses and bridges. The bus 1102 communicatively couples various circuits including one or more processors (which are generally represented by processor 1104), memory 1105, and computer-readable media (which are generally represented by computer-readable media 1106). The bus 1102 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described. The bus interface 1108 provides an interface between the bus 1102 and the transceiver 1110. The transceiver 1110 provides a unit for communicating with various other devices on a transmission medium (e.g., an air interface). In some examples, the transceiver 1110 may include a phase shifter 1116 for digital and / or analog beamforming via one or more antenna arrays 1130. A user interface 1112 (eg, keypad, display, speaker, microphone, joystick) may also be provided.

[0158] The processor 1104 is responsible for managing the bus 1102 and general processing, including executing software stored on the computer-readable medium 1106. The software, when executed by the processor 1104, causes the processing system 1114 to perform the various functions described below for any particular device. The computer-readable medium 1106 and the memory 1105 may also be used to store data that is manipulated by the processor 1104 when executing the software.

[0159] One or more processors 1104 in the processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted to mean instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc. The software may reside on a computer-readable medium 1106.

[0160] Computer readable medium 1106 may be a non-transitory computer readable medium. For example, non-transitory computer readable media include magnetic storage devices (e.g., hard disks, floppy disks, tapes), optical disks (e.g., compact disks (CDs) or digital versatile disks (DVDs)), smart cards, flash memory devices (e.g., card, stick, or key drives), random access memory (RAM), read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), registers, removable disks, and any other suitable medium for storing software and / or instructions that can be accessed and read by a computer. Computer readable medium 1106 may be located in processing system 1114, outside of processing system 1114, or distributed among multiple entities including processing system 1114. Computer readable medium 1106 may be embodied in a computer program product. In some examples, computer readable medium 1106 may be part of memory 1105. For example, a computer program product may include a computer readable medium having packaging material. Those skilled in the art will recognize how to best implement the described functionality presented throughout this disclosure depending on the particular application and the overall design constraints imposed on the overall system.

[0161] In some aspects of the present disclosure, processor 1104 may include circuits configured for various functions. For example, processor 1104 may include communication and processing circuits 1142 configured to communicate with one or more radio access network (RAN) entities, such as one or more base stations (e.g., gNBs), one or more TRPs, and / or one or more scheduling entities. In some examples, communication and processing circuits 1142 may include one or more hardware components that provide a physical structure that performs processes associated with wireless communication (e.g., signal reception and / or signal transmission) and signal processing (e.g., processing received signals and / or processing signals for transmission).

[0162] In some examples, the communication and processing circuitry 1142 can be configured to receive and process downlink beamforming signals at millimeter wave frequencies or frequencies below 6 GHz via the transceiver 1110 and the antenna array 1130 (e.g., using the phase shifter 1116). In addition, the communication and processing circuitry 1142 can be configured to generate and transmit uplink beamforming signals at millimeter wave frequencies or frequencies below 6 GHz via the transceiver 1110 and the antenna array 1130 (e.g., using the phase shifter 1116).

[0163] The communication and processing circuit 1142 may also be configured to receive an SRS configuration 1120 for a multi-TRP SRS resource set from a TRP in a plurality of TRPs in communication with the UE 1100. The multi-TRP SRS resource set may include a plurality of SRS resources associated with the plurality of TRPs. The plurality of TRPs may be separate base stations or RRHs of the same base station. In some examples, the plurality of TRPs may be co-located or located at different geographic locations and may belong to the same cell or different cells.

[0164] The multiple TRP SRS resource sets may be, for example, a non-periodic SRS resource set, a periodic SRS resource set, or a semi-persistent SRS resource set. In some examples, the SRS configuration may be received within an RRC message. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC information element (IE)) that includes the SRS configuration. In other examples, the RRC message may include multiple RRC configurations (e.g., multiple RRC configuration IEs), each RRC configuration including one of multiple TRP SRS configurations, each TRP SRS configuration being associated with one of the TRPs, wherein the multiple TRP SRS configurations together form the SRS configuration. The communication and processing circuit 1142 may also be configured to store the SRS configuration 1120, for example, in the memory 1105.

[0165] The communication and processing circuit 1142 may also be configured to receive an activation / trigger for a multiple TRP SRS resource set. For example, the communication and processing circuit 1142 may receive a DCI that triggers an aperiodic multiple TRP SRS resource set or a MAC-CE that activates a semi-persistent multiple TRP SRS resource set. In some examples, the communication and processing circuit 1142 may be configured to receive a DCI that includes a code point that triggers an SRS configuration (e.g., when the SRS configuration includes a single RRC configuration) or a code point that triggers each TRP SRS configuration in multiple TRP SRS configurations (e.g., when the SRS configuration includes multiple RRC configurations).

[0166] The communication and processing circuit 1142 may also be configured to receive one or more closed-loop TPC commands 1122. In some examples, the communication and processing circuit 1142 may receive a TPC command from each of a plurality of TRPs. In other examples, the communication and processing circuit 1142 may receive a TPC command from one of the TRPs. The TPC command may be used for a PUSCH transmission or an SRS transmission. For example, a TPC command for an SRS may be received in a DCI format 2_3. In addition, the communication and processing circuit 1142 may be configured to receive one or more timing advance commands from a TRP.

[0167] The communication and processing circuit 1142 may also be configured to send one or more SRSs to multiple TRPs according to the SRS configuration. In some examples, the communication and processing circuit 1142 may be configured to control the power supply 1140 to generate the SRS at a corresponding transmit power based on the TPC command. The communication and processing circuit 1142 may also be configured to execute the communication and processing software 1152 stored in the computer-readable medium 1106 to implement one or more of the functions described herein.

[0168] The processor 1104 may also include an SRS manager circuit 1144, which is configured to process the SRS configuration 1120. In some examples, the SRS configuration may include a common SRS resource set parameter set for multiple TRPs. For example, a multi-TRP SRS resource set may include one or more SRS resources, each SRS resource including the same (common) SRS resource parameters (e.g., transmission comb structure, port, number of symbols, repetition, etc.). In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each TRP in the multiple TRPs. For example, the SRS configuration may include multiple TRP SRS configurations each associated with a corresponding TRP, wherein each TRP SRS configuration includes different corresponding SRS resource parameters. Each TRP SRS configuration may configure one or more SRS resources associated with a specific TRP. Therefore, each TRP SRS configuration may include SRS resource set parameters configured for a specific SRS resource for that TRP.

[0169] In some examples, when each TRP belongs to the same TAG and the QCL associations for the SRS resources configured for each TRP are the same, the SRS resources associated with multiple TRPs can be located within consecutive symbols of the time slot. In some examples, two TRPs in the TRP may belong to different TAGs, or the QCL associations for the SRS resources configured for the two TRPs in the TRP may be different. In this example, the SRS manager circuit 1144 can be configured to provide a gap length of one or more symbols between the SRS resources associated with each TRP in the TRP. For example, the SRS manager circuit 1144 can be configured to provide a gap length between a first set of SRS resources associated with a first TRP and a second set of SRS resources associated with a second TRP.

[0170] In some examples, when each of the TRPs belongs to a different TAG, the gap length between the corresponding SRS resources associated with each of the TRPs can accommodate the different timing advances to be applied to the SRS resources. In some examples, the SRS manager circuit 1144 can configure the gap length as a function of the different timing advance commands received for each of the TAGs. In other examples, the SRS manager circuit 1144 can receive the gap length from the TRP. For example, the gap length can be set to accommodate the maximum timing advance difference that may occur between the TAGs. In some examples, the gap length can be received as part of the SRS resource configuration (e.g., within the SRS configuration 1120). In other examples, the gap length can be received separately from the SRS configuration.

[0171] In some examples, when the QCL associations for the SRS resources associated with each TRP are different, the gap length between the corresponding SRS resources can enable the SRS manager circuit 1144 to switch the beam direction and spatial filter of the antenna array 1130 and the phase shifter 1116 from the first QCL association to the second QCL association. In some examples, the SRS manager circuit 1144 can determine the gap length based on the capabilities of the UE 1100 (e.g., the amount of time required for the SRS manager circuit 1144 to switch between QCL associations). In other examples, the communication and processing circuit 1142 can send UE capabilities to a base station associated with one or more TRPs, and receive a UE-specific gap length configured according to the UE capabilities from the base station. In other examples, the gap length received from the base station can be a common gap length configured for all UEs, and the communication and processing circuit 1142 can be configured to receive an indication of the common gap length from one of the TRPs. The gap length can be received within the SRS configuration 1120 or separately from the SRS configuration.

[0172] The SRS manager circuit 1144 may also be configured to generate an SRS based on the SRS configuration 1120, and provide the SRS to the communication and processing circuit 1142 to transmit the SRS to multiple TRPs via the transceiver 1110. The SRS manager circuit 1144 may also be configured to determine a corresponding transmit power for each of the SRSs based on the TPC command 1122, and provide the corresponding transmit power for each of the SRSs to the communication and processing circuit 1142 to transmit the SRS at the appropriate transmit power. In some examples, the SRS manager circuit 1144 may be configured to apply a TPC command associated with a first set of SRS resources associated with a first TRP to a second set of SRS resources associated with a second TRP. The SRS manager circuit 1144 may also be configured to execute SRS manager software 1154 stored in the computer-readable medium 1106 to implement one or more of the functions described herein.

[0173] Fig.12 12 is a conceptual diagram illustrating an example of a hardware implementation for an exemplary RAN entity 1200 employing a processing system 1214. For example, the RAN entity 1200 may correspond to Figure 1 , 3 , 4 and / or any one or more of the base stations (e.g., gNBs), TRPs (e.g., combined TRPs and base stations in an RRH configuration), or other scheduling entities shown in any one or more of the figures 7-10.

[0174] According to various aspects of the present disclosure, an element or any portion of an element or any combination of elements may be implemented using a processing system 1214 that includes one or more processors 1204. The processing system 1214 may be used with Fig.11 The processing system 1114 shown in FIG. 1 is substantially the same as that shown in FIG. 1 , including a bus interface 1208, a bus 1202, a memory 1205, a processor 1204, and a computer-readable medium 1206. In addition, the RAN entity 1200 may include an optional user interface 1212 and a transceiver 1210, which are substantially similar to those described above in FIG. Fig.11 In some examples, the transceiver 1210 may include a phase shifter 1216 for digital and / or analog beamforming via one or more antenna arrays 1230. The processor 1204 as utilized in the RAN entity 1200 may be used to implement any one or more of the processes described below.

[0175] In some aspects of the present disclosure, the processor 1204 may include circuits configured for various functions. For example, the processor 1204 may include a resource assignment and scheduling circuit 1242 configured to generate, schedule, and modify resource assignments or grants of time-frequency resources (e.g., a set of one or more resource elements). For example, the resource assignment and scheduling circuit 1242 may schedule time-frequency resources within multiple time division duplex (TDD) and / or frequency division duplex (FDD) subframes, time slots, and / or mini-slots to carry user data traffic and / or control information to and / or from multiple UEs.

[0176] In some examples, the resource assignment and scheduling circuit 1242 may be configured to schedule resources for sending an SRS configuration for a multi-TRP SRS resource set to a user equipment (UE) communicating with the RAN entity 1200. The resource assignment and scheduling circuit 1242 may also be configured to schedule resources for receiving one or more SRSs from the UE according to the SRS configuration. The resource assignment and scheduling circuit 1242 may also be configured to schedule resources for sending a DCI that triggers an SRS configuration or a MAC-CE that activates an SRS configuration. In addition, the resource assignment and scheduling circuit 1242 may also be configured to schedule resources for sending a TPC command to the UE. The resource assignment and scheduling circuit 1242 may also be configured to execute resource assignment and scheduling software 1252 stored in the computer-readable medium 1206 to implement one or more of the functions described herein.

[0177] Processor 1204 may also include communication and processing circuitry 1244 configured to communicate with the UE. In some examples, communication and processing circuitry 1244 may include one or more hardware components that provide a physical structure that performs processes associated with wireless communication (e.g., signal reception and / or signal transmission) and signal processing (e.g., processing received signals and / or processing signals for transmission).

[0178] In some examples, the communication and processing circuitry 1244 can be configured to receive and process uplink beamforming signals at millimeter wave frequencies or frequencies below 6 GHz via the transceiver 1210 and the antenna array 1230 (e.g., using the phase shifter 1216). In addition, the communication and processing circuitry 1244 can be configured to generate and transmit uplink beamforming signals at millimeter wave frequencies or frequencies below 6 GHz via the transceiver 1210 and the antenna array 1230 (e.g., using the phase shifter 1216).

[0179] The communication and processing circuit 1244 may also be configured to send an SRS configuration 1220 for a multi-TRP SRS resource set to the UE. The multi-TRP SRS resource set may include multiple SRS resources associated with multiple TRPs. The multiple TRPs may be separate base stations or RRHs of the same base station. In the former example, the RAN entity 1200 may correspond to one of the base stations. In the latter example, the RAN entity 1200 may be coupled to each of the multiple TRPs. In some examples, the multiple TRPs may be co-located or located at different geographical locations and may belong to the same cell or different cells.

[0180] The multiple TRP SRS resource sets may be, for example, a non-periodic SRS resource set, a periodic SRS resource set, or a semi-persistent SRS resource set. In some examples, the SRS configuration may be sent within an RRC message. In some examples, the RRC message may include a single RRC configuration (e.g., a single RRC information element (IE)), the single RRC configuration including the SRS configuration. In other examples, the RRC message may include multiple RRC configurations (e.g., multiple RRC configuration IEs), each RRC configuration including a TRP SRS configuration in multiple TRP SRS configurations, each TRP SRS configuration being associated with one TRP in the TRP, wherein the multiple TRP SRS configurations together form the SRS configuration. The communication and processing circuit 1244 may also be configured to store the SRS configuration 1220, for example, in the memory 1205.

[0181] The communication and processing circuit 1244 may also be configured to send an activation / trigger for a multiple TRP SRS resource set. For example, the communication and processing circuit 1244 may send a DCI that triggers an aperiodic multiple TRP SRS resource set or a MAC-CE that activates a semi-persistent multiple TRP resource set. In some examples, the communication and processing circuit 1244 may be configured to send a DCI that includes a code point that triggers an SRS configuration (e.g., when the SRS configuration includes a single RRC configuration) or a code point that triggers each TRP SRS configuration in multiple TRP SRS configurations (e.g., when the SRS configuration includes multiple RRC configurations).

[0182] The communication and processing circuit 1244 may also be configured to send at least one closed-loop TPC command to the UE. The TPC command may be used for PUSCH transmission or SRS transmission. For example, the TPC command for SRS may be received in DCI format 2_3. In some examples, the TPC command is associated with one TRP in the TRP. In other examples, the TPC command may be applicable to each TRP in the TRP. In addition, the communication and processing circuit 1244 may be configured to send a timing advance command to the UE. The timing advance command indicates the timing advance to be applied by the UE to the uplink signal sent to the TRP within the TAG. Here, at least one TRP in the TRP in the TAG is associated with the RAN entity 1200 (e.g., a part of the RAN entity 1200). The communication and processing circuit 1244 may also be configured to receive one or more SRSs according to the SRS configuration. The communication and processing circuit 1244 may also be configured to execute the communication and processing software 1254 stored in the computer-readable medium 1206 to implement one or more of the functions described herein.

[0183] The processor 1204 may also include an SRS manager circuit 1246, which is configured to configure an SRS configuration for multiple TRP SRS resource sets for the UE. In some examples, the SRS configuration may include a common SRS resource set parameter set for multiple TRPs. For example, a multi-TRP SRS resource set may include one or more SRS resources, each SRS resource including the same (common) SRS resource parameters (e.g., transmission comb structure, port, number of symbols, repetition, etc.). In other examples, the SRS configuration may include a corresponding SRS resource set parameter set for each TRP in the multiple TRPs. For example, the SRS configuration may include multiple TRP SRS configurations each associated with a corresponding TRP, wherein each TRP SRS configuration includes different corresponding SRS resource parameters. Each TRP SRS configuration may configure one or more SRS resources associated with a specific TRP. Therefore, each TRP SRS configuration may include SRS resource set parameters configured for a specific SRS resource for the TRP.

[0184] In some examples, when each of the TRPs belongs to the same TAG and the QCL associations for the SRS resources configured for each of the TRPs are the same, the SRS manager circuit 1246 may configure the SRS resources associated with the multiple TRPs to be located within consecutive symbols of the time slot. In some examples, when two of the TRPs may belong to different TAGs or the QCL associations for the SRS resources configured for the two TRPs in the TRPs are different, the SRS manager circuit 1246 may be configured to determine a gap length of one or more symbols to be applied between the SRS resources associated with each of the TRPs. For example, the SRS manager circuit 1246 may be configured to determine a gap length to be applied between a first set of SRS resources associated with a first TRP and a second set of SRS resources associated with a second TRP.

[0185] In some examples, when the TRPs belong to different TAGs, the SRS manager circuit 1246 can set the gap length to accommodate the maximum timing advance difference that may occur between the TAGs. In other examples, when the QCL association between the SRS resources associated with each TRP in the TRP is different, the SRS manager circuit 1246 can set the gap length based on the capabilities of the UE or set the gap length to a common gap length configured for all UEs. In some examples, the SRS manager circuit 1246 can send an indication of the gap length as part of the SRS resource configuration (e.g., within the SRS configuration 1220) or separately from the SRS configuration via the communication and processing circuit 1244 and the transceiver 1210.

[0186] The SRS manager circuit 1246 may also receive and process each of the SRSs received from the UE to obtain corresponding measurements (e.g., RSRP, RSRQ, etc.) of each of the received SRSs for uplink beam management. The SRS manager circuit 1246 may also be configured to execute SRS manager software 1256 stored in the computer-readable medium 1206 to implement one or more of the functions described herein.

[0187] Fig.13 1 is a flow chart illustrating an example of a method 1300 for a UE to utilize multiple TRP SRS resource sets according to some aspects. As described below, some or all of the illustrated features may be omitted in certain implementations within the scope of the present disclosure, and some of the illustrated features may not be required for implementation of all aspects. In some examples, the method may be as described above and in Fig.11 The UE 1100 shown in FIG. 1 is executed by a processor or a processing system, or by any suitable means for performing the described functions.

[0188] At block 1302, the UE may receive an SRS configuration for a sounding reference signal (SRS) resource set, the SRS resource set comprising a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). In some examples, the SRS resource set comprises a periodic SRS resource set, a semi-persistent SRS resource set, or an aperiodic SRS resource set. In some examples, the SRS resource set is an aperiodic SRS resource set. In this example, the UE may also receive control information (e.g., DCI) comprising a code point that triggers an SRS configuration or a code point that triggers a plurality of TRP SRS configurations in the SRS configuration, wherein each TRP SRS configuration is associated with a corresponding TRP in the plurality of TRPs.

[0189] In some examples, each of the multiple TRPs includes the same PCI. In other examples, at least two of the TRPs in the multiple TRPs each include different corresponding PCIs. In some examples, the multiple TRPs belong to the same TAG. In this example, the SRS resources associated with the multiple TRPs can be located within consecutive symbols of the time slot. In other examples, at least two of the TRPs in the multiple TRPs belong to different corresponding TAGs.

[0190] In some examples, the SRS configuration includes a corresponding set of SRS resource set parameters for each TRP in the plurality of TRPs. In other examples, the SRS configuration includes a common set of SRS resource set parameters for the plurality of TRPs. For example, the above Fig.11 The communication and processing circuitry 1142 shown and described along with the SRS manager circuitry 1144, transceiver 1110, and antenna array 1130 may provide a means for receiving an SRS configuration.

[0191] At box 1304, the UE may optionally provide a gap length of at least one symbol between SRS resources associated with each TRP in a plurality of TRPs. For example, the SRS resources associated with the plurality of TRPs may include a first set of SRS resources associated with a first TAG and a second set of SRS resources associated with a second TAG. In this example, a gap length of at least one symbol may be provided between the first set of SRS resources and the second set of SRS resources. In some examples, the UE may configure the gap length based on a timing difference between a first timing advance command associated with the first TAG and a second timing advance command associated with the second TAG. In other examples, the UE may receive the gap length from a TRP in a plurality of TRPs.

[0192] In some examples, the SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP in the multiple TRPs and a second SRS resource set associated with a second TRP in the multiple TRPs. The first SRS resource set may include a first quasi-co-location (QCL) association, and the second SRS resource set may include a second QCL association that is different from the first QCL association. In this example, a gap length of one or more symbols may be provided between the first SRS resource set and the second SRS resource set. In some examples, the UE may determine the gap length based on the capabilities of the UE. In other examples, the UE may receive an indication of the gap length from a TRP in the multiple TRPs. For example, the above in conjunction with Fig.11 The SRS manager circuit 1144 shown and described may provide means for providing a gap length.

[0193] At block 1306, the UE may optionally receive at least one transmit power control (TPC) command applicable to the multiple TRPs from at least one of the TRPs. In some examples, the UE may receive multiple TPC commands, each TPC command associated with a TRP in the multiple TRPs. In other examples, the UE may receive a TPC command applicable to each TRP in the TRPs. For example, the SRS resources associated with the multiple TRPs may include a first set of SRS resources associated with a first TRP in the multiple TRPs and a second set of SRS resources associated with a second TRP in the multiple TRPs. The UE may receive a TPC command for the first set of SRS resources and apply the TPC command to the second set of SRS resources. For example, the above in conjunction with Fig.11 The communication and processing circuitry 1142 shown and described along with the SRS manager circuitry 1144, transceiver 1110, and antenna array 1130 may provide means for receiving TPC commands.

[0194] At block 1308, the UE may send multiple SRSs to the multiple TRPs according to the SRS configuration. In some examples, the UE may send the multiple SRSs to the multiple TRPs using a corresponding transmit power for each of the multiple TRPs based on multiple TPC commands. In other examples, the UE may send the multiple SRSs to the multiple TRPs using the same transmit power for each of the multiple SRSs based on a single TPC command. For example, the above with respect to Fig.11 The communication and processing circuitry 1142 shown and described along with the SRS manager circuitry 1144, transceiver 1110, power supply 1140, and antenna array 1130 may provide a means for transmitting multiple SRSs.

[0195] In one configuration, the UE 1100 includes a Fig.13In one aspect, the aforementioned units may be Fig.11 The processor 1104 shown in is configured to perform the functions recorded by the aforementioned units. In another aspect, the aforementioned units may be a circuit or any device configured to perform the functions recorded by the aforementioned units.

[0196] Of course, in the above examples, the circuits included in the processor 1104 are provided only as examples, and other units for performing the described functions may be included in various aspects of the present disclosure, including but not limited to instructions stored in the computer-readable storage medium 1106, or in Figure 1 , 3 , 4 and / or any of Figures 7-10 and using, for example, the present invention Fig.13 Any other suitable means or units of the described processes and / or algorithms.

[0197] Fig.14 1 is a flow chart illustrating an example of a method 1400 for a RAN entity to configure a multi-TRP SRS resource set according to some aspects. As described below, some or all of the illustrated features may be omitted in certain implementations within the scope of the present disclosure, and some of the illustrated features may not be required for implementation of all aspects. In some examples, the method may be as described above and in Fig.12 The RAN entity 1200 shown in FIG. 1 is executed by a processor or a processing system, or by any suitable unit for performing the described functions.

[0198] At block 1402, a RAN entity may configure a sounding reference signal (SRS) configuration for a user equipment (UE) resource set, the SRS resource set comprising a plurality of SRS resources associated with a plurality of transmit reception points (TRPs). In some examples, the SRS resource set comprises a periodic SRS resource set, a semi-persistent SRS resource set, or an aperiodic SRS resource set.

[0199] In some examples, each of the multiple TRPs includes the same PCI. In other examples, at least two of the TRPs in the multiple TRPs each include different corresponding PCIs. In some examples, the multiple TRPs belong to the same TAG. In this example, the SRS resources associated with the multiple TRPs can be located in consecutive symbols of the time slot. In other examples, at least two of the TRPs in the multiple TRPs belong to different corresponding TAGs. In some examples, the SRS configuration includes a corresponding set of SRS resource set parameters for each TRP in the multiple TRPs. In other examples, the SRS configuration includes a common set of SRS resource set parameters for the multiple TRPs. For example, the above in combination Fig.12The SRS manager circuit 1246 shown and described may provide means for configuring the SRS configuration.

[0200] At block 1404, the RAN entity may optionally determine a gap length of at least one symbol between SRS resources associated with each of the plurality of TRPs. In some examples, the SRS resources associated with the plurality of TRPs include a first set of SRS resources associated with a first TAG and a second set of SRS resources associated with a second TAG. In this example, the RAN entity may determine a gap length of at least one symbol to be applied between the first set of SRS resources and the second set of SRS resources. In some examples, the RAN entity may also send an indication of the gap length to the UE.

[0201] In some examples, the SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP in the multiple TRPs and a second SRS resource set associated with a second TRP in the multiple TRPs. The first SRS resource set may include a first quasi-co-location (QCL) association, and the second SRS resource set may include a second QCL association that is different from the first QCL association. In this example, the RAN entity may determine a gap length for at least one symbol to be applied between the first SRS resource set and the second SRS resource set. In some examples, the RAN entity may also send an indication of the gap length to the UE. In some examples, the RAN entity may determine the gap length based on the capabilities of the UE. For example, the above in combination Fig.12 The SRS manager circuit 1246 shown and described may provide means for determining the gap length.

[0202] At block 1406, the RAN entity may send an SRS configuration for an SRS resource set to the UE. In some examples, the SRS resource set is an aperiodic SRS resource set. In this example, the RAN entity may also send control information (e.g., DCI) that includes a code point that triggers the SRS configuration or a code point of multiple TRP SRS configurations that trigger the SRS configuration, wherein each TRP SRS configuration is associated with a corresponding TRP in the multiple TRPs. For example, the above in conjunction with Fig.12 The communication and processing circuitry 1244 shown and described along with the SRS manager circuitry 1246, transceiver 1210, and antenna array 1230 may provide a means for transmitting an SRS configuration.

[0203] At block 1408, the RAN entity may optionally send at least one TPC command applicable to the plurality of TRPs to the UE. Each TPC command in the at least one TPC command may be associated with a corresponding TRP in the plurality of TRPs. In other examples, the RAN entity may send a TPC command applicable to each TRP in the TRPs to the UE. For example, the above with respect to Fig.12 The communication and processing circuitry 1244 shown and described along with the SRS manager circuitry 1246, transceiver 1210, and antenna array 1230 may provide means for sending at least one TPC command to a UE.

[0204] At block 1410, the RAN entity may receive at least one SRS from the UE according to the SRS configuration. Fig.12 The communication and processing circuitry 1244, along with the SRS manager circuitry 1246, transceiver 1210, and antenna array 1230 shown and described may provide means for receiving at least one SRS.

[0205] Fig.15 1 is a flow chart of an exemplary method 1500 for a RAN entity to utilize multiple TRP SRS resource sets according to some aspects. As described below, some or all of the illustrated features may be omitted in certain implementations within the scope of the present disclosure, and some of the illustrated features may not be required for implementation of all aspects. In some examples, the method may be as described above and in Fig.12 The RAN entity 1200 shown in FIG. 1 is executed by a processor or a processing system, or by any suitable unit for performing the described functions.

[0206] At block 1502, a RAN entity may send to a user equipment (UE) a sounding reference signal (SRS) resource set for the UE. The SRS configuration may include a plurality of SRS resources associated with a plurality of transmit receive points (TRPs). In some examples, the plurality of TRPs each include the same PCI. In other examples, at least two of the TRPs in the plurality of TRPs each include a different corresponding PCI.

[0207] In some examples, multiple TRPs belong to the same TAG. In this example, the SRS resources associated with the multiple TRPs can be located in consecutive symbols of the time slot. In other examples, at least two TRPs in the multiple TRPs belong to different corresponding TAGs. In this example, the multiple SRS resources associated with the multiple TRPs can include a first SRS resource set associated with a first TAG and a second SRS resource set associated with a second TAG. The RAN entity can then also determine the gap length of at least one symbol between the first SRS resource set and the second SRS resource set, and send an indication of the gap length to the UE.

[0208] In some examples, the multiple SRS resources associated with the multiple TRPs may include a first SRS resource set associated with a first TRP in the multiple TRPs and a second SRS resource set associated with a second TRP in the multiple TRPs. The first SRS resource set may include a first quasi-co-location (QCL) association, and the second SRS resource set may include a second QCL association different from the first QCL association. In this example, the RAN entity may also determine a gap length of at least one symbol to be applied between the first SRS resource set and the second SRS resource set, and send an indication of the gap length to the UE. In some examples, the RAN entity may determine the gap length based on the capabilities of the UE.

[0209] In some examples, the SRS configuration includes at least one of the following: a corresponding SRS resource set parameter set for each TRP in a plurality of TRPs, or a common SRS resource set parameter set for a plurality of TRPs. In some examples, the RAN entity may send at least one TPC command to the UE. Each TPC command in the at least one TPC command may be associated with a corresponding TRP in the plurality of TRPs. In other examples, the RAN entity may send a TPC command applicable to each TRP in the TRPs to the UE.

[0210] In some examples, the SRS resource set is an aperiodic SRS resource set, and the SRS configuration includes multiple TRP SRS configurations, each TRP SRS configuration is associated with a corresponding TRP in the multiple TRPs. In this example, the RAN entity may also send control information (e.g., DCI) that includes a code point that triggers the multiple TRP SRS configurations. For example, the above Fig.12 The communication and processing circuitry 1244 shown and described along with the SRS manager circuitry 1246, transceiver 1210, and antenna array 1230 may provide a means for transmitting an SRS configuration.

[0211] At block 1504, the RAN entity may receive at least one SRS from the UE according to the SRS configuration. Fig.12 The communication and processing circuitry 1244, along with the SRS manager circuitry 1246, transceiver 1210, and antenna array 1230 shown and described may provide means for receiving at least one SRS.

[0212] In one configuration, the RAN entity 1200 includes a Fig.14 and / or Fig.15 In one aspect, the aforementioned units may be Fig.12 The processor 1204 shown in is configured to perform the functions recorded by the aforementioned units. In another aspect, the aforementioned units may be a circuit or any device configured to perform the functions recorded by the aforementioned units.

[0213] Of course, in the above examples, the circuits included in the processor 1204 are provided only as examples, and other units for performing the described functions may be included in various aspects of the present disclosure, including but not limited to instructions stored in the computer-readable storage medium 1206, or in Figure 1 , 3 , 4 and / or any of Figures 7-10 and using, for example, the present invention Fig.14 and / or any other suitable means or units of the processes and / or algorithms described in 15.

[0214] In a 5G NR network, a base station may be a converged base station (where the radio protocol stack is logically integrated within a single RAN entity) or a decomposed base station (e.g., a decomposed RAN entity) (where the radio protocol stack is logically split between a central unit (CU) and one or more distributed units (DUs)). The CU is responsible for the radio resource control (RRC), service data adaptation protocol (SDAP), and packet data convergence protocol (PDCP) layers that control the operation of one or more DUs. The DU is responsible for the radio link control (RLC), medium access control (MAC), and physical (PHY) layers. The CU may be implemented within an edge RAN node (which may be referred to as a donor node), while one or more DUs may be co-located with the CU and / or distributed in multiple RAN nodes that may be physically separated from each other.

[0215] In some examples, the above is combined with Fig.12 The RAN entity 1200 shown and described may be a decomposed base station. Fig.12The RAN entity 1200 shown in the figure may include a CU and optionally one or more DUs of a decomposed base station. Other DUs associated with the RAN entity 1200 may be distributed throughout the network. In this example, the DU may correspond to a TRP associated with the RAN entity. For example, a CU of a decomposed base station (e.g., within the RAN entity 1200) may configure an SRS resource set including SRS resources associated with multiple TRPs (e.g., DUs), and send an SRS configuration of the SRS resource set to one or more UEs communicating with the TRPs.

[0216] Fig.16 An example of a decomposed base station 1600 according to some aspects is shown. The decomposed base station 1600 includes a CU 1602 and one or more DUs (three DUs 1604a, 1604b, 1604c are shown for convenience). Each DU 1604a, 1604b, and 1604c supports the PHY, MAC, and RLC layers of the radio protocol stack. The CU 1602 supports higher layers, such as the PDCP and RRC layers. One of the DUs (e.g., DU 1604a) may be co-located with the CU 1602, while the other DUs 1604b and 1604c may be distributed throughout the network. CU 1602 and DU 1604a, 1604b, and 1604c are logically connected via an F1 interface, which utilizes an F1 application protocol (F1-AP) to transmit information between CU 1602 and each of DU 1604a, 1604b, and 1604c, and establishes a general tunneling protocol (GTP) tunnel between the DU and the CU for each radio bearer. In some examples, each of DU 1640a, 1640b, and 1640c may correspond to a TRP in a set of multiple TRPs, and CU 1602 may configure a single SRS resource set for multiple TRPs, as described herein.

[0217] For example, the decomposed base station 1600 can be used in an integrated access backhaul (IAB) network. In such an IAB network, the wireless spectrum can be used for both the access link and the backhaul link. In some examples, the wireless spectrum can utilize millimeter wave (mmWave) or sub-6 GHz carrier frequencies.

[0218] Fig.17 1700 is a schematic diagram showing an example of IAB node functionality within the IAB network 1700. Fig.17In the example shown in , the IAB node 1702 is shown as being coupled to the core network 1704 via a wired connection. The IAB node 1702 may be referred to herein as an IAB donor node, which may be, for example, an enhanced gNB including functionality for controlling the IAB network 1700. In some examples, the IAB donor node 1702 may include a central unit (CU) 1706 and a distributed unit (DU) 1708. The CU 1706 is configured to operate as a centralized network node (or central entity) within the IAB network 1700. For example, the CU 1706 may include radio resource control (RRC) layer functionality and packet data convergence protocol (PDCP) layer functionality to control / configure other nodes (e.g., IAB nodes and UEs) within the IAB network 1700. Thus, the CU 1706 may be configured to implement centralized mechanisms for handover decisions, topology changes, routing, bearer mapping, UE security, and other appropriate services.

[0219] The DU 1708 is configured to operate as a scheduling entity to schedule scheduled entities (e.g., other IAB nodes and UEs) of the IAB donor node 1702. For example, the DU 1708 of the IAB donor node 1702 may operate as a scheduling entity to schedule the IAB nodes 1710 and 1712 and the UEs 1714 and 1716. Thus, the DU 1708 of the IAB donor node 1702 may schedule communications with the IAB nodes 1710 and 1712 via corresponding backhaul links, and schedule communications with the UEs 1714 and 1716 via corresponding access links. In some examples, the DU 1708 may include radio link control (RLC), medium access control (MAC), and physical (PHY) layer functions to implement operations as a scheduling entity.

[0220] Each of the IAB nodes 1710 and 1712 may be configured as a layer 2 (L2) relay node, which includes a corresponding DU 1720 and a mobile termination (MT) unit 1718, so that each L2 relay IAB node 1710 and 1712 can operate as a scheduling entity and a scheduled entity. For example, the MT unit 1718 within each of the L2 relay IAB nodes 1710 and 1712 is configured to operate as a scheduled entity that can be scheduled by the IAB donor node 1702. Each MT unit 1718 within the L2 relay IAB nodes 1710 and 1712 also facilitates communication with the IAB donor node 1702 via a corresponding backhaul link. Additionally, the DU 1720 within each of the L2 relay IAB nodes 1710 and 1712 operates similarly to the DU 1708 within the IAB donor node 1702 to act as a scheduling entity to schedule one or more respective scheduled entities (eg, other IAB nodes and / or UEs) of the L2 relay IAB nodes 1710 and 1712 .

[0221] For example, the DU 1720 of the L2 relay IAB node 1712 acts as a scheduling entity to schedule communication with the UE 1722 via the access link, and the DU 1720 of the L2 relay IAB node 1710 acts as a scheduling entity to schedule communication with the MT unit 1718 of the L2 relay IAB nodes 1724 and 1726 via the corresponding backhaul link and communication with the UE 1728 via the access link. Each of the L2 relay IAB nodes 1724 and 1726 also includes a corresponding DU 1720, which acts as a scheduling entity to communicate with the corresponding UEs 1730 and 1732.

[0222] In some examples, each of the IAB nodes 1702, 1710, 1712, 1724, and 1726 can be interconnected via one or more wireless backhaul links. Each of the wireless backhaul links can utilize the same wireless spectrum (e.g., radio frequency (RF) spectrum) as the access link to backhaul access services to / from the remote network 1704. This can be referred to as wireless self-backhaul transmission. Such wireless self-backhaul transmission can enable highly dense small cell networks to be deployed quickly and easily. That is, the wireless spectrum used for communication between gNBs and UEs can be used for backhaul communications between any number of IAB nodes to form the IAB network 1700, without requiring each new gNB deployment to be equipped with its own hard-wired backhaul connection. In addition, some or all of the IAB nodes 1702, 1710, 1712, 1724, and 1726 can also be connected via a wired backhaul link (e.g., optical fiber, coaxial cable, Ethernet, copper wire, etc.) and / or a microwave backhaul link. Thus, the IAB network 1700 can support both wireline / microwave and wireless backhaul services.

[0223] exist Fig.17 In the network topology shown in , the IAB donor node 1702 in conjunction with each of the L2 relay IAB nodes 1710, 1712, 1724, and 1726 can together form a decomposed base station. The decomposed base station includes a CU 1706 and each of the DUs 1708 and 1720 controlled by the CU 1706. The CU / DU functional split in the decomposed base station can facilitate the implementation of time-critical services (such as scheduling, retransmission, segmentation, and other similar services) in the DU 1708 / 1720, while concentrating less time-critical services in the CU 1706. In addition, the CU / DU separation enables the termination of external interfaces in the CU 1706 instead of each DU, and further supports centralized termination of the PCDP to allow dual connectivity and switching between different DUs of the decomposed base station. It should be understood that the decomposed base station can be implemented in a network other than an IAB network, and the present disclosure is not limited to any particular type of network.

[0224] The following provides an overview of examples of the present disclosure.

[0225] Example 1: A method for performing wireless communications at a user equipment (UE) in a wireless communication network, the method comprising: receiving a sounding reference signal (SRS) configuration for an SRS resource set, wherein the SRS resource set comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs); and sending a plurality of SRSs to the plurality of TRPs according to the SRS configuration.

[0226] Example 2: A method according to Example 1, wherein each of the multiple TRPs includes the same physical cell identifier (PCI).

[0227] Example 3: A method according to Example 1, wherein at least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

[0228] Example 4: A method according to any one of Examples 1 to 3, wherein the multiple TRPs belong to the same timing advance group (TAG).

[0229] Example 5: A method according to any one of Examples 1 to 4, wherein the multiple SRS resources associated with the multiple TRPs are located within consecutive symbols of a time slot.

[0230] Example 6: A method according to any one of Examples 1 to 3, wherein at least two TRPs among the multiple TRPs belong to different corresponding TAGs.

[0231] Example 7: A method according to Example 6, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TAG and a second SRS resource set associated with a second TAG, and the method further includes: providing a gap length of at least one symbol between the first SRS resource set and the second SRS resource set.

[0232] Example 8: The method according to Example 7 further includes: configuring the gap length based on a timing difference between a first timing advance command associated with the first TAG and a second timing advance command associated with the second TAG.

[0233] Example 9: The method according to Example 7 also includes: receiving the gap length from a TRP among the multiple TRPs.

[0234] Example 10: A method according to any one of Examples 1 to 9, wherein the SRS resource set includes a periodic SRS resource set, a semi-persistent SRS resource set, or a non-periodic SRS resource set.

[0235] Example 11: A method according to any one of Examples 1 to 10, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP among the multiple TRPs and a second SRS resource set associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-location (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association, and the method further includes: providing a gap length of one or more symbols between the first SRS resource set and the second SRS resource set.

[0236] Example 12: The method according to Example 11 also includes: determining the gap length based on the capability of the UE.

[0237] Example 13: The method according to Example 11 also includes: receiving an indication of the gap length from a TRP among the multiple TRPs.

[0238] Example 14: A method according to any one of Examples 1 to 13, wherein the SRS configuration includes a corresponding set of SRS resource set parameters for each TRP in the multiple TRPs.

[0239] Example 15: A method according to any one of Examples 1 to 13, wherein the SRS configuration includes a common SRS resource set parameter set for the multiple TRPs.

[0240] Example 16: The method according to any one of Examples 1 to 15 further includes: receiving multiple transmit power control commands, each transmit power control command being associated with a TRP among the multiple TRPs; and wherein, sending the multiple SRSs to the multiple TRPs further includes: sending the multiple SRSs to the multiple TRPs using the corresponding transmit power for each TRP among the multiple TRPs based on the multiple transmit power control commands.

[0241] Example 17: The method according to any one of Examples 1 to 15 further includes: receiving a transmit power control command applicable to each TRP in the TRP; and wherein, sending the multiple SRSs to the multiple TRPs further includes: based on the transmit power control command, sending the multiple SRSs to the multiple TRPs using the same transmit power used for each SRS in the multiple SRSs.

[0242] Example 18: A method according to Example 17, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP among the multiple TRPs and a second SRS resource set associated with a second TRP among the multiple TRPs, and wherein the receiving the transmit power control command applicable to each TRP among the TRPs also includes: receiving the transmit power control command for the first SRS resource set; and applying the transmit power control command to the second SRS resource set.

[0243] Example 19: A method according to any one of Examples 1 to 18, wherein the SRS resource set includes a non-periodic SRS resource set, and the method further includes: receiving control information including a code point that triggers the SRS configuration.

[0244] Example 20: A method according to any one of Examples 1 to 18, wherein the SRS resource set includes a non-periodic SRS resource set, and the SRS configuration includes multiple TRP SRS configurations, each TRP SRS configuration is associated with a corresponding TRP in the multiple TRPs, and the method further includes: receiving control information including code points that trigger the multiple TRP SRS configurations.

[0245] Example 21: A method for performing wireless communications at a radio access network (RAN) entity in a wireless communication network, the method comprising: configuring a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE), wherein the SRS resource set comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs); sending the SRS configuration for the SRS resource set to the UE; and receiving at least one SRS from the UE based on the SRS configuration.

[0246] Example 22: A method according to Example 21, wherein each of the multiple TRPs includes the same physical cell identifier (PCI).

[0247] Example 23: A method according to Example 21, wherein at least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

[0248] Example 24: A method according to any one of Examples 21 to 23, wherein the RAN entity includes at least one TRP among the multiple TRPs.

[0249] Example 25: A method according to any one of Examples 21 to 24, wherein the multiple TRPs belong to the same timing advance group (TAG).

[0250] Example 26: A method according to any one of Examples 21 to 25, wherein the multiple SRS resources associated with the multiple TRPs are located within consecutive symbols of a time slot.

[0251] Example 27: A method according to any one of Examples 21 to 24, wherein at least two TRPs among the multiple TRPs belong to different corresponding TAGs.

[0252] Example 28: A method according to any one of Examples 21 to 24 or Example 27, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TAG and a second SRS resource set associated with a second TAG, and the method further includes: determining a gap length of at least one symbol to be applied between the first SRS resource set and the second SRS resource set; and sending an indication of the gap length to the UE.

[0253] Example 29: A method according to any one of Examples 21 to 28, wherein the SRS resource set includes a periodic SRS resource set, a semi-persistent SRS resource set, or a non-periodic SRS resource set.

[0254] Example 30: A method according to any one of Examples 21 to 29, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP among the multiple TRPs and a second SRS resource set associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-location (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association, and the method further includes: determining a gap length of at least one symbol to be applied between the first SRS resource set and the second SRS resource set; and sending an indication of the gap length to the UE.

[0255] Example 31: The method according to Example 30, wherein determining the gap further comprises: determining the gap length based on the capability of the UE.

[0256] Example 32: A method according to any one of Examples 21 to 31, wherein the SRS configuration includes a corresponding set of SRS resource parameters for each TRP in the multiple TRPs.

[0257] Example 33: A method according to any one of Examples 21 to 31, wherein the SRS configuration includes a common SRS resource parameter set for the multiple TRPs.

[0258] Example 34: According to any one of the methods of Examples 21 to 33, it also includes: sending at least one transmit power control command, each of the at least one transmit power control command is associated with a TRP among the multiple TRPs.

[0259] Example 35: According to any one of the methods of Examples 21 to 33, further comprising: sending a transmission power control command applicable to each TRP.

[0260] Example 36: A method according to any one of Examples 21 to 35, wherein the SRS resource set includes a non-periodic SRS resource set, and the method further includes: sending control information to the UE, the control information including a code point that triggers the SRS configuration.

[0261] Example 37: A method according to any one of Examples 21 to 35, wherein the SRS resource set includes a non-periodic SRS resource set, and the SRS configuration includes multiple TRP SRS configurations, each TRP SRS configuration is associated with a corresponding TRP in the multiple TRPs, and the method further includes: sending control information to the UE, the control information including a code point that triggers the multiple TRP SRS configurations.

[0262] Example 38: An apparatus for wireless communication, comprising: a processor; a memory coupled to the processor, the processor and the memory being configured to perform a method according to any one of Examples 1 to 20.

[0263] Example 39: An apparatus for wireless communication, comprising: a processor; a memory coupled to the processor, the processor and the memory being configured to perform a method according to any one of Examples 21 to 37.

[0264] Example 40: An apparatus for wireless communication, comprising: at least one unit for performing a method according to any one of Examples 1 to 20.

[0265] Example 41: An apparatus for wireless communication, comprising: at least one unit for performing a method according to any one of Examples 21 to 37.

[0266] Example 42: A non-transitory computer-readable medium storing computer executable code, comprising: code for causing an apparatus to perform a method according to any one of Examples 1 to 20.

[0267] Example 43: A non-transitory computer-readable medium storing computer executable code, comprising: code for causing an apparatus to perform a method according to any one of Examples 21 to 37.

[0268] Example 44: A method for performing wireless communications at a radio access network (RAN) entity in a wireless communication network, the method comprising: sending a sounding reference signal (SRS) configuration for a SRS resource set for a user equipment (UE) to the UE, wherein the SRS resource set comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs); and receiving at least one SRS from the UE based on the SRS configuration.

[0269] Example 45: A method according to Example 44, wherein each TRP of the multiple TRPs includes the same physical cell identifier (PCI).

[0270] Example 46: A method according to Example 45, wherein at least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

[0271] Example 47: A method according to any one of Examples 44 to 46, wherein the RAN entity includes at least one TRP among the multiple TRPs.

[0272] Example 48: A method according to any one of Examples 44 to 47, wherein the multiple TRPs belong to the same timing advance group (TAG), and the multiple SRS resources associated with the multiple TRPs are located within consecutive symbols of a time slot.

[0273] Example 49: A method according to any one of Examples 44 to 47, wherein at least two of the multiple TRPs belong to different corresponding TAGs, and the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TAG and a second SRS resource set associated with a second TAG, and the method further includes: determining a gap length of at least one symbol to be applied between the first SRS resource set and the second SRS resource set; and sending an indication of the gap length to the UE.

[0274] Example 50: A method according to any one of Examples 44 to 47, wherein the multiple SRS resources associated with the multiple TRPs include a first SRS resource set associated with a first TRP among the multiple TRPs and a second SRS resource set associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-site (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association, and the method further includes: determining a gap length of at least one symbol to be applied between the first SRS resource set and the second SRS resource set; and sending an indication of the gap length to the UE.

[0275] Example 51: The method of Example 50, wherein the determining the gap length further comprises: determining the gap length based on the capability of the UE.

[0276] Example 52: According to any one of Examples 44 to 51, the method further includes: sending at least one transmit power control command to the UE, each of the at least one transmit power control command being associated with a corresponding TRP among the multiple TRPs.

[0277] Example 53: According to any one of Examples 44 to 51, the method further includes: sending a transmit power control command applicable to each TRP in the TRP to the UE.

[0278] Example 54: An apparatus for wireless communication, comprising: a processor; a memory coupled to the processor, the processor and the memory being configured to perform a method according to any one of Examples 44 to 53.

[0279] Example 55: An apparatus for wireless communication, comprising: at least one unit for performing a method according to any one of Examples 44 to 53.

[0280] Example 56: A non-transitory computer-readable medium storing computer executable code, comprising: code for causing an apparatus to perform a method according to any one of Examples 44 to 53.

[0281] Several aspects of wireless communication networks have been presented with reference to exemplary implementations. As those skilled in the art will readily appreciate, various aspects described throughout this disclosure may be extended to other telecommunication systems, network architectures and communication standards.

[0282] For example, various aspects may be implemented within other systems defined by 3GPP, such as Long Term Evolution (LTE), Evolved Packet System (EPS), Universal Mobile Telecommunications System (UMTS), and / or Global System for Mobile Communications (GSM). Various aspects may also be extended to systems defined by the Third Generation Partnership Project 2 (3GPP2), such as CDMA2000 and / or Evolution-Data Optimized (EV-DO). Other examples may be implemented within systems employing IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Ultra Wideband (UWB), Bluetooth, and / or other suitable systems. The actual telecommunication standard, network architecture, and / or communication standard employed depends on the specific application and the overall design constraints imposed on the system.

[0283] In this disclosure, the word "exemplary" is used to mean "serving as an example, instance, or illustration." Any implementation or aspect described herein as "exemplary" should not be construed as being preferred or having advantages over other aspects of the disclosure. Likewise, the term "aspect" does not require that all aspects of the disclosure include the features, advantages, or modes of operation discussed. The term "coupling" is used herein to refer to a direct coupling or an indirect coupling between two objects. For example, if object A physically contacts object B, and object B contacts object C, objects A and C can still be considered to be coupled to each other, even if they are not in direct physical contact with each other. For example, a first object can be coupled to a second object, even if the first object has never been in direct physical contact with the second object. The terms "circuit" and "circuitry" are used broadly, and are intended to include both hardware implementations of electronic devices and conductors (which, when connected and configured, enable the performance of the functions described in this disclosure, without limitation as to the type of electronic circuitry) and software implementations of information and instructions (which, when executed by a processor, enable the performance of the functions described in this disclosure).

[0284] Can be Figure 1-17 One or more of the components, steps, features, and / or functions shown in the present disclosure may be rearranged and / or combined into a single component, step, feature, or function, or embodied in several components, steps, or functions. In addition, additional elements, components, steps, and / or functions may be added without departing from the novel features disclosed herein. Figure 1 , 3 , 4, 7-12, 16 and / or 17. The devices, apparatuses and / or components shown in the embodiments may be configured to perform one or more of the methods, features or steps described herein. The novel algorithms described herein may also be efficiently implemented in software and / or embedded in hardware.

[0285] It is to be understood that the specific order or hierarchy of steps in the methods disclosed herein is an illustration of an exemplary process. It is to be understood that the specific order or hierarchy of steps in these methods may be rearranged based on design preferences. The attached method claims present elements of the various steps in an example order, but are not intended to be limited to the specific order or hierarchy presented unless expressly recorded herein.

[0286] The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Therefore, the claims are not intended to be limited to the various aspects shown herein, but to be given the full scope consistent with the text of the claims, wherein unless explicitly stated otherwise, reference to an element in the singular form is not intended to mean "one and only one", but "one or more". Unless otherwise explicitly stated, the term "some" refers to one or more. A phrase referring to "at least one" in a list of items refers to any combination of those items, including a single member. For example, "at least one of a, b, or c" is intended to cover: a; b; c; a and b; a and c; b and c; and a, b, and c. All structural and functional equivalents of the elements of the various aspects described throughout the present disclosure, which are known or will be known to those skilled in the art, are expressly incorporated herein by reference, and are intended to be included by the claims. In addition, no disclosure herein is intended to be dedicated to the public, regardless of whether such disclosure is explicitly recorded in the claims.

Claims

1. An apparatus configured for wireless communication at a user equipment (UE), comprising: one or more processors; as well as one or more memories coupled to the one or more processors, wherein the one or more processors are configured to cause the UE to: Receiving a sounding reference signal (SRS) configuration for a set of SRS resources, wherein the set of SRS resources comprises a plurality of transmit receive points (TRPs) associated with a plurality of SRS resources, wherein the SRS configuration comprises a gap length of at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; providing the gap length between the first set of SRS resources in the plurality of SRS resources and the second set of SRS resources in the plurality of SRS resources; and Multiple SRSs are sent to the multiple TRPs according to the SRS configuration and the gap length.

2. The device according to claim 1, wherein: Each of the multiple TRPs includes the same physical cell identifier (PCI).

3. The device according to claim 1, wherein: At least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

4. The device according to claim 1, wherein: The one or more processors are further configured to cause the UE to: The SRS configuration is received from a TRP among the multiple TRPs.

5. The device according to claim 1, wherein: The first SRS resource set is associated with a first TRP among the multiple TRPs and the second SRS resource set is associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-site (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association.

6. The device according to claim 5, wherein: The one or more processors are further configured to cause the UE to: The SRS configuration is received from a TRP among the multiple TRPs.

7. The device according to claim 1, wherein: The SRS configuration includes at least one of the following: a corresponding SRS resource set parameter set for each TRP in the multiple TRPs, or a common SRS resource set parameter set for the multiple TRPs.

8. The apparatus according to claim 1, further comprising: one or more transceivers coupled to the one or more processors and the one or more memories, wherein the one or more processors are further configured to cause the UE to: receiving, via the transceiver, a plurality of transmit power control commands, each transmit power control command being associated with a TRP in the plurality of TRPs; and The multiple SRSs are sent to the multiple TRPs via the transceiver based on the multiple transmit power control commands with corresponding transmit powers for each of the multiple TRPs.

9. The device according to claim 1, wherein: The one or more processors are further configured to cause the UE to: receiving a transmit power control command applicable to each of the TRPs; and Based on the transmit power control command, the multiple SRSs are sent to the multiple TRPs with the same transmit power for each of the multiple SRSs.

10. The device according to claim 9, wherein: The plurality of SRS resources associated with the plurality of TRPs include a first set of SRS resources associated with a first TRP in the plurality of TRPs and a second set of SRS resources associated with a second TRP in the plurality of TRPs, and wherein the one or more processors are further configured to cause the UE to: receiving the transmit power control command for the first SRS resource set; and Applying the transmit power control command to the second SRS resource set.

11. The device according to claim 1, wherein: The SRS resource set comprises an aperiodic SRS resource set, and the SRS configuration comprises a plurality of TRP SRS configurations, each TRP SRS configuration being associated with a respective TRP of the plurality of TRPs, and wherein the one or more processors are further configured to cause the UE to: Receive control information including code points that trigger the multiple TRP SRS configurations.

12. A method for wireless communication at a user equipment (UE), the method comprising: Receiving a sounding reference signal (SRS) configuration for a set of SRS resources, wherein the set of SRS resources comprises a plurality of transmit receive points (TRPs) associated with a plurality of SRS resources, wherein the SRS configuration comprises a gap length of at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; providing the gap length between the first set of SRS resources in the plurality of SRS resources and the second set of SRS resources in the plurality of SRS resources; and Multiple SRSs are sent to the multiple TRPs according to the SRS configuration and the gap length.

13. The method according to claim 12, wherein: Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

14. The method according to claim 12, wherein: At least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

15. The method according to claim 12, wherein: The first SRS resource set is associated with a first TRP among the multiple TRPs and the second SRS resource set is associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-site (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association.

16. The method according to claim 12, wherein: The SRS configuration includes at least one of the following: a corresponding SRS resource set parameter set for each TRP in the multiple TRPs, or a common SRS resource set parameter set for the multiple TRPs.

17. The method according to claim 12, further comprising: receiving a plurality of transmit power control commands, each transmit power control command being associated with a TRP in the plurality of TRPs; as well as Based on the multiple transmit power control commands, the multiple SRSs are sent to the multiple TRPs with a corresponding transmit power for each TRP in the multiple TRPs.

18. The method according to claim 12, further comprising: receiving a transmit power control command applicable to each of the TRPs; as well as Based on the transmit power control command, the multiple SRSs are sent to the multiple TRPs with the same transmit power for each of the multiple SRSs.

19. The method according to claim 12, wherein: The SRS resource set includes a non-periodic SRS resource set, and the SRS configuration includes a plurality of TRP SRS configurations, each TRP SRS configuration is associated with a corresponding TRP in the plurality of TRPs, and further includes: Receive control information including code points that trigger the multiple TRP SRS configurations.

20. An apparatus configured for wireless communication at a radio access network (RAN) entity, comprising: one or more processors; as well as one or more memories coupled to the one or more processors, wherein the one or more processors are configured to cause the RAN entity to: Providing a sounding reference signal (SRS) configuration for a sounding reference signal (SRS) resource set for a user equipment (UE), wherein the SRS resource set includes a plurality of SRS resources associated with a plurality of transmit receive points (TRPs), wherein the SRS configuration includes a gap length to be applied to at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; and At least one SRS is acquired according to the SRS configuration and the gap length.

21. The device according to claim 20, wherein: Each of the multiple TRPs includes the same physical cell identifier (PCI).

22. The device according to claim 20, wherein: At least two TRPs of each TRP in the plurality of TRPs include different corresponding PCIs.

23. The device according to claim 20, wherein: The RAN entity includes at least one TRP among the multiple TRPs.

24. The device according to claim 20, wherein: The first SRS resource set is associated with a first TRP among the multiple TRPs and the second SRS resource set is associated with a second TRP among the multiple TRPs, the first SRS resource set includes a first quasi-co-site (QCL) association, and the second SRS resource set includes a second QCL association different from the first QCL association.

25. The device according to claim 20, wherein: The one or more processors are further configured to cause the RAN entity to: The gap length is determined based on a capability of the UE.

26. The device according to claim 20, wherein: The SRS configuration includes at least one of the following: a corresponding SRS resource parameter set for each TRP in the multiple TRPs, or a common SRS resource parameter set for the multiple TRPs.

27. The device according to claim 20, wherein: The one or more processors are further configured to cause the RAN entity to: At least one transmit power control command is provided to the UE, each of the at least one transmit power control command being associated with a corresponding TRP among the multiple TRPs.

28. The device according to claim 20, wherein: The one or more processors are further configured to cause the RAN entity to: Provide transmit power control commands applicable to each TRP in the TRP.

29. The device according to claim 20, wherein: The SRS resource set comprises an aperiodic SRS resource set, and the SRS configuration comprises a plurality of TRP SRS configurations, each TRP SRS configuration being associated with a respective TRP of the plurality of TRPs, and wherein the one or more processors are further configured to cause the RAN entity to: Provide control information, wherein the control information includes code points that trigger the multiple TRP SRS configurations.

30. A method for wireless communication at a radio access network (RAN) entity in a wireless communication network, the method comprising: providing a user equipment (UE) with a sounding reference signal (SRS) configuration for a set of SRS resources for the UE, wherein the set of SRS resources comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs), wherein the SRS configuration comprises a gap length to be applied to at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; and At least one SRS is acquired from the UE according to the SRS configuration and the gap length.

31. The method according to claim 30, wherein: Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

32. A non-transitory computer-readable medium having stored therein instructions executable by one or more processors of a user equipment (UE) to: receiving a sounding reference signal (SRS) configuration for an SRS resource set, wherein: The SRS resource set includes a plurality of SRS resources associated with a plurality of transmit reception points (TRPs), wherein the SRS configuration includes a gap length of at least one symbol between a first SRS resource set of the plurality of SRS resources and a second SRS resource set of the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first SRS resource set is associated with a first TAG, and the second SRS resource set is associated with a second TAG; providing the gap length between the first set of SRS resources in the plurality of SRS resources and the second set of SRS resources in the plurality of SRS resources; and Multiple SRSs are sent to the multiple TRPs according to the SRS configuration and the gap length.

33. The non-transitory computer readable medium of claim 32, wherein: Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

34. A non-transitory computer-readable medium having stored therein instructions executable by one or more processors of a radio access network (RAN) entity to: A sounding reference signal (SRS) configuration for a user equipment (UE) resource set is provided, wherein: The SRS resource set comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs), wherein the SRS configuration comprises a gap length to be applied to at least one symbol between a first SRS resource set of the plurality of SRS resources and a second SRS resource set of the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first SRS resource set is associated with a first TAG, and the second SRS resource set is associated with a second TAG; and At least one SRS is acquired according to the SRS configuration and the gap length.

35. The non-transitory computer readable medium of claim 34, wherein: Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

36. An apparatus configured for wireless communication at a user equipment (UE), comprising: Unit for receiving a sounding reference signal (SRS) configuration for a set of SRS resources, wherein the set of SRS resources comprises a plurality of transmit receive points (TRPs) associated with a plurality of SRS resources, wherein the SRS configuration comprises a gap length of at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; means for providing the gap length between the first set of SRS resources in the plurality of SRS resources and the second set of SRS resources in the plurality of SRS resources; and A unit for sending multiple SRSs to the multiple TRPs based on the SRS configuration and the gap length.

37. The device according to claim 36, wherein Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

38. An apparatus configured for wireless communication at a radio access network (RAN) entity, comprising: A unit for providing a sounding reference signal (SRS) configuration for a set of SRS resources for a user equipment (UE), wherein the set of SRS resources comprises a plurality of SRS resources associated with a plurality of transmit receive points (TRPs), wherein the SRS configuration comprises a gap length to be applied to at least one symbol between a first set of SRS resources in the plurality of SRS resources and a second set of SRS resources in the plurality of SRS resources, wherein at least two of the plurality of TRPs belong to different respective timing advance groups (TAGs), the first set of SRS resources is associated with a first TAG, and the second set of SRS resources is associated with a second TAG; and means for acquiring at least one SRS based on the SRS configuration and the gap length.

39. The device according to claim 38, wherein Each of the plurality of TRPs includes a same physical cell identifier (PCI), or at least two TRPs of each of the plurality of TRPs include different corresponding PCIs.

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