Techniques for mapping sounding reference signal resources

Abstract

Methods, systems, and apparatus for wireless communications are described. A base station may receive a capability message from a user equipment (UE) based on the number of receive antennas at the UE exceeding the number of transmit antennas. The base station may configure a mapping between a sounding reference signal (SRS) resource and a bit sequence, or an SRS resource index (SRI), for the UE based on the capability message. The base station may send a control message including one or more SRIs indicating corresponding SRS resources. The UE may use the one or more SRIs included in the control message from the base station to select corresponding SRS resources from a resource set. Once the UE selects the one or more SRS resources, the UE may transmit one or more SRSs in the SRS resources.

Description

Technical Field

[0001] The following relates to wireless communications, including techniques for mapping sounding reference signal (SRS) resources. Background Art

[0002] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, etc. These systems can support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems that may be referred to as new radio (NR) systems. These systems may employ techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations or one or more network access nodes, each base station or network access node simultaneously supporting communication for multiple communication devices, which may be referred to as user equipment (UE). Summary of the Invention

[0003] The described technology relates to methods, systems, devices, and apparatuses that support techniques for mapping sounding reference signal (SRS) resources. Generally, the described technology enables a base station to configure a mapping between SRS resources and a bit sequence (or SRS resource index (SRI)) for a user equipment (UE) based on a capability message from the UE. In some cases, the UE can use one or more SRIs included in a control message from the base station to select corresponding SRS resources from a default resource set (e.g., a resource set with a minimum identifier). In some other cases, in addition to the one or more SRIs, the base station can also include an SRS set indicator in the control message. In some examples, the base station can establish a lookup table and configure a mapping table for the UE to map one or more SRIs in the control message to each SRS resource in one resource set or multiple resource sets (e.g., based on a bit sequence). In some other examples, the UE can use one or more SRIs in the control message to select SRS resources from a static virtual resource set that can be indicated in the control signaling or a dynamic virtual resource set that can be based on a time slot index. Once the UE selects one or more SRS resources, the UE can send one or more SRSs in the SRS resources.

[0004] A method for wireless communication at a user equipment (UE) is described. The method may include: sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; receiving an SRS configuration for a set of multiple SRS resources based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and sending a first SRS in the first SRS resource based on the control message.

[0005] A device for wireless communication at a UE is described. The device may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the device to: send a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; based on the capability message, receive an SRS configuration for a set of multiple SRS resources, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; receive a control message including a first bit sequence in the set of multiple bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and send a first SRS in the first SRS resource based on the control message.

[0006] Another apparatus for wireless communication at a UE is described. The apparatus may include: a component for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; a component for receiving an SRS configuration for a set of multiple SRS resources based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; a component for receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and a component for sending a first SRS in the first SRS resource based on the control message.

[0007] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: send a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; receive an SRS configuration for a set of multiple SRS resources based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; receive a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and send a first SRS in the first SRS resource based on the control message.

[0008] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers.

[0009] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first identifier may be a highest or lowest identifier in a set of the plurality of identifiers corresponding to the set of the plurality of resource sets.

[0010] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving an SRS configuration may include operations, features, components, or instructions for receiving an SRS configuration indicating a set of multiple resource sets, wherein the control message indicates a first resource set in the set of multiple resource sets that can be associated with a subset of the set of multiple SRS resources and indicates a first SRS resource in the subset of the set of multiple SRS resources.

[0011] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving a control message including a set indicator having a zero value, the set indicator indicating a first resource set in the set of the multiple resource sets.

[0012] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving a control message including a set indicator having a non-zero value, the set indicator indicating a first resource set in the set of the multiple resource sets.

[0013] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving a control message including a resource indicator having a zero value, the set indicator indicating a first SRS resource in a subset of the set of the multiple SRS resources.

[0014] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving a control message including a resource indicator having a non-zero value, the set indicator indicating a first SRS resource in a subset of the set of the multiple SRS resources.

[0015] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving an SRS configuration may include operations, features, components, or instructions for receiving an SRS configuration indicating a single resource set associated with the set of multiple SRS resources based on the capability message, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0016] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for receiving an SRS configuration indicating a set of multiple resource sets based on the capability message, each SRS resource in the set of multiple SRS resources being associated with a corresponding resource set in the set of multiple resource sets, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0017] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the SRS configuration may include operations, features, components, or instructions for receiving an SRS configuration indicating a virtual resource set comprising a subset of the set of the multiple SRS resources, wherein the virtual resource set comprises a first SRS resource from the first resource set and a second SRS resource from the second resource set.

[0018] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the SRS configuration may include operations, features, components, or instructions for receiving an SRS configuration indicating a virtual resource set comprising a subset of the set of the multiple SRS resources, wherein based on a time slot index corresponding to the control message, the first SRS resource may be included in the subset of the set of the multiple SRS resources.

[0019] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control message may include operations, features, components, or instructions for receiving a control message indicating a resource set identifier of a first resource set corresponding to the set of the multiple SRS resources.

[0020] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first sequence includes a single bit.

[0021] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first number of the one or more transmit antennas and the third number of the one or more ports may be the same.

[0022] A method for wireless communication at a base station is described. The method may include: receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; sending an SRS configuration for a set of multiple SRS resources to the UE based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; sending a control message including a first bit sequence in the set of multiple bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and receiving a first SRS in the first SRS resource based on the control message.

[0023] An apparatus for wireless communication at a base station is described. The apparatus may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to: receive a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; send an SRS configuration for a set of multiple SRS resources to the UE based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; send a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and receive a first SRS in the first SRS resource based on the control message.

[0024] Another apparatus for wireless communication at a base station is described. The apparatus may include: a component for receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; a component for sending an SRS configuration for a set of multiple SRS resources to the UE based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; a component for sending a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and a component for receiving a first SRS in the first SRS resource based on the control message.

[0025] A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: receive a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; send an SRS configuration for a set of multiple SRS resources to the UE based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences; send a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping; and receive a first SRS in the first SRS resource based on the control message.

[0026] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers.

[0027] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first identifier may be a highest or lowest identifier in a set of the plurality of identifiers corresponding to the set of the plurality of resource sets.

[0028] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending an SRS configuration may include operations, features, components, or instructions for sending an SRS configuration indicating a set of multiple resource sets, wherein the control message indicates a first resource set in the set of multiple resource sets that can be associated with a subset of the set of multiple SRS resources and indicates a first SRS resource in the subset of the set of multiple SRS resources.

[0029] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending a control message including a set indicator having a zero value, the set indicator indicating a first resource set in the set of the multiple resource sets.

[0030] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending a control message including a set indicator having a non-zero value, the set indicator indicating a first resource set in the set of the multiple resource sets.

[0031] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending a control message including a resource indicator having a zero value, the set indicator indicating a first SRS resource in a subset of the set of the multiple SRS resources.

[0032] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending a control message including a resource indicator having a non-zero value, the set indicator indicating a first SRS resource in a subset of the set of the multiple SRS resources.

[0033] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending an SRS configuration may include operations, features, components, or instructions for sending an SRS configuration indicating a single resource set associated with the set of multiple SRS resources based on the capability message, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0034] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for sending an SRS configuration indicating a set of multiple resource sets based on the capability message, each SRS resource in the set of multiple SRS resources being associated with a corresponding resource set in the set of multiple resource sets, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0035] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the SRS configuration may include operations, features, components, or instructions for sending an SRS configuration indicating a virtual resource set comprising a subset of the set of the multiple SRS resources, wherein the virtual resource set comprises a first SRS resource from the first resource set and a second SRS resource from the second resource set.

[0036] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the SRS configuration may include operations, features, components, or instructions for sending an SRS configuration indicating a virtual resource set comprising a subset of the set of the multiple SRS resources, wherein based on a time slot index corresponding to the control message, the first SRS resource may be included in the subset of the set of the multiple SRS resources.

[0037] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the control message may include operations, features, components, or instructions for sending a control message indicating a resource set identifier of a first resource set corresponding to the set of the multiple SRS resources.

[0038] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first sequence includes a single bit.

[0039] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first number of the one or more transmit antennas and the third number of the one or more ports may be the same. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 and Figure 2

[0014] An example of a wireless communication system supporting techniques for mapping sounding reference signal (SRS) resources in accordance with aspects of the present disclosure is shown.

[0041] Figures 3 to 9 An example of a resource map supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0042] Figure 10An example of a process flow supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0043] Figure 11 and Figure 12 A block diagram of a device supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0044] Figure 13 A block diagram of a communication manager supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0045] Figure 14 A diagram is shown of a system including devices supporting techniques for mapping SRS resources in accordance with aspects of the present disclosure.

[0046] Figure 15 and Figure 16 A block diagram of a device supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0047] Figure 17 A block diagram of a communication manager supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown.

[0048] Figure 18 A diagram is shown of a system including devices supporting techniques for mapping SRS resources in accordance with aspects of the present disclosure.

[0049] Figures 19 to 23 Shown is a flow chart illustrating a method supporting techniques for mapping SRS resources according to aspects of the present disclosure. DETAILED DESCRIPTION

[0050] In some wireless communication systems, a user equipment (UE) may send a sounding reference signal (SRS) to a base station during at least one SRS resource so that the base station can determine one or more channel conditions at the UE (e.g., for scheduling uplink transmissions). In some examples, the base station may configure multiple SRS resources for the UE in an aperiodic, semi-persistent, or periodic configuration, and the multiple SRS resources may be grouped into resource sets based on the use case (e.g., grouped for antenna switching, based on or not based on a codebook, for beam management, etc.). For example, the UE may perform an SRS antenna switching operation to achieve downlink beamforming in a time division duplex (TDD) band by using channel reciprocity (e.g., the channel response may be the same in both directions). In addition, SRS antenna switching may be used for uplink sounding (e.g., for physical uplink shared channel scheduling and / or beamforming). During the antenna switching operation, the base station may configure multiple resource sets for the UE. In some other examples, such as for codebook-based transmissions, the base station may configure a single resource set for the UE. It may be beneficial for the UE to combine the use of downlink channel state information (CSI) acquisition during antenna switching operations with uplink codebook selection to reduce the signaling overhead associated with SRS transmission. However, antenna switching operations and codebook-based transmissions may use different numbers of resource sets (e.g., one and two).

[0051] As described herein, a base station may configure a mapping between SRS resources and an SRI bit sequence for a UE, and the UE may transmit an SRS during an SRS resource period based on receiving an indication of a particular bit sequence. The UE may have x transmit antennas and y receive antennas for antenna switching operations. In addition, the UE may have a number of ports that support uplink transmission. In some examples, if x is less than or equal to y, the UE may send a capability message for combining a resource set for antenna switching operations with codebook-based transmission. The capability message may include an indication of x, y, and the number of ports supported for uplink transmission. The base station may send control signaling based on the capability message, which includes an SRS configuration for the SRS resources and a bit sequence that is mapped to the SRS resources based on the SRS configuration. For example, the UE may receive an identifier for each resource set that includes an SRS resource. The UE may use a default resource set based on the resource set with the smallest identifier. The UE may use an SRS resource index (SRI), which may be a single bit sequence, included in the control signaling to select an SRS resource from the resource set with the smallest identifier for transmitting the SRS. Additionally or alternatively, the UE may receive a separate indication of a resource set identifier for a resource set that includes the SRS resources indicated by the SRI (e.g., instead of using a default resource set). In some examples, the SRI may be a three-digit indicator that the UE may map to SRS resources in a single resource set or multiple resource sets. In some cases, the control signaling may include an indication for causing the UE to use a static virtual resource set, which may include one or more fixed or static SRS resources from different resource sets. In some other cases, the control signaling may include an indication for causing the UE to use a dynamic virtual resource set, which may be based on a time slot index. The UE may use the SRI included in the control signaling to select resources from the static virtual resource set or the dynamic virtual resource set.

[0052] Various aspects of the present disclosure are initially described in the context of wireless communication systems. Aspects of the present disclosure are further described in the context of resource maps and process flows. Aspects of the present disclosure are further illustrated and described with reference to apparatus diagrams, system diagrams, and flow charts related to techniques for mapping SRS resources.

[0053] Figure 1An example of a wireless communication system 100 that supports techniques for mapping SRS resources according to aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an Advanced LTE (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission-critical) communications, low-latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

[0054] Base stations 105 may be dispersed throughout a geographic area to form wireless communication system 100 and may be devices of varying form factors or capabilities. Base stations 105 and UEs 115 may communicate wirelessly via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which UEs 115 and base stations 105 may establish one or more communication links 125. Coverage areas 110 may be examples of geographic areas over which base stations 105 and UEs 115 may support communication of signals according to one or more radio access technologies.

[0055] UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary, mobile, or both at different times. UEs 115 may be devices of different forms or capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. Figure 1 As shown, the UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, base stations 105, or network devices (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network devices).

[0056] The base stations 105 can communicate with the core network 130, with each other, or with both. For example, the base stations 105 can be connected to the core network 130 via one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). The base stations 105 can communicate with each other via the backhaul links 120 (e.g., via X2, Xn, or other interfaces) directly (e.g., directly between the base stations 105) or indirectly (e.g., through the core network 130), or both. In some examples, the backhaul links 120 can be or include one or more wireless links.

[0057] One or more of the base stations 105 described herein may include or may be referred to by one of ordinary skill in the art as: a base transceiver station, a radio base station, an access point, a radio transceiver, a Node B, an eNode B (eNB), a next generation Node B or a Gigabit Node B (any of which may be referred to as a gNB), a Home Node B, a Home eNode B, or other suitable terminology.

[0058] UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where a "device" may also be referred to as a unit, a station, a terminal, or a client, among other examples. UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a notebook computer, or a personal computer. In some examples, UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in various objects, such as appliances or vehicles, meters, etc.

[0059] The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, which may sometimes act as relays, as well as base stations 105 and network equipment (including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations), and other examples, such as Figure 1 shown.

[0060] The UE 115 and the base station 105 can wirelessly communicate with each other over one or more carriers via one or more communication links 125. The term "carrier" may refer to a collection of radio spectrum resources having a defined physical layer structure for supporting the communication link 125. For example, a carrier used for the communication link 125 may include a portion of a radio spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communication with the UE 115 using carrier aggregation or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used with frequency division duplex (FDD) and time division duplex (TDD) component carriers.

[0061] In some examples (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. A carrier may be associated with a frequency channel (e.g., an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) Absolute Radio Frequency Channel Number (EARFCN)) and may be located based on a channel raster for discovery by a UE 115. A carrier may operate in a standalone mode, where a UE 115 may perform initial acquisition and connection via the carrier, or a carrier may operate in a non-standalone mode, where a connection is anchored using a different carrier (e.g., of the same or different radio access technology).

[0062] The communication link 125 shown in the wireless communication system 100 may include an uplink transmission from the UE 115 to the base station 105, or a downlink transmission from the base station 105 to the UE 115. A carrier may carry downlink or uplink communications (e.g., in FDD mode) or may be configured to carry both downlink and uplink communications (e.g., in TDD mode).

[0063] A carrier can be associated with a particular bandwidth of a radio spectrum, and in some examples, the carrier bandwidth can be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth can be one of a plurality of determined bandwidths of a carrier for a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz)). The devices of the wireless communication system 100 (e.g., base station 105, UE 115, or both) can have a hardware configuration that supports communication on a particular carrier bandwidth, or can be configured to support communication on one of a set of carrier bandwidths. In some examples, the wireless communication system 100 can include a base station 105 or UE 115 that supports simultaneous communication via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 can be configured to operate on a portion (e.g., a subband, BWP) or all of the carrier bandwidth.

[0064] The signal waveform transmitted on the carrier may be composed of multiple subcarriers (e.g., using a multicarrier modulation (MCM) technique such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system employing MCM techniques, a resource element may comprise one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both). Therefore, the more resource elements received by the UE 115 and the higher the order of the modulation scheme, the higher the data rate of the UE 115 may be. Wireless communication resources may refer to a combination of radio spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial layers may further increase the data rate or data integrity of communications with the UE 115.

[0065] One or more parameter sets for a carrier may be supported, where the parameter set may include subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs with the same or different parameter sets. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time, and communications by the UE 115 may be restricted to the one or more active BWPs.

[0066] The time interval of the base station 105 or the UE 115 may be expressed as a multiple of a basic time unit, which may be, for example, T s =1 / (Δf max ·N f ) seconds sampling period, where Δf max It can represent the maximum supported subcarrier spacing, and N f The maximum supported Discrete Fourier Transform (DFT) size may be indicated. Time intervals for communication resources may be organized according to radio frames, each radio frame having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a System Frame Number (SFN) (e.g., ranging from 0 to 1023).

[0067] Each frame can include multiple consecutively numbered subframes or time slots, and each subframe or time slot can have the same duration. In some examples, the frame can be divided into subframes (e.g., in the time domain), and each subframe can be further divided into multiple time slots. Alternatively, each frame can include a variable number of time slots, and the number of time slots can depend on the subcarrier spacing. Each time slot can include multiple symbol periods (e.g., depending on the length of the cyclic prefix appended to each symbol period). In some wireless communication systems 100, the time slot can be further divided into multiple micro-time slots including one or more symbols. In addition to the cyclic prefix, each symbol period can include one or more (e.g., N) subframes. f ) sampling period. The duration of a symbol period may depend on the subcarrier spacing or the frequency band of operation.

[0068] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI)).

[0069] Physical channels can be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels can be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM), frequency division multiplexing (FDM), or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET)) of a physical control channel can be defined by multiple symbol periods and can extend across the system bandwidth of a carrier or a subset of the system bandwidth. One or more control regions (e.g., CORESETs) can be configured for a set of UEs 115. For example, one or more of the UEs 115 can monitor or search the control region for control information according to one or more search space sets, and each search space set can include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate can refer to the number of control channel resources (e.g., control channel elements (CCEs)) associated with coded information of a control information format having a given payload size. A search space set can include a common search space set configured for transmitting control information to multiple UEs 115 and a UE-specific search space set for transmitting control information to a specific UE 115.

[0070] Each base station 105 can provide communication coverage through one or more cells, such as macro cells, small cells, hot spots, or other types of cells, or any combination thereof. The term "cell" can refer to a logical communication entity used to communicate with the base station 105 (e.g., via a carrier) and can be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other) used to distinguish adjacent cells. In some examples, a cell can also refer to a geographic coverage area 110 or a portion of a geographic coverage area 110 (e.g., a sector) on which the logical communication entity operates. Depending on various factors such as the capabilities of the base station 105, such cells can range from a smaller area (e.g., a structure, a subset of a structure) to a larger area. For example, a cell can be or include a building, a subset of a building, or an external space between or overlapping the geographic coverage area 110, among other examples.

[0071] A macro cell typically covers a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access to UEs 115 that have a service subscription with a network provider that supports the macro cell. Small cells may be associated with base stations 105 that are less powerful than macro cells, and the small cells may operate in the same or different frequency bands (e.g., licensed, unlicensed) as the macro cells. Small cells may provide unrestricted access to UEs 115 that have a service subscription with a network provider, or may provide restricted access to UEs 115 associated with the small cell (e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associated with users in a home or office). A base station 105 may support one or more cells and may also support communication over one or more cells using one or more component carriers.

[0072] In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that may provide access to different types of devices.

[0073] In some examples, base stations 105 can be mobile and, therefore, provide communication coverage for mobile geographic coverage areas 110. In some examples, different geographic coverage areas 110 associated with different technologies can overlap, but the different geographic coverage areas 110 can be supported by the same base station 105. In other examples, overlapping geographic coverage areas 110 associated with different technologies can be supported by different base stations 105. The wireless communication system 100 can include, for example, a heterogeneous network in which different types of base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

[0074] The wireless communication system 100 can support synchronous or asynchronous operation. For synchronous operation, the base stations 105 can have similar frame timing, and transmissions from different base stations 105 can be approximately aligned in time. For asynchronous operation, the base stations 105 can have different frame timing, and in some examples, transmissions from different base stations 105 can be misaligned in time. The techniques described herein can be used for either synchronous or asynchronous operation.

[0075] Some UEs 115, such as MTC or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC may refer to data communication technology that allows devices to communicate with each other or with a base station 105 without human intervention. In some examples, M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay such information to a central server or application that utilizes the information or presents it to a person interacting with the application. Some UEs 115 may be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based billing for services.

[0076] Some UEs 115 may be configured to employ a reduced power consumption mode of operation, such as half-duplex communication (e.g., a mode that supports one-way communication via transmission or reception, but not simultaneous transmission and reception). In some examples, half-duplex communication may be performed at a reduced peak rate. Other power saving techniques for the UE 115 include entering a power-saving deep sleep mode when not engaged in active communication, operating over a limited bandwidth (e.g., according to narrowband communication), or a combination of these techniques. For example, some UEs 115 may be configured to operate using a narrowband protocol type associated with a defined portion or range (e.g., a set of subcarriers or resource blocks (RBs)) within a carrier, within a guard band of a carrier, or outside of a carrier.

[0077] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC) or mission-critical communication. UE 115 can be designed to support ultra-reliable, low-latency or critical functions (e.g., mission-critical functions). Ultra-reliable communication can include private communication or group communication and can be supported by one or more mission-critical services, such as mission-critical push-to-talk (MCPTT), mission-critical video (MCVideo), or mission-critical data (MCData). Support for mission-critical functions can include service priority, and mission-critical services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission-critical, and ultra-reliable low-latency can be used interchangeably in this article.

[0078] In some examples, UE 115 may also be able to communicate directly with other UEs 115 via device-to-device (D2D) communication links 135 (e.g., using a peer-to-peer (P2P) or device-to-device (D2D) protocol). One or more of the UEs 115 utilizing D2D communication may be within the geographic coverage area 110 of the base station 105. Other UEs 115 in the group may be outside the geographic coverage area 110 of the base station 105 or otherwise unable to receive transmissions from the base station 105. In some examples, the group of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system in which each UE 115 transmits to each other UE 115 in the group. In some examples, the base station 105 facilitates resource scheduling for the D2D communication. In other cases, D2D communication is performed between the UEs 115 without the involvement of the base station 105.

[0079] In some systems, the D2D communication link 135 can be an example of a communication channel between vehicles (e.g., UE 115), such as a sidelink communication channel. In some examples, vehicles can communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination of these communications. Vehicles can signal information related to traffic conditions, signal scheduling, weather, safety, emergency situations, or any other information related to the V2X system. In some examples, vehicles in a V2X system can communicate with roadside infrastructure (such as roadside units), or communicate with a network using vehicle-to-network (V2N) communication through one or more network nodes (e.g., base station 105), or communicate with both.

[0080] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) that manages access and mobility and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) that routes or interconnects packets to external networks. The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for UEs 115 served by base stations 105 associated with the core network 130. User IP packets may be delivered via the user plane entity, which may provide IP address allocation and other functions. The user plane entity may connect to IP services 150 of one or more network operators. The IP services 150 may include access to the Internet, intranet(s), IP multimedia subsystems (IMS), or packet-switched streaming services.

[0081] Some of the network devices, such as base stations 105, may include subcomponents such as access network entities 140, which may be examples of access node controllers (ANCs). Each access network entity 140 may communicate with the UE 115 through one or more other access network transmit entities 145, which may be referred to as radio heads, smart radio heads, or transmit / receive points (TRPs). Each access network transmit entity 145 may include one or more antenna panels. In some configurations, the various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., base station 105).

[0082] The wireless communication system 100 can operate using one or more frequency bands typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Typically, the region from 300 MHz to 3 GHz is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength distance is from about 1 decimeter to 1 meter long. Buildings and environmental features may block or redirect UHF waves, but the waves can sufficiently penetrate the structure of the macrocell to provide service to UEs 115 located indoors. Transmission of UHF waves can be associated with smaller antennas and shorter distances (e.g., less than 100 kilometers) compared to transmission using the lower frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0083] The wireless communication system 100 may also operate in the super high frequency (SHF) region using frequency bands from 3 GHz to 30 GHz (also known as centimeter wave bands), or in the extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) (also known as millimeter wave bands). In some examples, the wireless communication system 100 may support millimeter wave (mmW) communications between the UE 115 and the base station 105, and the EHF antennas of each device may be even smaller and more closely spaced than the UHF antennas. In some examples, this may facilitate the use of antenna arrays within the device. However, the propagation of EHF transmissions may be subject to even greater atmospheric attenuation and a shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed between transmissions using one or more different frequency regions, and the designated use of frequency bands across these frequency regions may vary by country or regulatory body.

[0084] The wireless communication system 100 can utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 can employ license assisted access (LAA), unlicensed LTE (LTE-U) radio access technology, or NR technology in an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in an unlicensed radio frequency spectrum band, devices such as the base station 105 and the UE 115 can employ carrier sensing for conflict detection and avoidance. In some examples, operations in the unlicensed band can be based on a carrier aggregation configuration together with component carriers operating in a licensed band (e.g., LAA). Operations in the unlicensed spectrum can include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among others.

[0085] A base station 105 or a UE 115 may be equipped with multiple antennas that may be used to employ techniques such as transmit diversity, receive diversity, multiple-input, multiple-output (MIMO) communications, or beamforming. The antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays or antenna panels that may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, the antennas or antenna arrays associated with a base station 105 may be located at different geographic locations. A base station 105 may have an antenna array having multiple rows and columns of antenna ports that the base station 105 may use to support beamforming for communications with the UE 115. Similarly, a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panels may support radio frequency beamforming for signals transmitted via the antenna ports.

[0086] The base station 105 or UE 115 can use MIMO communication to take advantage of multipath signal propagation and improve spectral efficiency by sending or receiving multiple signals via different spatial layers. This technique may be referred to as spatial multiplexing. For example, multiple signals may be sent by a transmitting device via different antennas or different antenna combinations. Similarly, multiple signals may be received by a receiving device via different antennas or different antenna combinations. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers may be associated with different antenna ports for channel measurement and reporting. MIMO technologies include single-user MIMO (SU-MIMO), in which multiple spatial layers are sent to the same receiving device, and multi-user MIMO (MU-MIMO), in which multiple spatial layers are sent to multiple devices.

[0087] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting device or a receiving device (e.g., a base station 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming can be achieved by combining signals communicated via antenna elements in an antenna array so that signals propagating at a particular orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals communicated via antenna elements can include the transmitting device or the receiving device applying an offset, a phase offset, or both to the signals carried via the antenna elements associated with the device. The adjustments associated with each antenna element can be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device, or relative to some other direction).

[0088] The base station 105 or the UE 115 may use beam sweeping techniques as part of a beamforming operation. For example, the base station 105 may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with the UE 115. For example, some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted multiple times by the base station 105 in different directions, which may include transmitting the signals according to different sets of beamforming weights associated with different transmission directions. The transmissions in different beam directions may be used (e.g., by the base station 105 or a receiving device such as the UE 115) to identify the beam direction for subsequent transmissions or receptions by the base station 105.

[0089] Some signals, such as data signals associated with a particular receiving device, may be transmitted by base station 105 in a single beam direction (e.g., a direction associated with a receiving device such as UE 115). In some examples, the beam direction associated with transmission along the single beam direction may be determined based on signals transmitted in one or more beam directions. For example, UE 115 may receive one or more signals transmitted by base station 105 in different directions and may report to base station 105 an indication of the signal received by UE 115 with the highest signal quality or other acceptable signal quality.

[0090] In some examples, transmissions by a device (e.g., base station 105 or UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from base station 105 to UE 115). UE 115 may report feedback indicating precoding weights used for one or more beam directions, and the feedback may correspond to a configured number of beams across the system bandwidth or one or more subbands. Base station 105 may send reference signals (e.g., cell-specific reference signals (CRS), channel state information reference signals (CSI-RS)) that may be precoded or unprecoded. UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook). Although these techniques are described with reference to signals sent by base station 105 in one or more directions, UE 115 may employ similar techniques for sending signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by UE 115) or for sending signals in a single direction (e.g., for sending data to a receiving device).

[0091] When receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from the base station 105, a receiving device (e.g., UE 115) can try multiple reception configurations (e.g., directional listening). For example, the receiving device can try multiple reception directions by receiving via different antenna subarrays, processing received signals according to different antenna subarrays, receiving according to different sets of receive beamforming weights applied to signals received at multiple antenna elements of an antenna array (e.g., different sets of directional listening weights), or processing received signals according to different sets of receive beamforming weights applied to signals received at multiple antenna elements of an antenna array, any of which can be referred to as "listening" according to different reception configurations or reception directions. In some examples, the receiving device can use a single reception configuration to receive along a single beam direction (e.g., when receiving data signals). A single receive configuration may be aligned on a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0092] The wireless communication system 100 can be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or packet data convergence protocol (PDCP) layer can be IP-based. The radio link control (RLC) layer can perform packet segmentation and reassembly to communicate over logical channels. The medium access control (MAC) layer can perform priority processing and multiplex logical channels into transport channels. The MAC layer can also use error detection technology, error correction technology, or both to support retransmission at the MAC layer to improve link efficiency. In the control plane, the radio resource control (RRC) protocol layer can provide the establishment, configuration, and maintenance of an RRC connection between the UE 115 and the base station 105 or the core network 130 that supports radio bearers for user plane data. At the physical layer, transport channels can be mapped to physical channels.

[0093] UE 115 and base station 105 can support retransmission of data to increase the likelihood of successfully receiving the data. Hybrid automatic repeat request (HARQ) feedback is a technique for increasing the likelihood of correctly receiving data over communication link 125. HARQ can include a combination of error detection (e.g., using a cyclic redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ can improve throughput at the MAC layer under poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, a device can support HARQ feedback for the same time slot, wherein the device can provide HARQ feedback in a specific time slot for data received in a previous symbol in the time slot. In other cases, a device can provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0094] UE 115 may use one or more SRS resources to transmit an SRS to base station 105. Base station 105 may configure multiple SRS resources for UE 115, which may be grouped into resource sets, also referred to as resource sets, depending on the use case or usage type (e.g., antenna switching, codebook-based, non-codebook-based, beam-managed). Base station 105 may configure one or more resource sets for UE 115. Each resource set may contain a collection of SRS resources on which UE 115 may transmit an SRS. In some cases, UE 115 may be configured to use (e.g., may be physically present at UE 115 or enabled) several transmit antennas and several receive antennas. UE 115 may perform SRS antenna switching, which may involve UE 115 transmitting one or more SRSs to base station 105 via a transmit antenna and base station 105 utilizing channel reciprocity to perform downlink beamforming for a time division duplex (TDD) channel. Resource sets whose resources are used for antenna switching may be considered to have an antenna switching usage type. For codebook-based transmission, UE 115 may be configured with a single resource set with the usage type set to "codebook." Base station 105 may include an SRI in the control message to indicate the SRS resources within the configured resource set, where the SRI may have one or more bits. UE 115 may send the SRS to base station 105 for codebook-based SRS communication.

[0095] In some cases, each resource set may be mapped to mutually exclusive SRS resources. For example, a resource set associated with an antenna switching usage type (e.g., configured with a usage type set to antenna switching, referred to as an antenna switching resource set) may have different resources than a resource set with a codebook usage type (e.g., configured with a usage type set to codebook, referred to as a codebook resource set). The codebook resource set may be merged with the antenna switching resource set. Merging resource sets (e.g., using downlink channel state information (CSI) acquisition and uplink codebook selection) may reduce the number of configurations for SRS transmission or the total number of resources used to transmit SRS, which may enable the base station 105 to more flexibly schedule resources for other types of transmissions or transmissions from other UEs 115. However, antenna switching operations and codebook-based transmissions may use different numbers of resource sets (e.g., one and two), which may result in high signaling overhead due to a lack of configuration when two resource sets exist for codebook-based SRS transmission.

[0096] In some examples, base station 105 can configure a mapping between SRS resources and bit sequences for UE 115, and UE 115 can transmit an SRS (e.g., codebook-based SRS or antenna switching SRS) during an SRS resource based on receiving an indication of a particular bit sequence. For example, UE 115 can combine one or more resource sets for codebook-based SRS and antenna switching-based SRS (e.g., one resource set for codebook-based SRS and one or more resource sets for antenna switching), which is related to Figure 3 In some cases, the UE 115 may use one or more SRIs included in a control message from the base station 105 to select a corresponding SRS resource from a default resource set (e.g., a resource set with a minimum identifier). Figure 4 In some other cases, in addition to the one or more SRIs, the base station 105 may also include an SRS set indicator in the control message. Figure 5 In some examples, the base station 105 can construct a lookup table to map one or more SRIs in the control message to each SRS resource in a resource set (e.g., based on a bit sequence), which is related to Figure 6 Further details are given, or mapped to each SRS resource in multiple resource sets, which is about Figure 7 In some other examples, UE 115 may use one or more SRIs in the control message to obtain information from the user. Figure 8 The static virtual resource set indicated in the control signaling described in further detail may be based on the Figure 9The SRS resources are selected from a dynamic virtual resource set indexed by a time slot as described in further detail. Once the UE 115 selects one or more SRS resources, the UE 115 may transmit one or more SRSs in the SRS resources. The techniques described herein may combine the use of downlink CSI acquisition and uplink codebook selection to reduce SRS overhead.

[0097] Figure 2 An example of a wireless communication system 200 that supports techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the wireless communication system 200 can implement aspects of the wireless communication system 100 and can include a UE 115-a and a base station 105-a having a coverage area 110-a, which can be as described in reference Figure 1 1 and 2. An example of a UE 115 and a base station 105 is depicted with a coverage area 110. In some examples, the UE 115-a may communicate with the base station 105-a by receiving control signaling or data via a downlink communication link 205, transmitting control signaling or data via an uplink communication link 210, or both. For example, the base station 105-a may configure a mapping between SRS resources and bit sequences, which may be referred to as SRI, for the UE 115-a, and the UE 115-a may transmit SRS 215 during the SRS resources based on receiving an indication of a particular bit sequence.

[0098] UE 115 may use one or more SRS resources to transmit an SRS to base station 105. For example, UE 115-a may use any of SRS resource 1 to SRS resource 13 to transmit an SRS to base station 105-a. The SRS resource may be anywhere within time slot 220, such as any of symbol periods 1 to 13 of the time slot. Base station 105 may configure multiple SRS resources for UE 115, which may be grouped into resource sets, also referred to as SRS resource sets, depending on the use case or type of use (e.g., antenna switching, codebook-based, non-codebook-based, beam management). Base station 105 may configure one or more resource sets for UE 115. For example, base station 105-a may send a control message 225 to UE 115-a indicating the one or more resource sets. Base station 105-a may send control message 225 via RRC signaling or a downlink control information (DCI) message. The base station 105-a may send one or more resource sets to the UE 115-a aperiodically, semi-persistently, or periodically.

[0099] Each resource set may contain a set of SRS resources on which the UE 115-a may transmit SRS, such as resource set 1 (e.g., including SRS resources 1 through SRS resource 4) and resource set 2 (e.g., including SRS resource 5). The UE 115-a and the base station 105-a may support SRS resources spanning 1, 2, 4, 8, or 12 adjacent symbols, each SRS resource having up to a predefined number (e.g., 8) of ports. Up to a predefined number of resource sets (e.g., 2 resource sets) may be configured for SRS sounding with antenna switching. Each port of the SRS resource may be sounded in each symbol. In some cases, the UE 115-a may transmit SRS in the last 6 symbols of a slot, which may be the last 6 SRS resources in the slot (e.g., SRS resources 8 through 13), and may do so after a physical uplink shared channel (PUSCH) transmission has been sent in the slot. The SRS transmitted on the SRS resource may be a wideband SRS or a sub-band SRS, and the bandwidth of each SRS may be a multiple of 4 physical resource blocks (PRBs).

[0100] In some cases, UE 115-a may be configured to use (e.g., may be physically present at UE 115 or enabled) a number of transmit antennas and a number of receive antennas. UE 115-a may use up to that number of transmit antennas to transmit signals and may use up to that number of receive antennas to receive signals. In some cases, the number of transmit antennas and the number of receive antennas may be given by xTyR, where x may be equal to the number of transmit antennas and y may be equal to the number of receive antennas. For example, 1T1R may correspond to UE 115-a having or being configured to use one transmit antenna and one receive antenna.

[0101] UE 115-a may perform SRS antenna switching, which may involve UE 115-a transmitting one or more SRSs to base station 105-a via a transmit antenna, and base station 105-a utilizing channel reciprocity to perform downlink beamforming for a time division duplex (TDD) channel. For example, base station 105-a may receive SRSs, may perform uplink channel estimation, and may utilize channel reciprocity to determine downlink channel estimates based on the uplink channel estimates. Base station 105-a may use the downlink channel estimates to perform downlink beamforming. Additionally or alternatively, UE 115-a may perform SRS antenna switching for uplink sounding (e.g., for PUSCH scheduling or PUSCH beamforming). A resource set whose resources are used for antenna switching may be referred to as having an antenna switching usage type. Generally, if the number of transmissions for xTyR is x≤y (e.g., 1T2R, 2T4R, 1T4R, 1T4R / 2T4R, or T=R), SRS antenna switching may be supported. The number of SRS resources in a resource set used for antenna switching may be given by x / y. For example, an antenna switching resource set for a UE 115 configured with 1T4R may have four SRS resources.

[0102] For codebook based transmissions, the UE 115-a may be configured with a single resource set (e.g., SRS-ResourceSet) with the usage type set to "codebook". The base station 105-a may include an SRI in the control message 225 to indicate an SRS resource (e.g., a single SRS resource) within the configured resource set, where the SRI may have one or more bits. In some examples, a defined (e.g., maximum) number of configured SRS resources for codebook based transmissions may have a predefined value (e.g., 4) (e.g., when a higher layer parameter such as ul-FullPowerTransmission is set to full power mode). Performing codebook based SRS communication may involve the UE 115-a sending an SRS to the base station 105-a for uplink sounding. Based on measurements of the configured SRS, the base station 105-a may sound the channel and may determine an appropriate rank and precoder matrix. Determining the rank and precoder matrix may enable the base station 105-a to perform PUSCH scheduling, beamforming, or both to receive PUSCH transmissions. When performing codebook-based SRS communication, UE 115-a may be configured to transmit at least one multi-port SRS, where a 1-bit or 2-bit SRS resource indicator (SRI) indicates the configured SRS. In some cases, UE 115-a may use multiple SRS beams, where each SRS beam may correspond to a different device antenna panel with a different orientation, and where each panel may include a set of antenna elements corresponding to an antenna port for each multi-port SRS. A resource set whose resources are used for codebook-based SRS communication may be considered to have a codebook usage type.

[0103] In some cases, each resource set may be mapped to mutually exclusive SRS resources. For example, a resource set associated with an antenna switching usage type (e.g., configured with a usage type set to antenna switching, referred to as an antenna switching resource set) may have different resources than a resource set with a codebook usage type (e.g., configured with a usage type set to codebook, referred to as a codebook resource set). The codebook resource set may be merged with the antenna switching resource set. Merging resource sets (e.g., using downlink channel state information (CSI) acquisition and uplink codebook selection) may reduce the number of configurations for SRS transmission or the total number of resources used to transmit SRS, which may enable the base station 105-a to more flexibly schedule resources for other types of transmissions or transmissions from other UEs 115. However, antenna switching operations and codebook-based transmissions may use different numbers of resource sets (e.g., one and two), which may result in high signaling overhead due to a lack of configuration when two resource sets exist for codebook-based SRS transmission.

[0104] In some examples, base station 105 can configure a mapping between SRS resources and bit sequences for UE 115, and UE 115 can transmit an SRS (e.g., codebook-based SRS or antenna switching SRS) during an SRS resource based on receiving an indication of a particular bit sequence. For example, UE 115-a can combine one or more resource sets for codebook-based SRS and antenna switching-based SRS (e.g., one resource set for codebook-based SRS and one or more resource sets for antenna switching), which is related to Figure 3 In some cases, the resource set for codebook-based SRS may have one SRS resource with multiple ports, such as resource set 1. In some other cases, the antenna switching operation may use multiple resources (e.g., the number of resources is ). Multiple resources can be grouped into groups with N s One or more resource sets of resources, each resource having multiple ports. For example, UE 115-a may use S sets for antenna switching operations (e.g., S>1, set>1, set1, set2, ..., setS). Thus, the number of resources may satisfy the sum

[0105] In some examples, the UE 115-a may send a capability message 230 to the base station 105-a. The capability message may indicate x, y, the number of ports supported for uplink transmission at the UE 115-a, or a combination thereof. If y is greater than x (x<y), the UE 115-a may send the capability message 230 to the base station 105-a. In some cases, the base station 105-a may send a control message 225 in response to receiving the capability message 230 from the UE 115-a. The base station 105-a may include an SRI in the control message 225 to indicate to the UE 115-a which SRS resource in the resource set is used for codebook-based SRS transmission (e.g., which resource is associated with a transmit precoding matrix indication (TPMI)). Additionally or alternatively, the base station 105-a may construct a lookup table and configure the UE 115-a with the lookup table that maps the SRI (e.g., included in the control message 225) to the SRS resource.

[0106] In some cases, the UE 115-a may use one or more SRIs included in the control message 225 to select corresponding SRS resources from a default resource set (e.g., a resource set with the smallest identifier). Figure 4 In some other cases, in addition to the one or more SRIs, the base station 105-a may also include an SRS set indicator in the control message 225, which may be related to Figure 5In some examples, the base station 105-a can construct a lookup table to map one or more SRIs in the control message 225 to each SRS resource in a resource set (e.g., based on a bit sequence), which is related to Figure 6 Further details are given, or mapped to each SRS resource in multiple resource sets, which is about Figure 7 In some other examples, UE 115-a may use one or more SRIs in control message 225 to obtain information from a user who may be in a position to access the control message 225. Figure 8 The static virtual resource set indicated in the control signaling described in further detail may be based on the Figure 9 The SRS resources are selected from a dynamic virtual resource set indexed by a time slot as described in further detail. Once the UE 115-a selects one or more SRS resources, the UE 115-a may transmit one or more SRSs in the SRS resources.

[0107] Figure 3 An example of a resource map 300 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 300 can implement aspects of the wireless communication system 100, the wireless communication system 200, or both. The resource map 300 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2 As described. For example, resource diagram 300-a may illustrate an SRS resource configuration for periodic or semi-persistent transmission of a resource set, with four SRS resources per resource set. Resource diagram 300-b may illustrate an SRS resource configuration for aperiodic transmission of a resource set, with four SRS resources per resource set. Resource diagram 300-c may illustrate an SRS resource configuration for periodic or semi-persistent transmission of two resource sets, with two SRS resources per resource set. Resource diagram 300-d may illustrate an SRS resource configuration for aperiodic transmission of two resource sets, with two SRS resources per resource set. Although combinations with one or two resource sets and four or two SRS resources per set are shown in resource diagram 300, reference Figure 1 and Figure 2 The described UE 115 may support any other number of SRS resources and resource sets.

[0108] In some cases, UE 115 may use one or more resource sets for antenna switching operations, while UE 115 may use one resource set for codebook-based SRS transmission. In addition, UE 115 may use multiple SRS resources from one or more resource sets for antenna switching operations, while UE 115 may use one SRS resource from one resource set for codebook-based SRS transmission. UE 115 may have x transmit antennas and y receive antennas, such as four, six, or eight receive antennas (e.g., two transmit antennas (e.g., x=2) and eight receive antennas (e.g., y=8), as shown for resource map 300).

[0109] In some examples, such as for resource diagrams 300-a through 300-d, UE 115 may use two antenna ports for each SRS resource. In resource diagram 300-a, UE 115 may use two antenna ports for each of the four SRS resources in resource set 0, which may be transmitted periodically or semi-persistently based on a periodicity. Similarly, in resource diagram 300-b, UE 115 may use two antenna ports for each of the four SRS resources in resource set 0, which may be transmitted aperiodically (e.g., in response to receiving an SRS trigger) during a time slot based on a time slot offset and a guard period (e.g., a number of symbols) between each SRS resource. In resource diagram 300-c, UE 115 may use two antenna ports for each of the two SRS resources in resource set 0 and resource set 1, which may be transmitted periodically or semi-persistently based on a periodicity. Similarly, in resource diagram 300-d, UE 115 may use two antenna ports for each of two SRS resources in resource set 0 and resource set 1, which may be transmitted non-periodically during a time slot based on a time slot offset and a guard period between each SRS resource.

[0110] In some examples, such as for SRS usage combining, the SRI field in the control message from base station 105 to UE 115 can be enhanced to support a relatively larger number of SRS resource candidates for codebook usage (e.g., eight SRS resource candidates for six or eight receive antennas and one transmit antenna). For example, the SRI field can include multiple bits to support an indication of each SRS resource in a resource set.

[0111] Figure 4An example of a resource map 400 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 400 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, or a combination thereof. The resource map 400 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2 For example, resource diagram 400 may illustrate a process in which UE 115 may use one or more SRIs included in a control message to select corresponding SRS resources from a default resource set (e.g., a resource set with a smallest identifier).

[0112] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0, resource set 1, or both), one or more SRS resources corresponding to each resource set (e.g., resource set 0 corresponds to SRS resources 0 and 1, and resource set 1 corresponds to SRS resources 2 and 3), wherein the SRS configuration indicates a mapping between each SRS resource and a bit sequence. In some cases, as shown in resource diagram 400, the SRS configuration may configure the UE 115 to select a default resource set, such as resource set 0, which may be the resource set with the lowest or highest identifier. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, an SRI value of 0 may indicate SRS resource 0 in the default resource set, while an SRI value of 1 may indicate SRS resource 1 in the default resource set. The UE 115 may select an SRS resource for codebook use based on the SRI and the mapped resource set.

[0113] In some examples, the control message may include one or more identifiers for the corresponding resource set. UE 115 may select a default resource set (e.g., the resource set with the smallest identifier) ​​from the multiple resource sets indicated by the sounding reference signal configuration. In the depicted example, the default resource set may be resource set 0. UE 115 may use the one or more SRSs included in the control message to select corresponding SRS resources (e.g., codebook usage) for transmitting SRS transmissions. UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0114] For example, resource diagram 400 may illustrate an example process when UE 115 has two transmit antennas and eight receive antennas and is configured with two resource sets and two SRS resources in each resource set, where one of the SRS resources is used for codebook use and the SRI field is a single bit. Each resource set may be associated with an antenna port. For example, resource set 0 may use antenna port 0, while resource set 1 may use antenna port 1. UE 115 may use one SRS resource for codebook use based on a one-bit indicator (e.g., SRI is 0 or SRI is 1). For example, the control message may be a DCI message with an SRI field, where an SRI field with a value of 0 indicates SRS resource 0 of a default resource set, while an SRI field with a value of 1 indicates SRS resource 1 of a default resource set. UE 115 may transmit SRS in the SRS resource indicated by the SRI field in the control message.

[0115] Figure 5 An example of a resource map 500 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 500 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, the resource map 400, or a combination thereof. The resource map 500 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2 For example, resource diagram 500 may illustrate a process in which base station 105 may include an SRS set indicator and one or more SRIs in a control message to UE 115.

[0116] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0, resource set 1, or both), one or more SRS resources corresponding to each resource set (e.g., resource set 0 corresponds to SRS resources 0 and 1, and resource set 1 corresponds to SRS resources 2 and 3), wherein the SRS configuration indicates a mapping between each SRS resource and a bit sequence. In some cases, as shown in resource diagram 500, the UE 115 may select a resource set, such as resource set 0 or resource set 1, based on a resource set indicator 505 in the SRS configuration. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, an SRI value of 0 may indicate SRS resource 0 in the indicated resource set, such as resource set 0, while an SRI value of 1 may indicate SRS resource 1 in the indicated resource set. The UE 115 may select an SRS resource for codebook use based on the SRI and the resource set.

[0117] In some examples, the control message may include an indication of a resource set indicator 505 and an SRI 510. The resource set indicator 505 may be a single bit, where a value of 0 indicates that the UE 115 uses a default resource set (e.g., the resource set with the lowest or highest identifier), while a value of 1 indicates that the UE uses resource set 1. The SRI 510 may be any number of bits, where a value of 0 indicates that the UE uses the first SRS resource in the default resource set (e.g., SRS resource 0), while a bit value greater than 0 indicates an SRS resource in the set (e.g., SRS resource 1 through SRS resource 3). The UE 115 may use one or more SRIs 510 and corresponding resource set identifiers 505 included in the control message to select an SRS resource for SRS transmission (e.g., codebook usage). The UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0118] For example, resource diagram 500 may illustrate an example process when UE 115 has two transmit antennas and eight receive antennas and is configured with two resource sets and two SRS resources in each resource set, wherein one of the SRS resources is used for codebook use and the SRI field is a single bit. UE 115 may use one SRS resource for codebook use based on a one-bit indicator (e.g., SRI is 0 or SRI is 1). For example, the control message may be a DCI message having a resource set identifier field and an SRI field, wherein a resource set indicator 505 having a value of 0 indicates resource set 0, and a resource set indicator 505 having a value of 1 indicates resource set 1. Additionally, an SRI field having a value of 0 indicates SRS resource 0, an SRI field having a value of 1 indicates SRS resource 1, an SRI field having a value of 2 indicates SRS resource 2, and an SRI field having a value of 3 indicates SRS resource 3. UE 115 may transmit an SRS in the SRS resource indicated by the SRI field in the control message.

[0119] Figure 6 An example of a resource map 600 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 600 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, the resource map 400, the resource map 500, or a combination thereof. The resource map 600 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2For example, resource diagram 600 may illustrate a process in which base station 105 may construct a lookup table to map one or more SRIs to each SRS resource in a resource set based on a bit sequence included in a control message to UE 115 .

[0120] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0), one or more SRS resources corresponding to each resource set (e.g., SRS resources 0 to SRS resources 7 corresponding to resource set 0), wherein the SRS configuration indicates a mapping between each SRS resource and a bit sequence. In some cases, as shown in resource diagram 600, the base station 105 may construct a lookup table and then indicate the lookup table to the UE 115 in the SRS configuration. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, if the SRI has values ​​of 000 to 111, respectively, the UE 115 may select one of SRS resources 0 to SRS resources 7. The UE 115 may select an SRS resource for codebook use based on the SRI and the resource set.

[0121] In some examples, the base station 105 may construct a lookup table to map the SRI in the control message to each SRS resource in a single resource set (such as resource set 0) (e.g., regardless of the number of SRS resources in the resource set). For example, the SRI may be a bit sequence of size log2R bits, where R is the number of SRS resources in the resource set. For a UE 115 having one transmit antenna and eight receive antennas, the UE 115 may select an SRS resource from a single resource set having eight SRS resources based on the SRI having three bits. As shown in resource diagram 600, the control message may indicate each of SRS resources 0 to SRS resource 7 with a three-bit value. If there are more SRS resources in the resource set, the base station 105 may indicate the SRI to the UE 115 with a bit sequence size greater than three. The UE 115 may use one or more SRIs included in the control message to select an SRS resource for SRS transmission (e.g., codebook usage). The UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0122] For example, resource diagram 600 may illustrate an example process when UE 115 has one transmit antenna and eight receive antennas and is configured with one resource set with eight SRS resource sets, where one of the SRS resources is used for codebook use and the SRI field is three bits. UE 115 may use one SRS resource for codebook use based on a three-bit indicator (e.g., SRI 000 to SRI 111). For example, the control message may be a DCI message with an SRI field, where an SRI field with a value of 000 indicates SRS resource 0, an SRI field with a value of 001 indicates SRS resource 1, and so on. UE 115 may transmit SRS in the SRS resource indicated by the SRI field in the control message.

[0123] Figure 7 An example of a resource map 700 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 700 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, the resource map 400 through the resource map 600, or a combination thereof. The resource map 700 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2 For example, resource diagram 700 may illustrate a process in which base station 105 may construct a lookup table to map one or more SRIs to each SRS resource in a plurality of resource sets based on a bit sequence included in a control message to UE 115.

[0124] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0, resource set 1, or both), one or more SRS resources corresponding to each resource set (e.g., SRS resources 0 through SRS resources 3 correspond to SRS resource set 0, and SRS resources 4 through SRS resources 7 correspond to SRS resource set 1), where the SRS configuration indicates a mapping between each SRS resource and a bit sequence. In some cases, as shown in resource diagram 700, the base station 105 may construct a lookup table and then indicate the lookup table to the UE 115 in the SRS configuration. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, if the SRI has values ​​of 000 through 111, respectively, the UE 115 may select one of SRS resources 0 through SRS resource 7. The UE 115 may select an SRS resource for codebook use based on the SRI and the resource set.

[0125] In some examples, the base station 105 may construct a lookup table to map the SRI in the control message to each SRS resource in multiple resource sets (such as resource set 0 and resource set 1) (e.g., regardless of the number of SRS resources in the resource set). For example, the SRI may be a bit sequence of size log2R bits, where R is the number of SRS resources in the resource set. For a UE 115 with one transmit antenna and eight receive antennas, the UE 115 may select an SRS resource from one of two resource sets, each with four SRS resources, based on the SRI having three bits. As shown in resource diagram 700, the control message may indicate each of SRS resources 0 to SRS resource 7 using a three-bit value. If there are more SRS resources in the resource set, the base station 105 may indicate the SRI to the UE 115 using a bit sequence size greater than three. The UE 115 may use one or more SRS resources included in the control message to select an SRS resource for transmitting an SRS transmission (e.g., codebook usage). The UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0126] For example, resource diagram 700 may illustrate an example process when UE 115 has one transmit antenna and eight receive antennas and is configured with two resource sets, each with four SRS resource sets, where one of the SRS resources is used for codebook use and the SRI field is three bits. Each resource set may be associated with an antenna port. For example, resource set 0 may use antenna port 0, while resource set 1 may use antenna port 1. UE 115 may use one SRS resource for codebook use based on a three-bit indicator (e.g., SRI of 000 to SRI of 111) independent of the number of resource sets. For example, the control message may be a DCI message with an SRI field, where an SRI field with a value of 000 indicates SRS resource 0, an SRI field with a value of 001 indicates SRS resource 1, and so on. UE 115 may transmit SRS in the SRS resource indicated by the SRI field in the control message.

[0127] Figure 8 An example of a resource map 800 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 800 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, the resource map 400 through the resource map 700, or a combination thereof. The resource map 800 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2For example, resource diagram 800 may illustrate a process in which UE 115 may select SRS resources from a static virtual resource set 805 using one or more SRIs included in a control message, which may be indicated in control signaling from base station 105.

[0128] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0, resource set 1, or both), one or more SRS resources corresponding to each resource set (e.g., SRS resources 0 and 1 corresponding to SRS resource set 0, and SRS resources 2 and 3 corresponding to SRS resource set 1), wherein the SRS configuration indicates a mapping between each SRS resource and a bit sequence. The UE 115 may perform a static downselection method to determine a static virtual resource set 805, which may include SRS resources from resource set 0 and resource set 1 (e.g., SRS resource 1 from resource set 0 and SRS resource 2 from resource set 1). In some cases, as shown in the resource diagram 800, the UE 115 may downselect SRS resource 1 from resource set 0 and SRS resource 2 from resource set 1 for the static virtual resource set 805 based on control signaling. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, an SRI value of 0 may indicate SRS resource 1 in the static virtual resource set 805, while an SRI value of 1 may indicate SRS resource 2 in the static virtual resource set 805. The UE 115 may select an SRS resource for codebook use based on the SRI and the static virtual resource set 805.

[0129] In some examples, UE 115 may perform a static downselection method to reduce signaling overhead from SRI transmission. For example, UE 115 may use a static virtual resource set 805 (e.g., which may be preset) based on control signaling, which includes a portion of the total SRS resources available to UE 115, such as SRS resource 1 and SRS resource 2. That is, in some cases, UE 115 may receive an SRS configuration from base station 105 (e.g., via RRC signaling or MAC-CE) and may use the SRS configuration to downselect static virtual resource set 805. UE 115 may use the SRS configuration included in the control message received from base station 105 to select an SRS resource from static virtual resource set 805. Resource diagram 800 may illustrate an example process when UE 115 has two transmit antennas and eight receive antennas and receives two resource sets with two SRS resources in each resource set. The SRI may be a single bit with a value of 0 to indicate SRS resource 1 of static virtual resource set 805 or a value of 1 to indicate SRS resource 2 of static virtual resource set 805. The UE 115 may use one or more SRIs included in the control message to select an SRS resource (e.g., codebook usage) for SRS transmission from the static virtual resource set 805. The UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0130] For example, resource diagram 800 may illustrate an example process when UE 115 is configured with a static virtual resource set 805 that includes two SRS resources (e.g., SRS resource 1 from resource set 0 and SRS resource 2 from resource set 1), each SRS resource from a different resource set, with two SRS resources in each resource set. In some cases, one of the SRS resources in static virtual resource set 805 is used for codebook use, and the SRI field may be a single bit. Each resource set may be associated with an antenna port. For example, resource set 0 may use antenna port 0, while resource set 1 may use antenna port 1. UE 115 may use one SRS resource for codebook use based on a one-bit indicator (e.g., SRI of 0 or SRI of 1). For example, the control message may be a DCI message with an SRI field, where an SRI field with a value of 0 indicates SRS resource 1, and an SRI field with a value of 1 indicates SRS resource 2. UE 115 may transmit SRS in the SRS resource indicated by the SRI field in the control message.

[0131] Figure 9An example of a resource map 900 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, the resource map 900 can implement aspects of the wireless communication system 100, the wireless communication system 200, the resource map 300, the resource map 400 through the resource map 800, or a combination thereof. The resource map 900 can be implemented by the UE 115 and the base station 105 in SRS transmissions (e.g., combined codebook-based SRS transmissions and one or more antenna switching SRS transmissions), as described with reference to FIG. Figure 1 and Figure 2 For example, resource diagram 900 may illustrate a process in which UE 115 may use one or more SRIs included in a control message to select SRS resources from a dynamic virtual resource set based on a slot index.

[0132] In some cases, the base station 105 may transmit an SRS configuration indicating one or more resource sets (e.g., resource set 0, resource set 1, or both), one or more SRS resources corresponding to each resource set (e.g., SRS resources 0 and 1 correspond to SRS resource set 0, and SRS resources 2 and 3 correspond to SRS resource set 1), wherein the SRS configuration indicates a mapping between each SRS resource and a bit sequence. The UE 115 may perform a round-robin down-selection method to determine a dynamic virtual resource set 905, which may include SRS resources from resource set 0, resource set 1, or both (e.g., SRS resource 0 from resource set 0 and SRS resource 3 from resource set 1). In some cases, as shown in the resource diagram 900, the UE 115 may down-select SRS resource 0 from resource set 0 and SRS resource 3 from resource set 1 for the dynamic virtual resource set 905 based on the time slot index. The base station 105 may transmit a control message to the UE 115 (e.g., via a DCI message) that includes a bit sequence, which may be referred to as an SRI, to indicate the SRS resources based on the mapping. For example, an SRI value of 0 may indicate SRS resource 0 in the dynamic virtual resource set 905, while an SRI value of 1 may indicate SRS resource 3 in the dynamic virtual resource set 905. The UE 115 may select an SRS resource for codebook use based on the SRI and the dynamic virtual resource set 905.

[0133] In some examples, the UE 115 may perform a round-robin down-selection method to reduce the signaling overhead from the SRS transmission. For example, the UE 115 may use a dynamic virtual resource set 905 based on a slot index that includes a portion of the total SRS resources available to the UE 115, such as SRS resource 1 and SRS resource 3. The UE 115 may determine which SRS resources are included in the dynamic virtual resource set 905 using the index of the slot in which the base station 105 sends a control message including an uplink grant, the index of the slot in which the UE 115 sends the PUSCH indicated in the uplink grant, or both. The UE 115 may divide the SRS resources into possible group candidates (e.g., 6 group candidates). The UE 115 may select the SRS resources based on the modulation operator mod(slot) and the modulation operator mod(slot) of the UE 115. index , subset number ) is applied to possible set combinations (e.g., subset number =C4 2 =6mod(slot index , 6)=2), a group is selected from the candidates (e.g., group III including SRS resource 0 and SRS resource 3). Although a modulation operator is shown in resource diagram 900, UE 115 can determine the SRS resources in dynamic virtual resource set 905 based on any operation using a slot index or other parameters for communication between UE 115 and base station 105.

[0134] Resource diagram 900 may illustrate an example process when UE 115 has two transmit antennas and eight receive antennas and receives two resource sets with two SRS resources in each resource set. The SRI may be a single bit with a value of 0 to indicate SRS resource 1 or a value of 1 to indicate SRS resource 2. UE 115 may use one or more SRIs included in the control message to select an SRS resource (e.g., codebook usage) from the dynamic virtual resource set 905 for SRS transmission. UE 115 may use one or more other SRS resources for antenna switching operations (e.g., downlink CSI usage).

[0135] For example, resource diagram 900 may illustrate an example process when UE 115 is configured with a dynamic virtual resource set 905 that includes two SRS resources (e.g., SRS resource 0 from resource set 0 and SRS resource 3 from resource set 1, based on a slot index). In some cases, one of the SRS resources in the dynamic virtual resource set 805 is used for codebook use, and the SRI field may be a single bit. Each resource set may be associated with an antenna port. For example, resource set 0 may use antenna port 0, while resource set 1 may use antenna port 1. UE 115 may use one SRS resource for codebook use based on a one-bit indicator (e.g., SRI of 0 or SRI of 1). For example, the control message may be a DCI message with an SRI field, where an SRI field with a value of 0 indicates SRS resource 0, and an SRI field with a value of 1 indicates SRS resource 3. UE 115 may send SRS in the SRS resource indicated by the SRI field in the control message.

[0136] Figure 10 An example of a process flow 1000 supporting techniques for mapping SRS resources according to aspects of the present disclosure is shown. In some examples, process flow 1000 can implement aspects of wireless communication system 100, wireless communication system 200, resource map 300, resource map 400 through resource map 900, or a combination thereof. Process flow 1000 can illustrate an example of a base station 105 (such as base station 105-b) configuring a mapping between SRS resources and a bit sequence (which can be referred to as an SRI) for a UE 115 (such as UE 115-b), and the UE 115 transmitting an SRS during the SRS resource based on receiving an indication of a particular bit sequence. Alternative examples below can be implemented in which some of the processes are performed in a different order than described or not performed at all. In some cases, the process can include other features not mentioned below, or additional processes can be added.

[0137] At 1005, UE 115-b may determine that the number of transmit antennas for antenna switching operations exceeds the number of receive antennas. UE 115-b may include in a capabilities message to base station 105b the number of transmit antennas, the number of receive antennas, the number of ports supported for uplink transmission at UE 115-b, or a combination thereof. At 1010, UE 115-b may send a capabilities message if the number of transmit antennas exceeds the number of receive antennas. In some examples, the number of transmit antennas and the number of ports may be the same.

[0138] At 1015, the base station 105-b may determine an SRS configuration based on a capability message from the UE 115-b, wherein the SRS configuration indicates a mapping between one or more SRS resources and a corresponding bit sequence (which may be referred to as an SRI). The bit sequence may be a single bit or any number of bits (e.g., three bits). Based on the capability message, the base station 105-b may determine the number of resource sets and the number of SRS resources to use for SRS sounding and SRS codebook-based sounding for antenna switching, and may determine a mapping between the SRI bit sequence and the SRS resources.

[0139] At 1020, the base station 105-b may send an SRS configuration to the UE 115-b. In some examples, the configuration may include an indication of one or more resource sets. For example, the SRS configuration may indicate a single resource set or multiple resource sets. In some cases, the SRS configuration may indicate a virtual resource set (e.g., a static virtual resource set) that includes SRS resources from multiple resource sets. In some other cases, the SRS configuration may indicate a virtual resource set (e.g., a dynamic virtual resource set) that includes SRS resources based on a time slot index. The SRS configuration may indicate which mapping technique between the SRS bit sequence and the SRS resources is being applied, such as a reference to a time slot index. Figures 4 to 9 Exemplary mapping techniques are discussed.

[0140] At 1025, base station 105-b may send a control message including one or more SRIs that indicate one or more SRS resources based on a mapping between the SRIs and the SRS resources. In some examples, the control message may include multiple identifiers for corresponding resource sets. The one or more SRS resources may be included in at least one of the resource sets. For example, the SRS resources may be included in the resource set with the highest or lowest identifier. In some examples, the control message may include an indication of a resource set in a plurality of resource sets (e.g., a set indicator) and an indication of the SRS (e.g., an SRI). If the set indicator has a zero value, UE 115-b may use one or more SRS resources from a first resource set in the plurality of resource sets. If the set indicator has a non-zero value, UE 115-b may use one or more SRS resources from a resource set indicated by the set indicator. If the SRI has a zero value, UE 115-b may use a first SRS resource from a resource set in the plurality of resource sets. If the SRI has a non-zero value, UE 115-b may use an SRS resource from a resource set indicated by the SRI.

[0141] At 1030, UE 115-b may map one or more SRIs or bit sequences to one or more SRS resources for SRS transmission based on the SRS configuration. For example, if the SRI is one bit, the SRI may have a value of 0 or 1, which may correspond to an SRS resource index in one or more resource sets. In some other examples, if the SRI is three bits, the SRI may have a value of 000 to 111, which may correspond to an SRS resource index in one or more resource sets. At 1035, UE 115-b may transmit the SRS in the one or more SRS resources to base station 105-b.

[0142] Figure 11 A block diagram 1100 is shown of a device 1105 supporting techniques for mapping SRS resources according to aspects of the present disclosure. The device 1105 may be an example of aspects of the UE 115 as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communication manager 1120. The device 1105 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0143] The receiver 1110 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. The information may be passed to other components of the device 1105. The receiver 1110 may utilize a single antenna or a set of multiple antennas.

[0144] The transmitter 1115 may provide means for transmitting signals generated by other components of the device 1105. For example, the transmitter 1115 may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. In some examples, the transmitter 1115 may be co-located with the receiver 1110 in the transceiver module. The transmitter 1115 may utilize a single antenna or a set of multiple antennas.

[0145] The communication manager 1120, the receiver 1110, the transmitter 1115, or various combinations thereof, or various components thereof, may be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, the communication manager 1120, the receiver 1110, the transmitter 1115, or various combinations thereof, or components thereof, may support methods for performing one or more of the functions described herein.

[0146] In some examples, the communication manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof can be implemented in hardware (e.g., in a communication management circuit). The hardware can include a processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured as or otherwise supports components for performing the functions described in this disclosure. In some examples, the processor and a memory coupled to the processor can be configured (e.g., by the processor executing instructions stored in the memory) to perform one or more of the functions described herein.

[0147] Additionally or alternatively, in some examples, the communication manager 1120, receiver 1110, transmitter 1115, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 1120, receiver 1110, transmitter 1115, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a central processing unit (CPU), an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., components configured or otherwise supported for performing the functions described in this disclosure).

[0148] In some examples, communication manager 1120 can be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with receiver 1110, transmitter 1115, or both. For example, communication manager 1120 can receive information from receiver 1110, transmit information to transmitter 1115, or integrate with receiver 1110, transmitter 1115, or both to receive information, transmit information, or perform various other operations as described herein.

[0149] The communication manager 1120 may support wireless communications at a UE according to examples disclosed herein. For example, the communication manager 1120 may be configured to, or otherwise support, a component for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The communication manager 1120 may be configured to, or otherwise support, a component for receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The communication manager 1120 may be configured to, or otherwise support, a component for receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The communication manager 1120 may be configured or otherwise support means for transmitting the first SRS in the first SRS resource based on the control message.

[0150] By including or configuring a communication manager 1120 according to the examples described herein, a device 1105 (e.g., a processor controlling or otherwise coupled to a receiver 1110, a transmitter 1115, a communication manager 1120, or a combination thereof) can support techniques for more efficiently utilizing communication resources (e.g., SRS resources).

[0151] Figure 12 A block diagram 1200 is shown of a device 1205 supporting techniques for mapping SRS resources according to aspects of the present disclosure. The device 1205 may be an example of aspects of the device 1105 or UE 115 as described herein. The device 1205 may include a receiver 1210, a transmitter 1215, and a communication manager 1220. The device 1205 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0152] The receiver 1210 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. The information may be passed to other components of the device 1205. The receiver 1210 may utilize a single antenna or a set of multiple antennas.

[0153] The transmitter 1215 may provide means for transmitting signals generated by other components of the device 1205. For example, the transmitter 1215 may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. In some examples, the transmitter 1215 may be co-located with the receiver 1210 in the transceiver module. The transmitter 1215 may utilize a single antenna or a set of multiple antennas.

[0154] Device 1205 or its various components can be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, communication manager 1220 can include capability component 1225, mapping component 1230, bit sequence component 1235, SRS component 1240, or any combination thereof. Communication manager 1220 can be an example of various aspects of communication manager 1120 as described herein. In some examples, communication manager 1220 or its various components can be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with receiver 1210, transmitter 1215, or both. For example, communication manager 1220 can receive information from receiver 1210, send information to transmitter 1215, or be integrated with receiver 1210, transmitter 1215, or both to receive information, send information, or perform various other operations as described herein.

[0155] The communication manager 1220 can support wireless communications at a UE according to the examples disclosed herein. The capability component 1225 can be configured to or otherwise support means for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The mapping component 1230 can be configured to or otherwise support means for receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The bit sequence component 1235 can be configured to or otherwise support means for receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The SRS component 1240 may be configured or otherwise support means for transmitting a first SRS in a first SRS resource based on a control message.

[0156] Figure 13 A block diagram 1300 of a communication manager 1320 supporting techniques for mapping SRS resources in accordance with aspects of the present disclosure is shown. The communication manager 1320 may be an example of aspects of the communication manager 1120, the communication manager 1220, or both described herein. The communication manager 1320 or its various components may be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, the communication manager 1320 may include a capability component 1325, a mapping component 1330, a bit sequence component 1335, an SRS component 1340, an identifier component 1345, an indicator component 1350, a capability component 1355, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses).

[0157] The communication manager 1320 can support wireless communications at a UE according to examples disclosed herein. The capability component 1325 can be configured to or otherwise support means for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The mapping component 1330 can be configured to or otherwise support means for receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The bit sequence component 1335 can be configured to or otherwise support means for receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The SRS component 1340 may be configured or otherwise support means for transmitting a first SRS in a first SRS resource based on a control message.

[0158] In some examples, to support receiving the control message, identifier component 1345 can be configured to or otherwise support means for receiving an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers. In some examples, the first identifier is a highest or lowest identifier in the set of multiple identifiers corresponding to the set of multiple resource sets.

[0159] In some examples, to support receiving an SRS configuration, the identifier component 1350 can be configured as or otherwise support components for receiving an SRS configuration indicating a set of multiple resource sets, wherein the control message indicates a first resource set in the set of multiple resource sets that is associated with a subset of the set of multiple SRS resources and indicates a first SRS resource in the subset of the set of multiple SRS resources.

[0160] In some examples, to support receiving the control message, identifier component 1350 can be configured as or otherwise support means for receiving a control message including a set indicator having a zero value, the set indicator indicating a first resource set in the set of the multiple resource sets.

[0161] In some examples, to support receiving the control message, identifier component 1350 can be configured as or otherwise support means for receiving a control message including a set indicator having a non-zero value indicating a first resource set in the set of the multiple resource sets.

[0162] In some examples, to support receiving the control message, identifier component 1350 can be configured or otherwise support means for receiving a control message including a resource indicator having a zero value, the set indicator indicating a first SRS resource in a subset of the set of the plurality of SRS resources.

[0163] In some examples, to support receiving the control message, identifier component 1350 can be configured as or otherwise support means for receiving a control message including a resource indicator having a non-zero value, the set indicator indicating a first SRS resource in a subset of the set of the plurality of SRS resources.

[0164] In some examples, to support receiving an SRS configuration, capability component 1355 can be configured as or otherwise support components for receiving an SRS configuration indicating a single resource set associated with the set of multiple SRS resources based on the capability message, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0165] In some examples, capability component 1355 can be configured to or otherwise support components for receiving an SRS configuration indicating a set of multiple resource sets based on the capability message, each SRS resource in the set of multiple SRS resources being associated with a corresponding resource set in the set of multiple resource sets, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0166] In some examples, to support receiving the SRS configuration, mapping component 1330 can be configured as or otherwise support components for receiving an SRS configuration indicating a virtual resource set comprising a subset of the set of multiple SRS resources, wherein the virtual resource set comprises a first SRS resource from the first resource set and a second SRS resource from the second resource set.

[0167] In some examples, to support receiving the SRS configuration, mapping component 1330 can be configured as or otherwise support components for receiving an SRS configuration indicating a virtual resource set comprising a subset of the set of multiple SRS resources, wherein based on a time slot index corresponding to the control message, the first SRS resource is included in the subset of the set of multiple SRS resources.

[0168] In some examples, to support receiving the control message, identifier component 1345 can be configured as or otherwise support means for receiving a control message indicating a resource set identifier of a first resource set corresponding to the set of multiple SRS resources.

[0169] In some examples, the first bit sequence includes a single bit.In some examples, the first number of one or more transmit antennas and the third number of one or more ports are the same.

[0170] Figure 14 A diagram of a system 1400 including a device 1405 supporting techniques for mapping SRS resources in accordance with various aspects of the present disclosure is shown. Device 1405 may be an example of or include components of device 1105, device 1205, or UE 115 described herein. Device 1405 may wirelessly communicate with one or more base stations 105, UE 115, or any combination thereof. Device 1405 may include components for two-way voice and data communications, including components for sending and receiving communications, such as a communications manager 1420, an input / output (I / O) controller 1410, a transceiver 1415, an antenna 1425, a memory 1430, code 1435, and a processor 1440. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1445).

[0171] I / O controller 1410 can manage input and output signals for device 1405. I / O controller 1410 can also manage peripheral devices that are not integrated into device 1405. In some cases, I / O controller 1410 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 1410 can utilize a computer such as , or another known operating system. Additionally or alternatively, I / O controller 1410 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 1410 may be implemented as part of a processor, such as processor 1440. In some cases, a user may interact with device 1405 via I / O controller 1410 or via hardware components controlled by I / O controller 1410.

[0172] In some cases, the device 1405 may include a single antenna 1425. However, in some other cases, the device 1405 may have more than one antenna 1425, which may be capable of transmitting or receiving multiple wireless transmissions simultaneously. As described herein, the transceiver 1415 can communicate bidirectionally via one or more antennas 1425, a wired or wireless link. For example, the transceiver 1415 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. The transceiver 1415 can also include a modem to modulate packets, provide the modulated packets to one or more antennas 1425 for transmission, and demodulate packets received from the one or more antennas 1425. The transceiver 1415 or the transceiver 1415 and the one or more antennas 1425 can be examples of the transmitter 1115, the transmitter 1215, the receiver 1110, the receiver 1210, or any combination thereof, or components thereof, as described herein.

[0173] The memory 1430 may include random access memory (RAM) and read-only memory (ROM). The memory 1430 may store computer-readable, computer-executable code 1435 including instructions that, when executed by the processor 1440, cause the device 1405 to perform the various functions described herein. The code 1435 may be stored in a non-transitory computer-readable medium (such as system memory or another type of memory). In some cases, the code 1435 may not be directly executable by the processor 1440, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein. In some cases, the memory 1430 may include, among other things, an I / O system (BIOS), which may control basic hardware or software operations, such as interacting with peripheral components or devices.

[0174] The processor 1440 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 1440 may be configured to operate the memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1440. The processor 1440 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1430) to cause the device 1405 to perform various functions (e.g., functions or tasks supporting a technique for mapping SRS resources). For example, the device 1405 or a component of the device 1405 may include a processor 1440 and a memory 1430 coupled to the processor 1440, the processor 1440 and the memory 1430 being configured to perform the various functions described herein.

[0175] The communication manager 1420 may support wireless communications at a UE according to examples disclosed herein. For example, the communication manager 1420 may be configured to or otherwise support means for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The communication manager 1420 may be configured to or otherwise support means for receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The communication manager 1420 may be configured to or otherwise support means for receiving a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The communication manager 1420 may be configured or otherwise support means for transmitting the first SRS in the first SRS resource based on the control message.

[0176] By including or configuring a communication manager 1420 according to examples described herein, the device 1405 can support techniques for reducing latency and more efficiently utilizing communication resources (eg, SRS resources) due to reducing the transmission of SRIs.

[0177] In some examples, the communication manager 1420 can be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with the transceiver 1415, one or more antennas 1425, or any combination thereof. Although the communication manager 1420 is shown as a separate component, in some examples, one or more functions described with reference to the communication manager 1420 can be supported or performed by the processor 1440, the memory 1430, the code 1435, or any combination thereof. For example, the code 1435 can include instructions executable by the processor 1440 to cause the device 1405 to perform various aspects of the techniques for mapping SRS resources as described herein, or the processor 1440 and the memory 1430 can be otherwise configured to perform or support such operations.

[0178] Figure 15 A block diagram 1500 is shown of a device 1505 supporting techniques for mapping SRS resources according to aspects of the present disclosure. The device 1505 can be an example of aspects of the base station 105 as described herein. The device 1505 can include a receiver 1510, a transmitter 1515, and a communication manager 1520. The device 1505 can also include a processor. Each of these components can communicate with each other (e.g., via one or more buses).

[0179] The receiver 1510 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. The information may be passed to other components of the device 1505. The receiver 1510 may utilize a single antenna or a set of multiple antennas.

[0180] The transmitter 1515 may provide a means for transmitting signals generated by other components of the device 1505. For example, the transmitter 1515 may transmit information such as packets associated with various information channels (e.g., a control channel, a data channel, an information channel related to a technique for mapping SRS resources), user data, control information, or any combination thereof. In some examples, the transmitter 1515 may be co-located with the receiver 1510 in the transceiver module. The transmitter 1515 may utilize a single antenna or a set of multiple antennas.

[0181] The communication manager 1520, the receiver 1510, the transmitter 1515, or various combinations thereof, or various components thereof, may be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, the communication manager 1520, the receiver 1510, the transmitter 1515, or various combinations thereof, or components thereof, may support methods for performing one or more of the functions described herein.

[0182] In some examples, the communication manager 1520, the receiver 1510, the transmitter 1515, or various combinations or components thereof can be implemented in hardware (e.g., in a communication management circuit). The hardware can include a processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured as or otherwise supports components for performing the functions described in this disclosure. In some examples, a processor and a memory coupled to the processor can be configured (e.g., by the processor executing instructions stored in the memory) to perform one or more of the functions described herein.

[0183] Additionally or alternatively, in some examples, the communication manager 1520, receiver 1510, transmitter 1515, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 1520, receiver 1510, transmitter 1515, or various combinations or components thereof may be performed by a general-purpose processor, DSP, CPU, ASIC, FPGA, or any combination of these or other programmable logic devices (e.g., components configured or otherwise supported for performing the functions described in this disclosure).

[0184] In some examples, communication manager 1520 can be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with receiver 1510, transmitter 1515, or both. For example, communication manager 1520 can receive information from receiver 1510, transmit information to transmitter 1515, or integrate with receiver 1510, transmitter 1515, or both to receive information, transmit information, or perform various other operations as described herein.

[0185] The communication manager 1520 may support wireless communications at a base station according to examples disclosed herein. For example, the communication manager 1520 may be configured to or otherwise support components for receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The communication manager 1520 may be configured to or otherwise support components for sending an SRS configuration to the UE based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The communication manager 1520 may be configured to or otherwise support components for sending a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The communication manager 1520 may be configured or otherwise support means for receiving a first SRS in a first SRS resource based on the control message.

[0186] By including or configuring a communication manager 1520 according to the examples described herein, the device 1505 (e.g., a processor controlling or otherwise coupled to the receiver 1510, the transmitter 1515, the communication manager 1520, or a combination thereof) can support techniques for more efficiently utilizing communication resources (e.g., SRS resources) by combining SRS resources used for codebook-based SRS transmissions with SRS transmissions used for antenna switching operations.

[0187] Figure 16 A block diagram 1600 is shown of a device 1605 supporting techniques for mapping SRS resources according to aspects of the present disclosure. The device 1605 can be an example of aspects of the device 1505 or base station 105 as described herein. The device 1605 can include a receiver 1610, a transmitter 1615, and a communication manager 1620. The device 1605 can also include a processor. Each of these components can communicate with each other (e.g., via one or more buses).

[0188] The receiver 1610 may provide means for receiving information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. The information may be passed to other components of the device 1605. The receiver 1610 may utilize a single antenna or a group of multiple antennas.

[0189] The transmitter 1615 may provide means for transmitting signals generated by other components of the device 1605. For example, the transmitter 1615 may transmit information such as packets associated with various information channels (e.g., control channels, data channels, information channels related to techniques for mapping SRS resources), user data, control information, or any combination thereof. In some examples, the transmitter 1615 may be co-located with the receiver 1610 in the transceiver module. The transmitter 1615 may utilize a single antenna or a set of multiple antennas.

[0190] Device 1605 or its various components can be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, communication manager 1620 can include capability component 1625, mapping component 1630, bit sequence component 1635, SRS component 1640, or any combination thereof. Communication manager 1620 can be an example of various aspects of communication manager 1520 as described herein. In some examples, communication manager 1620 or its various components can be configured to use or otherwise cooperate with receiver 1610, transmitter 1615, or both to perform various operations (e.g., receive, monitor, transmit). For example, communication manager 1620 can receive information from receiver 1610, send information to transmitter 1615, or be integrated with receiver 1610, transmitter 1615, or both to receive information, send information, or perform various other operations as described herein.

[0191] The communication manager 1620 can support wireless communications at a base station according to the examples disclosed herein. The capability component 1625 can be configured to or otherwise support means for receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The mapping component 1630 can be configured to or otherwise support means for sending an SRS configuration to the UE based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The bit sequence component 1635 can be configured to or otherwise support means for sending a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The SRS component 1640 may be configured or otherwise support means for receiving a first SRS in a first SRS resource based on the control message.

[0192] Figure 17 Block diagram 1700 of a communication manager 1720 supporting techniques for mapping SRS resources in accordance with aspects of the present disclosure is shown. The communication manager 1720 may be an example of aspects of the communication manager 1520, the communication manager 1620, or both described herein. The communication manager 1720 or its various components may be examples of components for performing various aspects of the techniques for mapping SRS resources as described herein. For example, the communication manager 1720 may include a capability component 1725, a mapping component 1730, a bit sequence component 1735, an SRS component 1740, an identifier component 1745, an indicator component 1750, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses).

[0193] The communication manager 1720 can support wireless communications at a base station according to the examples disclosed herein. The capability component 1725 can be configured to or otherwise support means for receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The mapping component 1730 can be configured to or otherwise support means for sending an SRS configuration to the UE based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The bit sequence component 1735 can be configured to or otherwise support means for sending a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The SRS component 1740 may be configured or otherwise support means for receiving a first SRS in a first SRS resource based on the control message.

[0194] In some examples, to support sending the control message, identifier component 1745 can be configured to or otherwise support means for sending an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers. In some examples, the first identifier is a highest or lowest identifier in the set of multiple identifiers corresponding to the set of multiple resource sets.

[0195] In some examples, to support sending an SRS configuration, identifier component 1750 can be configured as or otherwise support components for sending an SRS configuration indicating a set of multiple resource sets, wherein the control message indicates a first resource set in the set of multiple resource sets that is associated with a subset of the set of multiple SRS resources and indicates a first SRS resource in the subset of the set of multiple SRS resources.

[0196] In some examples, to support sending the control message, identifier component 1750 can be configured or otherwise support means for sending a control message including a set indicator having a zero value, the set indicator indicating a first resource set in the set of the plurality of resource sets. In some examples, to support sending the control message, identifier component 1750 can be configured or otherwise support means for sending a control message including a set indicator having a non-zero value, the set indicator indicating a first resource set in the set of the plurality of resource sets.

[0197] In some examples, to support sending the control message, identifier component 1750 can be configured to or otherwise support means for sending a control message including a resource indicator having a zero value, the set indicator indicating a first SRS resource in the subset of the set of the plurality of SRS resources. In some examples, to support sending the control message, identifier component 1750 can be configured to or otherwise support means for sending a control message including a resource indicator having a non-zero value, the set indicator indicating a first SRS resource in the subset of the set of the plurality of SRS resources.

[0198] In some examples, to support sending an SRS configuration, capability component 1725 can be configured as or otherwise support components for sending an SRS configuration indicating a single resource set associated with the set of multiple SRS resources based on the capability message, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0199] In some examples, capability component 1725 can be configured as or otherwise support components for sending an SRS configuration indicating a set of multiple resource sets based on the capability message, each SRS resource in the set of multiple SRS resources being associated with a corresponding resource set in the set of multiple resource sets, wherein the mapping indicates a mapping between each SRS resource in the set of multiple SRS resources and a corresponding bit sequence in the set of multiple bit sequences.

[0200] In some examples, to support sending the SRS configuration, mapping component 1730 can be configured as or otherwise support components for sending an SRS configuration indicating a virtual resource set comprising a subset of the set of multiple SRS resources, wherein the virtual resource set comprises a first SRS resource from the first resource set and a second SRS resource from the second resource set.

[0201] In some examples, to support sending the SRS configuration, mapping component 1730 can be configured as or otherwise support components for sending an SRS configuration indicating a virtual resource set comprising a subset of the set of multiple SRS resources, wherein based on a time slot index corresponding to the control message, the first SRS resource is included in the subset of the set of multiple SRS resources.

[0202] In some examples, to support sending the control message, identifier component 1745 can be configured as or otherwise support means for sending a control message indicating a resource set identifier of a first resource set corresponding to the set of multiple SRS resources.

[0203] In some examples, the first bit sequence includes a single bit.In some examples, the first number of one or more transmit antennas and the third number of one or more ports are the same.

[0204] Figure 18 A diagram of a system 1800 including a device 1805 supporting techniques for mapping SRS resources in accordance with aspects of the present disclosure is shown. Device 1805 may be an example of or include components of device 1505, device 1605, or base station 105 as described herein. Device 1805 may wirelessly communicate with one or more base stations 105, UEs 115, or any combination thereof. Device 1805 may include components for two-way voice and data communications, including components for sending and receiving communications, such as a communications manager 1820, a network communications manager 1810, a transceiver 1815, an antenna 1825, memory 1830, code 1835, a processor 1840, and an inter-station communications manager 1845. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1850).

[0205] The network communications manager 1810 may manage communications (eg, via one or more wired backhaul links) with the core network 130. For example, the network communications manager 1810 may manage the routing of data communications for client devices, such as one or more UEs 115.

[0206] In some cases, the device 1805 may include a single antenna 1825. However, in some other cases, the device 1805 may have more than one antenna 1825, which may be capable of transmitting or receiving multiple wireless transmissions simultaneously. As described herein, the transceiver 1815 can communicate bidirectionally via one or more antennas 1825, a wired or wireless link. For example, the transceiver 1815 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. The transceiver 1815 can also include a modem to modulate packets, provide the modulated packets to one or more antennas 1825 for transmission, and demodulate packets received from the one or more antennas 1825. The transceiver 1815 or the transceiver 1815 and one or more antennas 1825 can be examples of the transmitter 1515, the transmitter 1615, the receiver 1510, the receiver 1610, or any combination thereof, or components thereof, as described herein.

[0207] The memory 1830 may include RAM and ROM. The memory 1830 may store computer-readable, computer-executable code 1835 including instructions that, when executed by the processor 1840, cause the device 1805 to perform the various functions described herein. The code 1835 may be stored in a non-transitory computer-readable medium (such as system memory or another type of memory). In some cases, the code 1835 may not be directly executable by the processor 1840, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein. In some cases, the memory 1830 may include, among other things, a BIOS that may control basic hardware or software operations, such as interacting with peripheral components or devices.

[0208] The processor 1840 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 1840 may be configured to operate the memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1840. The processor 1840 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1830) to cause the device 1805 to perform various functions (e.g., functions or tasks supporting a technique for mapping SRS resources). For example, the device 1805 or a component of the device 1805 may include a processor 1840 and a memory 1830 coupled to the processor 1840, the processor 1840 and the memory 1830 being configured to perform the various functions described herein.

[0209] The inter-site communication manager 1845 can manage communications with other base stations 105 and can include a controller or scheduler for coordinating with other base stations 105 to control communications with UE 115. For example, the inter-site communication manager 1845 can coordinate the scheduling of transmissions to UE 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-site communication manager 1845 can provide an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between base stations 105.

[0210] The communication manager 1820 may support wireless communications at a base station according to examples disclosed herein. For example, the communication manager 1820 may be configured to or otherwise support components for receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. The communication manager 1820 may be configured to or otherwise support components for sending an SRS configuration to the UE based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. The communication manager 1820 may be configured to or otherwise support components for sending a control message including a first bit sequence in the set of multiple bit sequences, the control message indicating a first SRS resource in the subset of the set of multiple SRS resources based on the mapping. The communication manager 1820 may be configured or otherwise support means for receiving a first SRS in a first SRS resource based on the control message.

[0211] By including or configuring a communication manager 1820 according to the examples described herein, the device 1805 can support techniques for reducing delays associated with SRI transmissions and more efficiently utilizing communication resources (e.g., SRS resources) based on combining SRS resources used for codebook-based SRS transmissions with SRS transmissions used for antenna switching procedures.

[0212] In some examples, the communication manager 1820 can be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with the transceiver 1815, one or more antennas 1825, or any combination thereof. Although the communication manager 1820 is shown as a separate component, in some examples, one or more functions described with reference to the communication manager 1820 can be supported or performed by the processor 1840, the memory 1830, the code 1835, or any combination thereof. For example, the code 1835 can include instructions executable by the processor 1840 to cause the device 1805 to perform various aspects of the techniques for mapping SRS resources as described herein, or the processor 1840 and the memory 1830 can be otherwise configured to perform or support such operations.

[0213] Figure 19 A flow chart illustrating a method 1900 for mapping SRS resources according to aspects of the present disclosure is shown. The operations of the method 1900 may be implemented by a UE or components thereof as described herein. For example, the operations of the method 1900 may be implemented by a UE or components thereof as described herein. Figures 1 to 14 The described functions may be performed by the UE 115. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0214] At 1905, the method may include sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. Operation 1905 may be performed according to examples disclosed herein. In some examples, aspects of operation 1905 may be performed as described in reference to Figure 13 The described capability component 1325 is executed.

[0215] At 1910, the method may include receiving an SRS configuration for a set of multiple SRS resources based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. Operation 1910 may be performed according to examples disclosed herein. In some examples, aspects of operation 1910 may be performed as described in reference to Figure 13 The described mapping component 1330 is performed.

[0216] At 1915, the method may include receiving a control message including a first bit sequence in the set of the plurality of bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of the plurality of SRS resources based on the mapping. Operation 1915 may be performed according to examples disclosed herein. In some examples, aspects of operation 1915 may be performed as described in reference to Figure 13 The described bit sequence component 1335 is executed.

[0217] At 1920, the method may include sending a first SRS in the first SRS resource based on the control message. Operation 1920 may be performed according to examples disclosed herein. In some examples, aspects of operation 1920 may be performed as described in reference to Figure 13 The described SRS component 1340 is executed.

[0218] Figure 20 A flow chart illustrating a method 2000 for mapping SRS resources according to aspects of the present disclosure is shown. The operations of the method 2000 may be implemented by a UE or components thereof as described herein. For example, the operations of the method 2000 may be implemented by a UE or components thereof as described herein. Figures 1 to 14 The described functions may be performed by the UE 115. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0219] At 2005, the method may include sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. Operation 2005 may be performed according to examples disclosed herein. In some examples, aspects of operation 2005 may be performed as described in reference to Figure 13 The described capability component 1325 is executed.

[0220] At 2010, the method may include receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. Operation 2010 may be performed according to examples disclosed herein. In some examples, aspects of operation 2010 may be performed as described in reference to Figure 13 The described mapping component 1330 is performed.

[0221] At 2015, the method may include receiving a control message including a first bit sequence in the set of the plurality of bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of the plurality of SRS resources based on the mapping. Operation 2015 may be performed according to examples disclosed herein. In some examples, aspects of operation 2015 may be performed as described in reference to Figure 13 The described bit sequence component 1335 is executed.

[0222] At 2020, the method may include receiving an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers. Operation 2020 may be performed according to examples disclosed herein. In some examples, aspects of operation 2020 may be performed as described in reference to Figure 13 The described identifier component 1345 is executed.

[0223] At 2025, the method may include sending a first SRS in the first SRS resource based on the control message. Operation 2025 may be performed according to examples disclosed herein. In some examples, aspects of operation 2025 may be performed as described in reference to Figure 13 The described SRS component 1340 is executed.

[0224] Figure 21 A flow chart illustrating a method 2100 for mapping SRS resources according to aspects of the present disclosure is shown. The operations of the method 2100 may be implemented by a UE or components thereof as described herein. For example, the operations of the method 2100 may be implemented by a UE or components thereof as described herein. Figures 1 to 14 The described functions may be performed by the UE 115. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0225] At 2105, the method may include sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. Operation 2105 may be performed according to examples disclosed herein. In some examples, aspects of operation 2105 may be performed as described in reference to Figure 13 The described capability component 1325 is executed.

[0226] At 2110, the method may include receiving an SRS configuration based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. Operation 2110 may be performed according to examples disclosed herein. In some examples, aspects of operation 2110 may be performed as described in reference to Figure 13 The described mapping component 1330 is performed.

[0227] At 2115, the method may include receiving an SRS configuration indicating a set of multiple resource sets. Operation 2115 may be performed according to examples disclosed herein. In some examples, aspects of operation 2115 may be performed as described in reference to Figure 13 The indicator component 1350 is described to perform.

[0228] At 2120, the method may include receiving a control message including a first bit sequence in the set of the plurality of bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of the plurality of SRS resources based on the mapping, and the control message indicating a first resource set in the set of the plurality of resource sets associated with the subset of the set of the plurality of SRS resources and indicating the first SRS resource in the subset of the set of the plurality of SRS resources. Operation 2120 may be performed according to examples disclosed herein. In some examples, aspects of operation 2120 may be performed as described with reference to Figure 13 The described bit sequence component 1335 is executed.

[0229] At 2125, the method may include sending a first SRS in the first SRS resource based on the control message. Operation 2125 may be performed according to examples disclosed herein. In some examples, aspects of operation 2125 may be performed as described in reference to Figure 13 The described SRS component 1340 is executed.

[0230] Figure 22 A flow chart illustrating a method 2200 for mapping SRS resources according to aspects of the present disclosure is shown. The operations of the method 2200 may be implemented by a base station or components thereof as described herein. For example, the operations of the method 2200 may be implemented by a base station or components thereof as described herein. Figures 1 to 10 and Figures 15 to 18 The base station 105 described herein may be executed. In some examples, the base station may execute an instruction set to control functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the described functions.

[0231] At 2205, the method may include receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. Operation 2205 may be performed according to examples disclosed herein. In some examples, aspects of operation 2205 may be performed as described in reference to Figure 17 The described capability component 1725 is executed.

[0232] At 2210, the method may include sending an SRS configuration for a set of multiple SRS resources to the UE based on the capability message, the SRS configuration indicating a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. Operation 2210 may be performed according to examples disclosed herein. In some examples, aspects of operation 2210 may be performed as described in reference to Figure 17 The described mapping component 1730 is performed.

[0233] At 2215, the method may include sending a control message including a first bit sequence in the set of the plurality of bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of the plurality of SRS resources based on the mapping. Operation 2215 may be performed according to examples disclosed herein. In some examples, aspects of operation 2215 may be performed as described in reference to Figure 17 The described bit sequence component 1735 is executed.

[0234] At 2220, the method may include receiving a first SRS in the first SRS resource based on the control message. Operation 2220 may be performed according to examples disclosed herein. In some examples, aspects of operation 2220 may be performed as described in reference to Figure 17 The described SRS component 1740 is executed.

[0235] Figure 23 A flow chart illustrating a method 2300 for mapping SRS resources according to aspects of the present disclosure is shown. The operations of the method 2300 may be implemented by a base station or components thereof as described herein. For example, the operations of the method 2300 may be implemented by a base station or components thereof as described herein. Figures 1 to 10 and Figures 15 to 18 The base station 105 described herein may be executed. In some examples, the base station may execute an instruction set to control functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the described functions.

[0236] At 2305, the method may include receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission. Operation 2305 may be performed according to examples disclosed herein. In some examples, aspects of operation 2305 may be performed as described in reference to Figure 17 The described capability component 1725 is executed.

[0237] At 2310, the method may include sending an SRS configuration to the UE based on the capability message, the SRS configuration indicating a set of multiple SRS resources and a mapping between each SRS resource in at least a subset of the set of multiple SRS resources and a corresponding bit sequence in a set of multiple bit sequences. Operation 2310 may be performed according to examples disclosed herein. In some examples, aspects of operation 2310 may be performed as described in reference to Figure 17 The described mapping component 1730 is performed.

[0238] At 2315, the method may include sending a control message including a first bit sequence in the set of the plurality of bit sequences, the control message being used to indicate a first SRS resource in the subset of the set of the plurality of SRS resources based on the mapping. Operation 2315 may be performed according to examples disclosed herein. In some examples, aspects of operation 2315 may be performed as described in reference to Figure 17 The described bit sequence component 1735 is executed.

[0239] At 2320, the method may include sending an indication of a set of multiple identifiers corresponding to a set of multiple resource sets, wherein a subset of the set of multiple SRS resources corresponds to a first resource set in the set of multiple resource sets associated with a first identifier in the set of multiple identifiers. Operation 2320 may be performed according to examples disclosed herein. In some examples, aspects of operation 2320 may be performed as described with reference to Figure 17 The described identifier component 1745 is executed.

[0240] At 2325, the method may include receiving a first SRS in the first SRS resource based on the control message. Operation 2325 may be performed according to examples disclosed herein. In some examples, aspects of operation 2325 may be performed as described in reference to Figure 17 The described SRS component 1740 is executed.

[0241] Overview of various aspects

[0242] The following provides an overview of various aspects of the disclosure:

[0243] Aspect 1: A method for wireless communication at a UE, comprising: sending a capability message, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; receiving a sounding reference signal configuration for multiple sounding reference signal resources based at least in part on the capability message, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the multiple sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; receiving a control message including a first bit sequence in the multiple bit sequences, the control message being used to indicate a first sounding reference signal resource in the subset of the multiple sounding reference signal resources based at least in part on the mapping; and sending a first sounding reference signal in the first sounding reference signal resource based at least in part on the control message.

[0244] Aspect 2: A method according to aspect 1, wherein receiving the control message includes: receiving an indication of multiple identifiers corresponding to multiple resource sets, wherein a subset of the multiple sounding reference signal resources corresponds to a first resource set in the multiple resource sets associated with a first identifier in the multiple identifiers.

[0245] Aspect 3: The method according to aspect 2, wherein the first identifier is the highest or lowest identifier among a plurality of identifiers corresponding to the plurality of resource sets.

[0246] Aspect 4: A method according to any one of Aspects 1 to 3, wherein receiving the sounding reference signal configuration includes: receiving a sounding reference signal configuration indicating multiple resource sets, wherein the control message indicates a first resource set in the multiple resource sets associated with a subset of the multiple sounding reference signal resources and indicates a first sounding reference signal resource in the subset of the multiple sounding reference signal resources.

[0247] Aspect 5: The method according to aspect 4, wherein receiving the control message comprises: receiving a control message including a set indicator having a zero value, the set indicator indicating a first resource set among the plurality of resource sets.

[0248] Aspect 6: The method according to any one of aspects 4 to 5, wherein receiving the control message comprises: receiving a control message including a set indicator having a non-zero value, the set indicator indicating the first resource set of the multiple resource sets.

[0249] Aspect 7: The method according to aspect 6, wherein receiving the control message comprises: receiving a control message including a resource indicator having a value of zero, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

[0250] Aspect 8: The method according to aspect 6, wherein receiving the control message includes: receiving a control message including a resource indicator with a non-zero value, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

[0251] Aspect 9: A method according to any one of Aspects 1 to 8, wherein receiving the sounding reference signal configuration further comprises: receiving a sounding reference signal configuration indicating a single resource set associated with the multiple sounding reference signal resources based at least in part on the capability message, wherein the mapping indicates a mapping between each of the multiple sounding reference signal resources and a corresponding bit sequence in the multiple bit sequences.

[0252] Aspect 10: A method according to any one of Aspects 1 to 8, further comprising: receiving a sounding reference signal configuration indicating multiple resource sets based at least in part on the capability message, each of the multiple sounding reference signal resources being associated with a corresponding resource set in the multiple resource sets, wherein the mapping indicates a mapping between each of the multiple sounding reference signal resources and a corresponding bit sequence in the multiple bit sequences.

[0253] Aspect 11: A method according to any one of Aspects 1 to 10, wherein receiving the sounding reference signal configuration further comprises: receiving a sounding reference signal configuration indicating a virtual resource set including a subset of the multiple sounding reference signal resources, wherein the virtual resource set includes a first sounding reference signal resource from a first resource set and a second sounding reference signal resource from a second resource set.

[0254] Aspect 12: A method according to any one of Aspects 1 to 10, wherein receiving the sounding reference signal configuration further comprises: receiving a sounding reference signal configuration indicating a virtual resource set including a subset of the multiple sounding reference signal resources, wherein the first sounding reference signal resource is included in the subset of the multiple sounding reference signal resources based at least in part on a time slot index corresponding to the control message.

[0255] Aspect 13: The method according to any one of aspects 1 to 12, wherein receiving the control message comprises: receiving a control message indicating a resource set identifier of a first resource set corresponding to the plurality of sounding reference signal resources.

[0256] Aspect 14: The method according to any one of aspects 1 to 13, wherein the first bit sequence comprises a single bit.

[0257] Aspect 15: The method according to any one of aspects 1 to 14, wherein the first number of the one or more transmit antennas and the third number of the one or more ports are the same.

[0258] Aspect 16: A method for wireless communication at a base station, comprising: receiving a capability message from a UE, the capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; sending a sounding reference signal configuration for a plurality of sounding reference signal resources to the UE and based at least in part on the capability message, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the plurality of sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; sending a control message including a first bit sequence in the plurality of bit sequences, the control message being used to indicate a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; and receiving a first sounding reference signal in the first sounding reference signal resource based at least in part on the control message.

[0259] Aspect 17: A method according to Aspect 16, wherein sending the control message includes: sending an indication of multiple identifiers corresponding to multiple resource sets, wherein a subset of the multiple sounding reference signal resources corresponds to a first resource set in the multiple resource sets associated with a first identifier in the multiple identifiers.

[0260] Aspect 18: The method according to aspect 17, wherein the first identifier is a highest or lowest identifier among a plurality of identifiers corresponding to the plurality of resource sets.

[0261] Aspect 19: A method according to any one of Aspects 16 to 18, wherein sending the sounding reference signal configuration includes: sending a sounding reference signal configuration indicating multiple resource sets, wherein the control message indicates a first resource set in the multiple resource sets associated with a subset of the multiple sounding reference signal resources and indicates a first sounding reference signal resource in the subset of the multiple sounding reference signal resources.

[0262] Aspect 20: The method according to aspect 19, wherein sending the control message comprises sending a control message including a set indicator having a value of zero, the set indicator indicating a first resource set among the plurality of resource sets.

[0263] Aspect 21: The method according to any one of Aspect 19, wherein sending the control message comprises sending a control message including a set indicator having a non-zero value, the set indicator indicating a first resource set among the plurality of resource sets.

[0264] Aspect 22: The method according to any one of aspects 19 to 21, wherein sending the control message comprises sending a control message including a resource indicator having a zero value, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

[0265] Aspect 23: A method according to any one of aspects 19 to 21, wherein sending the control message comprises: sending a control message including a resource indicator with a non-zero value, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

[0266] Aspect 24: A method according to any one of Aspects 16 to 23, wherein sending the sounding reference signal configuration further comprises: sending a sounding reference signal configuration indicating a single resource set associated with the multiple sounding reference signal resources based at least in part on the capability message, wherein the mapping indicates a mapping between each of the multiple sounding reference signal resources and a corresponding bit sequence in the multiple bit sequences.

[0267] Aspect 25: A method according to any one of Aspects 16 to 23, further comprising: sending a sounding reference signal configuration indicating multiple resource sets based at least in part on the capability message, each of the multiple sounding reference signal resources being associated with a corresponding resource set in the multiple resource sets, wherein the mapping indicates a mapping between each of the multiple sounding reference signal resources and a corresponding bit sequence in the multiple bit sequences.

[0268] Aspect 26: A method according to any one of Aspects 16 to 25, wherein sending the sounding reference signal configuration further comprises: sending a sounding reference signal configuration indicating a virtual resource set including a subset of the multiple sounding reference signal resources, wherein the virtual resource set includes a first sounding reference signal resource from a first resource set and a second sounding reference signal resource from a second resource set.

[0269] Aspect 27: A method according to any one of Aspects 16 to 25, wherein sending the sounding reference signal configuration further comprises: sending a sounding reference signal configuration indicating a virtual resource set including a subset of the multiple sounding reference signal resources, wherein the first sounding reference signal resource is included in the subset of the multiple sounding reference signal resources based at least in part on a time slot index corresponding to the control message.

[0270] Aspect 28: The method according to any one of aspects 16 to 27, wherein sending the control message comprises sending a control message indicating a resource set identifier of a first resource set corresponding to the plurality of sounding reference signal resources.

[0271] Aspect 29: The method of any one of aspects 16 to 28, wherein the first sequence comprises a single bit.

[0272] Aspect 30: The method according to any one of aspects 16 to 29, wherein the first number of the one or more transmit antennas and the third number of the one or more ports are the same.

[0273] Aspect 31: An apparatus for wireless communication at a UE, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to any one of aspects 1 to 15.

[0274] Aspect 32: An apparatus for wireless communication at a UE, comprising at least one component for performing the method according to any one of aspects 1 to 15.

[0275] Aspect 33: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method according to any one of aspects 1 to 15.

[0276] Aspect 34: An apparatus for performing wireless communication at a base station, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory, and the instructions are executable by the processor to cause the apparatus to perform the method of any one of aspects 16 to 30.

[0277] Aspect 35: An apparatus for wireless communication at a base station, comprising at least one means for performing the method of any one of aspects 16 to 30.

[0278] Aspect 36: A non-transitory computer-readable medium storing code for wireless communication at a base station, the code comprising instructions executable by a processor to perform the method of any one of aspects 16 to 30.

[0279] It should be noted that the methods described herein describe possible implementations, and that the operations and steps may be rearranged or otherwise modified, and that other implementations are possible. Furthermore, aspects from two or more of these methods may be combined.

[0280] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and the terminology of LTE, LTE-A, LTE-A Pro, or NR may be used in many descriptions, the techniques described herein are also applicable beyond LTE, LTE-A, LTE-A Pro, or NR systems. For example, the described techniques are applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0281] The information and signals described herein may be represented using any of a variety of technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be mentioned throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0282] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed using a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration).

[0283] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted via a computer-readable medium as one or more instructions or codes. Other examples and implementations are within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hard wiring, or any combination thereof. Features that implement the functions may also be physically located at various locations, including portions that are distributed so as to implement the functions at different physical locations.

[0284] Computer-readable media include both non-transitory computer storage media and communication media, and communication media include any media that helps to transfer a computer program from one place to another.Non-transitory storage media can be any available media that can be accessed by a general or special-purpose computer.As an example and not limitation, non-transitory computer-readable media can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or can be used to carry or store required program code in the form of instructions or data structures and any other non-transitory media that can be accessed by a general or special-purpose computer or a general or special-purpose processor. In addition, any connection is appropriately referred to as computer-readable media. For example, if software is sent from a website, server or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwaves, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, radio and microwaves are included in the definition of computer-readable media. Disk and disc, as used herein, include CDs, laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0285] As used herein, including in the claims, "or" used in a list of items (e.g., a list of items preceded by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C refers to A or B or C or AB or AC or BC or ABC (i.e., A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an example step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of this disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on."

[0286] In the drawings, similar components or features may have the same reference number. In addition, various components of the same type may be distinguished by following the reference number with a dash and a second reference number that distinguishes between similar components. If only the first reference number is used in the specification, the description applies to any one of the similar components having the same first reference number, regardless of the second or subsequent reference numbers.

[0287] The description set forth herein in conjunction with the accompanying drawings describes example configurations and does not represent all examples that can be implemented or within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration," rather than "preferred" or "superior to other examples." To provide an understanding of the described techniques, the detailed description includes specific details. However, these techniques can be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0288] The description herein is provided to enable one of ordinary skill in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication by a user equipment (UE), comprising: transmitting a capabilities message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; receiving a sounding reference signal configuration for a plurality of sounding reference signal resources based at least in part on the capability message, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the plurality of sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; receiving a control message including a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as A first sounding reference signal is sent in the first sounding reference signal resource based at least in part on the control message.

2. The method of claim 1 , wherein receiving the control message comprises: An indication of a plurality of identifiers corresponding to a plurality of resource sets is received, wherein a subset of the plurality of sounding reference signal resources corresponds to a first resource set of the plurality of resource sets associated with a first identifier of the plurality of identifiers. 3 . The method of claim 2 , wherein the first identifier is a highest or lowest identifier among the plurality of identifiers corresponding to the plurality of resource sets.

4. The method of claim 1 , wherein receiving the sounding reference signal configuration comprises: A sounding reference signal configuration is received indicating a plurality of resource sets, wherein the control message indicates a first resource set of the plurality of resource sets associated with a subset of the plurality of sounding reference signal resources and indicates a first sounding reference signal resource of the subset of the plurality of sounding reference signal resources.

5. The method of claim 4, wherein receiving the control message comprises: A control message is received including a set indicator having a value of zero, the set indicator indicating the first set of resources among the plurality of sets of resources.

6. The method of claim 4, wherein receiving the control message comprises: A control message is received including a set indicator having a non-zero value, the set indicator indicating the first set of resources among the plurality of sets of resources.

7. The method of claim 4, wherein receiving the control message comprises: A control message including a resource indicator having a value of zero is received, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

8. The method of claim 4, wherein receiving the control message comprises: A control message is received including a resource indicator having a non-zero value, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

9. The method of claim 1 , wherein receiving the sounding reference signal configuration further comprises: A sounding reference signal configuration is received based at least in part on the capability message indicating a single resource set associated with the plurality of sounding reference signal resources, wherein the mapping indicates a mapping between each of the plurality of sounding reference signal resources and a corresponding bit sequence of the plurality of bit sequences.

10. The method according to claim 1, further comprising: and receiving a sounding reference signal configuration indicating a plurality of resource sets based at least in part on the capability message, each of the plurality of sounding reference signal resources being associated with a respective resource set of the plurality of resource sets, wherein the mapping indicates a mapping between each of the plurality of sounding reference signal resources and a respective bit sequence of the plurality of bit sequences.

11. The method of claim 1 , wherein receiving the sounding reference signal configuration further comprises: A sounding reference signal configuration is received that indicates a virtual resource set comprising a subset of the plurality of sounding reference signal resources, wherein the virtual resource set comprises a first sounding reference signal resource from a first resource set and a second sounding reference signal resource from a second resource set.

12. The method of claim 1 , wherein receiving the sounding reference signal configuration further comprises: A sounding reference signal configuration is received that indicates a virtual resource set including a subset of the plurality of sounding reference signal resources, wherein the first sounding reference signal resource is included in the subset of the plurality of sounding reference signal resources based at least in part on a slot index corresponding to the control message.

13. The method of claim 1 , wherein receiving the control message comprises: A control message indicating a resource set identifier of a first resource set corresponding to the plurality of sounding reference signal resources is received. The method of claim 1 , wherein the first sequence comprises a single bit.

15. The method of claim 1, wherein the first number of the one or more transmit antennas and the third number of the one or more ports are the same.

16. A method for wireless communication by a network node, comprising: receiving a capabilities message from a user equipment (UE), the capabilities message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; transmitting, to the UE and based at least in part on the capability message, a sounding reference signal configuration for a plurality of sounding reference signal resources, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the plurality of sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; transmitting a control message including a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as A first sounding reference signal is received in the first sounding reference signal resource based at least in part on the control message.

17. The method of claim 16, wherein sending the control message comprises: An indication of a plurality of identifiers corresponding to a plurality of resource sets is sent, wherein a subset of the plurality of sounding reference signal resources corresponds to a first resource set of the plurality of resource sets associated with a first identifier of the plurality of identifiers.

18. The method of claim 17, wherein the first identifier is a highest or lowest identifier among the plurality of identifiers corresponding to the plurality of resource sets.

19. The method of claim 16, wherein sending the sounding reference signal configuration comprises: A sounding reference signal configuration is sent indicating a plurality of resource sets, wherein the control message indicates a first resource set of the plurality of resource sets associated with a subset of the plurality of sounding reference signal resources and indicates a first sounding reference signal resource of the subset of the plurality of sounding reference signal resources.

20. The method of claim 19, wherein sending the control message comprises: A control message is sent including a set indicator having a value of zero, the set indicator indicating the first set of resources among the plurality of sets of resources.

21. The method of claim 19, wherein sending the control message comprises: A control message is sent including a set indicator having a non-zero value, the set indicator indicating the first set of resources among the plurality of sets of resources.

22. The method of claim 19, wherein sending the control message comprises: A control message is sent including a resource indicator having a value of zero, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

23. The method of claim 19, wherein sending the control message comprises: A control message is sent including a resource indicator having a non-zero value, the resource indicator indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources.

24. The method of claim 16, wherein sending the sounding reference signal configuration further comprises: A sounding reference signal configuration is sent based at least in part on the capability message indicating a single resource set associated with the plurality of sounding reference signal resources, wherein the mapping indicates a mapping between each of the plurality of sounding reference signal resources and a corresponding bit sequence of the plurality of bit sequences.

25. The method of claim 16, further comprising: and sending a sounding reference signal configuration indicating a plurality of resource sets based at least in part on the capability message, each of the plurality of sounding reference signal resources being associated with a respective resource set of the plurality of resource sets, wherein the mapping indicates a mapping between each of the plurality of sounding reference signal resources and a respective bit sequence of the plurality of bit sequences.

26. The method of claim 16, wherein sending the sounding reference signal configuration further comprises: A sounding reference signal configuration is transmitted indicating a virtual resource set comprising a subset of the plurality of sounding reference signal resources, wherein the virtual resource set comprises a first sounding reference signal resource from a first resource set and a second sounding reference signal resource from a second resource set.

27. The method of claim 16, wherein sending the sounding reference signal configuration further comprises: and transmitting a sounding reference signal configuration indicating a virtual resource set comprising a subset of the plurality of sounding reference signal resources, wherein the first sounding reference signal resource is included in the subset of the plurality of sounding reference signal resources based at least in part on a slot index corresponding to the control message.

28. The method of claim 16, wherein sending the control message comprises: A control message indicating a resource set identifier of a first resource set corresponding to the plurality of sounding reference signal resources is transmitted.

29. The method of claim 16, wherein the first sequence comprises a single bit.

30. The method of claim 16, wherein the first number of the one or more transmit antennas and the third number of the one or more ports are the same.

31. An apparatus for wireless communication by a user equipment (UE), comprising: processor; a memory coupled to the processor; as well as instructions stored in the memory and executable by the processor to cause the apparatus to: transmitting a capabilities message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; receiving a sounding reference signal configuration for a plurality of sounding reference signal resources based at least in part on the capability message, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the plurality of sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; receiving a control message including a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as A first sounding reference signal is sent in the first sounding reference signal resource based at least in part on the control message.

32. The apparatus of claim 31 , wherein the instructions for receiving the control message are executable by the processor to cause the apparatus to: An indication of a plurality of identifiers corresponding to a plurality of resource sets is received, wherein a subset of the plurality of sounding reference signal resources corresponds to a first resource set of the plurality of resource sets associated with a first identifier of the plurality of identifiers.

33. The apparatus of claim 31 , wherein the instructions for receiving the sounding reference signal configuration are executable by the processor to cause the apparatus to: A sounding reference signal configuration is received indicating a plurality of resource sets, wherein the control message indicates a first resource set of the plurality of resource sets associated with a subset of the plurality of sounding reference signal resources and indicates a first sounding reference signal resource of the subset of the plurality of sounding reference signal resources.

34. An apparatus for wireless communication by a network node, comprising: processor; a memory coupled to the processor; as well as instructions stored in the memory and executable by the processor to cause the apparatus to: receiving a capabilities message from a user equipment (UE), the capabilities message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; transmitting, to the UE and based at least in part on the capability message, a sounding reference signal configuration for a plurality of sounding reference signal resources, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource in at least a subset of the plurality of sounding reference signal resources and a corresponding bit sequence in a plurality of bit sequences; transmitting a control message including a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as A first sounding reference signal is received in the first sounding reference signal resource based at least in part on the control message.

35. An apparatus for wireless communication by a user equipment (UE), comprising: means for sending a capability message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; means for receiving a sounding reference signal configuration for a plurality of sounding reference signal resources based at least in part on the capability message, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource of at least a subset of the plurality of sounding reference signal resources and a respective bit sequence of a plurality of bit sequences; means for receiving a control message comprising a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as Means for sending a first sounding reference signal in the first sounding reference signal resource based at least in part on the control message.

36. An apparatus for wireless communication by a network node, comprising: means for receiving a capabilities message from a user equipment (UE), the capabilities message indicating a first number of one or more transmit antennas supported by the UE for antenna switching, a second number of receive antennas supported by the UE for antenna switching that exceeds the first number of the one or more transmit antennas, and a third number of one or more ports supported for uplink transmission; means for sending, to the UE and based at least in part on the capability message, a sounding reference signal configuration for a plurality of sounding reference signal resources, the sounding reference signal configuration indicating a mapping between each sounding reference signal resource of at least a subset of the plurality of sounding reference signal resources and a respective bit sequence of a plurality of bit sequences; means for transmitting a control message comprising a first bit sequence of the plurality of bit sequences, the control message indicating a first sounding reference signal resource in the subset of the plurality of sounding reference signal resources based at least in part on the mapping; as well as Means for receiving a first sounding reference signal in the first sounding reference signal resource based at least in part on the control message.

37. A computer-readable medium having one or more computer instructions recorded thereon, which, when executed by one or more processors of a user equipment (UE), cause the one or more processors to perform the method for wireless communication according to any one of claims 1-15.

38. A computer-readable medium having one or more computer instructions recorded thereon, which, when executed by one or more processors of a network node, cause the one or more processors to perform the wireless communication method according to any one of claims 16 to 30.

39. A computer program product comprising one or more computer instructions which, when executed by one or more processors of a user equipment (UE), cause the one or more processors to perform the method of wireless communication according to any one of claims 1-15.

40. A computer program product comprising one or more computer instructions which, when executed by one or more processors of a network node, cause the one or more processors to perform the method of wireless communication according to any one of claims 16-30.

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