Beam switching technology for uplink transmission

Abstract

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive sounding reference signal (SRS) resource set configuration information indicating an aperiodic SRS resource set, an aperiodic downlink reference signal resource associated with the aperiodic SRS resource set, and a time slot offset associated with the aperiodic downlink reference signal resource. The UE may receive downlink control information indicating that the aperiodic SRS resource set is triggered and determine a quasi-co-location assumption for the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource. The UE may measure the aperiodic downlink reference signal resource in a time slot indicated by the time slot offset based on the quasi-co-location assumption.

Description

Technical Field

[0001] The following relates generally to wireless communications, and more particularly to beam switching techniques for uplink transmissions. 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 may be able to 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 frequency division multiple access (OFDMA), or discrete Fourier transform extended 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, which may support communication of multiple communication devices simultaneously, respectively, and these communication devices may be referred to as user equipment (UE) in addition.

[0003] In some wireless systems, devices may communicate using beamforming. For example, a UE may select a beam to monitor downlink resources and transmit on uplink resources. Some techniques for applying beamforming configurations may be improved. Summary of the invention

[0004] The described technology relates to improved methods, systems, devices and apparatuses for supporting beam switching techniques for uplink transmissions. In general, the described technology provides quasi-co-location (QCL) for determining downlink reference signal resources, which is used to determine an uplink pre-decoder for non-codebook-based uplink transmissions. For non-codebook-based uplink transmissions, a user equipment (UE) can determine an uplink pre-decoder for transmission on a sounding reference signal (SRS) resource set based on measurements of downlink reference signal resources such as channel state information reference signal (CSI-RS) resources. The base station can configure an SRS resource set and indicate the associated downlink reference signal resources. In some cases, the SRS resource set and the downlink reference signal resource can be non-periodic and triggered by downlink control information (DCI). When the UE receives a triggering DCI, the UE can measure the downlink reference signal resources, determine the transmission pre-decoder based on the measurement, and use the pre-decoder to send the SRS on the indicated SRS resources.

[0005] According to the technology described in this article, the base station can configure the UE with a downlink reference signal resource slot offset. The downlink reference signal resource can be included in a time slot as indicated by the downlink reference signal resource slot offset. The time slot offset of the downlink reference resource can provide the UE with enough time to determine the QCL assumption and switch beam of the downlink reference signal resource to measure the downlink reference signal resource. In some cases, the QCL assumption can be based on the beam switching capability of the UE. For example, if the UE has enough time to determine the QCL assumption and switch beam, the UE can apply the transmission configuration indicator (TCI) state associated with the non-periodic downlink reference signal resource. Otherwise, the UE can use a QCL assumption shared by another signal or a default QCL assumption. The technology in this article also uses a media access control (MAC) control element (CE) to describe a more dynamic configuration and reconfiguration of the downlink reference signal resource associated with the SRS resource set. For example, the association between the downlink reference signal resource and the SRS resource set can be configured by RRC signaling. By using MAC CE to update the association between the SRS resource set and the downlink reference signal resources, the UE can have increased flexibility for adjusting the uplink beam. In some cases, the MAC CE can be used to indicate the TCI state of the downlink reference signal resources, which can also be used to adjust the UE's uplink beam without configuring new downlink reference signal resources.

[0006] A method for wireless communication at a UE is described. The method may include: receiving sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; receiving downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determining a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and measuring the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the quasi-co-location assumption.

[0007] A device for wireless communication at a UE is described. The device may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the device to perform the following operations: receive sounding reference signal resource set configuration information, the sounding reference signal resource set configuration information indicating a non-periodic sounding reference signal resource set, a non-periodic downlink reference signal resource associated with the non-periodic sounding reference signal resource set, and a time slot offset associated with the non-periodic downlink reference signal resource; receive downlink control information in a first time slot, the downlink control information indicating that the non-periodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption of the non-periodic downlink reference signal resource based on the time slot offset associated with the non-periodic downlink reference signal resource; and measure the non-periodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the quasi-co-location assumption.

[0008] Another apparatus for wireless communication at a UE is described. The apparatus may include: a component for receiving a sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; a component for receiving downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; a component for determining a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and a component for measuring the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the quasi-co-location assumption.

[0009] 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 perform the following operations: receive sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; receive downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption for the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and measure the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the quasi-co-location assumption.

[0010] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the beam switching capability of the UE may be greater than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources; and identifying the TCI state of the non-periodic downlink reference signal resources, wherein the quasi-co-location hypothesis may be associated with the TCI state of the non-periodic downlink reference signal resources based on the beam switching capability being greater than the scheduling offset.

[0011] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the beam switching capability of the UE may be less than a scheduling offset between downlink control information and a non-periodic downlink reference signal resource; and detecting a downlink signal scheduled to overlap with the non-periodic downlink reference signal resource, wherein the quasi-co-location hypothesis may be associated with the downlink signal based on the beam switching capability being less than the scheduling offset.

[0012] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the beam switching capability of the UE can be less than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources; and identifying a default quasi-co-location hypothesis, wherein the quasi-co-location hypothesis can be a default quasi-co-location hypothesis based on the beam switching capability being less than the scheduling offset.

[0013] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, a default quasi co-location hypothesis may be associated with a control resource set having a lowest control resource identifier among the control resource sets monitored in a latest time slot.

[0014] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: receiving a configuration of a non-periodic downlink reference signal resource, the configuration including a TCI state associated with the non-periodic downlink reference signal resource.

[0015] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: determining a scheduling offset for a non-periodic downlink reference signal resource based on a time slot offset, wherein the scheduling offset corresponds to the number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the non-periodic downlink reference signal resource.

[0016] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: identifying a set of configured TCI states; determining that all configured TCI states in the set of configured TCI states may not be associated with the spatial quasi-co-location assumption; and determining a time slot offset to be zero, wherein the non-periodic downlink reference signal resource may be located in the first time slot with downlink control information.

[0017] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the downlink control information includes group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

[0018] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, aperiodic downlink reference signal resources may be triggered based on a sounding reference signal request field in downlink control information.

[0019] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, aperiodic sounding reference signal resource set configuration information may be received in a radio resource control configuration.

[0020] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the aperiodic downlink reference signal resources include aperiodic channel state information reference signal resources.

[0021] A method for wireless communication at a base station is described. The method may include: transmitting sounding reference signal resource set configuration information to a UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; sending downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determining a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and sending the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption.

[0022] A device for wireless communication at a base station is described. The device may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the device to perform the following operations: send sounding reference signal resource set configuration information to a UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; send downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and send the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption.

[0023] Another apparatus for wireless communication at a base station is described. The apparatus may include: a component for sending a sounding reference signal resource set configuration information to a UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; a component for sending downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; a component for determining a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and a component for sending the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption.

[0024] 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 perform the following operations: send sounding reference signal resource set configuration information to a UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; send downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and send the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption.

[0025] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the UE's beam switching capability may be greater than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources; and identifying the TCI state of the non-periodic downlink reference signal resources, wherein the quasi-co-location hypothesis may be associated with the TCI state of the non-periodic downlink reference signal resources based on the UE's beam switching capability being greater than the scheduling offset.

[0026] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the UE's beam switching capability may be less than a scheduling offset between downlink control information and a non-periodic downlink reference signal resource; and identifying a downlink signal scheduled to overlap with the non-periodic downlink reference signal resource, wherein the quasi-co-location hypothesis may be associated with the downlink signal based on the UE's beam switching capability being less than the scheduling offset.

[0027] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the quasi-co-location hypothesis may further include operations, features, components, or instructions for the following steps: determining that the beam switching capability of the UE may be less than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources; and identifying a default quasi-co-location hypothesis, wherein the quasi-co-location hypothesis may be a default quasi-co-location hypothesis based on the UE's beam switching capability being less than the scheduling offset.

[0028] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: sending a configuration of a non-periodic downlink reference signal resource, the configuration comprising a TCI state associated with the non-periodic downlink reference signal resource.

[0029] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: determining a scheduling offset for a non-periodic downlink reference signal resource based on a time slot offset, wherein the scheduling offset corresponds to the number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the non-periodic downlink reference signal resource.

[0030] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the downlink control information includes group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

[0031] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: triggering aperiodic downlink reference signal resources based on a sounding reference signal request field in the downlink control information.

[0032] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, aperiodic sounding reference signal resource set configuration information may be sent in a radio resource control configuration.

[0033] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the aperiodic downlink reference signal resources include channel state information reference signal resources.

[0034] A method of wireless communication at a UE is described. The method may include: receiving a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; determining a quasi co-location assumption for the downlink reference signal resources; and measuring the downlink reference signal resources based on the quasi co-location assumption.

[0035] An apparatus for wireless communication at a UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to perform the following operations: receive a MAC CE indicating a downlink reference signal resource associated with a sounding reference signal resource set; determine a quasi-co-location assumption for the downlink reference signal resource; and measure the downlink reference signal resource based on the quasi-co-location assumption.

[0036] Another apparatus for wireless communication at a UE is described. The apparatus may include: a component for receiving a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; a component for determining a quasi co-location assumption for the downlink reference signal resources; and a component for measuring the downlink reference signal resources based on the quasi co-location assumption.

[0037] 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: receive a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; determine a quasi co-location assumption for the downlink reference signal resources; and measure the downlink reference signal resources based on the quasi co-location assumption.

[0038] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the MACCE includes a non-zero power (NZP) CSI-RS identifier for a downlink reference signal resource, a sounding reference signal resource set identifier for a sounding reference signal resource set, a serving cell index, a bandwidth part identifier, or a combination thereof.

[0039] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the MACCE includes an indicator of a non-periodic resource trigger for a sounding reference signal resource set, a list of non-periodic resource triggers for a sounding reference signal resource set, a time slot offset value for a sounding reference signal resource set, a time slot offset for a downlink reference signal resource, or a combination thereof.

[0040] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: applying a command associated with the MAC CE after sending feedback of a downlink shared channel message including the MAC CE.

[0041] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: receiving, by a MAC CE, a TCI status of a downlink reference signal resource, wherein the quasi-co-location assumption may be based on the TCI status of the downlink reference signal resource.

[0042] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the MACCE includes an indicator of a non-periodic resource trigger for a sounding reference signal resource set, a list of non-periodic resource triggers for a sounding reference signal resource set, a time slot offset value for a sounding reference signal resource set, a time slot offset for a downlink reference signal resource, or a combination thereof.

[0043] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the sounding reference signal resource set may be an aperiodic resource set, a periodic resource set, or a semi-persistent resource set.

[0044] A method of wireless communication at a base station is described. The method may include: sending a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; determining a quasi co-location assumption for the downlink reference signal resources; and sending the downlink reference signal resources based on the quasi co-location assumption.

[0045] An apparatus for wireless communication at a base station is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to perform the following operations: send a MAC CE indicating a downlink reference signal resource associated with a sounding reference signal resource set; determine a quasi co-location assumption for the downlink reference signal resource; and send the downlink reference signal resource based on the quasi co-location assumption.

[0046] Another apparatus for wireless communication at a base station is described. The apparatus may include: means for sending a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; means for determining a quasi co-location assumption for the downlink reference signal resources; and means for sending the downlink reference signal resources based on the quasi co-location assumption.

[0047] 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: send a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set; determine a quasi co-location assumption for the downlink reference signal resources; and send the downlink reference signal resources based on the quasi co-location assumption.

[0048] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the MACCE includes a NZP CSI-RS identifier for a downlink reference signal resource, a sounding reference signal resource set identifier for a sounding reference signal resource set, a serving cell index, a bandwidth part identifier, or a combination thereof.

[0049] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the MACCE includes an indicator of a non-periodic resource trigger for a sounding reference signal resource set, a list of non-periodic resource triggers for a sounding reference signal resource set, a time slot offset value for a sounding reference signal resource set, a time slot offset for a downlink reference signal resource, or a combination thereof.

[0050] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for the following steps: indicating, by a MAC CE, a TCI state of a downlink reference signal resource, wherein the quasi-co-location assumption may be based on the TCI state of the downlink reference signal resource.

[0051] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the sounding reference signal resource set may be an aperiodic resource set, a periodic resource set, or a semi-persistent resource set. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 An example of a system for wireless communication supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated.

[0053] Figure 2 An example of a wireless communication system supporting a beam switching technique for uplink transmission according to aspects of the present disclosure is illustrated.

[0054] Figure 3 An example of an aperiodic sounding reference signal (SRS) resource set configuration supporting a beam switching technique for uplink transmission according to aspects of the present disclosure is illustrated.

[0055] Figure 4 An example of a process flow supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated.

[0056] Figure 5 An example of a process flow supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated.

[0057] Figure 6 and Figure 7 A block diagram of a device supporting beam switching techniques for uplink transmission according to aspects of the present disclosure is shown.

[0058] Figure 8 A block diagram of a communication manager supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown.

[0059] Fig. 9 A diagram of a system including devices supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown.

[0060] Fig.10 and Fig.11 A block diagram of a device supporting beam switching techniques for uplink transmission according to aspects of the present disclosure is shown.

[0061] Fig.12A block diagram of a communication manager supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown.

[0062] Fig.13 A diagram of a system including devices supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown.

[0063] Figures 14 to 18 A flow chart illustrating a method of supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0064] A user equipment (UE) may be configured for non-codebook based uplink transmission. For non-codebook based uplink transmission, the UE may determine an uplink predecoder for transmission on a sounding reference signal (SRS) resource set based on measurements of downlink reference signal resources such as channel state information reference signal (CSI-RS) resources. The base station may configure an SRS resource set and indicate associated downlink reference signal resources. In some cases, the SRS resource set and the downlink reference signal resource may be aperiodic and triggered by downlink control information (DCI). When the UE receives a triggering DCI, the UE may measure the downlink reference signal resources, calculate the predecoder based on the downlink reference signal resources and transmit the SRS on the SRS resources indicated by the DCI. The base station receives the pre-decoded SRS resources and indicates one or more of the SRS resources to the UE with an uplink grant. The UE then configures uplink transmission on the granted resources based on the beam and pre-decoding of the indicated SRS resources. In some systems, the aperiodic downlink reference signal resources may be located in the same time slot as the DCI. However, in some cases, the UE may communicate using the spatial quasi-co-location (QCL) assumption. If the aperiodic downlink reference signal resources are located in the same time slot as the DCI, the UE may not have enough time to switch beams to receive the aperiodic downlink reference signal resources.

[0065] The wireless communication system described herein supports techniques for enhanced uplink beam switching. For example, these techniques can be implemented by the UE to determine and apply a QCL assumption to measure aperiodic downlink reference signal resources and determine an uplink pre-decoder of an associated aperiodic SRS resource set. As part of configuring the SRS resource set, the base station can also configure a downlink reference signal resource slot offset. The downlink reference signal resource can be included in a time slot as indicated by the downlink reference signal resource slot offset. This can provide the UE with enough time to determine the QCL assumption of the downlink reference signal resource and switch beams to measure the downlink reference signal resource. In some cases, the QCL assumption can be based on the beam switching capability of the UE. For example, if the UE has enough time to determine the QCL assumption and switch beams, the UE can apply a transmission configuration indicator (TCI) state associated with the aperiodic downlink reference signal resource. Otherwise, the UE can use a QCL assumption shared by another signal or a default QCL assumption.

[0066] The technology herein also uses a media access control (MAC) control element (CE) to describe a more dynamic configuration and reconfiguration of downlink reference signal resources associated with an SRS resource set. For example, the association between the downlink reference signal resources and the SRS resource set can be configured by RRC signaling. By using a MAC CE to update the association between the SRS resource set and the downlink reference signal resources, the UE can have increased flexibility for adjusting the uplink beam. In some cases, the MAC CE can be used to indicate the TCI state of the downlink reference signal resources, which can also be used to adjust the uplink beam of the UE without configuring new downlink reference signal resources.

[0067] Various aspects of the present disclosure are initially described in the context of a wireless communication system. Various aspects of the present disclosure are further described by and with reference to apparatus diagrams, system diagrams, and flow charts related to beam switching techniques for uplink transmission.

[0068] Figure 1An example of a wireless communication system 100 supporting beam switching techniques for uplink transmissions 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.

[0069] The base stations 105 may be dispersed throughout a geographic area to form the wireless communication system 100 and may be devices in different forms or with different capabilities. The base stations 105 and the UEs 115 may communicate wirelessly via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which the UEs 115 and the base stations 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area in which the base stations 105 and the UEs 115 may support communication of signals according to one or more radio access technologies.

[0070] The 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. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. 1. The UEs 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), such as Figure 1 As shown in .

[0071] Base stations 105 may communicate with core network 130, or with each other, or both. For example, base stations 105 may interface with core network 130 via one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). Base stations 105 may communicate with each other directly (e.g., directly between base stations 105) or indirectly (e.g., via core network 130), or both via backhaul links 120 (e.g., via X2, Xn, or other interfaces). In some examples, backhaul links 120 may be or include one or more wireless links.

[0072] One or more of the base stations 105 described herein may include or may be referred to by a person of ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a next generation NodeB or a giga NodeB (any of which may be referred to as a gNB), a home NodeB, a home eNodeB, or other suitable terminology.

[0073] 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 laptop 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, among other examples, which may be implemented in various objects such as electrical appliances or vehicles, meters, and among other examples.

[0074] The UE 115 described herein may be able to communicate with various types of devices, such as other UEs 115, which may sometimes act as relays, as well as base stations 105 and network devices including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, such as Figure 1 As shown in .

[0075] UE 115 and base station 105 can communicate with each other wirelessly via one or more communication links 125 through one or more carriers. The term "carrier" can refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting communication link 125. For example, a carrier for communication link 125 can include a portion of a radio frequency spectrum band (e.g., a fractional bandwidth (BWP)) operated according to one or more physical layer channels of a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel can carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating the operation of the carrier, user data, or other signaling. The wireless communication system 100 can support communication with UE 115 using carrier aggregation or multi-carrier operation. UE 115 can be configured with multiple downlink component carriers and one or more uplink component carriers according to the carrier aggregation configuration. Carrier aggregation can be used with frequency division duplex (FDD) and time division duplex (TDD) component carriers.

[0076] 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 according to a channel raster to be discovered by a UE 115. A carrier may operate in a standalone mode where initial acquisition and connection may be made by a UE 115 via a carrier, or a carrier may operate in a non-standalone mode using a different carrier (e.g., a different carrier of the same or different radio access technology) to anchor a connection.

[0077] 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 an FDD mode) or may be configured to carry both downlink and uplink communications (e.g., in a TDD mode).

[0078] A carrier may be associated with a particular bandwidth of a radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may 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)). Devices of the wireless communication system 100 (e.g., a base station 105, a UE 115, or both) may have a hardware configuration that supports communication over a particular carrier bandwidth or may be configured to support communication over one of the carrier bandwidth sets. In some examples, the wireless communication system 100 may include a base station 105 or a UE 115 that supports simultaneous communication via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate over a portion (e.g., a subband, a BWP) or all of a carrier bandwidth.

[0079] The signal waveform transmitted through the carrier wave may be composed of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques, 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 be composed of a symbol period (e.g., the duration of a modulation symbol) and a subcarrier, where the symbol period is inversely proportional to the subcarrier spacing. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the code 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. Wireless communication resources may refer to a combination of radio frequency 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 used to communicate with the UE 115.

[0080] One or more numerologies for a carrier may be supported, where the numerologies may include subcarrier spacing (Δf) and cyclic prefixes. A carrier may be divided into one or more BWPs with the same or different numerologies. 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 for a UE 115 may be limited to the one or more active BWPs.

[0081] 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 referred to as 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. The time intervals of the communication resources may be organized according to radio frames, each of which has 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).

[0082] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, the frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into multiple time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include multiple symbol periods (e.g., depending on the length of a cyclic prefix prepended to each symbol period). In some wireless communication systems 100, the time slots may be further divided into multiple mini-time slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0083] A subframe, a time slot, a mini-time slot, or a 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)).

[0084] Physical channels may be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels may be multiplexed on a downlink carrier, for example, using one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique. A control region (e.g., a control resource set (CORESET)) of a physical control channel may be defined by a plurality of symbol periods and may extend across a system bandwidth or a subset of a system bandwidth of a carrier. One or more control regions (e.g., CORESETs) may be configured for a set of UEs 115. For example, one or more of the UEs 115 may monitor or search a control region to obtain control information according to one or more search space sets, and each search space set may 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 may refer to a plurality of control channel resources (e.g., a control channel element (CCE)) associated with coded information of a control information format having a given payload size. A search space set may include a common search space set configured for sending control information to a plurality of UEs 115 and a UE-specific search space set for sending control information to a particular UE 115.

[0085] Each base station 105 may provide communication coverage via one or more cells (e.g., macro cells, small cells, hot spots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with a base station 105 (e.g., via a carrier), and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), etc.) used to distinguish adjacent cells. In some examples, a cell may also refer to a geographic coverage area 110 or a portion of a geographic coverage area 110 (e.g., a sector) on which a logical communication entity operates. Depending on various factors such as the capabilities of the base station 105, the range of such a cell may range from a smaller area (e.g., a structure, a subset of a structure) to a larger area. For example, a cell may be or include a building, a subset of a building, or an external space between or overlapping geographic coverage areas 110, as well as other examples.

[0086] A macro cell typically covers a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access to a UE 115 with a service subscription to a network provider supporting the macro cell. A small cell may be associated with a lower power base station 105 than a macro cell, and the small cell may operate in a frequency band that is the same or different (e.g., authorized, unauthorized) from the macro cell. A small cell may provide unrestricted access to a UE 115 with a service subscription to a network provider, or may provide unrestricted access to a UE 115 associated with a small cell (e.g., a UE 115 in a closed subscriber group (CSG), a UE 115 associated with a user in a home or office). A base station 105 may support one or more cells and may also support communication through one or more cells using one or more component carriers.

[0087] 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)), which may provide access for different types of devices.

[0088] In some examples, base stations 105 may be mobile and thus provide communication coverage for mobile geographic coverage areas 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. The wireless communication system 100 may 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.

[0089] The wireless communication system 100 may support synchronous operation or asynchronous operation. For synchronous operation, the base stations 105 may have similar frame timing, and transmissions from different base stations 105 may be approximately aligned in time. For asynchronous operation, the base stations 105 may have different frame timing, and in some examples, transmissions from different base stations 105 may not be aligned in time. The techniques described herein may be used for either synchronous operation or asynchronous operation.

[0090] 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 the information to a person interacting with the application. Some UEs 115 may be designed to collect information or implement 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 commercial billing.

[0091] Some UEs 115 may be configured to adopt an operating mode that reduces power consumption, 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 UE 115 include entering a power-saving deep sleep mode when not participating in active communication, operating with 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 that is 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 a carrier.

[0092] 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. UE115 can be designed to support ultra-reliable, low-latency or critical functions (e.g., mission-critical functions). Ultra-reliable communication can include dedicated 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 priorities, 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 herein.

[0093] In some examples, UE 115 may also be able to communicate directly with other UE 115 via a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UE 115 utilizing D2D communication may be located within a geographic coverage area 110 of a base station 105. Other UEs 115 in such a group may be located outside the geographic coverage area 110 of a base station 105, or may otherwise be unable to receive transmissions from a base station 105. In some examples, a group of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system, wherein each UE 115 transmits to each other UE 115 in the group. In some examples, a base station 105 facilitates scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without involving a base station 105.

[0094] In some systems, the D2D communication link 135 can be an example of a communication channel such as a sidelink communication channel between vehicles (e.g., UE 115). In some examples, vehicles can communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination of these. Vehicles can use signal notifications 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 via one or more network nodes (e.g., base station 105) using vehicle-to-network (V2N) communication, or both.

[0095] 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)) for managing 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)) for routing or interconnecting packets to an external network. The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for UE 115 served by a base station 105 associated with the core network 130. User IP packets may be transmitted via the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to a network operator IP service 150. The operator IP service 150 may include access to the Internet, an intranet, an IP multimedia subsystem (IMS), or a packet-switched streaming media service.

[0096] Some 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 UE 115 through one or more other access network transport entities 145, which may be referred to as radio heads, smart radio heads, or transmit / receive points (TRPs). Each access network transport 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 merged into a single network device (e.g., base station 105).

[0097] The wireless communication system 100 may 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 wavelengths range from about one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features, but these waves may penetrate structures sufficiently for macro cells to provide service to UEs 115 located indoors. Transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission of smaller frequencies and longer waves using the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

[0098] The wireless communication system 100 may also operate in a super high frequency (SHF) zone (also known as a centimeter band) using a frequency band from 3 GHz to 30 GHz, or in an extremely high frequency (EHF) zone (known as a millimeter band) of a spectrum (e.g., from 30 GHz to 300 GHz). In some examples, the wireless communication system 100 may support millimeter wave (mmW) communications between a UE 115 and a base station 105, and the EHF antennas of the corresponding devices may be smaller and more closely spaced than 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 more atmospheric attenuation and shorter range limitations than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions using one or more different frequency zones, and the designated use of bands across these frequency zones may vary by country or regulatory agency.

[0099] The wireless communication system 100 can utilize both licensed radio frequency spectrum bands and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 can adopt licensed assisted access (LAA), LTE-unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band such as the 5GHz industrial, scientific, and medical (ISM) band. When operating in an unlicensed radio frequency spectrum band, devices such as base stations 105 and UEs 115 can use carrier sensing for conflict detection and avoidance. In some examples, operations in unlicensed bands can be based on a carrier aggregation configuration combined with component carriers operating in a licensed band (e.g., LAA). Operations in unlicensed spectrum can include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, as well as other examples.

[0100] The base station 105 or 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 the base station 105 or UE 115 may be located within one or more antenna arrays or antenna panels, which 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, antennas or antenna arrays associated with the base station 105 may be located in different geographic locations. The base station 105 may have an antenna array with multiple rows and columns of antenna ports, which the base station 105 may use to support beamforming for communications with the UE 115. Similarly, the UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals sent via the antenna ports.

[0101] 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. Such technology can be referred to as spatial multiplexing. Multiple signals can be sent, for example, by a transmitting device via different antennas or different antenna combinations. Similarly, multiple signals can be received by a receiving device via different antennas or different antenna combinations. Each of the multiple signals can be referred to as a separate spatial stream and can carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers can be associated with different antenna ports for channel measurement and reporting. MIMO technology includes single-user MIMO (SU-MIMO) that sends multiple spatial layers to the same receiving device and multi-user MIMO (MU-MIMO) that sends multiple spatial layers to multiple devices.

[0102] 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 an antenna beam (e.g., a transmit beam, a receive beam) or steer the antenna beam along a spatial path between the transmitting device and the receiving device. Beamforming can be achieved by combining signals transmitted via antenna elements of an antenna array so that some signals propagating at a specific orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals transmitted via antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each of the antenna elements may be defined by a set of beamforming weights associated with a specific orientation (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other orientation).

[0103] The base station 105 or the UE 115 may use beam scanning 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. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be sent multiple times by the base station 105 in different directions. For example, the base station 105 may send signals according to different sets of beamforming weights associated with different transmission directions. Transmissions in different beam directions may be used to identify (e.g., by a transmitting device such as the base station 105 or by a receiving device such as the UE 115) a beam direction that is later transmitted or received by the base station 105.

[0104] Some signals, such as data signals associated with a particular receiving device, may be sent 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, a beam direction associated with transmissions along a single beam direction may be determined based on signals sent in one or more beam directions. For example, UE 115 may receive one or more of the signals sent 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.

[0105] In some examples, transmissions by a device (e.g., by a base station 105 or a UE 115) may be performed using multiple beam directions, and the device may generate a combined beam for transmission (e.g., from a base station 105 to a UE 115) using a combination of digital precoding or radio frequency beamforming. The UE 115 may report feedback indicating precoding weights 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. The base station 105 may send reference signals (e.g., cell-specific reference signals (CRS), CSI-RS) that may be precoded or not precoded. The 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 codebook, a linear combination codebook, a port selection 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 to send signals multiple times in different directions (e.g., to identify a beam direction for subsequent transmission or reception by UE 115) or to send signals in a single direction (e.g., to send data to a receiving device).

[0106] A receiving device (e.g., UE 115) may try multiple reception configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from a base station 105. For example, a receiving device may try multiple reception directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different reception beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or by processing received signals according to different reception beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as "listening" according to different reception configurations or reception directions. In some examples, a receiving device may use a single reception configuration to receive along a single beam direction (e.g., when receiving a data signal). A single reception configuration may be aligned on a beam direction determined based on listening according to different reception configuration directions (e.g., a beam direction determined to have the highest signal strength, the highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0107] The wireless communication system 100 can be a packet-based network operating according to a layered protocol stack. In the user plane, the communication 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 reorganization to communicate through logical channels. The media 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 the RRC connection between the UE 115 and the base station 105 or the core network 130 that supports the radio bearer of the user plane data. At the physical layer, the transport channel can be mapped to the physical channel.

[0108] UE 115 and base station 105 can support retransmission of data to increase the possibility of successfully receiving data. Hybrid automatic repeat request (HARQ) feedback is a technology for increasing the possibility of correctly receiving data through communication link 125. HARQ can include a combination of error detection (e.g., using cyclic redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ can improve the throughput at the MAC layer under poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, the device can support simultaneous slot HARQ feedback, wherein the device can provide HARQ feedback for data received in the previous symbol in the slot in a specific time slot. In other cases, the device can provide HARQ feedback in subsequent time slots or according to some other time interval.

[0109] UE 115 can be configured for non-codebook based uplink transmission. For non-codebook based uplink transmission, UE 115 can determine the uplink pre-decoder for sending on the SRS resource set based on the measurement of downlink reference signal resources such as CSI-RS. UE 115 can measure the downlink reference signal resources and calculate the uplink pre-decoder based on the measurement. Base station 105 can configure SRS resource sets and associated downlink reference signal resources. In some cases, the SRS resource set can include up to four SRS resources. The configuration can indicate that the SRS resource set is configured for non-codebook use. Other uses of non-periodic SRS resource sets may include codebook use, beam management use, and antenna switching. In some cases, the SRS resource set can be configured by RRC.

[0110] In some cases, the SRS resource set and the downlink reference signal resource can be non-periodic. The base station 105 can send DCI to trigger the downlink reference signal resource and one or more SRS resource sets. In some cases, the non-periodic SRS can be triggered by a certain format of DCI (e.g., a downlink DCI with a format of 1_1 or 1_2, an uplink DCI with a format of 0_1 or 0_2, or a group common DCI with a format of 2_3). For example, the SRS request field in the DCI can indicate one or more SRS resource sets. The UE 115 can measure the downlink reference signal resource, calculate the pre-decoder based on the downlink reference signal resource, and send the SRS on the SRS resource indicated by the SRS request field. The DCI can schedule uplink shared channel transmission, and the UE 115 can use the same uplink pre-decoder and spatial domain filter (e.g., beam) as used for the indicated SRS resource.

[0111] The base station 105 receives the pre-decoded SRS resources and selects one or more of the SRS resources to indicate in the uplink DCI for scheduling of an uplink shared channel (e.g., a physical uplink shared channel (PUSCH)). The base station 105 may send an uplink DCI with an SRS resource indicator indicating one or more of the SRS resources sent by the UE 115. The UE 115 may transmit on the uplink shared channel using the same pre-decoder and spatial domain filter as the indicated SRS resources. The number of SRS resources indicated by the SRS resource indicator may determine the rank (e.g., number of layers) of the uplink transmission. In some cases, there may be a mapping between an SRS resource set and an SRS request field code point, which may be indicated by a field such as aperiodicSRS-ResourceTrigger or aperiodicSRS-ResourceTriggerList.

[0112] Aperiodic SRS resource sets may be configured with a slot offset. The SRS slot offset may be included as part of configuring aperiodic SRS resources that may be configured with aperiodic SRS resources. The aperiodic SRS resource slot offset may indicate that the SRS resources in the SRS resource set are transmitted a number of slots after the slot in which the triggering DCI is received. For example, if the aperiodic SRS slot offset is 4, then the SRS resources in the aperiodic SRS resource set are transmitted 4 slots after the slot carrying the triggering DCI.

[0113] The base station 105 may also configure a downlink reference signal resource slot offset for the UE 115. The downlink reference signal resource may be included in a time slot as indicated by the downlink reference signal resource slot offset. The time slot offset of the downlink reference resource may provide the UE 115 with sufficient time to determine the QCL assumption for the downlink reference signal resource and switch beams to measure the downlink reference signal resource. In some cases, the QCL assumption may be based on the beam switching capability of the UE 115. For example, if the UE 115 has sufficient time to determine the QCL assumption and switch beams, the UE 115 may apply a TCI state associated with the non-periodic downlink reference signal resource. Otherwise, the UE 115 may use a QCL assumption shared by another signal or a default QCL assumption.

[0114] The techniques herein also use MAC CE to describe a more dynamic configuration and reconfiguration of downlink reference signal resources associated with SRS resource sets. For example, the association between downlink reference signal resources and SRS resource sets can be configured by RRC signaling. By using MAC CE to update the association between SRS resource sets and downlink reference signal resources, UE115 can have increased flexibility for adjusting uplink beams. In some cases, MAC CE can be used to indicate the TCI state of the downlink reference signal resources, which can also be used to adjust the uplink beam of UE 115 without configuring new downlink reference signal resources.

[0115] Figure 2 An example of a wireless communication system 200 supporting beam switching techniques for uplink transmission according to aspects of the present disclosure is illustrated. In some examples, the wireless communication system 200 may implement aspects of the wireless communication system 100. For example, the wireless communication system 200 may include a base station 205 and a UE 215, which may be a reference Figure 1 The base station 205 and the UE 115 are described with reference to the accompanying drawings. As described herein, the base station 205 can configure SRS resources for the UE 215, the UE 215 can transmit SRS using the configured SRS resources, and the base station 205 can indicate one or more of the SRS resources for the UE 215 to select a transmission configuration for an associated uplink transmission.

[0116] In some examples, UE 215 may be configured for non-codebook based uplink transmissions. For non-codebook based uplink transmissions, UE 215 may determine an uplink pre-decoder for transmission on SRS resource set 235 based on measurements of downlink reference signal resources 210 such as CSI-RS. UE 215 may measure downlink reference signal resources 210 and calculate an uplink pre-decoder based on the measurements. An uplink pre-decoder for codebook based uplink transmissions for comparison may be selected based on an indication of an index in a codebook or a value in a pre-decoder matrix configured at UE 115 (e.g., from base station 105). In some cases, for non-codebook based uplink transmissions, base station 105 may not have configured a transmission pre-decoder matrix for UE 115 or may not have sent a transmission pre-decoder matrix indicator.

[0117] The base station 205 may send configuration information 230 to configure the SRS resource set 235 and the downlink reference signal resource 210. In some cases, the SRS resource set 235 may include up to four SRS resources. The configuration information 230 may indicate that the SRS resource set 235 is configured for non-codebook use (e.g., based on the configuration of the "use" parameter in the configuration information 230). In some cases, the UE 115 may be configured with only one SRS resource set 235 for non-codebook communication. In some cases, the configuration information 230 may be sent by RRC signaling.

[0118] Configuration information 230 may include an indicator of downlink reference signal resources 210. In some cases, configuration information 230 may include a configuration associating an SRS resource set 235 with downlink reference signal resources 210. In some cases, downlink reference signal resources 210 may be non-zero power CSI-RS resources.

[0119] In some cases, the SRS resource sets 235 and the downlink reference signal resources 210 may be aperiodic. The base station 205 may send a DCI 220 to the UE 215 to trigger the downlink reference signal resources 210 and one or more SRS resource sets 235. For example, the SRS request field in the DCI 220 may indicate one or more SRS resource sets, including an SRS resource set 235 with usage set to non-codebook. The UE 215 may measure the downlink reference signal resources 210, calculate a precoder based on the downlink reference signal resources 210, and send an SRS on the SRS resources.

[0120] The aperiodic SRS resource set may be configured with a slot offset. The SRS slot offset may be included as part of configuring the aperiodic SRS resource set. The aperiodic SRS slot offset may indicate that the SRS resources in the SRS resource set are transmitted a number of slots after the slot in which the DCI 220 is received. For example, if the aperiodic SRS slot offset is 4, then the SRS resources in the aperiodic SRS resource set are transmitted 4 slots after the slot carrying the DCI 220.

[0121] In some systems, the aperiodic downlink reference signal resources 210 may be located in the same timeslot as the DCI 220. However, in some cases, the UE 115 may communicate using the spatial quasi-co-location (QCL) assumption. If the aperiodic downlink reference signal resources 210 are located in the same timeslot as the DCI 220 (e.g., scheduling communications), the transmission configuration indicator (TCI) state of the UE 115 may not be configured with the spatial QCL assumption. Therefore, if the aperiodic downlink reference signal resources 210 are located in the same timeslot as the DCI 220, the UE 115 may not have enough time to switch beams to receive the aperiodic downlink reference signal resources 210. For example, a UE 115 operating in frequency range 2 (FR2) may communicate using the QCL type D assumption. Thus, UEs 115 operating in FR2 in some systems may not be able to support aperiodic non-codebook based uplink transmissions because UEs 115 in these systems may not be able to switch beams and apply the spatial QCL assumption to receive downlink reference signal resources.

[0122] The wireless communication system 200 supports techniques for enhanced uplink beam switching. For example, these techniques can be implemented by the UE 115 as an uplink precoder that determines and applies QCL assumptions to measure aperiodic CSI-RS resources and determine an associated aperiodic SRS resource set.

[0123] As part of the RRC configuration of the SRS resource set 235, the base station 205 may also configure a CSI-RS slot offset applied to the associated downlink reference signal resources. The CSI-RS slot offset may be indicated by a parameter such as "SlotOffset-CSI-RS" in the configuration information 230. The slot offset of the CSI-RS resource may be different from the slot offset of the SRS resource set 235. In some cases, there may be at least 42 symbol gaps between the associated CSI-RS and the SRS resource set 235. In some cases, the CSI-RS slot offset may be less than the SRS resource set slot offset.

[0124] For example, the UE 215 may be configured with a downlink reference signal resource 210 and an SRS resource set 235, which may be aperiodic. The configuration information 230 configuring the resources may include a slot offset associated with the downlink reference signal resource 210. The downlink reference signal resource 210 may be included in a slot as indicated by the downlink reference signal resource slot offset. This may provide the UE 215 with sufficient time to determine a QCL hypothesis for the downlink reference signal resource 210 and switch beams to measure the downlink reference signal resource 210.

[0125] The base station 205 may transmit the DCI 220 to the UE 215 using an SRS request field indicating an SRS resource set 235 having a downlink reference signal resource 210 as an associated CSI-RS resource. The UE 215 may be configured with a slot offset for the downlink reference signal resource 210. The UE 215 may then determine which slot includes the downlink reference signal resource 210 based on the slot offset for the downlink reference signal resource 210. For example, if the CSI-RS slot offset is "1", then the downlink reference signal resource 210 may be located in the next slot after the DCI 220.

[0126] The UE 215 may determine a QCL assumption for the downlink reference signal resource 210 and monitor the downlink reference signal on the downlink reference signal resource 210. For example, the downlink reference signal resource 210 may be associated with a TCI state. The UE 215 may apply a QCL assumption associated with the TCI state (e.g., a spatial QCL assumption or a type D QCL assumption) to monitor the downlink reference signal resource 210. In some cases, the downlink reference signal resource 210 may have an associated beam configuration or a spatial QCL assumption configuration.

[0127] In some cases, the QCL assumption used by the UE 215 to monitor the downlink reference signal resources 210 may be based on the beam switching capability of the UE 215. For example, if the scheduling offset between the DCI 220 and the downlink reference signal resources 210 is greater than or equal to the beam switching capability of the UE 215, then the UE 215 may apply the TCI state of the associated CSI-RS resource. However, if the scheduling offset is less than the beam switching capability of the UE 215, then the UE 215 may not have sufficient time to determine and apply the TCI state before the downlink reference signal resources 210 begin. In some cases, the TCI state of the aperiodic CSI-RS resource may be configured as part of the CSI-RS resource configuration.

[0128] If the scheduling offset is greater than the number of time slots corresponding to the beam switching capability, the UE 215 may apply a technique to determine a QCL assumption for receiving the downlink reference signal resource 210. For example, if there is another downlink signal in the same symbol as the associated CSI-RS, the UE 215 may apply the QCL assumption of the other downlink signal to the reception of the CSI-RS resource. In some cases, the UE 215 may use a default QCL assumption. The default QCL assumption may be the QCL assumption of the lowest control resource set identifier in the most recent time slot in which the UE 215 monitors one or more control resource sets.

[0129] In some cases, the UE 215 may monitor the downlink reference signal resources 210 regardless of the QCL type of the configured TCI state of the serving cell index. In some cases, if no configured TCI state has QCL type D, then the CSI-RS slot offset value may be ignored (e.g., the UE 215 assumes that the CSI-RS slot offset is "0"). For example, if the UE 215 is not operating in FR2, then the UE 215 may assume that the CSI-RS slot offset is 0.

[0130] Additional techniques for associating CSI-RS resources with SRS resource sets are described herein. For example, a CSI-RS associated with an SRS resource set for non-codebook communication may be configured via RRC. The UE 115 then transmits the target SRS resources in the resource set and transmits a scheduled uplink shared channel using the same spatial domain transmission filter (e.g., uplink beam) used to receive the associated CSI-RS resources. The uplink beam may not change unless the associated CSI-RS of the SRS resource set changes. However, as described, some systems only support changing CSI-RS resources via RRC configuration and reconfiguration, which may be slow and result in inefficiencies.

[0131] The wireless communication system 200 may provide a technique for a base station to send a MAC CE indicating a CSI-RS resource of an SRS resource set. The MAC CE may enable more dynamic configuration and reconfiguration of downlink reference signal resources associated with an SRS resource set. Indicating CSI-RS resources via a MAC CE may be used for a periodic SRS resource set, a semi-persistent SRS resource set, or an aperiodic SRS resource set. The command may be applied shortly after sending feedback corresponding to a downlink shared channel message including a MAC CE (e.g., 3 ms after sending the feedback).

[0132] The MAC CE may indicate a CSI-RS resource identifier. In some cases, the MAC CE may indicate an SRS resource set ID (e.g., if more than one SRS resource set for non-codebook use is supported), a serving cell index, a bandwidth portion identifier, or a combination thereof. In some cases, the MAC CE may indicate the characteristics of an SRS resource set. For example, the MAC CE may indicate a non-periodic SRS resource trigger or a list of non-periodic SRS resource triggers, a time slot offset value for SRS transmission, or a time slot offset value for CSI-RS. Additionally or alternatively, the MAC CE may indicate a TCI state identifier for the CSI-RS. For example, instead of indicating a different or additional CSI-RS resource, the MAC CE may update or indicate the TCI state of an already configured CSI-RS resource.

[0133] Figure 3 An example of an aperiodic SRS resource set configuration 300 that supports beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated. In some examples, the aperiodic SRS resource set configuration 300 can implement aspects of the wireless communication system 100.

[0134] As reference Figure 2 As described, the UE 115 may be configured with an aperiodic SRS resource set 315 for a non-codebook uplink. The aperiodic SRS resource set 315 may be associated with a CSI-RS resource 310, which may be used to send a non-zero power CSI-RS. The SRS resource set 315 and the CSI-RS resource may be configured for the UE 115 by the base station 105. For example, the SRS resource set configuration may be configured by RRC. In some cases, the UE 115 may be configured with a slot offset for the SRS resource set 315. The slot offset for the SRS resource set may indicate how many slots 330 there are between the DCI 305 that triggers the aperiodic SRS resource set and the SRS resource set 315. For example, if the slot offset for the SRS resource set is 4, then the SRS resource set 315 may be located in the fourth slot of the DCI 305.

[0135] Wireless communication systems such as the wireless communication system 200 described herein support the base station 105 configuring a slot offset of the CSI-RS resource 310 for the UE 115. The slot offset of the CSI-RS resource 310 may indicate the number of slots between the DCI 305 and the CSI-RS resource 310. By providing a slot offset between the DCI 305 and the CSI-RS resource 310, the UE 115 may have enough time to perform beam switching and measure the CSI-RS using the spatial QCL assumption.

[0136] For example, UE 115 may receive DCI 305 that triggers CSI-RS resource 310 and SRS resource set 315. UE 115 may recognize that the slot offset of CSI-RS resource 310 is "1" and determine that CSI-RS resource 310 is located in the next slot 330. In some cases, there may be at least a configured number of symbol periods between CSI-RS resource 310 and SRS resource set 315. For example, there may be at least 42 symbol periods between CSI-RS resource 310 and SRS resource set 315.

[0137] The UE 115 may determine a scheduling offset 335 between the DCI 305 and the CSI-RS resource 310. The scheduling offset 335 may be based on the number of symbols between the last symbol of the DCI 305 and the first symbol of the CSI-RS resource 310. The UE 115 may then compare the scheduling offset 335 to the beam switching capability of the UE 115.

[0138] If the beam switching capability of UE 115 is less than the scheduling offset 335, then UE 115 may apply the TCI state of CSI-RS resource 310. The TCI state may include one or more QCL assumption configurations, including a spatial QCL assumption or a type D QCL assumption. In some cases, the TCI state of CSI-RS resource 310 may be RRC configured (e.g., as part of configuring the CSI-RS resource).

[0139] If the number of symbol periods corresponding to the beam switching capability of UE 115 is greater than the scheduling offset 335, then UE 115 may implement a technique to determine a QCL assumption for receiving CSI-RS resource 310. For example, there may not be enough symbol periods between DCI 305 of UE 115 and CSI-RS resource 310 to determine the TCI state and switch beams. In some cases, if there is another downlink signal that overlaps with the CSI-RS of CSI-RS resource 310, then UE 115 may apply the QCL assumption of the other downlink signal to monitor CSI-RS resource 310. In some cases, UE 115 may apply a default QCL assumption based on the QCL assumption of the lowest ID control resource set of the control resource sets monitored in the most recent time slot.

[0140] The UE 115 may then monitor the CSI-RS resources 310 and calculate an uplink precoder for the SRS resource set 315 based on the measurement of the CSI-RS resources 310. The DCI 305 may include an SRS request field that indicates one or more SRS resource sets (e.g., including an SRS resource set with a usage parameter configured as non-codebook). The UE 115 may use the calculated precoder to send an SRS on the SRS resources in the indicated SRS resource set.

[0141] The base station 105 may receive the pre-coded SRS resources and select one or more SRS resources to indicate in the uplink DCI 320 for uplink shared channel scheduling. The base station 105 may send the uplink DCI 320 to the UE 115 using the SRS resource indicator field, which indicates one or more of the SRS resources in the SRS resource set 315. For example, the SRS resource indicator field may indicate SRS resources 0 and 2. Based on the SRS resource indicator field indicating two SRS resources, the uplink shared channel 325 may have two layers, each of which is sent using the same precoding and beam as the precoding and beam used to send SRS resources 0 and 2. The UE 115 may then send the uplink shared channel 325 based on the indicated SRS resources.

[0142] Figure 4 An example of a process flow 400 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated. In some examples, the process flow 400 can implement aspects of the wireless communication system 100. The process flow 400 includes a UE 415 and a base station 405, which can be a reference Figures 1 to 3 1 and 10. As described herein, the base station 405 may configure SRS resources for the UE 415. The UE 415 may transmit an SRS using the configured SRS resources, and the base station 405 may indicate one or more of the SRS resources for the UE 415 to select a transmission configuration for an associated uplink transmission.

[0143] The base station 405 may send an SRS resource set configuration at 410. The SRS resource set configuration may indicate an aperiodic SRS resource set, an aperiodic downlink reference signal resource associated with the aperiodic SRS resource set, and a slot offset associated with the aperiodic downlink reference signal resource. In some cases, the aperiodic downlink reference signal resource may be an aperiodic CSI-RS resource, which may be allocated for transmission of an NZP CSI-RS.

[0144] At 420, the base station 405 may send a DCI in the first time slot, the DCI indicating that the aperiodic SRS resource set is triggered. The DCI may be, for example, an uplink-based DCI, a downlink-based DCI, or a group-common DCI. The DCI may include an SRS request field indicating one or more SRS resource sets (including at least an aperiodic SRS resource set).

[0145] At 425, UE 415 may determine a QCL hypothesis for the aperiodic downlink reference signal resource based on a slot offset associated with the aperiodic downlink reference signal resource. For example, UE 415 may determine a scheduling offset for the aperiodic downlink reference signal resource based on the slot offset, where the scheduling offset corresponds to a number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the aperiodic downlink reference signal resource.

[0146] In some cases, the UE 415 may determine that the beam switching capability of the UE 415 is less than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resource. The UE 415 may then identify a TCI state for the aperiodic downlink reference signal resource, where the QCL assumption is associated with the TCI state for the aperiodic downlink reference signal resource based on the beam switching capability being less than the scheduling offset. For example, if the beam switching capability indicates that the UE 415 can switch beams within the scheduling offset, the UE 415 may apply the TCI state for the CSI-RS resource.

[0147] In some cases, UE 415 may determine that the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resource. In some examples, UE 415 may detect a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, and a QCL assumption may be associated with the downlink signal based on the beam switching capability being greater than the scheduling offset. In some examples, such as if there is no overlapping downlink signal, then in the case where the beam switching capability is greater than the scheduling offset, UE 415 may identify a default QCL assumption.

[0148] At 430, the base station 405 may send a CSI-RS on the CSI-RS resource. The UE 415 may measure the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the QCL assumption. For example, the time slot offset of the CSI-RS may indicate that the CSI-RS is located in the next time slot after the first time slot with the DCI. The UE 415 may apply the determined QCL assumption and monitor the CSI-RS resource in the indicated time slot.

[0149] At 435, UE 415 may determine an uplink precoder for an aperiodic SRS resource set based on the measurement of the aperiodic CSI-RS resource. At 440, UE 415 may send SRS on the SRS resource indicated by the SRS request field indicator (e.g., included in the DCI). UE 415 may use the precoder calculated based on the aperiodic CSI-RS measurement for SRS transmission.

[0150] Figure 5 An example of a process flow 500 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is illustrated. In some examples, the process flow 500 can implement aspects of the wireless communication system 100. The process flow 500 includes a UE 515 and a base station 505, which can be a reference Figures 1 to 4 1 and 10. As described herein, the base station 505 may configure SRS resources for the UE 515. The UE 515 may transmit an SRS using the configured SRS resources, and the base station 505 may indicate one or more of the SRS resources for the UE 515 to select a transmission configuration for an associated uplink transmission.

[0151] The base station 505 may send an SRS resource set configuration at 510. The SRS resource set configuration may indicate an SRS resource set. In some cases, the SRS resource set configuration may indicate an NZP downlink reference signal resource associated with the SRS resource set. In some cases, the SRS resource set may be an aperiodic SRS resource set. In some cases, the SRS resource set may be a periodic or semi-persistent SRS resource set.

[0152] At 520, the base station 505 may send a MAC CE indicating downlink reference signal resources associated with the SRS resource set. In some cases, the MAC CE may include an NZP CSI-RS identifier for the downlink reference signal resources, a sounding reference signal resource set identifier for the sounding reference signal resource set, a serving cell index, a bandwidth part identifier, or a combination thereof.

[0153] In some cases, such as if the SRS resource set is an aperiodic SRS resource set, the MAC CE may include an indicator of an aperiodic resource trigger for the SRS resource set, a list of aperiodic resource triggers for the SRS resource set, a time slot offset value for the SRS resource set, a time slot offset for a downlink reference signal resource (e.g., as referenced to Figure 4 described) or a combination thereof.

[0154] At 525, the UE 515 may determine a QCL assumption for the downlink reference signal resources. For example, the downlink reference signal resources may be associated with a TCI state, and the UE 515 may use the QCL assumption for the TCI state. In some cases, the MAC CE may indicate the TCI state of the downlink reference signal resources. For example, the UE 515 may be configured with downlink reference signal resources via the SRS resource set configuration at 510, and the MAC CE received at 520 may indicate the TCI state of the downlink reference signal resources.

[0155] By sending a MAC CE to indicate a downlink reference signal resource or a TCI state of a downlink reference signal resource, the UE 515 may be able to switch uplink beams for an SRS resource set. For example, a downlink reference signal resource configured with a TCI state having a more reliable or stronger beam may be indicated to the UE 515. Thus, by using a MAC CE, the UE 515 may quickly switch uplink beams instead of waiting for RRC reconfiguration.

[0156] At 530, the base station 505 may send a CSI-RS on the CSI-RS resources. The UE 515 may measure the downlink reference signal resources based on the QCL assumption. At 535, the UE 515 may determine an uplink precoder for an aperiodic SRS resource set based on the measurement of the aperiodic CSI-RS resources. At 540, the UE 515 may send an SRS on the SRS resources indicated by the SRS request field indicator (e.g., included in the DCI). The UE 515 may use the precoder calculated based on the aperiodic CSI-RS measurement for SRS transmission.

[0157] Figure 6 A block diagram 600 of a device 605 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 605 may be an example of aspects of a UE 115 as described herein. The device 605 may include a receiver 610, a communication manager 615, and a transmitter 620. The device 605 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0158] The receiver 610 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to beam switching techniques for uplink transmissions, etc.). The information may be passed to other components of the device 605. The receiver 610 may be a reference Fig. 9 Examples of aspects of transceiver 920 are described. Receiver 610 may utilize a single antenna or a collection of antennas.

[0159] The communication manager 615 may receive a sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource; receive downlink control information in a first slot indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption for the aperiodic downlink reference signal resource based on the slot offset associated with the aperiodic downlink reference signal resource; and measure the aperiodic downlink reference signal resource in a second slot indicated by the slot offset based on the quasi-co-location assumption. The communication manager 615 may also receive a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with the sounding reference signal resource set; determine a quasi-co-location assumption for the downlink reference signal resource; and measure the downlink reference signal resource based on the quasi-co-location assumption. The communication manager 615 may be an example of aspects of the communication manager 910 described herein.

[0160] The communication manager 615 or its subcomponents may be implemented using hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented using code executed by a processor, the functions of the communication manager 615 or its subcomponents may be performed by a general purpose processor, DSP, application specific integrated circuit (ASIC), FPGA or other programmable logic device designed to perform the functions described in this disclosure, discrete gate or transistor logic, discrete hardware components, or any combination thereof.

[0161] The communication manager 615 or its subcomponents can be physically located in a variety of locations, including being distributed so that portions of the functionality are implemented by one or more physical components at different physical locations. In some examples, the communication manager 615 or its subcomponents can be separate and distinct components according to various aspects of the present disclosure. In some examples, the communication manager 615 or its subcomponents can be combined with one or more other hardware components, including but not limited to input / output (I / O) components according to various aspects of the present disclosure, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof.

[0162] The actions performed by the UE communication manager 615 as described herein may be implemented to achieve one or more potential advantages. One embodiment may allow the UE 115 to switch beams to measure aperiodic downlink reference signal resources associated with aperiodic SRS resource sets. This may enable the UE 115 to determine a pre-decoder for non-codebook based uplink transmissions based on measuring the aperiodic downlink reference signal resources. Without applying the spatial QCL assumption to measure the downlink reference signal resources, the UE 115 may not be able to measure the downlink reference signal resources, or the measurement may not be directional. By providing a gap between triggering the DCI and the downlink reference signal measurement, the UE 115 may be able to switch beams in time to apply the QCL assumption and measure the downlink reference signal resources.

[0163] Transmitter 620 can transmit signals generated by other components of device 605. In some examples, transmitter 620 can be co-located with receiver 610 in a transceiver module. For example, transmitter 620 can be a reference Fig. 9 Examples of aspects of the transceiver 920 are described. The transmitter 620 may utilize a single antenna or a collection of antennas.

[0164] Figure 7 A block diagram 700 of a device 705 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 705 may be an example of aspects of the device 605 or UE 115 as described herein. The device 705 may include a receiver 710, a communication manager 715, and a transmitter 745. The device 705 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0165] The receiver 710 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to beam switching techniques for uplink transmissions, etc.). The information may be passed to other components of the device 705. The receiver 710 may be a reference Fig. 9 Examples of aspects of the transceiver 920 are described. The receiver 710 may utilize a single antenna or a collection of antennas.

[0166] The communication manager 715 may be an example of aspects of the communication manager 615 as described herein. The communication manager 715 may include an SRS resource set configuration component 720, a DCI reception component 725, a QCL hypothesis determination component 730, a measurement component 735, and a MAC CE reception component 740. The communication manager 715 may be an example of aspects of the communication manager 910 as described herein.

[0167] The SRS resource set configuration component 720 may receive sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource.

[0168] The DCI receiving component 725 may receive downlink control information in a first time slot, the downlink control information indicating that an aperiodic sounding reference signal resource set is triggered.

[0169] QCL hypothesis determining component 730 can determine a quasi co-location hypothesis for the aperiodic downlink reference signal resource based on a slot offset associated with the aperiodic downlink reference signal resource. Measuring component 735 can measure the aperiodic downlink reference signal resource in a second slot indicated by the slot offset based on the quasi co-location hypothesis.

[0170] MAC CE receiving component 740 may receive a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set. QCL hypothesis determining component 730 may determine a quasi co-location hypothesis for the downlink reference signal resources. Measurement component 735 may measure the downlink reference signal resources based on the quasi co-location hypothesis.

[0171] Transmitter 745 can transmit signals generated by other components of device 705. In some examples, transmitter 745 can be co-located with receiver 710 in a transceiver module. For example, transmitter 745 can be a reference Fig. 9 Examples of aspects of the transceiver 920 are described. The transmitter 745 may utilize a single antenna or a collection of antennas.

[0172] Figure 8 A block diagram 800 of a communication manager 805 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The communication manager 805 may be an example of aspects of the communication manager 615, the communication manager 715, or the communication manager 910 described herein. The communication manager 805 may include an SRS resource set configuration component 810, a DCI reception component 815, a QCL hypothesis determination component 820, a measurement component 825, a MAC CE reception component 830, and a MAC CE command application component 835. Each of these modules may be in communication with each other directly or indirectly (e.g., via one or more buses).

[0173] The SRS resource set configuration component 810 may receive sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource.

[0174] In some examples, the SRS resource set configuration component 810 can determine a scheduling offset for the aperiodic downlink reference signal resource based on the slot offset, wherein the scheduling offset corresponds to a number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the aperiodic downlink reference signal resource. In some examples, the SRS resource set configuration component 810 can identify a configured TCI state set.

[0175] In some examples, the SRS resource set configuration component 810 can determine that all configured TCI states in the set of configured TCI states are not associated with the spatial quasi co-location assumption. In some examples, the SRS resource set configuration component 810 can determine a time slot offset of zero, wherein the non-periodic downlink reference signal resource is located in a first time slot having downlink control information.

[0176] In some cases, the aperiodic sounding reference signal resource set configuration information is received in a radio resource control configuration. In some cases, the aperiodic downlink reference signal resources include aperiodic channel state information reference signal resources.

[0177] The DCI receiving component 815 may receive downlink control information in the first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered. In some cases, the downlink control information includes group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

[0178] In some cases, the aperiodic downlink reference signal resources are triggered based on a sounding reference signal request field in the downlink control information. The QCL hypothesis determination component 820 can determine a quasi-co-location hypothesis for the aperiodic downlink reference signal resources based on a slot offset associated with the aperiodic downlink reference signal resources. In some examples, the QCL hypothesis determination component 820 can determine a quasi-co-location hypothesis for the downlink reference signal resources.

[0179] In some examples, QCL hypothesis determining component 820 can determine that the beam switching capability of the UE is less than a scheduling offset between the downlink control information and the aperiodic downlink reference signal resources. In some examples, QCL hypothesis determining component 820 can identify a TCI state of the aperiodic downlink reference signal resources, wherein the quasi-co-location hypothesis is associated with the TCI state of the aperiodic downlink reference signal resources based on the beam switching capability being less than the scheduling offset.

[0180] In some examples, the QCL hypothesis determination component 820 can determine that the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resource. In some examples, the QCL hypothesis determination component 820 can detect a downlink signal scheduled to overlap with the non-periodic downlink reference signal resource, wherein the quasi-co-location assumption is associated with the downlink signal based on the beam switching capability being greater than the scheduling offset. In some examples, the QCL hypothesis determination component 820 can identify a default quasi-co-location assumption, wherein the quasi-co-location assumption is the default quasi-co-location assumption based on the beam switching capability being greater than the scheduling offset. In some examples, the QCL hypothesis determination component 820 can receive a configuration of the non-periodic downlink reference signal resource, the configuration comprising a TCI state associated with the non-periodic downlink reference signal resource.

[0181] In some examples, the QCL hypothesis determining component 820 can receive a TCI state of a downlink reference signal resource by a MAC CE, wherein the quasi co-location hypothesis is based on the TCI state of the downlink reference signal resource. In some cases, the default quasi co-location hypothesis is associated with a control resource set having a lowest control resource identifier among the control resource sets monitored in the latest time slot.

[0182] Measuring component 825 can measure the aperiodic downlink reference signal resources in the second time slot indicated by the time slot offset based on the quasi co-location assumption.In some examples, measuring component 825 can measure the downlink reference signal resources based on the quasi co-location assumption.

[0183] The MAC CE receiving component 830 may receive a MAC CE indicating a downlink reference signal resource associated with a sounding reference signal resource set. In some cases, the MAC CE includes a non-zero power (NZP) CSI-RS identifier for the downlink reference signal resource, a sounding reference signal resource set identifier for the sounding reference signal resource set, a serving cell index, a bandwidth portion identifier, or a combination thereof.

[0184] In some cases, the MAC CE includes an indicator of an aperiodic resource trigger for a sounding reference signal resource set, a list of aperiodic resource triggers for a sounding reference signal resource set, a slot offset value for a sounding reference signal resource set, a slot offset for a downlink reference signal resource, or a combination thereof. In some cases, the sounding reference signal resource set is an aperiodic resource set, a periodic resource set, or a semi-persistent resource set. The MAC CE command application component 835 can apply a command associated with the MAC CE after sending feedback of a downlink shared channel message including the MAC CE.

[0185] Fig. 9 A diagram of a system 900 including a device 905 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 905 may be an example of or include components of a device 605, a device 705, or a UE 115 as described herein. The device 905 may include components for two-way voice and data communications including components for sending and receiving communications, including a communication manager 910, an I / O controller 915, a transceiver 920, an antenna 925, a memory 930, and a processor 940. These components may be in electronic communication via one or more buses (e.g., a bus 945).

[0186] The communication manager 910 may receive a sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; receive downlink control information in a first time slot indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption for the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and measure the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based on the quasi-co-location assumption. The communication manager 910 may also receive a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with the sounding reference signal resource set; determine a quasi-co-location assumption for the downlink reference signal resource; and measure the downlink reference signal resource based on the quasi-co-location assumption.

[0187] I / O controller 915 can manage input and output signals for device 905. I / O controller 915 can also manage peripheral devices that are not integrated into device 905. In some cases, I / O controller 915 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 915 can utilize a computer such as a Or another known operating system. In other cases, I / O controller 915 can represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 915 can be implemented as part of a processor. In some cases, a user can interact with device 905 via I / O controller 915 or via hardware components controlled by I / O controller 915.

[0188] The transceiver 920 may communicate bidirectionally via one or more antennas, wired links, or wireless links as described above. For example, the transceiver 920 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 920 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and demodulate packets received from the antenna.

[0189] In some cases, a wireless device may include a single antenna 925. However, in some cases, a device may have more than one antenna 925 that may be capable of simultaneously sending or receiving multiple wireless transmissions.

[0190] The memory 930 may include RAM and ROM. The memory 930 may store computer-readable, computer-executable code 935 including instructions that, when executed, cause the processor to perform various functions described herein. In some cases, the memory 930 may also contain, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0191] The processor 940 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 940 may be configured to operate a memory array using a memory controller. In other cases, the memory controller may be integrated into the processor 940. The processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 930) to cause the device 905 to perform various functions (e.g., functions or tasks that support beam switching techniques for uplink transmissions).

[0192] Based on configuring the downlink reference signal resources for UE 115 via the MAC CE, UE 115 may be able to quickly update the uplink beam to transmit on the SRS resource set. With the fast update of the uplink beam, the transceiver 920 can use a stronger beam for transmission. This can improve the uplink transmission quality of the uplink shared channel transmission, because the beam configuration of the uplink shared channel transmission is based on the transmission configuration of the SRS resource set. This can reduce the number of failed transmissions, which will result in battery waste of UE 115.

[0193] The code 935 may include instructions for implementing aspects of the present disclosure, including instructions for supporting wireless communications. The code 935 may be stored in a non-transitory computer-readable medium such as a system memory or other type of memory. In some cases, the code 935 may not be directly executed by the processor 940, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0194] Fig.10 A block diagram 1000 of a device 1005 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 1005 may be an example of aspects of a base station 105 as described herein. The device 1005 may include a receiver 1010, a communication manager 1015, and a transmitter 1020. The device 1005 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0195] The receiver 1010 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to beam switching techniques for uplink transmissions, etc.). The information may be passed to other components of the device 1005. The receiver 1010 may be a reference Fig.13 Examples of aspects of the transceiver 1320 are described. The receiver 1010 may utilize a single antenna or a collection of antennas.

[0196] The communication manager 1015 may send a sounding reference signal resource set configuration information to the UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; transmit downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and send the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption. The communication manager 1015 may also send a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with the sounding reference signal resource set; determine a quasi-co-location assumption of the downlink reference signal resource; and send the downlink reference signal resource based on the quasi-co-location assumption. The communication manager 1015 may be an example of aspects of the communication manager 1310 described herein.

[0197] The communication manager 1015 or its subcomponents may be implemented using hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented using code executed by a processor, the functions of the communication manager 1015 or its subcomponents may be performed by a general purpose processor, DSP, application specific integrated circuit (ASIC), FPGA or other programmable logic device designed to perform the functions described in this disclosure, discrete gate or transistor logic, discrete hardware components, or any combination thereof.

[0198] The communication manager 1015 or its subcomponents can be physically located in various locations, including being distributed so that portions of the functionality are implemented by one or more physical components at different physical locations. In some examples, the communication manager 1015 or its subcomponents can be separate and distinct components according to various aspects of the present disclosure. In some examples, the communication manager 1015 or its subcomponents can be combined with one or more other hardware components, including but not limited to input / output (I / O) components according to various aspects of the present disclosure, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof.

[0199] Transmitter 1020 can transmit signals generated by other components of device 1005. In some examples, transmitter 1020 can be co-located with receiver 1010 in a transceiver module. For example, transmitter 1020 can be a reference Fig.13 Examples of aspects of the transceiver 1320 are described. The transmitter 1020 may utilize a single antenna or a collection of antennas.

[0200] Fig.11 A block diagram 1100 of a device 1105 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 1105 may be an example of aspects of the device 1005 or base station 105 as described herein. The device 1105 may include a receiver 1110, a communication manager 1115, and a transmitter 1145. The device 1105 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0201] The receiver 1110 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to beam switching techniques for uplink transmissions, etc.). The information may be delivered to other components of the device 1105. The receiver 1110 may be a reference Fig.13 Examples of aspects of transceiver 1320 are described. Receiver 1110 may utilize a single antenna or a collection of antennas.

[0202] The communication manager 1115 may be an example of aspects of the communication manager 1015 as described herein. The communication manager 1115 may include an SRS resource set configuration component 1120, a DCI transmission component 1125, a QCL hypothesis determination component 1130, a reference signal resource transmission component 1135, and a MAC CE transmission component 1140. The communication manager 1115 may be an example of aspects of the communication manager 1310 described herein.

[0203] The SRS resource set configuration component 1120 may send a sounding reference signal resource set configuration information to the UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource. The DCI sending component 1125 may send downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered. The QCL hypothesis determination component 1130 may determine a quasi-co-location hypothesis of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource. The reference signal resource sending component 1135 may send an aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location hypothesis.

[0204] MAC CE transmitting component 1140 may transmit a MAC CE indicating downlink reference signal resources associated with a sounding reference signal resource set. QCL assumption determining component 1130 may determine a quasi co-location assumption for downlink reference signal resources. Reference signal resource transmitting component 1135 may transmit downlink reference signal resources based on the quasi co-location assumption.

[0205] Transmitter 1145 can transmit signals generated by other components of device 1105. In some examples, transmitter 1145 can be co-located with receiver 1110 in a transceiver module. For example, transmitter 1145 can be a reference Fig.13 Examples of aspects of the transceiver 1320 are described. The transmitter 1145 may utilize a single antenna or a collection of antennas.

[0206] Fig.12 A block diagram 1200 of a communication manager 1205 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The communication manager 1205 may be an example of aspects of the communication manager 1015, the communication manager 1115, or the communication manager 1310 described herein. The communication manager 1205 may include an SRS resource set configuration component 1210, a DCI transmission component 1215, a QCL hypothesis determination component 1220, a reference signal resource transmission component 1225, and a MAC CE transmission component 1230. Each of these modules may be in communication with each other directly or indirectly (e.g., via one or more buses).

[0207] The SRS resource set configuration component 1210 can transmit sounding reference signal resource set configuration information to the UE, the sounding reference signal resource set configuration information indicating a non-periodic sounding reference signal resource set, a non-periodic downlink reference signal resource associated with the non-periodic sounding reference signal resource set, and a time slot offset associated with the non-periodic downlink reference signal resource. In some examples, the SRS resource set configuration component 1210 can determine a scheduling offset for the non-periodic downlink reference signal resource based on the time slot offset, wherein the scheduling offset corresponds to the number of symbol periods between the last symbol period of the downlink control information and the first symbol period of the non-periodic downlink reference signal resource. In some cases, the non-periodic sounding reference signal resource set configuration information is sent in the radio resource control configuration. In some cases, the non-periodic downlink reference signal resource includes a channel state information reference signal resource.

[0208] The DCI transmission component 1215 may transmit downlink control information in the first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered. In some examples, the DCI transmission component 1215 may trigger the aperiodic downlink reference signal resource based on the sounding reference signal request field in the downlink control information. In some cases, the downlink control information includes group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

[0209] The QCL hypothesis determination component 1220 may determine a quasi-co-location hypothesis for the aperiodic downlink reference signal resource based on a time slot offset associated with the aperiodic downlink reference signal resource. In some examples, the QCL hypothesis determination component 1220 may determine a quasi-co-location hypothesis for the downlink reference signal resource. In some cases, the QCL hypothesis determination component 1220 may determine that the beam switching capability of the UE is less than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resource. In some examples, the QCL hypothesis determination component 1220 may identify a TCI state for the aperiodic downlink reference signal resource, wherein the quasi-co-location hypothesis is associated with the TCI state for the aperiodic downlink reference signal resource based on the beam switching capability of the UE being less than the scheduling offset.

[0210] In some cases, QCL hypothesis determining component 1220 can determine that the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resource. In some examples, QCL hypothesis determining component 1220 can identify a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein a quasi-co-location assumption is associated with the downlink signal based on the beam switching capability of the UE being greater than the scheduling offset. In some examples, QCL hypothesis determining component 1220 can identify a default quasi-co-location assumption, wherein the quasi-co-location assumption is the default quasi-co-location assumption based on the beam switching capability of the UE being greater than the scheduling offset.

[0211] In some examples, QCL hypothesis determining component 1220 can send a configuration of aperiodic downlink reference signal resources, the configuration including a TCI state associated with the aperiodic downlink reference signal resources. In some examples, QCL hypothesis determining component 1220 can indicate the TCI state of the downlink reference signal resources by a MAC CE, wherein the quasi co-location hypothesis is based on the TCI state of the downlink reference signal resources.

[0212] Reference signal resource sending component 1225 may send aperiodic downlink reference signal resources in a second time slot indicated by the first time slot based on a quasi co-location assumption.In some examples, reference signal resource sending component 1225 may send downlink reference signal resources based on a quasi co-location assumption.

[0213] The MAC CE sending component 1230 may send a MAC CE indicating a downlink reference signal resource associated with a sounding reference signal resource set. In some cases, the MAC CE includes a NZP CSI-RS identifier for the downlink reference signal resource, a sounding reference signal resource set identifier for the sounding reference signal resource set, a serving cell index, a bandwidth part identifier, or a combination thereof. In some cases, the MAC CE includes an indicator of an aperiodic resource trigger for the sounding reference signal resource set, a list of aperiodic resource triggers for the sounding reference signal resource set, a slot offset value for the sounding reference signal resource set, a slot offset for the downlink reference signal resource, or a combination thereof. In some cases, the sounding reference signal resource set is an aperiodic resource set, a periodic resource set, or a semi-persistent resource set.

[0214] Fig.13 A diagram of a system 1300 including a device 1305 supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The device 1305 may be an example of or include components of a device 1005, a device 1105, or a base station 105 as described herein. The device 1305 may include components for two-way voice and data communications including components for transmitting and receiving communications, including a communication manager 1310, a network communication manager 1315, a transceiver 1320, an antenna 1325, a memory 1330, a processor 1340, and an inter-station communication manager 1345. These components may be in electronic communication via one or more buses, such as a bus 1350.

[0215] The communication manager 1310 may send a sounding reference signal resource set configuration information to the UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; send downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determine a quasi-co-location assumption of the aperiodic downlink reference signal resource based on the time slot offset associated with the aperiodic downlink reference signal resource; and send the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based on the quasi-co-location assumption. The communication manager 1310 may also send a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with the sounding reference signal resource set; determine a quasi-co-location assumption of the downlink reference signal resource; and send the downlink reference signal resource based on the quasi-co-location assumption.

[0216] The network communications manager 1315 may manage communications with the core network (eg, via one or more wired backhaul links). For example, the network communications manager 1315 may manage the delivery of data communications for client devices such as one or more UEs 115.

[0217] The transceiver 1320 may communicate bidirectionally via one or more antennas, wired links, or wireless links as described above. For example, the transceiver 1320 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1320 may also include a modem to modulate packets and provide the modulated packets to the antenna for transmission, and demodulate packets received from the antenna.

[0218] In some cases, a wireless device may include a single antenna 1325. However, in some cases, a device may have more than one antenna 1325 that may be capable of simultaneously sending or receiving multiple wireless transmissions.

[0219] Memory 1330 may include RAM, ROM, or a combination thereof. Memory 1330 may store computer readable code 1335 including instructions that, when executed by a processor (e.g., processor 1340), cause the device to perform various functions described herein. In some cases, memory 1330 may also contain, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0220] Processor 1340 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, processor 1340 may be configured to operate a memory array using a memory controller. In some cases, the memory controller may be integrated into processor 1340. Processor 1340 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1330) to cause device 1305 to perform various functions (e.g., functions or tasks that support beam switching techniques for uplink transmissions).

[0221] The inter-site communication manager 1345 may manage communications with other base stations 105 and may include a controller or scheduler for controlling communications of UEs 115 in cooperation with other base stations 105. For example, the inter-site communication manager 1345 may coordinate scheduling of transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmissions. In some examples, the inter-site communication manager 1345 may provide an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between base stations 105.

[0222] The code 1335 may include instructions to implement aspects of the present disclosure, including instructions to support wireless communications. The code 1335 may be stored in a non-transitory computer-readable medium such as a system memory or other type of memory. In some cases, the code 1335 may not be directly executed by the processor 1340, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0223] Fig.14 A flow chart illustrating a method 1400 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The operations of the method 1400 may be implemented by a UE 115 or a component thereof as described herein. For example, the operations of the method 1400 may be implemented by a UE 115 or a component thereof as described herein. Figures 6 to 9 The communication manager described herein performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described below. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the functions described below.

[0224] At 1405, the UE may receive sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource. The operations of 1405 may be performed according to the methods described herein. In some examples, aspects of the operations of 1405 may be performed as described in reference to Figures 6 to 9 The described SRS resource set configuration component is performed.

[0225] At 1410, the UE may receive downlink control information in a first time slot, the downlink control information indicating that a non-periodic sounding reference signal resource set is triggered. The operation of 1410 may be performed according to the methods described herein. In some examples, aspects of the operation of 1410 may be as described in reference to Figures 6 to 9 The DCI receiving component described is performed.

[0226] At 1415, the UE may determine a quasi co-location hypothesis for the aperiodic downlink reference signal resource based on a slot offset associated with the aperiodic downlink reference signal resource. The operations of 1415 may be performed according to the methods described herein. In some examples, aspects of the operations of 1415 may be performed as described in reference to Figures 6 to 9 The described QCL assumes deterministic components.

[0227] At 1420, the UE may measure the aperiodic downlink reference signal resource in the second time slot indicated by the time slot offset based on the quasi co-location assumption. The operation of 1420 may be performed according to the methods described herein. In some examples, aspects of the operation of 1420 may be as described in reference to Figures 6 to 9 The described measurements were performed with the assembly.

[0228] Fig.15 A flow chart illustrating a method 1500 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by a UE 115 or a component thereof as described herein. For example, the operations of the method 1500 may be implemented by a UE 115 or a component thereof as described herein. Figures 6 to 9 The communication manager described herein performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described below. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the functions described below.

[0229] At 1505, the UE may receive sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource. The operations of 1505 may be performed according to the methods described herein. In some examples, aspects of the operations of 1505 may be performed as described in reference to Figures 6 to 9 The described SRS resource set configuration component is performed.

[0230] At 1510, the UE may receive downlink control information in a first time slot, the downlink control information indicating that a non-periodic sounding reference signal resource set is triggered. The operation of 1510 may be performed according to the methods described herein. In some examples, aspects of the operation of 1510 may be as described in reference to Figures 6 to 9 The DCI receiving component described is performed.

[0231] At 1515, the UE may determine that the beam switching capability of the UE is less than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resource. The operation of 1520 may be performed according to the methods described herein. In some examples, aspects of the operation of 1520 may be as described in reference to Figures 6 to 9 The described QCL assumes deterministic components.

[0232] At 1520, the UE may identify a TCI state for a non-periodic downlink reference signal resource, wherein a quasi-co-location assumption for the downlink reference signal resource is associated with the TCI state for the non-periodic downlink reference signal resource based on a beam switching capability less than a scheduling offset. The operation of 1525 may be performed according to the methods described herein. In some examples, aspects of the operation of 1525 may be performed as described in reference to Figures 6 to 9 The described QCL assumes deterministic components.

[0233] At 1525, the UE may measure the aperiodic downlink reference signal resource in the second time slot indicated by the time slot offset based on the quasi co-location assumption. The operation of 1530 may be performed according to the methods described herein. In some examples, aspects of the operation of 1530 may be as described in reference to Figures 6 to 9 The described measurements were performed with the assembly.

[0234] Fig.16 A flow chart illustrating a method 1600 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The operations of the method 1600 may be implemented by a base station 105 or components thereof as described herein. For example, the operations of the method 1600 may be implemented by a base station 105 or components thereof as described herein. Figures 10 to 13The communication manager described herein performs. In some examples, the base station may execute an instruction set to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform aspects of the functions described below.

[0235] At 1605, the base station may send a sounding reference signal resource set configuration information to the UE, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource. The operation of 1605 may be performed according to the methods described herein. In some examples, aspects of the operation of 1605 may be performed as described in reference to Figures 10 to 13 The described SRS resource set configuration component is performed.

[0236] At 1610, the base station may send downlink control information in the first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered. The operation of 1610 may be performed according to the methods described herein. In some examples, aspects of the operation of 1610 may be as described in reference to Figures 10 to 13 The described DCI sending component is performed.

[0237] At 1615, the base station may determine a quasi co-location hypothesis for the aperiodic downlink reference signal resource based on a time slot offset associated with the aperiodic downlink reference signal resource. The operations of 1615 may be performed according to the methods described herein. In some examples, aspects of the operations of 1615 may be performed as described in reference to Figures 10 to 13 The described QCL assumes deterministic components.

[0238] At 1620, the base station may send a non-periodic downlink reference signal resource in a second time slot indicated by the first time slot based on a quasi co-location assumption. The operation of 1620 may be performed according to the methods described herein. In some examples, aspects of the operation of 1620 may be as described in reference to Figures 10 to 13 The described reference signal resource sending component is performed.

[0239] Fig.17 A flow chart illustrating a method 1700 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The operations of the method 1700 may be implemented by a UE 115 or components thereof as described herein. For example, the operations of the method 1700 may be implemented by a UE 115 or components thereof as described herein. Figures 6 to 9The communication manager described herein performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described below. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the functions described below.

[0240] At 1705, the UE may receive a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with a sounding reference signal resource set. The operations of 1705 may be performed according to the methods described herein. In some examples, aspects of the operations of 1705 may be performed as described in reference to Figures 6 to 9 The MAC CE receiving component described is performed.

[0241] At 1710, the UE may determine a quasi co-location hypothesis for downlink reference signal resources. The operations of 1710 may be performed according to the methods described herein. In some examples, aspects of the operations of 1710 may be performed as described in reference to Figures 6 to 9 The described QCL assumes deterministic components.

[0242] At 1715, the UE may measure downlink reference signal resources based on the quasi co-location assumption. The operations of 1715 may be performed according to the methods described herein. In some examples, aspects of the operations of 1715 may be as described in reference to Figures 6 to 9 The described measurements were performed with the assembly.

[0243] Fig.18 A flow chart illustrating a method 1800 for supporting beam switching techniques for uplink transmissions according to aspects of the present disclosure is shown. The operations of the method 1800 may be implemented by a base station 105 or components thereof as described herein. For example, the operations of the method 1800 may be implemented by a base station 105 or components thereof as described herein. Figures 10 to 13 The communication manager described herein performs. In some examples, the base station may execute an instruction set to control the functional elements of the base station to perform the functions described below. Additionally or alternatively, the base station may use dedicated hardware to perform aspects of the functions described below.

[0244] At 1805, the base station may send a media access control (MAC) control element (CE) indicating a downlink reference signal resource associated with a sounding reference signal resource set. The operations of 1805 may be performed according to the methods described herein. In some examples, aspects of the operations of 1805 may be performed as described in reference to Figures 10 to 13 The MAC CE sending component described is performed.

[0245] At 1810, the base station may determine a quasi co-location hypothesis for downlink reference signal resources. The operations of 1810 may be performed according to the methods described herein. In some examples, aspects of the operations of 1810 may be performed as described in reference to Figures 10 to 13 The described QCL assumes deterministic components.

[0246] At 1815, the base station may send downlink reference signal resources based on the quasi co-location assumption. The operations of 1815 may be performed according to the methods described herein. In some examples, aspects of the operations of 1815 may be performed as described in reference to Figures 10 to 13 The described reference signal resource sending component is performed.

[0247] It should be noted that the methods described herein describe possible implementations, and that operations and steps may be rearranged or otherwise modified, and other implementations are possible. Additionally, aspects from two or more of the methods may be combined.

[0248] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes and LTE, LTE-A, LTE-A Pro, or NR technologies may be used in most of the description, the techniques described herein may be applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the techniques described may be 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.

[0249] The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0250] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or performed 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. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0251] The functions described herein can be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions can be stored on a computer-readable medium or sent via a computer-readable medium as one or more instructions or codes. Other examples and implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein can be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. Features that implement the functions can also be physically located at various locations, including being distributed so that parts of the functions are implemented at different physical locations.

[0252] Computer-readable media include non-transitory computer storage media and communication media, which 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-purpose computer or a special-purpose computer. As an example and not limitation, non-transitory computer-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, magnetic disk storage device or other magnetic storage device, or can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a general-purpose computer or a special-purpose computer or a general-purpose processor or a special-purpose processor. Any other non-transitory medium. Moreover, any connection is appropriately referred to as a computer-readable medium. For example, if a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology (such as infrared, radio and microwave) is used to send software from a website, server or other remote source, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology (such as infrared, radio and microwave) are all included in the definition of computer-readable media. Disk and disc as used herein include CD, laser disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0253] As used herein, including in the claims, "or" as used in a list of items (e.g., a list of items beginning with 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). Moreover, 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."

[0254] 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 label that distinguishes the similar components. If only the first reference number is used in the specification, the description applies to any of the similar components having the same first reference number, regardless of the second or other subsequent reference numbers.

[0255] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may 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." The detailed description includes specific details in order to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0256] 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 one 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 conforms to the broadest scope according to the principles and novel features disclosed herein.

Claims

1. A method for wireless communication at a user equipment UE, comprising: receiving sounding reference signal resource set configuration information, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; receiving downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; measuring the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based at least in part on the quasi co-location assumption; determining an uplink pre-decoder for the aperiodic sounding reference signal resource set based on the measurement; and Sending a sounding reference signal on an aperiodic sounding reference signal resource set based on the calculated uplink predecoder, wherein determining the quasi co-location hypothesis further comprises determining whether a beam switching capability of the UE is greater than a scheduling offset between downlink control information and the aperiodic downlink reference signal resource, and when the beam switching capability of the UE is greater than the scheduling offset: detecting a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

2. The method of claim 1 , wherein determining the quasi co-location hypothesis further comprises: determining that a beam switching capability of the UE is less than a scheduling offset between the downlink control information and the aperiodic downlink reference signal resource; as well as A transmission configuration indicator (TCI) state of the aperiodic downlink reference signal resource is identified, wherein the quasi co-location assumption is associated with the TCI state of the aperiodic downlink reference signal resource based at least in part on the beam switching capability being less than the scheduling offset. 3 . The method of claim 1 , wherein the default quasi co-location hypothesis is associated with a control resource set having a lowest control resource identifier among the control resource sets monitored in a latest time slot.

4. The method according to claim 1, further comprising: A configuration of the aperiodic downlink reference signal resource is received, the configuration comprising a transmission configuration indicator (TCI) state associated with the aperiodic downlink reference signal resource.

5. The method according to claim 1, further comprising: A scheduling offset for the aperiodic downlink reference signal resource is determined based at least in part on the slot offset, wherein the scheduling offset corresponds to a number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the aperiodic downlink reference signal resource.

6. The method according to claim 1, further comprising: Identify the configured transmission configuration indicator TCI state set; Determining that all configured TCI states in the set of configured TCI states are not associated with a spatial quasi-co-location hypothesis; as well as The time slot offset is determined to be zero, wherein the aperiodic downlink reference signal resource is located in the first time slot having the downlink control information.

7. The method according to claim 1, wherein the downlink control information comprises group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

8. The method of claim 1, wherein the aperiodic downlink reference signal resource is triggered based at least in part on a sounding reference signal request field in the downlink control information.

9. The method according to claim 1, wherein the aperiodic sounding reference signal resource set configuration information is received in a radio resource control configuration.

10. The method according to claim 1, wherein the aperiodic downlink reference signal resource comprises an aperiodic channel state information reference signal resource.

11. A method for wireless communication at a network entity, comprising: Sending sounding reference signal resource set configuration information, wherein the sounding reference signal resource set configuration information indicates an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; Sending downlink control information in a first time slot, wherein the downlink control information indicates that the aperiodic sounding reference signal resource set is triggered; determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; as well as transmitting the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based at least in part on the quasi co-location assumption; Based on the aperiodic downlink reference signal, a sounding reference signal is received on the aperiodic sounding reference signal resource set, wherein: Determining the quasi co-location hypothesis further includes determining whether a beam switching capability of the UE is greater than a scheduling offset between downlink control information and a non-periodic downlink reference signal resource, and when the beam switching capability of the UE is greater than the scheduling offset: identifying a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

12. The method of claim 11, wherein determining the quasi co-location hypothesis further comprises: Determining that a beam switching capability of a user equipment UE is less than a scheduling offset between the downlink control information and the aperiodic downlink reference signal resource; as well as A transmission configuration indicator (TCI) state of the aperiodic downlink reference signal resource is identified, wherein the quasi-co-location assumption is associated with the TCI state of the aperiodic downlink reference signal resource based at least in part on the beam switching capability of the UE being less than the scheduling offset.

13. The method of claim 11, wherein the default quasi co-location hypothesis is associated with a control resource set having a lowest control resource identifier among the control resource sets monitored in a most recent time slot.

14. The method according to claim 11, further comprising: The configuration of the aperiodic downlink reference signal resource is sent, wherein the configuration includes a transmission configuration indicator (TCI) state associated with the aperiodic downlink reference signal resource.

15. The method according to claim 11, further comprising: A scheduling offset for the aperiodic downlink reference signal resource is determined based at least in part on the slot offset, wherein the scheduling offset corresponds to a number of symbol periods between a last symbol period of the downlink control information and a first symbol period of the aperiodic downlink reference signal resource.

16. The method of claim 11, wherein the downlink control information comprises group-common downlink control information, uplink-based downlink control information, downlink-based downlink control information, or a combination thereof.

17. The method according to claim 11, further comprising: The aperiodic downlink reference signal resources are triggered based at least in part on a sounding reference signal request field in the downlink control information.

18. The method according to claim 11, wherein the aperiodic sounding reference signal resource set configuration information is sent in a radio resource control configuration.

19. The method of claim 11, wherein the aperiodic downlink reference signal resources comprise channel state information reference signal resources.

20. An apparatus for performing wireless communication at a user equipment UE, comprising: processor, a memory coupled to the processor; as well as Instructions, which are stored in the memory and can be executed by the processor to cause the device to perform the following operations: receiving sounding reference signal resource set configuration information, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; receiving downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; measuring the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based at least in part on the quasi co-location assumption; determining an uplink pre-decoder for the aperiodic sounding reference signal resource set based on the measurement; and sending a sounding reference signal on a non-periodic sounding reference signal resource set based on the calculated uplink pre-decoder, wherein to determine the quasi co-location hypothesis, the instructions are executed by the processor to further cause the apparatus to: determine whether the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources, and when the beam switching capability of the UE is greater than the scheduling offset: detecting a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

21. An apparatus for wireless communication at a network entity, comprising: processor, a memory coupled to the processor; as well as Instructions, which are stored in the memory and can be executed by the processor to cause the device to perform the following operations: Sending sounding reference signal resource set configuration information, wherein the sounding reference signal resource set configuration information indicates an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; Sending downlink control information in a first time slot, wherein the downlink control information indicates that the aperiodic sounding reference signal resource set is triggered; determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; transmitting the aperiodic downlink reference signal resource in a second time slot indicated by the first time slot based at least in part on the quasi co-location assumption; Based on the aperiodic downlink reference signal, a sounding reference signal is received on the aperiodic sounding reference signal resource set, wherein: To determine the quasi co-location hypothesis, the instructions are executed by the processor to further cause the apparatus to: determine whether the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resources, and when the beam switching capability of the UE is greater than the scheduling offset: identifying a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

22. An apparatus for performing wireless communication at a user equipment UE, comprising: means for receiving sounding reference signal resource set configuration information, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a slot offset associated with the aperiodic downlink reference signal resource; means for receiving downlink control information in a first time slot, the downlink control information indicating that the aperiodic sounding reference signal resource set is triggered; means for determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; means for measuring the aperiodic downlink reference signal resource in a second time slot indicated by the time slot offset based at least in part on the quasi co-location assumption; means for determining an uplink pre-decoder for said set of aperiodic sounding reference signal resources based on said measurements; and A means for sending a sounding reference signal on a non-periodic sounding reference signal resource set based on the calculated uplink pre-decoder, wherein the means for determining the quasi co-location hypothesis further comprises means for determining whether the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the non-periodic downlink reference signal resources, and when the beam switching capability of the UE is greater than the scheduling offset, means for: detecting a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

23. An apparatus for wireless communication at a network entity, comprising: A means for sending sounding reference signal resource set configuration information, the sounding reference signal resource set configuration information indicating an aperiodic sounding reference signal resource set, an aperiodic downlink reference signal resource associated with the aperiodic sounding reference signal resource set, and a time slot offset associated with the aperiodic downlink reference signal resource; A component for sending downlink control information in a first time slot, wherein the downlink control information indicates that the aperiodic sounding reference signal resource set is triggered; means for determining a quasi co-location hypothesis for the aperiodic downlink reference signal resource based at least in part on the slot offset associated with the aperiodic downlink reference signal resource; means for transmitting the aperiodic downlink reference signal resources in a second time slot indicated by the first time slot based at least in part on the quasi co-location assumption; means for receiving a sounding reference signal on the aperiodic sounding reference signal resource set based on the aperiodic downlink reference signal, wherein: The means for determining the quasi co-location hypothesis further includes means for determining whether the beam switching capability of the UE is greater than the scheduling offset between the downlink control information and the aperiodic downlink reference signal resources, and when the beam switching capability of the UE is greater than the scheduling offset, means for: identifying a downlink signal scheduled to overlap with the aperiodic downlink reference signal resource, wherein the quasi co-location hypothesis is associated with the downlink signal based at least in part on the beam switching capability being greater than the scheduling offset; or A default quasi-co-location hypothesis is identified, wherein the quasi-co-location hypothesis is based at least in part on the default quasi-co-location hypothesis that the beam switching capability is greater than the scheduling offset.

24. A non-transitory computer storage medium storing instructions which, when executed by a processor, cause the processor to perform the method of any one of claims 1-19.

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