WO2023279402A1

WO2023279402A1 - User equipment, base station, and wireless communication method for srs transmission

Info

Publication number: WO2023279402A1
Application number: PCT/CN2021/105614
Authority: WO
Inventors: Tian LI; Jia SHENG
Original assignee: Huizhou Tcl Cloud Internet Corporation Technology Co.Ltd
Priority date: 2021-07-09
Filing date: 2021-07-09
Publication date: 2023-01-12
Also published as: CN117643076A

Abstract

A user equipment (UE), a base station, and wireless communication methods for sounding reference signal (SRS) transmission are provided. The wireless communication method performed by the UE includes being configured, by the base station, with an SRS resource configuration and/or an SRS resource set configuration and applying, by the UE, an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission. This can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

Description

USER EQUIPMENT, BASE STATION, AND WIRELESS COMMUNICATION METHOD FOR SRS TRANSMISSION

BACKGROUND OF DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to the field of wireless communication systems, and more particularly, to a user equipment (UE) , a base station, and wireless communication methods for sounding reference signal (SRS) transmission. Further, the present disclosure relates to wireless communication systems operating in multiple input multiple output (MIMO) systems, and more specifically, an object of the present disclosure is to provide an improvement of spatial relation for SRS transmission. The present disclosure proposes some methods which are particularly interesting for enhancing a support of spatial relation for SRS transmission.

2. Description of the Related Art

Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These wireless communication systems may be capable of supporting 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 and fifth generation (5G) systems which may be referred to as new radio (NR) systems. A wireless multiple-access communications system may include a number of base stations or network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipments (UEs) . A wireless communication network may include a base station that can support communication for a UE. The UE may communicate with the base station via downlink (DL) and uplink (UL) . The DL refers to a communication link from the base station to the UE, and the UL refers to a communication link from the UE to the base station.

To exploit multiple path propagation, MIMO is a method for multiplying a capacity of a radio link using multiple transmissions and receiving antennas. By deploying multiple antennas at a transmitter and a receiver, MIMO refers to a practical technique for sending and receiving more than one data signal simultaneously over the same radio channel, which improves a performance of spectral efficiency greatly.

Multiple panels are implemented on a UE and one or multiple panel entities can be activated at a time, if one or multiple panel entities are used for transmitting a sounding reference signal (SRS) , an alignment of panel entity used for transmitting the SRS between a base station and the UE need to be determined.

Therefore, there is a need for a user equipment (UE) , a base station, and wireless communication methods, which can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

SUMMARY

An object of the present disclosure is to propose a user equipment (UE) , a base station, and a wireless communication method for sounding reference signal (SRS) transmission, which can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

In a first aspect of the present disclosure, a wireless communication method for SRS transmission performed by a UE comprises being configured, by a base station, with an SRS resource configuration and/or an SRS resource set configuration and applying, by the UE, an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission.

In a second aspect of the present disclosure, a wireless communication method for SRS transmission performed by a base station comprises configuring, to a UE, an SRS resource configuration and/or an SRS resource set configuration and controlling the UE to apply an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for SP SRS transmission, and/or a spatial relation for AP SRS transmission.

In a third aspect of the present disclosure, a UE comprises a memory, a transceiver, and a processor coupled to the memory and the transceiver. The processor is configured, by a base station, with an SRS resource configuration and/or an SRS resource set configuration. The processor is configured to apply an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission.

In a fourth aspect of the present disclosure, a base station comprises a memory, a transceiver, and a processor coupled to the memory and the transceiver. The processor is configured to configure, to a UE, an SRS resource configuration and/or an SRS resource set configuration and control the UE to apply an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for SP SRS transmission, and/or a spatial relation for AP SRS transmission.

In a fifth aspect of the present disclosure, a non-transitory machine-readable storage medium has stored thereon instructions that, when executed by a computer, cause the computer to perform the above method.

In a sixth aspect of the present disclosure, a chip includes a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the above method.

In a seventh aspect of the present disclosure, a computer readable storage medium, in which a computer program is stored, causes a computer to execute the above method.

In an eighth aspect of the present disclosure, a computer program product includes a computer program, and the computer program causes a computer to execute the above method.

In a ninth aspect of the present disclosure, a computer program causes a computer to execute the above method.

BRIEF DESCRIPTION OF DRAWINGS

In order to illustrate the embodiments of the present disclosure or related art more clearly, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures based on these figures without paying the premise.

FIG. 1 is a block diagram of one or more user equipments (UEs) and a base station (e.g., gNB) of communication in a communication network system based on an embodiment of the present disclosure.

FIG. 2 is a flowchart illustrating a wireless communication method for sounding reference signal (SRS) transmission performed by a UE based on an embodiment of the present disclosure.

FIG. 3 is a flowchart illustrating a wireless communication method for SRS transmission performed by a base station based on an embodiment of the present disclosure.

FIG. 4 is a schematic diagram illustrating an example of a multi-TRP/panel based SRS transmission based on an embodiment of the present disclosure.

FIG. 5 is a schematic diagram illustrating an example of a single-TRP/panel based SRS transmission based on an embodiment of the present disclosure.

FIG. 6 is a schematic diagram illustrating an example of applying a UL TCI based on a DCI application time only based on an embodiment of the present disclosure.

FIG. 7 is a schematic diagram illustrating an example of applying a UL TCI based on a MAC CE activation time only based on an embodiment of the present disclosure.

FIG. 8 is a schematic diagram illustrating an example of applying a UL TCI based on a larger value of a DCI application time based on an embodiment of the present disclosure.

FIG. 9 is a schematic diagram illustrating an example of applying a UL TCI based on a larger value of a MAC CE activation time based on an embodiment of the present disclosure.

FIG. 10 is a schematic diagram illustrating an example of applying a spatial relation based on the latest DCI based on an embodiment of the present disclosure.

FIG. 11 is a schematic diagram illustrating an example of applying a spatial relation based on a MAC CE based on an embodiment of the present disclosure.

FIG. 12 is a schematic diagram illustrating an example of applying a spatial relation based on the latest DCI based on an embodiment of the present disclosure.

FIG. 13 is a schematic diagram illustrating an example of applying a spatial relation based on the latest MAC CE based on an embodiment of the present disclosure.

FIG. 14 is a schematic diagram illustrating an example of a SP SRS activation/deactivation MAC CE based on an embodiment of the present disclosure.

FIG. 15 is a schematic diagram illustrating an example of a SP SRS activation/deactivation MAC CE based on an embodiment of the present disclosure.

FIG. 16 is a schematic diagram illustrating an example of applying a spatial relation after a MAC CE activation time based on an embodiment of the present disclosure.

FIG. 17 is a schematic diagram illustrating an example of applying a spatial relation without the MAC CE update command based on an embodiment of the present disclosure.

FIG. 18 is a block diagram of a system for wireless communication based on an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

For Rel-17 unified TCI framework, a TCI can be dynamically indicated by a DCI or MAC CE. Regarding a UL TCI state, the UL TCI provides a source reference for determining UL TX spatial filter UL channels, where the UL TCI can be a joint TCI state and separate UL TCI state. For a spatial relation of SP SRS in Rel-15/16, it is indicated by an SP SRS activation/deactivation MAC CE. Therefore, in order to follow the Rel-17 unified TCI framework, the spatial relation of SP need to be designed. In Rel-15/16, a spatial relation for an AP SRS resource can be updated by an enhanced SP/AP SRS spatial relation indication MAC CE. In Rel-17 unified TCI framework, the UL TCI can be dynamically changed by DCI or MAC CE. Therefore, to apply the relation from the UL TCI, an AP SRS triggering mechanism and spatial relation applying for AP SRS need to be designed.

In RAN1 #103-e meeting, regarding the fast uplink panel selection, five use cases are discussed, and the detailed agreement is shown as follows: In Rel-17 enhancement for facilitating fast uplink panel selection, the following use cases are assumed: 1. MPE mitigation. 2. UE power saving. 3. UL interference management. 4. Support different configurations across panels. 5. UL mTRP.

In RAN1 #103-e meeting, the UL TCI can be carried by DCI or MAC CE and the detailed agreement is shown as follows: On beam indication signaling medium to support joint or separate DL/UL beam indication in Rel. 17 unified TCI framework: Support L1-based beam indication using at least UE-specific (unicast) DCI to indicate joint or separate DL/UL beam indication from the active TCI states. The existing DCI formats 1_1 and 1_2 are reused for beam indication. Support a mechanism for UE to acknowledge successful decoding of beam indication. The ACK/NAK of the PDSCH scheduled by the DCI carrying the beam indication can be used as an ACK also for the DCI. FFS: Whether any additional specification support is needed. Support activation of one or more TCI states via MAC CE analogous to Rel. 15/16: At least for the single activated TCI state, the activated TCI state is applied. The content for the MAC CE is determined based on the outcome of issue 1. FFS: If supported, default TCI state when more than one TCI states are activated by MAC CE. Note: There is no implications on the support of single TRP or multi-TRP. FFS: Additional enhancement such as L1-based beam indication with group-common DCI. FFS: Whether the Rel. 17 beam indication can also apply to beam indication for single channel (e.g. PDSCH only, single CORESET) or a subset of channels. FFS: Additional details on extending the support of L1-based beam indication when separate UL (from DL) common beam indication is configured.

To solve the potential issues for spatial relation applying for SRS transmission, some embodiments of this disclosure propose the exemplary methods and provides a framework. An object of some embodiments of the present disclosure is to provide an improvement of spatial relation for SRS transmission. The present disclosure proposes some methods which are particularly interesting for enhancing a support of spatial relation for SRS transmission.

FIG. 1 illustrates that, in some embodiments, one or more user equipments (UEs) 10 and a base station (e.g., gNB) 20 for communication in a communication network system 30 based on an embodiment of the present disclosure are provided. The communication network system 30 includes the one or more UEs 10 and the base station 20. The one or more UEs 10 may include a memory 12, a transceiver 13, and a processor 11 coupled to the memory 12 and the transceiver 13. The base station 20 may include a memory 22, a transceiver 23, and a processor 21 coupled to the memory 22 and the transceiver 23. The

processor

11 or 21 may be configured to implement proposed functions, procedures and/or methods described in this description. Layers of radio interface protocol may be implemented in the

processor

11 or 21. The

memory

12 or 22 is operatively coupled with the

processor

11 or 21 and stores a variety of information to operate the

processor

11 or 21. The

transceiver

13 or 23 is operatively coupled with the

processor

11 or 21, and the

transceiver

13 or 23 transmits and/or receives a radio signal.

The

processor

11 or 21 may include application-specific integrated circuit (ASIC) , other chipset, logic circuit and/or data processing device. The

memory

12 or 22 may include read-only memory (ROM) , random access memory (RAM) , flash memory, memory card, storage medium and/or other storage device. The

transceiver

13 or 23 may include baseband circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules can be stored in the

memory

12 or 22 and executed by the

processor

11 or 21. The

memory

12 or 22 can be implemented within the

processor

11 or 21 or external to the

processor

11 or 21 in which case those can be communicatively coupled to the

processor

11 or 21 via various means as is known in the art.

In some embodiments, the processor 11 is configured, by the base station 20, with an SRS resource configuration and/or an SRS resource set configuration. The processor 11 is configured to apply an SRS transmission, wherein the UE 10 is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission. This can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

In some embodiments, the processor 21 is configured to configure, to the UE 10, an SRS resource configuration and/or an SRS resource set configuration and control the UE 10 to apply an SRS transmission, wherein the UE 10 is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for SP SRS transmission, and/or a spatial relation for AP SRS transmission. This can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

FIG. 2 illustrates a wireless communication method 200 for sounding reference signal (SRS) transmission performed by a UE based on an embodiment of the present disclosure. In some embodiments, the method 200 includes: a block 202, being configured, by a base station, with an SRS resource configuration and/or an SRS resource set configuration, and a block 204, applying, by the UE, an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission. This can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

FIG. 3 illustrates a wireless communication method 300 for SRS transmission performed by a base station based on an embodiment of the present disclosure. In some embodiments, the method 300 includes: a block 302, configuring, to a UE, an SRS resource configuration and/or an SRS resource set configuration, and a block 304, controlling the UE to apply an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for SP SRS transmission, and/or a spatial relation for AP SRS transmission. This can solve issues in the prior art, provide the association between the UE panel entity and the SRS resource, provide the spatial relation for SP SRS transmission, provide the spatial relation for AP SRS transmission, and/or provide a good communication performance.

FIG. 4 illustrates an example of a multi-TRP/panel based SRS transmission based on an embodiment of the present disclosure. FIG. 4 illustrates that, in some embodiments, for a UE operating in multi-TRP/panel transmission in NR, an SRS can be transmitted in different transmission occasions toward different TRPs, such that the UE has multiple chances to transmit the SRS. In addition, multiple SRS can be transmitted from multiple panels simultaneously toward multiple TRPs. For example, a first SRS and a second SRS can be transmitted from a first panel and a second panel respectively and simultaneously toward a first TRP and a second TRP. SRS transmission targeting towards different TRPs can avoid possible blockage between any TRP and the UE. As a result, SRS transmission towards multiple TRPs can not only enhance the reliability but also improve the coverage.

FIG. 5 illustrates an example of a single-TRP/panel based SRS transmission based on an embodiment of the present disclosure. FIG. 5 illustrates that, in some embodiments, for a UE operating in single-TRP/panel transmission in NR, an SRS can be transmitted from a panel toward a TRP. By this way, only one panel is activated, and ta transmitted power can be saved. In addition, it can simplify a detection in a gNB. For an SP SRS transmission in Rel-15/16, it is activated or deactivated by an SP SRS activation/deactivation MAC CE. Regarding an SP SRS MAC CE activation time, when the UE transmits a PUCCH with HARQ-ACK information in slot n corresponding to a PDSCH carrying a MAC CE activation command, a spatial relation for SP SRS transmission can be applied starting from the first slot that is after slot

where

is the number of slots per subframe and u is the SCS configuration for the PUCCH. For Table 1 and Table 2, since the duration for a frame is 10 ms and the number of slot for SP SRS MAC CE activation time is at least

it can be inferred that the MAC CE activation time is 3 ms.

Table 1: Number of OFDM symbols per slot, slots per frame, and slots per subframe for normal cyclic prefix

Table 2: Number of OFDM symbols per slot, slots per frame, and slots per subframe for extended cyclic prefix

Regarding an application time of a DCI based beam indication, it is agreed that the first slot that is at least X ms or Y symbols after the last symbol of an acknowledgment of a joint or separate UL beam indication, where the beam application time values (e.g., X/Y values) can be configured by the gNB based on UE capability. By this way, the application time guarantees that both gNB and UE can switch the beam after the acknowledgement is transmitted/received.

In some embodiments, an association between a UE panel entity and an SRS resource is provided. Since multiple panels are implemented on a UE and one or multiple panel entities can be activated at a time, if one or multiple panel entities are used for transmitting the SRS, the alignment of panel entity used for transmitting the SRS between gNB and UE can be determined. In some embodiments, several exemplary methods are proposed to define the association between UE panel entity and SRS resource.

In some embodiments, if a panel entity ID is included in the SRS resource configuration or SRS resource set configuration, the association between UE panel entity and SRS resource or SRS resource set can be explicitly determined. By this way, when UE is ready to transmit a given SRS resource, UE selects the panel for this SRS transmission based on the panel entity ID included in the SRS resource configuration or SRS resource set configuration. In details, the SRS resource configuration comprises a panel entity index (ID) , and the UE selects a corresponding panel entity associated with the panel entity ID for SRS transmission based on the panel entity ID. Therefore, it is straightforward to indicate the association between UE panel entity and SRS resource.

In some scenarios, e.g., single-TRP based transmission, only one SRS resource set is configured in the higher layer parameter. Since there may be multiple panels implemented on a UE, different SRS resources in the SRS resource set can be associated to different panels. In this case, a panel entity ID can be included in the SRS resource configuration (e.g., the higher layer parameter SRS-Resource or SRS-PosResource-r16) to indicate the association between UE panel entity and SRS resource. In details, the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, and the panel entity ID is included in the SRS resource configuration to indicate the association between the panel entity and the SRS resource. It is proposed that if only one SRS resource set is configured, a panel entity ID can be included in the SRS resource configuration (e.g., the higher layer parameter SRS-Resource or SRS-PosResource-r16) to indicate the association between UE panel entity and SRS resource. When UE is ready to transmit a given SRS resource, UE obtains the panel entity ID from the SRS resource configuration. With the panel entity ID, UE can select the panel for the corresponding SRS transmission. In some embodiments, the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, and the panel entity ID is included in the SRS resource configuration to indicate the association between the panel entity and the SRS resource.

In some embodiments, since there may be multiple SRS resource sets configured in the higher layer parameter, the association between UE panel entity and SRS resource can be designed per SRS resource set. For the multiple panels implemented on a UE, different SRS resource sets can be associated to different panels. In this case, a panel entity ID can be included in the SRS resource set configuration (e.g., the higher layer parameter SRS-ResourceSet or SRS-PosResourceSet-r16) to indicate the association between UE panel entity and SRS resource. In details, the SRS resource set configuration comprises a panel entity index (ID) , and the UE selects a corresponding panel entity associated with the panel entity ID for SRS transmission based on the panel entity ID. It is proposed that if multiple SRS resource sets are configured, a panel entity ID can be included in the SRS resource set configuration (e.g., the higher layer parameter SRS-ResourceSet or SRS-PosResourceSet-r16) to indicate the association between UE panel entity and SRS resource. When UE is ready to transmit the SRS resource of a given SRS resource set, UE obtains the panel entity ID from the SRS resource set configuration. With the panel entity ID, UE can select the panel for transmitting the SRS resource of the corresponding SRS resource set. In some embodiments, the SRS resource set configuration comprises SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, and the panel entity ID is included in the SRS resource set configuration to indicate the association between the panel entity and the SRS resource of the SRS resource set.

In some embodiments, since multiple SRS resources or SRS resource sets are configured, the association between UE panel entity and SRS resource can be fixed. By this way, when UE is ready to transmit a given SRS resource, the panel for this SRS transmission can be determined based on the pre-defined association between UE panel entity and SRS resource. Therefore, without the additional signaling of panel entity ID, the RRC overhead can be reduced. In some embodiments, the association between the panel entity and the SRS resource is pre-defined and/or fixed.

In some scenarios, e.g., single-TRP based transmission, only one SRS resource set is configured in the higher layer parameter. Since there are multiple SRS resources configured by higher layer parameter and multiple panels implemented on a UE, the mapping between UE panel entity and SRS resource that is identified by the higher layer parameter srs-ResourceId or srs-PosResourceId-r16 can be fixed. In details, it is proposed that if only one SRS resource set is configured, the mapping between UE panel entity and SRS resource can be fixed, where the mapping relationship can be pre-defined and aligned between gNB and UE. In detail, a first group of SRS resource is mapped to a first panel entity and a second group of SRS resource is mapped to a second panel entity and so on, where a group of SRS resource may include one or more SRS resources and the SRS resource is identified by the higher layer parameter srs-ResourceId or srs-PosResourceId-r16. For example, the SRS resource#0 and the SRS resource#1 are associated to panel entity#0, the SRS resource#2 are associated to panel entity#1, the SRS resource#3 are associated to panel entity#2. When UE is ready to transmit a given SRS resource, UE selects the panel entity based on the mapping between UE panel entity and SRS resource. With the selected panel entity, UE can perform SRS transmission. In some embodiments, the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, a mapping between the panel entity and the SRS resource is fixed, where the mapping between the panel entity and the SRS resource is pre-defined and aligned between the base station and the UE.

In some embodiments, since there may be multiple SRS resource sets configured in the higher layer parameter and multiple panels implemented on a UE, the mapping between UE panel entity and SRS resource set that is identified by the higher layer parameter srs-ResourceSetId or srs-PosResourceSetId-r16 can be fixed. It is proposed that if multiple SRS resource sets are configured, the mapping between UE panel entity and SRS resource set can be fixed, where the mapping relationship can be pre-defined and aligned between gNB and UE. In detail, a first group of SRS resource set is mapped to a first panel entity and a second group of SRS resource set is mapped to a second panel entity and so on, where a group of SRS resource set may include one or more SRS resource sets and the SRS resource set is identified by the higher layer parameter srs-ResourceSetId or srs-PosResourceSetId-r16. For example, the SRS resource set#0 is associated to panel entity#0, the SRS resource set#1 is associated to panel entity#1, the SRS resource set#2 is associated to panel entity#2. When UE is ready to transmit the SRS resource of a given SRS resource set, UE selects the panel entity based on the mapping between UE panel entity and SRS resource set. With the selected panel entity, UE can perform SRS transmission using this panel entity. In some embodiments, the SRS resource set configuration comprises SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, a mapping between the panel entity and the SRS resource set is fixed, where the mapping between the panel entity and the SRS resource set is pre-defined and aligned between the base station and the UE.

In Rel-15/16, when the resource type (e.g., higher layer parameter resourceType) in the SRS resource configuration (e.g., higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , the spatial relation is provided by reference signal included in the SP-SRS activation/deactivation MAC CE. For Rel-17 unified TCI framework, the TCI can be indicated by DCI or MAC CE. Regarding the UL TCI state, the UL TCI provides a source reference for determining UL TX spatial filter UL channels, where the UL TCI can be joint TCI state and separate UL TCI state. Therefore, the spatial relation of SP SRS can be designed based on Rel-17 unified TCI framework. Moreover, since the MAC CE activation time may not be equal to the application time of the DCI based beam indication, the spatial relation derived from the UL TCI can be applied to the SP SRS under different condition.

In some embodiments, the UE is configured to determine a first transmission occasion in which the UE applies the spatial relation for SP SRS transmission derived from an uplink (UL) transmission configuration indication (TCI) . In some embodiments, the UE determines the first transmission occasion based on a downlink control information (DCI) application time, a medium access control (MAC) control element (CE) activation time, or a larger value of the DCI application time and the MAC CE activation time.

In some embodiments, if UE transmits the SP SRS with the spatial relation from UL TCI starting from a first SP SRS transmission occasion that satisfies DCI application time requirement (e.g., X ms or Y symbols) and does not take into consideration of MAC CE activation time, it can simplify the process of applying the UL TCI for the SP SRS transmission. It is proposed when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , the first transmission occasion that applies the spatial relation derived from the UL TCI for SP SRS transmission is the first slot that is at least X ms or Y symbols after the last symbol of the acknowledgment of the PDCCH carrying the joint or separate UL beam indication, where the UL TCI is included in the DCI and the DCI in the PDCCH is used to schedule the PDSCH carrying the SP SRS activation MAC CE.

FIG. 6 illustrates an example of applying a UL TCI based on a DCI application time only based on an embodiment of the present disclosure. FIG. 6 illustrates that, in some embodiments, if the first SP SRS transmission occasion applying the spatial relation from UL TCI is determined only based on DCI application time requirement and does not take into consideration of MAC CE activation time, the first SP SRS transmission occasion is slot n+Tb and the last transmission occasion is slot n+Tc.

If UE transmits the SP SRS with the spatial relation from UL TCI starting from a first SP SRS transmission occasion that satisfies MAC CE activation time (e.g., 3 ms) and does not take into consideration of DCI application time requirement, the SP SRS activation command and the first transmission occasion applying the spatial relation from the UL TCI can be aligned. It is proposed when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , the first transmission occasion that applies the spatial relation derived from the UL TCI for SP SRS transmission is the first slot that is after slot

where the UL TCI is included in the DCI scheduling the SP SRS activation MAC CE, and

is the number of slots per subframe and u is the SCS configuration for the PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in slot n corresponding to the PDSCH carrying the MAC CE activation command.

FIG. 7 illustrates an example of applying a UL TCI based on a MAC CE activation time only based on an embodiment of the present disclosure. FIG. 7 illustrates that, in some embodiments, if the first SP SRS transmission occasion applying the spatial relation from UL TCI is determined only based on MAC CE activation time requirement and does not take into consideration of DCI application time, the first SP SRS transmission occasion is slot n+Tb and the last transmission occasion is slot n+Tc.

In some embodiments, if the first SP SRS transmission occasion applying the spatial relation from UL TCI is determined based on the larger value of DCI application time and MAC CE activation time, it can provide sufficient preparation time for UE and gNB. It is proposed when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , if the DCI application time (e.g. X ms or Y symbols) is not less than the MAC CE activation time (e.g. 3ms) , the first transmission occasion that applies the spatial relation derived from the UL TCI for SP SRS transmission is the first slot that is at least X ms or Y symbols after the last symbol of the acknowledgment of the PDCCH carrying the joint or separate UL beam indication, where the UL TCI is included in the DCI and the DCI in the PDCCH is used to schedule the PDSCH carrying the SP SRS activation MAC CE; while if the MAC CE activation time (e.g. 3ms) is larger than the DCI application time (e.g. X ms or Y symbols) , the first transmission occasion that applies the spatial relation derived from the UL TCI for SP SRS transmission is the first slot that is after slot

FIG. 8 illustrates an example of applying a UL TCI based on a larger value of a DCI application time based on an embodiment of the present disclosure. FIG. 9 illustrates an example of applying a UL TCI based on a larger value of a MAC CE activation time based on an embodiment of the present disclosure. FIG. 8 and FIG. 9 illustrate that, in some embodiments, as is shown in FIG. 8, the DCI application time is larger than the MAC CE activation time, and as is shown in FIG. 9, the MAC CE activation time is larger than the DCI application time. The first SP SRS transmission occasion applying the UL TCI is slot n+Tc and the last transmission occasion is slot n+Td.

In some embodiments, the first transmission occasion that applies the spatial relation derived from UL TCI is designed and the last transmission is determined based on the SP SRS deactivation command. The activation time starts from the first transmission occasion in which UE applies the spatial relation derived from the UL TCI for the SP SRS transmission to the last transmission occasion of SP SRS transmission. In Rel-15/16, the spatial relation for the active SP SRS resource remains the same during the activation time. In Rel-17 unified TCI framework, the UL TCI can be dynamically changed by DCI or MAC CE. Therefore, two methods can be designed for the spatial relation that applies for the SP SRS during the activation time. In some embodiments, during an activation time, UE transmits a SP SRS with a single spatial relation or a flexible spatial relation derived from the UL TCI indicated in a DCI or a MAC CE.

In some embodiments, if a single spatial relation is used for the active SP SRS resource during the activation time, the design is consistent with the existing principle. Since the UL TCI can be carried in DCI or MAC CE, the spatial relation for SP SRS during the activation time can be derived from the UL TCI in DCI or MAC CE. If the UL TCI is derived from the DCI that schedules the PDSCH carrying the activation MAC CE, it can simplify the design. On the other hand, if the UL TCI is derived from the latest DCI that satisfies the DCI application time, the spatial relation derived from UL TCI is the latest. It is proposed that when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , the spatial relation derived from the UL TCI for SP SRS transmission shall be applied starting from the first transmission occasion to the last transmission occasion, where the UL TCI is included in the DCI and the DCI is used to schedule the PDSCH carrying the activation MAC CE, or the UL TCI is derived from the latest DCI that satisfies the DCI application time. To be more specific, if the source RS in the UL TCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI is periodic SRS or SP SRS, the UE shall transmit the target SRS resource with the same spatial relation used for the transmission of the source RS. As is shown in FIG. 6, during the activation time of the SP SRS between the first transmission occasion and the last transmission occasion, UE transmit the SP SRS with spatial relation derived from the source RS of UL TCI in the DCI that is used to schedule the PDSCH carrying the SP SRS activation MAC CE.

FIG. 10 illustrates an example of applying a spatial relation based on the latest DCI based on an embodiment of the present disclosure. FIG. 10 illustrates that, in some embodiments, during the activation time of the SP SRS between the first transmission occasion and the last transmission occasion, UE transmit the SP SRS with spatial relation derived from the source RS of UL TCI in the latest DCI (e.g., DCI in slot n+Tb-K1) . For the case of multi-TRP/panel based SRS transmission shown in FIG. 4, since each link between a UE panel and a TRP corresponds to a separate channel, the spatial relation for SP SRS transmitted from different panels can be different. Therefore, for multi-TRP/panel based SRS transmission, it is proposed that the spatial relation for SP SRS transmitted from the first panel is derived from the source RS of the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the DCI and the spatial relation for SP SRS transmitted from the second panel is derived from the source RS of the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the DCI, where the DCI is used to schedule the PDSCH carrying the SP SRS activation MAC CE, or the DCI is the latest DCI that satisfies the DCI application time; besides, the spatial relation for SP SRS transmitted from the first panel and the spatial relation for SP SRS transmitted from the second panel shall be applied starting from the first transmission occasion to the last transmission occasion.

To be more specific, if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the DCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the transmission of the source RS. Moreover, if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the DCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the transmission of the source RS.

In some embodiments, if UL TCI is carried in MAC CE, UE transmits SP SRS with the spatial relation derived from the UL TCI in MAC CE. It is proposed that when the resource type (e.g., higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , the spatial relation derived from the UL TCI for SP SRS transmission shall be applied starting from the first transmission occasion to the last transmission occasion, where the UL TCI is carried in the MAC CE that satisfies the MAC CE activation time. To be more specific, if the source RS in the UL TCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI is periodic SRS or SP SRS, the UE shall transmit the target SRS resource with the same spatial relation used for the transmission of the source RS.

FIG. 11 illustrates an example of applying a spatial relation based on a MAC CE based on an embodiment of the present disclosure. FIG. 11 illustrates that, in some embodiments, during the activation time of the SP SRS between the first transmission occasion and the last transmission occasion, UE transmit the SP SRS with spatial relation derived from the source RS of UL TCI in the MAC CE. For the case of multi-TRP/panel based SRS transmission shown in FIG. 4, the spatial relation for SP SRS transmitted from different panels can be different. Therefore, for multi-TRP/panel based SRS transmission, it is proposed that the spatial relation for SP SRS transmitted from the first panel is derived from the source RS of the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the MAC CE and the spatial relation for SP SRS transmitted from the second panel is derived from the source RS of the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the MAC CE; besides, the spatial relation for SP SRS transmitted from the first panel and the spatial relation for SP SRS transmitted from the second panel shall be applied starting from the first transmission occasion to the last transmission occasion.

To be more specific, if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the transmission of the source RS. Moreover, if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the transmission of the source RS.

For Rel-17 unified TCI framework, since the TCI is indicated by DCI or MAC CE, the spatial relation for the SP SRS transmission can be dynamically changed and it can adapt to the channel. Therefore, during the activation time, UE can transmit SP SRS with the flexible spatial relation derived from the UL TCI. In some embodiments, it is proposed that when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to 'semi-persistent' , for each SP SRS transmission in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from the latest UL TCI for this SP SRS transmission shall be applied, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. Specially, for the SP SRS transmission in the first transmission occasion, the spatial relation that applies for this SP SRS transmission can derive from the UL TCI carried in the DCI scheduling the PDSCH carrying the activation MAC CE. To be more specific, if the source RS in the UL TCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI is periodic SRS or SP SRS, the UE shall transmit the target SRS resource with the same spatial relation used for the transmission of the source RS.

FIG. 12 illustrates an example of applying a spatial relation based on the latest DCI based on an embodiment of the present disclosure. FIG. 12 illustrates that, in some embodiments, during the activation time of the SP SRS between the first transmission occasion and the last transmission occasion, UE transmit the SP SRS with spatial relation derived from the source RS of UL TCI in the latest DCI. FIG. 13 illustrates an example of applying a spatial relation based on the latest MAC CE based on an embodiment of the present disclosure. FIG. 13 illustrates that, in some embodiments, during the activation time of the SP SRS between the first transmission occasion and the last transmission occasion, UE transmit the SP SRS with spatial relation derived from the source RS of UL TCI in the latest MAC CE.

In some embodiments, for the case of multi-TRP/panel based SRS transmission shown in FIG. 4, the spatial relation for SP SRS transmitted from different panels can be different. Therefore, for multi-TRP/panel based SRS transmission, it is proposed that for each SP SRS transmission from the first panel in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from the source RS of the UL TCI corresponding to the first panel (e.g. the first UL TCI) shall be applied, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time; besides, for each SP SRS transmission from the second panel in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel (e.g. the second UL TCI) shall be applied, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time.

To be more specific, if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the DCI or MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the transmission of the source RS. Moreover, if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the DCI or MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the transmission of the source RS.

In some embodiments, regarding the design on the SP SRS activation/deactivation MAC CE, since the spatial relation for the SP SRS transmission can be indicated by DCI or MAC CE, it does not have to carry the resource used for spatial relation derivation for SP SRS and it carries the SP SRS resource set index, which is to be activated or deactivated. For the case of multi-TRP/panel based SRS transmission shown in FIG. 4, a second SP SRS resource set index can be carried in the MAC CE to indicate the second SP SRS transmitted from the second panel.

In some embodiments, regarding the detailed design on the MAC CE, it has the following fields: 1. SRS Resource Set's Cell ID: This field indicates the identity of the Serving Cell, which contains the activated/deactivated SP SRS Resource Set. The length of the field is 5 bits. 2. SRS Resource Set's BWP ID: This field indicates a BWP as the codepoint of the DCI bandwidth part indicator field, which contains activated/deactivated SP SRS Resource Set. The length of the field is 2 bits. 3. SUL: This field indicates whether the MAC CE applies to the NUL carrier or SUL carrier configuration. This field is set to 1 to indicate that it applies to the SUL carrier configuration, and it is set to 0 to indicate that it applies to the NUL carrier configuration. 4. SP SRS Resource Set ID0: This field indicates the first SP SRS Resource Set ID identified by SRS-ResourceSetId, which is to be activated or deactivated. For the case of multi-TRP/panel based SRS transmission, this field indicates whether the SP SRS transmitted from the first panel is activated or deactivated. The length of the field is 4 bits. 5. SP SRS Resource Set ID1: For the case of multi-TRP/panel based SRS transmission, this field indicates the second SP SRS Resource Set ID identified by SRS-ResourceSetId, which indicates whether the SP SRS transmitted from the second panel is activated or deactivated. The length of the field is 4 bits. 6. A/D: This field indicates whether to activate or deactivate the corresponding SP SRS resource set. The field is set to 1 to indicate activation, otherwise it indicates deactivation. 7. R: Reserved bit, set to 0.

FIG. 14 illustrates an example of a SP SRS activation/deactivation MAC CE based on an embodiment of the present disclosure. FIG. 14 illustrates that, in some embodiments, if two fields of SP SRS Resource Set ID are always present, the MAC CE with a fixed size can provide a universal design for all the scenarios. FIG. 15 illustrates an example of a SP SRS activation/deactivation MAC CE based on an embodiment of the present disclosure. FIG. 15 illustrates that, in some embodiments, if the second field of SP SRS Resource Set ID is only present for the multi-TRP/panel based SRS transmission, the MAC CE with a variable size can reduce the MAC CE payload. In other word, for single panel based SRS transmission, only the first field of SP SRS Resource Set ID is present. To achieve this goal, it has an additional field: C: This field indicates whether the SP SRS Resource Set ID1 field are present. If this field is set to 1, the SP SRS Resource Set ID1 field is present, otherwise it is not present.

In some embodiments, applying, by the UE, the spatial relation for AP SRS transmission comprises triggering, by the UE, the AP SRS transmission in a multi-TRP/panel based SRS transmission by adding a field or enhancing the related higher layer parameter. In Rel-15/16, for single TRP/panel based SRS transmission, the AP SRS is triggered by the SRS request field in the DCI format 0_1/0_2/1_1/1_2/2_3. For the case of multi-TRP/panel based SRS transmission, the mechanism should be designed to trigger the AP SRS transmission from multiple panels. In some embodiments, two methods are proposed to trigger the AP SRS transmission in multi-TRP/panel based scenario.

In some embodiments, for multi-TRP/panel based SRS transmission, if a second SRS request field is added to trigger the AP SRS transmission from the second panel, the AP SRS from the two panels can be flexibly triggered. It is proposed that for multi-TRP/panel based SRS transmission, a second SRS request field with 2 bits is added in DCI (e.g. DCI format 0_1/0_2/1_1/1_2/2_3) to trigger the AP SRS transmission from the second panel. In detail, the first SRS request field is used to trigger the AP SRS transmission from the first panel, while the second SRS request field is used to trigger the AP SRS transmission from the second panel. Regarding the design on the second SRS request field, the mapping between the second SRS request field and the triggered AP SRS resource set (s) transmitted from the second panel can be shown in Table 3.

Table 3: The second SRS request field

In some embodiments, for multi-TRP/panel based SRS transmission, if the existing SRS request field is used and the higher layer parameter for AP SRS triggering is enhanced to support AP SRS triggering from multiple panels, it reduces the DCI overhead and can be easily extended to different numbers of panel. It is proposed that for multi-TRP/panel based SRS transmission, multiple groups of SRS resource set are configured in the SRS resource set list (e.g. higher layer parameter srs-ResourceSetToAddModList) and each group of SRS resource set corresponds to a value of SRS request field, where each SRS resource set in a group corresponds to a AP SRS transmitted from a UE panel, and the number of SRS resource set in a group is equal to the number of panel for AP SRS transmission, and the number of group is equal to the number of the valid state indicated by the SRS request field (e.g. 3) . For example, if the number of valid state is 3 and the number of panel for AP SRS transmission is 2, the mapping between SRS request field and triggered AP SRS resource set for each panel can be shown in the Table 4. For example, if the value of SRS request field is ‘10’ , the SRS resource set#2 for AP SRS transmitted from the first panel and SRS resource set#3 for AP SRS transmitted from the second panel are triggered.

Table 4: An mapping example between SRS request field and triggered AP SRS resource set

In Rel-15/16, the spatial relation for the AP SRS resource can be updated by enhanced SP/AP SRS spatial relation indication MAC CE. In Rel-17 unified TCI framework, the UL TCI can be dynamically changed by DCI or MAC CE. Therefore, to apply the relation from the UL TCI, two methods can be designed for updating the spatial relation that applies for AP SRS. In some embodiments, applying, by the UE, the spatial relation for AP SRS transmission comprises updating, by the UE, the spatial relation for AP SRS transmission based on a MAC CE update command or without the MAC CE update command.

In some embodiments, if the spatial relation derived from the UL TCI can be applied for the AP SRS transmission after the MAC CE activation time (e.g., 3 ms) , it is consistent with the existing principle. To derive the latest spatial relation, the UL TCI can be included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. It is proposed that when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g. higher layer parameter SRS-Resource or SRS-PosResource) is set to ‘aperiodic’ , the spatial relation derived from the UL TCI for AP SRS transmission shall be applied starting from the first slot that is after slot

where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time, and

is the number of slots per subframe and u is the SCS configuration for the PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in slot n corresponding to the PDSCH carrying the MAC CE update command. Specially, the UL TCI can be carried in the DCI triggering the AP SRS. To be more specific, if the source RS in the UL TCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI is periodic SRS or SP SRS, the UE shall transmit the target SRS resource with the same spatial relation used for the transmission of the source RS.

FIG. 16 illustrates an example of applying a spatial relation after a MAC CE activation time based on an embodiment of the present disclosure. FIG. 16 illustrates that, in some embodiments, after the MAC CE activation time, UE transmit the AP SRS in slot n+Tb with spatial relation derived from the source RS of UL TCI in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. For the case of multi-TRP/panel based SRS transmission shown in FIG. 4, the spatial relation for SP SRS transmitted from different panels can be different. Therefore, for multi-TRP/panel based SRS transmission, it is proposed that for the AP SRS transmission from the first panel, the spatial relation derived from the source RS of the UL TCI corresponding to the first panel (e.g. the first UL TCI) shall be applied starting from the first slot that is after slot

where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time; besides, for the AP SRS transmission from the second panel, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel (e.g. the second UL TCI) shall be applied starting from the first slot that is after slot

is the number of slots per subframe and u is the SCS configuration for the PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in slot n corresponding to the PDSCH carrying the MAC CE update command. Specially, the UL TCI can be carried in the DCI triggering the AP SRS.

To be more specific, if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) in the DCI or MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel (e.g. the first UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the first panel with the same spatial relation used for the transmission of the source RS. Moreover, if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) in the DCI or MAC CE is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel (e.g. the second UL TCI) is periodic SRS or SP SRS, the UE shall transmit the target SRS resource from the second panel with the same spatial relation used for the transmission of the source RS. Regarding the design on AP SRS spatial relation indication MAC CE, the MAC CE design in the above embodiments can be reused. In other words, the MAC CE designed in the above embodiments can be used to indicate the activation or deactivation of SP SRS and the spatial relation update of AP SRS. In addition, if the MAC CE is used to indicate the spatial relation update of AP SRS, the MAC entity shall ignore the A/D field.

In some embodiments, if the spatial relation derived from the UL TCI is applied for the AP SRS transmission without the MAC CE update command, it is a straightforward way and can simplify the process of updating spatial relation for AP SRS. To derive the latest spatial relation, the UL TCI can be included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. It is proposed that when the resource type (e.g. higher layer parameter resourceType) in the SRS resource configuration (e.g., higher layer parameter SRS-Resource or SRS-PosResource) is set to ‘aperiodic’ , the spatial relation derived from the UL TCI for AP SRS transmission shall be applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. Specially, the UL TCI can be carried in the DCI triggering the AP SRS. To be more specific, if the source RS in the UL TCI is SS/PBCH block or periodic CSI-RS or SP CSI-RS, the UE shall transmit the target SRS resource with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI is periodic SRS or SP SRS, the UE shall transmit the target SRS resource with the same spatial relation used for the transmission of the source RS.

FIG. 17 illustrates an example of applying a spatial relation without the MAC CE update command based on an embodiment of the present disclosure. FIG. 17 illustrates that, in some embodiments, a UE can transmit the AP SRS in slot n+Tb with spatial relation derived from the source RS of UL TCI in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. For the case of multi-TRP/panel based SRS transmission shown in FIG. 4, the spatial relation for SP SRS transmitted from different panels can be different. Therefore, for multi-TRP/panel based SRS transmission, it is proposed that for the AP SRS transmission from the first panel, the spatial relation derived from the source RS of the UL TCI corresponding to the first panel (e.g. the first UL TCI) shall be applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time; besides, for the AP SRS transmission from the second panel, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel (e.g. the second UL TCI) shall be applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time. Specially, the UL TCI can be carried in the DCI triggering the AP SRS.

In summary, the main idea of some embodiments of this disclosure are to provide a new design for SRS transmission, through which the transmitter is allowed to apply the SRS transmission. In some embodiments of this disclosure, several exemplary solutions are proposed to apply the SRS transmission, which include design on association between the UE panel entity and the SRS resource, the SP SRS transmission, and the AP SRS transmission. First of all, regarding the exemplary method of association, an explicit method and/or a fixed association method with one or multiple SRS resource sets are designed. Secondly, regarding the SP SRS transmission, determination on the first transmission occasion applying the UL TCI, the spatial relation applying for the SP SRS and the SP SRS activation/deactivation MAC CE are designed. Thirdly, regarding the AP SRS transmission, an AP SRS triggering mechanism and the spatial relation applying for the AP SRS are designed. Taking these exemplary methods into consideration, the support for SRS transmission is greatly enhanced.

The following table includes some abbreviations, which may be used in some embodiments of the present disclosure:

ACK	Acknowledgement
AP	Aperiodic

CSI-RS	Channel State Information Reference Signal
DCI	Downlink Control Information
gNB	Generation Node B
HARQ	Hybrid ARQ, Hybrid Automatic Repeat Request
ID	Index
MAC CE	MAC Control Element
NR	New Radio
NUL	Non-SUL
PUSCH	Physical Uplink Shared Channel
RAN	Radio Access Network
Rel	Release
RRC	Radio Resource Control
SCS	Sub-Carrier Spacing
SP	Semi-persistent
SRS	Sounding Reference Signal
SRI	SRS Resource Indicator
SS	Synchronization Signal
SUL	Supplementary Uplink
TCI	Transmission Configuration Indication
TRP	Transmission/Reception Point
TX	Transmission/Transmitter
UE	User Equipment
UL	Uplink

Commercial interests for some embodiments are as follows. 1. Solving issues in the prior art. 2. Providing the association between the UE panel entity and the SRS resource. 3. Providing the spatial relation for SP SRS transmission. 4. Providing the spatial relation for AP SRS transmission. 5. Providing a good communication performance. 6. Some embodiments of the present disclosure are used by 5G-NR chipset vendors, V2X communication system development vendors, automakers including cars, trains, trucks, buses, bicycles, moto-bikes, helmets, and etc., drones (unmanned aerial vehicles) , smartphone makers, communication devices for public safety use, AR/VR device maker for example gaming, conference/seminar, education purposes. Some embodiments of the present disclosure are a combination of “techniques/processes” that can be adopted in 3GPP specification to create an end product. Some embodiments of the present disclosure propose technical mechanisms.

FIG. 18 is a block diagram of an example system 700 for wireless communication based on an embodiment of the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. FIG. 18 illustrates the system 700 including a radio frequency (RF) circuitry 710, a baseband circuitry 720, an application circuitry 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled with each other at least as illustrated. The application circuitry 730 may include a circuitry such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combination of general-purpose processors and dedicated processors, such as graphics processors, application processors. The processors may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system.

While the present disclosure has been described in connection with what is considered the most practical and preferred embodiments, it is understood that the present disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

A wireless communication method for sounding reference signal (SRS) transmission performed by a user equipment (UE) , comprising:

being configured, by a base station, with an SRS resource configuration and/or an SRS resource set configuration; and

applying, by the UE, an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for semi-persistent (SP) SRS transmission, and/or a spatial relation for aperiodic (AP) SRS transmission.
The wireless communication method of claim 1, wherein the SRS resource configuration and/or the SRS resource set configuration comprises a panel entity index (ID) , and the UE selects a corresponding panel entity associated with the panel entity ID for SRS transmission based on the panel entity ID.
The wireless communication method of claim 2, wherein the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, and the panel entity ID is included in the SRS resource configuration to indicate the association between the panel entity and the SRS resource.
The wireless communication method of claim 2, wherein the SRS resource set configuration comprises SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, and the panel entity ID is included in the SRS resource set configuration to indicate the association between the panel entity and the SRS resource of the SRS resource set.
The wireless communication method of claim 1, wherein the association between the panel entity and the SRS resource is pre-defined and/or fixed.
The wireless communication method of claim 5, wherein the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, a mapping between the panel entity and the SRS resource is fixed, where the mapping between the panel entity and the SRS resource is pre-defined and aligned between the base station and the UE, and a first group of SRS resource is mapped to a first panel entity and a second group of SRS resource is mapped to a second panel entity.
The wireless communication method of claim 5, wherein the SRS resource set configuration comprises multiple SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, a mapping between the panel entity and the SRS resource set is fixed, where the mapping between the panel entity and the SRS resource set is pre-defined and aligned between the base station and the UE, and a first group of SRS resource set is mapped to a first panel entity and a second group of SRS resource set is mapped to a second panel entity.
The wireless communication method of claim 1, wherein the UE determines a first transmission occasion in which the UE applies the spatial relation for SP SRS transmission derived from an uplink (UL) transmission configuration indication (TCI) .
The wireless communication method of claim 8, wherein the UE determines the first transmission occasion based on a downlink control information (DCI) application time, a medium access control (MAC) control element (CE) activation time, or a larger value of the DCI application time and the MAC CE activation time.
The wireless communication method of claim 9, wherein if a resource type in the SRS resource configuration is set to SP and if the UE determines the first transmission occasion based on the DCI application time only, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is at least at least X ms or Y symbols after a last symbol of an acknowledgment of a physical downlink control channel (PDCCH) carrying a joint or separate UL beam indication, where the UL TCI is included in a DCI and the DCI in the PDCCH is used to schedule a physical downlink shared channel (PDSCH) carrying an SP SRS activation MAC CE.
The wireless communication method of claim 9, wherein if a resource type in the SRS resource configuration is set to SP and if the UE determines the first transmission occasion based on the MAC CE activation time only , the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is after

where the UL TCI is included in a DCI scheduling an SP SRS activation MAC CE, and
is a number of slots per subframe and u is a sub-carrier spacing (SCS) configuration for a PUCCH, and the UE transmits a PUCCH with hybrid automatic repeat request-acknowledge (HARQ-ACK) information in a slot n corresponding to a PDSCH carrying a MAC CE activation command.
The wireless communication method of claim 9, wherein and if a resource type in the SRS resource configuration is set to SP and if the UE determines the first transmission occasion based on the larger value of the DCI application time and the MAC CE activation time and the DCI application time is not less than the MAC CE activation time, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is at least at least X ms or Y symbols after a last symbol of an acknowledgment of a PDCCH carrying a joint or separate UL beam indication, where the UL TCI is included in a DCI and the DCI in the PDCCH is used to schedule a PDSCH carrying an SP SRS activation MAC CE; while if the MAC CE activation time is larger than the DCI application time, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is after

where the UL TCI is included in a DCI scheduling an SP SRS activation MAC CE, and
is a number of slots per subframe and u is a sub-carrier spacing (SCS) configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying a MAC CE activation command.
The wireless communication method of claim 8, wherein during an activation time, UE transmits a SP SRS with a single spatial relation or a flexible spatial relation derived from the UL TCI indicated in a DCI or a MAC CE.
The wireless communication method of claim 13, wherein the single spatial relation is used for the active SP SRS transmission during the activation time, and the single spatial relation is based on the UL TCI indicated in the DCI or the UL TCI indicated in the MAC CE.
The wireless communication method of claim 14, wherein if the resource type in the SRS resource configuration is set to SP, the spatial relation derived from the UL TCI for SP SRS transmission applies starting from the first transmission occasion to a last transmission occasion, where the UL TCI is included in the DCI and the DCI is used to schedule a PDSCH carrying an activation MAC CE, or the UL TCI is derived from a latest DCI that satisfies a DCI application time.
The wireless communication method of claim 15, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 14, wherein for multi-TRP/panel based SRS transmission, the spatial relation for SP SRS transmitted from a first panel entity is derived from a source RS of the UL TCI corresponding to the first panel entity in the DCI and the spatial relation for SP SRS transmitted from a second panel entity is derived from a source RS of the UL TCI corresponding to the second panel entity in the DCI, where the DCI is used to schedule the PDSCH carrying the SP SRS activation MAC CE, or the DCI is a latest DCI that satisfies the DCI application time; and the spatial relation for SP SRS transmitted from the first panel entity and the spatial relation for SP SRS transmitted from the second panel entity applies starting from the first transmission occasion to the last transmission occasion.
The wireless communication method of claim 17, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 18, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 14, wherein if the resource type in the SRS resource configuration is set to SP and if the UL TCI is carried in the MAC CE, the UE transmits the SP SRS with the spatial relation derived from the UL TCI in the MAC CE, the spatial relation derived from the UL TCI for SP SRS transmission applies starting from the first transmission occasion to a last transmission occasion, where the UL TCI is included in the MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 20, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 20, wherein for multi-TRP/panel based SRS transmission, the spatial relation for SP SRS transmitted from a first panel entity is derived from a source RS of the UL TCI corresponding to the first panel entity in the MAC CE and the spatial relation for SP SRS transmitted from a second panel entity is derived from a source RS of the UL TCI corresponding to the second panel entity in the MAC CE; and the spatial relation for SP SRS transmitted from the first panel entity and the spatial relation for SP SRS transmitted from the second panel entity applies starting from the first transmission occasion to the last transmission occasion.
The wireless communication method of claim 22, wherein if the source RS in the UL TCI corresponding to the first panel entity in the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 23, wherein if the source RS in the UL TCI corresponding to the second panel entity in the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 13, wherein in the flexible spatial relation, if the resource type in the SRS resource configuration is set to SP, for each SP SRS transmission in the activation time from the first transmission occasion to a last transmission occasion, the spatial relation derived from a latest UL TCI for SP SRS transmission is applied, where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 25, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 25, wherein for multi-TRP/panel based SRS transmission, for each SP SRS transmission from a first panel entity in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from a source RS of the UL TCI corresponding to the first panel entity is applied, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time; and for each SP SRS transmission from the second panel entity in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity is applied, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time.
The wireless communication method of claim 27, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 28, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 1, wherein a SP SRS activation/deactivation MAC CE carries a SP SRS resource set index, which is to be activated or deactivated, the SP SRS activation/deactivation MAC CE comprises the following fields: an SRS resource set’s cell ID, an SRS resource set’s bandwidth part (BWP) ID, a supplementary uplink (SUL) , a SP SRS resource set ID0, a SP SRS resource set ID1, an A/D, and an R.
The wireless communication method of claim 30, wherein the SP SRS activation/deactivation MAC CE comprises a fixed size or a variable size, if the SP SRS activation/deactivation MAC CE comprises the variable size, the SP SRS activation/deactivation MAC CE further comprises a C field.
The wireless communication method of claim 1, wherein applying, by the UE, the AP SRS transmission comprises triggering, by the UE, the AP SRS transmission in a multi-TRP/panel based SRS transmission by adding a field or enhancing the related higher layer parameter.
The wireless communication method of claim 32, wherein the UE is triggered by the base station for the AP SRS transmission in the multi-TRP/panel based SRS transmission by adding an SRS request field, a first SRS request field is used to trigger the AP SRS transmission from a first panel entity, a second SRS request field is added to trigger the AP SRS transmission from a second panel entity, and the mapping is between the second SRS request field and the triggered AP SRS resource set transmitted from the second panel entity based on a table.
The wireless communication method of claim 33, wherein for multi-TRP/panel based SRS transmission, multiple groups of SRS resource set are configured in an SRS resource set list and each group of SRS resource set corresponds to a value of an SRS request field, where each SRS resource set in a group corresponds to an AP SRS transmitted from the panel entity, and a number of SRS resource set in a group is equal to a number of the panel entity for AP SRS transmission, and a number of group is equal to a number of valid state indicated by the SRS request field.
The wireless communication method of claim 1, wherein applying, by the UE, the spatial relation for AP SRS transmission comprises updating, by the UE, the spatial relation for AP SRS transmission based on a MAC CE update command or without the MAC CE update command.
The wireless communication method of claim 35, wherein if a resource type in the SRS resource configuration is set to aperiodic and if the UE determines the spatial relation for AP SRS transmission based on the MAC CE update command, the spatial relation derived from the UL TCI for AP SRS transmission applies starting from a first slot that is after slot

where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time, and
is a number of slots per subframe and u is a SCS configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying the MAC CE update command.
The wireless communication method of claim 36, wherein the UL TCI is carried in the DCI triggering the AP SRS.
The wireless communication method of claim 36, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 36, wherein for multi-TRP/panel based SRS transmission, for the AP SRS transmission from a first panel entity, the spatial relation derived from a source RS of the UL TCI corresponding to the first panel entity applies starting from a first slot that is after slot
where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time; and for the AP SRS transmission from a second panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity applies starting from a first slot that is after slot
where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time, and
is a number of slots per subframe and u is a SCS configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying the MAC CE update command.
The wireless communication method of claim 39, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is periodic SRS or SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 40, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 35, wherein if a resource type in the SRS resource configuration is set to aperiodic and if the UE determines the spatial relation for AP SRS transmission without the MAC CE update command, the spatial relation derived from the UL TCI for AP SRS transmission is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 42, wherein the UL TCI is carried in the DCI triggering the AP SRS.
The wireless communication method of claim 42, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 42, wherein for multi-TRP/panel based SRS transmission, for the AP SRS transmission from a first panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the first panel entity is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time; and, for the AP SRS transmission from the second panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time.
The wireless communication method of claim 45, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is periodic SRS or SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 46, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
A wireless communication method for SRS transmission performed by performed by a base station, comprising:

configuring, to a UE, an SRS resource configuration and/or an SRS resource set configuration; and

controlling the UE to apply an SRS transmission, wherein the UE is equipped with one or more panel entities, and the SRS transmission comprises an association between the panel entity and an SRS resource, a spatial relation for SP SRS transmission, and/or a spatial relation for AP SRS transmission.
The wireless communication method of claim 48, wherein the SRS resource configuration and/or the SRS resource set configuration comprises a panel entity ID, and the base station controls the UE to select a corresponding panel entity associated with the panel entity ID for SRS transmission based on the panel entity ID.
The wireless communication method of claim 49, wherein the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, and the panel entity ID is included in the SRS resource configuration to indicate the association between the panel entity and the SRS resource.
The wireless communication method of claim 49, wherein the SRS resource set configuration comprises SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, and the panel entity ID is included in the SRS resource set configuration to indicate the association between the panel entity and the SRS resource of the SRS resource set.
The wireless communication method of claim 48, wherein the association between the panel entity and the SRS resource is pre-defined and/or fixed.
The wireless communication method of claim 52, wherein the SRS resource configuration comprises one SRS resource set, SRS resources in the SRS resource set are associated to the panel entities, a mapping between the panel entity and the SRS resource is fixed, where the mapping between the panel entity and the SRS resource is pre-defined and aligned between the base station and the UE, and a first group of SRS resource is mapped to a first panel entity and a second group of SRS resource is mapped to a second panel entity.
The wireless communication method of claim 52, wherein the SRS resource set configuration comprises multiple SRS resource sets, the SRS resource sets are associated to the panel entities, the association between the panel entity and the SRS resource is determined per SRS resource set, a mapping between the panel entity and the SRS resource set is fixed, where the mapping between the panel entity and the SRS resource set is pre-defined and aligned between the base station and the UE, and a first group of SRS resource set is mapped to a first panel entity and a second group of SRS resource set is mapped to a second panel entity.
The wireless communication method of claim 48, wherein the base station is configured to control the UE to determine a first transmission occasion in which the UE applies the spatial relation for SP SRS transmission derived from a UL TCI.
The wireless communication method of claim 55, wherein the base station controls the UE to determine the first transmission occasion based on a DCI application time, a MAC CE activation time, or a larger value of the DCI application time and the MAC CE activation time.
The wireless communication method of claim 56, wherein if a resource type in the SRS resource configuration is set to SP and if the base station controls the UE to determine the first transmission occasion based on the DCI application time only, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is at least at least X ms or Y symbols after a last symbol of an acknowledgment of a PDCCH carrying a joint or separate UL beam indication, where the UL TCI is included in a DCI and the DCI in the PDCCH is used to schedule a PDSCH carrying an SP SRS activation MAC CE.
The wireless communication method of claim 56, wherein if a resource type in the SRS resource configuration is set to SP and if the base station controls the UE to determine the first transmission occasion based on the MAC CE activation time only, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is after
where the UL TCI is included in a DCI scheduling an SP SRS activation MAC CE, and
is a number of slots per subframe and u is a SCS configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying a MAC CE activation command.
The wireless communication method of claim 56, wherein if a resource type in the SRS resource configuration is set to SP and if the base station controls the UE to determine the first transmission occasion based on the larger value of the DCI application time and the MAC CE activation time and the DCI application time is not less than the MAC CE activation time, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is at least at least X ms or Y symbols after a last symbol of an acknowledgment of a PDCCH carrying a joint or separate UL beam indication, where the UL TCI is included in a DCI and the DCI in the PDCCH is used to schedule a PDSCH carrying an SP SRS activation MAC CE; while if the MAC CE activation time is larger than the DCI application time, the first transmission occasion that applies the spatial relation for SP SRS transmission derived from the UL TCI is a first slot that is after
where the UL TCI is included in a DCI scheduling an SP SRS activation MAC CE, and
is a number of slots per subframe and u is a sub-carrier spacing (SCS) configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying a MAC CE activation command.
The wireless communication method of claim 55, wherein during an activation time, UE transmits a SP SRS with a single spatial relation or a flexible spatial relation derived from the UL TCI indicated in a DCI or a MAC CE.
The wireless communication method of claim 60, wherein the single spatial relation is used for the active SP SRS transmission during the activation time, and the single spatial relation is based on the UL TCI indicated in the DCI or the UL TCI indicated in the MAC CE.
The wireless communication method of claim 61, wherein if the resource type in the SRS resource configuration is set to SP, the spatial relation derived from the UL TCI for SP SRS transmission applies starting from the first transmission occasion to a last transmission occasion, where the UL TCI is included in the DCI and the DCI is used to schedule a PDSCH carrying an activation MAC CE, or the UL TCI is derived from a latest DCI that satisfies a DCI application time.
The wireless communication method of claim 62, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 61, wherein for multi-TRP/panel based SRS transmission, the spatial relation for SP SRS transmitted from a first panel entity is derived from a source RS of the UL TCI corresponding to the first panel entity in the DCI and the spatial relation for SP SRS transmitted from a second panel entity is derived from a source RS of the UL TCI corresponding to the second panel entity in the DCI, where the DCI is used to schedule the PDSCH carrying the SP SRS activation MAC CE, or the DCI is a latest DCI that satisfies the DCI application time; and the spatial relation for SP SRS transmitted from the first panel entity and the spatial relation for SP SRS transmitted from the second panel entity applies starting from the first transmission occasion to the last transmission occasion.
The wireless communication method of claim 64, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 65, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 61, wherein if the resource type in the SRS resource configuration is set to SP and if the UL TCI is carried in the MAC CE, the UE transmits the SP SRS with the spatial relation derived from the UL TCI in the MAC CE, the spatial relation derived from the UL TCI for SP SRS transmission applies starting from the first transmission occasion to a last transmission occasion, where the UL TCI is included in the MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 67, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 67, wherein for multi-TRP/panel based SRS transmission, the spatial relation for SP SRS transmitted from a first panel entity is derived from a source RS of the UL TCI corresponding to the first panel entity in the MAC CE and the spatial relation for SP SRS transmitted from a second panel entity is derived from a source RS of the UL TCI corresponding to the second panel entity in the MAC CE; and the spatial relation for SP SRS transmitted from the first panel entity and the spatial relation for SP SRS transmitted from the second panel entity applies starting from the first transmission occasion to the last transmission occasion.
The wireless communication method of claim 69, wherein if the source RS in the UL TCI corresponding to the first panel entity in the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 70, wherein if the source RS in the UL TCI corresponding to the second panel entity in the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 60, wherein in the flexible spatial relation, if the resource type in the SRS resource configuration is set to SP, for each SP SRS transmission in the activation time from the first transmission occasion to a last transmission occasion, the spatial relation derived from a latest UL TCI for SP SRS transmission is applied, where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 72, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 72, wherein for multi-TRP/panel based SRS transmission, for each SP SRS transmission from a first panel entity in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from a source RS of the UL TCI corresponding to the first panel entity is applied, where the UL TCI is included in the latest DCI that satisfies DCI application time or the latest MAC CE that satisfies MAC CE activation time; and for each SP SRS transmission from the second panel entity in the activation time from the first transmission occasion to the last transmission occasion, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity is applied, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time.
The wireless communication method of claim 74, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is a periodic SRS or an SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 75, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 76, wherein a SP SRS activation/deactivation MAC CE carries a SP SRS resource set index, which is to be activated or deactivated, , the SP SRS activation/deactivation MAC CE comprises the following fields: an SRS resource set's cell ID, an SRS resource set's BWP ID, a supplementary uplink (SUL) , a SP SRS resource set ID0, a SP SRS resource set ID1, an A/D, and an R.
The wireless communication method of claim 76, wherein the SP SRS activation/deactivation MAC CE comprises a fixed size or a variable size, if the SP SRS activation/deactivation MAC CE comprises the variable size, the SP SRS activation/deactivation MAC CE further comprises a C field.
The wireless communication method of claim 65, wherein applying, by the UE, the AP SRS transmission comprises triggering, by the UE, the AP SRS transmission in a multi-TRP/panel based SRS transmission by adding a field or enhancing the related higher layer parameter.
The wireless communication method of claim 79, wherein the base station triggers the UE for the AP SRS transmission in the multi-TRP/panel based SRS transmission by adding an SRS request field, a first SRS request field is used to trigger the AP SRS transmission from a first panel entity, a second SRS request field is added to trigger the AP SRS transmission from a second panel entity, and the mapping is between the second SRS request field and the triggered AP SRS resource set transmitted from the second panel entity based on a table.
The wireless communication method of claim 80, wherein for multi-TRP/panel based SRS transmission, multiple groups of SRS resource set are configured in an SRS resource set list and each group of SRS resource set corresponds to a value of an SRS request field, where each SRS resource set in a group corresponds to an AP SRS transmitted from the panel entity, and a number of SRS resource set in a group is equal to a number of the panel entity for AP SRS transmission, and a number of group is equal to a number of valid state indicated by the SRS request field.
The wireless communication method of claim 48, wherein applying, by the UE, the spatial relation for AP SRS transmission comprises updating, by the UE, the spatial relation for AP SRS transmission based on a MAC CE update command or without the MAC CE update command.
The wireless communication method of claim 82, wherein if a resource type in the SRS resource configuration is set to aperiodic and if the base station controls the UE to determine the spatial relation for AP SRS transmission based on the MAC CE update command, the spatial relation derived from the UL TCI for AP SRS transmission applies starting from a first slot that is after slot
where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time, and
is a number of slots per subframe and u is a SCS configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying the MAC CE update command.
The wireless communication method of claim 83, wherein the UL TCI is carried in the DCI triggering the AP SRS.
The wireless communication method of claim 83, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 83, wherein for multi-TRP/panel based SRS transmission, for the AP SRS transmission from a first panel entity, the spatial relation derived from a source RS of the UL TCI corresponding to the first panel entity applies starting from a first slot that is after slot
where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time; and for the AP SRS transmission from a second panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity applies starting from a first slot that is after slot
where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time, and
is a number of slots per subframe and u is a SCS configuration for a PUCCH, and the UE transmits a PUCCH with HARQ-ACK information in a slot n corresponding to a PDSCH carrying the MAC CE update command.
The wireless communication method of claim 86, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is periodic SRS or SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 87, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 82, wherein if a resource type in the SRS resource configuration is set to aperiodic and if the base station control the UE to update the spatial relation for AP SRS transmission without the MAC CE update command, the spatial relation derived from the UL TCI for AP SRS transmission is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in a latest DCI that satisfies a DCI application time or a latest MAC CE that satisfies a MAC CE activation time.
The wireless communication method of claim 89, wherein the UL TCI is carried in the DCI triggering the AP SRS.
The wireless communication method of claim 89, wherein if a source RS in the UL TCI is an SS/PBCH block, a periodic CSI-RS, or SP CSI-RS, the UE transmits a target SRS resource with the same spatial relation used for reception of the source RS; while if the source RS in the UL TCI is a periodic SRS or an SP SRS, the UE transmits the target SRS resource with the same spatial relation used for transmission of the source RS.
The wireless communication method of claim 90, wherein for multi-TRP/panel based SRS transmission, for the AP SRS transmission from a first panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the first panel entity is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time; and, for the AP SRS transmission from the second panel entity, the spatial relation derived from the source RS of the UL TCI corresponding to the second panel entity is applied after UE receives the DCI triggering AP SRS, where the UL TCI is included in the latest DCI that satisfies the DCI application time or the latest MAC CE that satisfies the MAC CE activation time.
The wireless communication method of claim 92, wherein if the source RS in the UL TCI corresponding to the first panel entity in the DCI or the MAC CE is an SS/PBCH block, a periodic CSI-RS, or an SP CSI-RS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the first panel entity is periodic SRS or SP SRS, the UE transmits the target SRS resource from the first panel entity with the same spatial relation used for the transmission of the source RS.
The wireless communication method of claim 93, wherein if the source RS in the UL TCI corresponding to the second panel entity in the DCI or the MAC CE is the SS/PBCH block, the periodic CSI-RS, or the SP CSI-RS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the reception of the source RS; while if the source RS in the UL TCI corresponding to the second panel entity is the periodic SRS or the SP SRS, the UE transmits the target SRS resource from the second panel entity with the same spatial relation used for the transmission of the source RS.
A user equipment (UE) , comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is configured to execute the method of any one of claims 1 to 47.
A base station, comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver;

wherein the processor is configured to execute the method of any one of claims 48 to 94.
A non-transitory machine-readable storage medium having stored thereon instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 94.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any one of claims 1 to 94.
A computer readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any one of claims 1 to 94.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any one of claims 1 to 94.
A computer program, wherein the computer program causes a computer to execute the method of any one of claims 1 to 94.