Systems and methods for sounding reference signals supporting beamforming

Abstract

A method for operating a user equipment (UE) includes: the UE receiving SRS configuration of a sounding reference signal (SRS) resource from a transmit-receive point (TRP); the UE determining at least one transmit beam for transmitting the SRS, wherein the at least one transmit beam is determined according to the TRP receive beam information and the SRS configuration; and the UE transmitting the SRS on the SRS resource using the at least one transmit beam according to the SRS configuration.

Description

[0001] This application claims priority to U.S. Non - Provisional Application No. 16 / 029,980, filed on Jul. 9, 2018, entitled "Systems and Methods for Sounding Reference Signals to Support Beamforming", which in turn claims priority to U.S. Provisional Patent Application No. 62 / 532,177, filed on Jul. 13, 2017, entitled "Systems and Methods for Sounding Reference Signals to Support Beamforming". The entire contents of both of these prior patent applications are incorporated herein by reference. Technical Field

[0002] The present invention generally relates to a system and method for wireless communication, and in particular embodiments, to a system and method for sounding reference signals to support beamforming. Background Art

[0003] Future wireless communication systems will operate at higher carrier frequencies in order to seek greater bandwidth and less interference. These wireless communication systems can operate at 6 GHz and higher frequencies. To fully utilize the greater bandwidth available in wireless communication systems, compared to the bandwidth and latency provided in existing fronthaul or backhaul connections, transmission - reception points (TRPs) may require more bandwidth and less latency. In addition, the density of TRPs may be much higher than current deployments, and the cost of laying wired high - capacity backhaul connections to all of these TRPs can be high. Additionally, in some cases, some TRPs may be transient or mobile in nature and may not support a wired connection.

[0004] Reference signals are typically used to assist communication devices in making measurements. For example, a TRP transmits a channel state information reference signal (CSI - RS) so that a user equipment (UE) can measure the downlink channel, while the UE transmits a sounding reference signal (SRS) so that the TRP can measure the uplink channel.

[0005] In communication systems with limited link budgets (such as communication systems operating above 6 GHz, such as millimeter wave (mmWave) communication systems), reference signals must be beamformed (on both the transmitting and receiving device sides) to meet the performance requirements in an operating environment with high path loss. Summary of the Invention

[0006] Exemplary embodiments provide a system and method for a sounding reference signal supporting beamforming.

[0007] According to an exemplary embodiment, a computer-implemented method for operating a user equipment (UE) is provided. The method includes: the UE receiving an SRS configuration of a sounding reference signal (SRS) resource from a transmit-receive point (TRP); the UE determining at least one transmit beam for transmitting the SRS, wherein the at least one transmit beam is determined according to the TRP receive beam information and the SRS configuration; and the UE transmitting the SRS on the SRS resource using the at least one transmit beam according to the SRS configuration.

[0008] Optionally, in any of the foregoing embodiments, the at least one transmit beam is further determined according to the downlink channel measurement performed by the UE.

[0009] Optionally, in any of the foregoing embodiments, the TRP receive beam information is received in the SRS configuration.

[0010] Optionally, in any of the foregoing embodiments, an embodiment further includes: the UE determining the TRP receive beam information according to the SRS configuration and the previously received TRP receive beam information.

[0011] Optionally, in any of the foregoing embodiments, an embodiment further includes: the UE determining the TRP receive beam information according to a continuation indicator and the previously received TRP receive beam information.

[0012] Optionally, in any of the foregoing embodiments, an embodiment further includes: the UE determining the TRP receive beam information according to a persistence indicator and the previously received TRP receive beam information.

[0013] Optionally, in any of the foregoing embodiments, for each SRS resource, the TRP receive beam information includes at least two message types.

[0014] Optionally, in any of the foregoing embodiments, the first message type represents information about a receive beam associated with an SRS resource at the TRP, and the second message type represents information about whether the receive beam has changed since the first message type.

[0015] Optionally, in any of the foregoing embodiments, the second message type represents information about whether the receive beam has changed relative to the first message type.

[0016] Optionally, in any of the foregoing embodiments, the second message type represents information about the duration window of the received beam.

[0017] Optionally, in any of the foregoing embodiments, the TRP received beam information includes an uplink reference signal resource indicator that was previously transmitted by the UE and received using a received beam associated with the SRS resource specified in the SRS configuration.

[0018] Optionally, in any of the foregoing embodiments, the TRP received beam information includes a downlink reference signal resource indicator that was previously transmitted by the UE and received with spatial filtering associated with the received beam, where the received beam is associated with the SRS resource specified in the SRS configuration.

[0019] Optionally, in any of the foregoing embodiments, the TRP received beam information includes an uplink data signal resource indicator that was previously transmitted by the UE and received using a received beam associated with the SRS resource specified in the SRS configuration.

[0020] According to an exemplary embodiment, a UE is provided. The UE includes: a non-transitory memory storing instructions; and one or more processors communicatively coupled to the memory. The one or more processors execute the instructions to: receive, from a TRP, an SRS configuration of an SRS resource; determine at least one transmit beam for transmitting the SRS, where the at least one transmit beam is determined based on TRP received beam information and the SRS configuration; and transmit the SRS on the SRS resource using the at least one transmit beam according to the SRS configuration.

[0021] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the at least one transmit beam based on downlink channel measurements performed by the UE.

[0022] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP received beam information based on the SRS configuration and previously received TRP received beam information.

[0023] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP received beam information based on a continuation indicator and previously received TRP received beam information.

[0024] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP receive beam information based on a persistence indicator and previously received TRP receive beam information.

[0025] Optionally, in any of the foregoing embodiments, the TRP receive beam information includes an uplink reference signal resource indicator that was previously transmitted by the UE and received using a receive beam associated with the SRS resource specified in the SRS configuration.

[0026] Optionally, in any of the foregoing embodiments, the TRP receive beam information includes a downlink reference signal resource indicator that was previously transmitted by the UE and received with spatial filtering associated with a receive beam that is associated with the SRS resource specified in the SRS configuration.

[0027] Optionally, in any of the foregoing embodiments, the TRP receive beam information includes an uplink data signal resource indicator that was previously transmitted by the UE and received using a receive beam associated with the SRS resource specified in the SRS configuration.

[0028] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: transmit the SRS using the at least one transmit beam according to the SRS configuration.

[0029] According to an exemplary embodiment, a non-transitory computer-readable medium storing computer instructions is provided. When the computer instructions are executed by one or more processors, the one or more processors are caused to perform the following steps: receive an SRS configuration of an SRS resource from a TRP; determine at least one transmit beam for transmitting the SRS, wherein the at least one transmit beam is determined based on TRP receive beam information and the SRS configuration; and transmit the SRS on the SRS resource using the at least one transmit beam according to the SRS configuration.

[0030] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the at least one transmit beam based on downlink channel measurements performed by the UE.

[0031] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP receive beam information based on the SRS configuration and previously received TRP receive beam information.

[0032] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP receive beam information based on a continuation indicator and previously received TRP receive beam information.

[0033] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: determine the TRP receive beam information based on a duration indicator and previously received TRP receive beam information.

[0034] Optionally, in any of the foregoing embodiments, the one or more processors further execute the instructions to: transmit the SRS using the at least one transmit beam according to the SRS configuration.

[0035] Implementing the above embodiments can reduce the overhead associated with transmitting reference signal configuration information. The reduction in overhead helps improve the overall performance of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To more fully understand the present invention and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0037] Figure 1 An exemplary wireless communication system according to an exemplary embodiment described herein is shown;

[0038] Figure 2 An exemplary communication system highlighting important communication beams according to an exemplary embodiment described herein is shown;

[0039] Figure 3 An exemplary communication system according to an exemplary embodiment described herein is shown, providing a technical summary disclosed in co-pending U.S. Patent Application No. 15 / 139,987;

[0040] Figure 4A An exemplary communication system highlighting a first scenario according to an exemplary embodiment described herein is shown, in which the TRP uses all available receive beams to receive the SRS;

[0041] Figure 4B An exemplary communication system highlighting a second scenario according to an exemplary embodiment described herein is shown, in which the TRP uses a portion of the available receive beams to receive the SRS;

[0042] Figure 5 A diagram highlighting the use of a continuation indicator to transmit receive beam information according to an exemplary embodiment described herein is shown;

[0043] Figure 6 A diagram highlighting the use of semi-static receive beam information according to an exemplary embodiment described herein is shown;

[0044] Figure 7 A flowchart illustrating exemplary operations that occur in transmitting receive beam information to a UE to assist a TRP in estimating the uplink and downlink channels between the TRP and the UE according to the exemplary embodiments described herein;

[0045] Figure 8A A flowchart illustrating exemplary operations that occur in a UE transmitting SRS according to the exemplary embodiments described herein;

[0046] Figure 8B A flowchart illustrating exemplary operations that occur in a UE transmitting SRS and highlighting the application of beam information application rules according to the exemplary embodiments described herein;

[0047] Figure 9 An exemplary communication system according to the exemplary embodiments described herein;

[0048] Figure 10A and Figure 10B An exemplary device according to the present invention that can implement various methods and teachings;

[0049] Figure 11 is a block diagram of a computing system that can be used to implement various devices and methods disclosed herein. Detailed Description

[0050] The structures, fabrications, and uses of various exemplary embodiments will be discussed in detail below. It should be understood that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed merely illustrate the specific structures and manners for implementing and using the embodiments, and do not limit the scope of the present invention.

[0051] Figure 1 An exemplary wireless communication system 100 is illustrated. The communication system 100 includes an access node 105 having a coverage area 107. The access node 105 serves a plurality of user equipments (UEs), including UE 110 and UE 112. As Figure 1As shown, access node 105 has established downlink connections (dashed lines) and uplink connections (dash-dotted lines) with multiple UEs. The downlink connections transfer data from access node 105 to the UEs, while the uplink connections transfer data from the UEs to access node 105. The data transferred through the downlink or uplink connections may include data transmitted between the UEs and a service (not shown) via the backhaul network 115. The wireless access may be provided in accordance with one or more wireless communication protocols, including Third Generation Partnership Project (3GPP) Long Term Evolution (LTE), LTE Advanced (LTE-A), Fifth Generation (5G) New Radio (NR), high speed packet access (HSPA), IEEE 802.11, etc. Although it should be understood that a communication system may employ multiple access nodes capable of communicating with multiple UEs, for simplicity, only one access node and two UEs are shown.

[0052] An access node may refer to an evolved NodeB (eNB), a base station, a next-generation (NG) NodeB (gNB), a NodeB, a master eNB (MeNB), a secondary eNB (SeNB), a master gNB (MgNB), a secondary gNB (SgNB), a remote radio head, an access point, while a UE may refer to a mobile device, a mobile station, a terminal, a subscriber, a user, etc. A transmission point (TP) may be considered as a transmission sending device, and a reception point (RP) may be considered as a transmission receiving device. A single device may be both a transmission point and a reception point for different transmissions; such a device is called a transmit-receive point (TRP). An access node may be a TRP. In some cases, a UE may also be a TRP.

[0053] In a 3GPP LTE communication system, a UE transmits sounding reference signals (SRS) to a TRP, enabling the TRP to estimate the complex channel response of the uplink channel. Then, by using the channel reciprocity relationship, an estimation result of the complex channel response of the downlink channel can be determined. The estimated channel response can be used to determine the communication beam at the TRP for transmitting downlink transmissions to the UE or receiving uplink transmissions from the UE. The term communication beam used in this document refers to a set of beamforming weights (such as the amplitude or phase shift of the antenna elements in an antenna array) for performing directional transmission or reception.

[0054] Different from the 3GPP LTE communication system, in order to achieve a commercially acceptable throughput level and range at higher carrier frequencies, typically both the TRP and the UE can perform beamforming in a millimeter wave (mmWave) communication system. Therefore, the SRS transmission scheme for the mmWave communication system may need to identify the communication beams that both the UE and the TRP will use to reduce the SRS probing overhead.

[0055] The beam can be a set of predefined beamforming weights in the context of codebook-based precoding or a set of dynamically defined beamforming (such as Eigen-based beamforming (EBB)) weights in the context of non-codebook-based precoding. It should be understood that the UE can rely on codebook-based precoding to transmit uplink signals and receive downlink signals, while the TRP can rely on non-codebook-based precoding to form certain radiation patterns to transmit downlink signals or receive uplink signals.

[0056] Simply probing in every possible transmission-reception communication beam combination will result in excessive SRS probing overhead, thus having a negative impact on communication performance and efficiency. According to the simple SRS probing technique, the UE performs SRS transmission according to different transmission beam directions in a set of transmission beam directions available to the UE, while the TRP receives various beamformed SRS transmissions from the UE according to different reception beam directions in a set of reception beam directions available to the TRP. The transmission beam is a communication beam used by a communication device such as the UE or the TRP to beamform a transmission and direct the transmission to the direction corresponding to these communication beams. The reception beam is a similar communication beam, but is used by the communication device to direct the receiver to the direction corresponding to these communication beams. The transmission beam and the reception beam are used to enhance the signal gain in their respective beam directions. The TRP estimates the complex channel response of the uplink channel based on the received SRS transmission and determines the estimation result of the corresponding downlink channel. These estimation results can be used to determine which communication beams the TRP uses to transmit downlink signals and which beam directions the UE uses to receive downlink signals.

[0057] It should be noted that the channels in the mmWave communication system are sparse in space, and only a few spatial directions are important. Due to the high path loss, the mmWave communication beam is easily blocked, and the reflected signal will generate high reflection loss (on the order of 10 dB to 25 dB), and additional path loss will occur when reaching the receiver. Therefore, in most cases, only the communication beam directly (or substantially directly) towards the device has a high enough signal-to-noise ratio (SNR) to support good throughput. However, there are cases where the communication beam directly towards the device is blocked. In these cases, the beam that is not directly but substantially directly towards the device may have the best SNR. The communication beam with a high enough SNR is called an important communication beam.

[0058] Figure 2 An exemplary communication system 200 highlighting the important communication beams is shown. The communication system 200 includes a TRP 205 that serves the UE 210. The TRP 205 can perform beamforming communication using a set of communication beams 215 ( Figure 2 showing a part of the set of communication beams 215). Similarly, the UE 210 communicates using a set of communication beams 220. Although there are many available communication beams in this set of communication beams 215 and this set of communication beams 220, due to the high path loss characteristic of the mmWave channel, only a part of the available communication beams are important. For example, only the TRP communication beams #T4 216, TRP communication beams #T5 217, and TRP communication beams #T6 218 that are directly or substantially directly towards the UE 210 are important receiving beams. At the same time, only the UE communication beams #U1 222, UE communication beams #U2 223, and UE communication beams #U5 221 that are directly or substantially directly towards the TRP 205 are important transmitting beams. Each combination of the transmit communication beam and the receive communication beam is called a transmit beam–receive beam combination (TRBC).

[0059] It should also be noted that even in important communication beams, only a part of the possible TRBCs in the important communication beams may be important. As an illustrative example, the combination of the UE communication beam #U1 222 and the TRP communication beam #T5 217 is important, and the combination of the UE communication beam #U2 223 and the TRP communication beam #T6 218 is equally important. However, the combination of the UE communication beam #U5 221 and the TRP communication beam #T6 218 may not be important because their directions do not match. Similarly, the combination of the UE communication beam #U2 223 and the TRP communication beam #T4 216 may also not be important.

[0060] To perform a complete downlink channel estimation for each link from the TRP to the UE, uplink SRS is used in a time-division duplexed (TDD) communication system, enabling the TRP to estimate the downlink channel based on the uplink channel using the channel reciprocity assumption. Then, the TRP can select to perform non-codebook-based single-user (SU) or multi-user (MU) multiple-input multiple-output (MIMO) beamforming for each UE. The uplink SRS can also be used to estimate the uplink channel to support uplink MIMO.

[0061] Since the UE uses beamformed SRS, it is very time-consuming (and resource-consuming) for each UE to transmit beamformed signals in each spatial direction and for the TRP to receive beamformed signals in each spatial direction. In the U.S. Patent Application No. 15 / 139,987, filed on April 27, 2016, with the invention title "Sounding Reference Signal (SRS) Design for Cellular Time Division Duplex (TDD) mmWave Systems", which is commonly assigned, a variety of techniques are provided that allow the UE to determine the most relevant uplink beam direction based on downlink measurement results, thereby reducing the SRS sounding overhead. This patent application is incorporated herein by reference.

[0062] Figure 3An exemplary communication system 300 is shown, providing a technical summary disclosed in the commonly assigned U.S. Patent Application No. 15 / 139,987. The communication system 300 includes a TRP 305 that serves a UE 310. The TRP 305 includes a plurality of radio frequency (RF) chains, where each RF chain communicates using a set of communication beams. For example, the first TRP RF chain communicates using a set of first communication beams 315, and the second TRP RF chain communicates using a set of second communication beams 317. Similarly, the UE 310 includes a plurality of RF chains, where each RF chain communicates using a set of communication beams. For example, the first UE RF chain communicates using a set of first communication beams 320, and the second UE RF chain communicates using a set of second communication beams 322. As disclosed in the commonly assigned U.S. Patent Application No. 15 / 139,987, the UE 310 determines which beam directions to select for transmitting beamformed SRS based on downlink measurement results and the SRS resources allocated to the UE 310. Reducing the TRBC also reduces the overhead associated with SRS sounding.

[0063] The commonly assigned U.S. Patent Application No. 15 / 139,987 also proposes a technique in which the TRP notifies the UE of which receive beam the TRP will use to listen to each SRS sounding opportunity. The receive beam information is an SRS configuration parameter, and the TRP notifying the UE of the receive beam information means that the TRP does not need to use all its available receive beams for each SRS sounding opportunity. For example, the TRP transmits a list including one or more beam indices corresponding to the receive beams that the TRP uses for listening during a particular SRS sounding opportunity. The list including one or more beam indices and other SRS configuration parameters, including identifiers of one or more SRS resources, time-domain behavior, number of ports, number of orthogonal frequency division multiplexed (OFDM) symbols, SRS bandwidth, hopping bandwidth, etc., or information thereof, is sent to the UE in the form of a media access control (MAC) control element (CE) message, a radio resource control (RRC) message, or a combination of a MAC CE message and an RRC message. Control information can also be sent in a downlink control information (DCI) message.

[0064] In one embodiment, the receiving beam information is implicitly indicated. For example, the type of the message is used to implicitly indicate the receiving beam information. The first message type of the message transmitted by the TRP can be used to represent the information about the receiving beam used by the TRP to receive the SRS transmission, while the second message type of the message can be used to represent the information about the change in the receiving beam. For example, there can be four available message types, and there is a one-to-one correspondence between the message types and one of the four receiving beams used by the TRP. After transmitting the information about the receiving beam to the UE, the message type can be used to represent the information about the change in the receiving beam. For another example, relative to the first message type, the second message type of the message can be used to represent the information about the change in the receiving beam used by the TRP. For yet another example, the second message type of the message can be used to represent the information about whether there is a continuous window for the receiving beam used by the TRP. The usage of the message type can be similar to the continuous indicator described below.

[0065] Figure 4A An exemplary communication system 400 highlighting the first scenario is shown, in which the TRP uses all available receiving beams to receive the SRS. The communication system 400 includes a TRP 405 serving a UE 410. As Figure 4A shown, the TRP 405 uses all available receiving beams, such as receiving beams R_1 415, R_2 417, and R_9 419, to receive the SRS. For example, the TRP405 has configured the UE 410 to transmit the SRS on two SRS resources. For the first SRS resource, the UE 410 uses the transmit beam U_1420 to transmit the SRS; for the second SRS resource, the UE 410 uses the transmit beam U_2 422 to transmit the SRS. It should be noted that since the TRP 405 is listening for these two SRS resources on all receiving beams, the order of detecting U-1 420 and U_2 422 is not important.

[0066] Figure 4B An exemplary communication system 450 highlighting the second scenario is shown, in which the TRP uses a part of the available receiving beams to receive the SRS. The communication system 450 includes a TRP 455 serving a UE 460. As Figure 4BAs shown, the TRP 455 uses the receiving beam R_3 465 for the first SRS resource and the receiving beam R_7 467 for the second SRS resource. For example, the TRP 455 has configured the UE 460 to transmit SRS on two SRS resources. For the first SRS resource, the UE 460 uses the transmitting beam U_1 470 to transmit SRS; for the second SRS resource, the UE 460 uses the transmitting beam U_2 472 to transmit SRS. Since the TRP455 does not use all receiving beams to monitor the SRS resources, the order of probing U_1 470 and U_2 472 may be important. If the sorting is incorrect, the receiving beams used by the TRP 455 to monitor the SRS resources may be suboptimal. Therefore, the UE460 may need to know which receiving beam the TRP 455 uses for each SRS resource and select the transmitting beam accordingly. It should be noted that different SRS resources may be used in different beam directions from the same UE port or for different UE ports. Although the TRP 455 is shown to use a single receiving beam to monitor the SRS resources at any given time, a suitable TRP may monitor the SRS resources on multiple receiving beams at any given time.

[0067] Document R1-1709376 titled "WF on SRS TX Beam Determination" published at the 89th meeting of 3GPP TSG-RAN WG1 in China in May 2017 discloses that there are two supported alternatives for performing SRS transmit beamforming for CSI acquisition and beam management, and the content of this document is incorporated herein by reference. In the first alternative, the UE uses TRP-transparent transmit beamforming for SRS (e.g., the UE determines the transmit beam for each SRS port or each SRS resource). In the second alternative, the TRP provides information to the UE (e.g., in the form of one or more information bits).

[0068] According to an exemplary embodiment, the TRP transmits information on one or more receive beams used for each allocated SRS resource. The TRP may use the SRS configuration of each SRS resource to send information on the receive beams. As an illustrative example, the TRP may transmit information on a downlink reference signal resource that has employed the same spatial filtering as the receive beam direction. An example of a technique is proposed in the 3GPP TSG-RAN WG1 special meeting document R1-1709936 titled "UL SRS Design for Beam Management and CSI Acquisition" published in June 2017, in which the TRP transmits a partial SRS configuration related to the TRP receive beam used by the TRP to the UE.

[0069] The UE receives information on the receive beams used for each allocated SRS resource and may be able to determine the associated transmit beam (or transmit beam direction) for each allocated SRS resource based on the measurement results of the transmitted downlink reference signal resources.

[0070] The overhead required to transmit information on the receive beams may be high in the following cases:

[0071] — When the TRP (i) receives using multiple receive beams for each SRS resource, (ii) receives using multiple sets of receive beams for each SRS resource, or (iii) receives using all receive beams for each SRS resource, the overhead associated with transmitting information on the downlink reference signal resources may be high.

[0072] — When the TRP configures multiple SRS resources for a UE and selects to use the same set of receive beams for each allocated SRS resource, repeatedly transmitting this same set of receive beams may unnecessarily consume resources.

[0073] According to an exemplary embodiment, receive beam information application rules are used to provide a basis for determining receive beam information. The receive beam information application rules allow the UE to determine receive beam information based on the current receive beam information, historical receive beam information, the existence of receive beam information, or a combination thereof, so that the UE can always use the receive beam information to determine the associated transmit beam (or transmit beam direction) for each allocated SRS resource.

[0074] Exemplary receive beam information application rules include:

[0075] (a) If no receive beam information (by SRS configuration or otherwise) is sent to or received by the UE, indicate to the UE that the TRP is listening to each SRS resource using all receive beams.

[0076] (b) If the receive beam information is sent to or received by the UE in the initial SRS configuration of a set of initial SRS resources (e.g., via downlink reference signal resources or other means), but the receive beam information for a set (multiple sets) of subsequent (time or frequency) SRS resources is not received in a subsequent SRS configuration, there are two possible ways to implicitly convey information (or rules that do not require transmission):

[0077] — The TRP uses the same receive beams for a set (multiple sets) of subsequent SRS resources as those used for the set of initial SRS resources. When the receive beams being used by the TRP are spatially quasi - co - located (QCL) with the receive beams used for the set of initial SRS resources, there is an alternative. Spatially quasi - co - located beams are discussed in detail in the co - assigned U.S. Provisional Patent Application No. 62 / 521,110, filed on June 16, 2017, entitled "System and Method for Communications Beam Recovery", the content of which is incorporated herein by reference.

[0078] — The TRP uses all receive beams for each SRS resource in the set of subsequent SRS resources.

[0079] Alternative exemplary receive beam application rules include:

[0080] (a') If no receive beam information is sent to or received by the UE (e.g., via SRS configuration or other means), the UE is indicated that the TRP is listening for each SRS resource using all receive beams.

[0081] (b') If the receive beam information is sent to or received by the UE in the initial SRS configuration of a set of initial SRS resources (e.g., via downlink reference signal resources or other means), but the receive beam information for a set (multiple sets) of subsequent (time or frequency) SRS resources is not received in a subsequent SRS configuration, there are two possible ways to implicitly convey information (or rules that do not require transmission):

[0082] — The TRP uses the same receive beams for a set (multiple sets) of subsequent SRS resources as those used for the set of initial SRS resources. When the receive beams being used by the TRP are spatially quasi - co - located (QCL) with the receive beams used for the set of initial SRS resources, there is an alternative.

[0083] — The TRP uses all receive beams for each SRS resource in the set of subsequent SRS resources.

[0084] If the received beam information includes a multi-bit continuation indicator (e.g., 2 bits or more, but other values are also possible), where the indicator indicates to the UE whether the received beam of the TRP is the same as (compared to the previously transmitted one) or has changed relative to the previous resource, then all received beams are used.

[0085] Examples of the multi-bit continuation indicator include:

[0086] — A first value (e.g., "00") indicates that the TRP is using the same received beam as the previously transmitted one. Alternatively, the TRP is using a received beam that is spatially quasi-co-located with the previously transmitted received beam.

[0087] — A second value (e.g., "01") indicates that the TRP is using a received beam corresponding to an increment of the downlink reference signal resource. Other bits can also be used to represent the increment; otherwise, the increment is 1 (for example). For example, the increment can be specified (e.g., binary '10' indicates an increment of 2), and the index of the increment can also be specified (e.g., binary '10' indicates that the increment is equal to the value corresponding to the third index).

[0088] — A third value (e.g., "10") indicates that the TRP is using a received beam corresponding to a decrement of the downlink reference signal resource. Other bits can also be used to represent the decrement; otherwise, the decrement is 1 (for example). For example, the decrement can be specified (e.g., binary '10' indicates a decrement of 2), and the index of the decrement can also be specified (e.g., binary '10' indicates that the decrement is equal to the value corresponding to the third index).

[0089] — A fourth value (e.g., "11") indicates that the TRP is using all received beams. Although a 2-bit continuation indicator is shown, other bit lengths are also possible.

[0090] Figure 5 Figure 500 is shown highlighting the use of the continuation indicator to send received beam information. As Figure 5As shown, at the first time, for the SRS resource I 505, the TRP uses the downlink reference signal resource to transmit the receive beam information, that is, the TRP sends the complete receive beam information in the SRS configuration. At a later time, for the SRS resource I+X 510, contrary to sending the complete receive beam information for the SRS resource I 505, the TRP sends a first continuation indicator in the SRS configuration. Similarly, at another time, for the SRS resource I+Y 515, the TRP sends another continuation indicator in the SRS configuration. Thus, at these times, the TRP can reduce the transmission overhead by only sending the continuation indicator. At yet another time, for the SRS resource Z 520, the TRP uses the downlink reference signal resource to transmit the receive beam information, that is, the TRP sends the complete receive beam information in the SRS configuration.

[0091] Other alternative exemplary receive beam application rules include:

[0092] (a”) If no receive beam information (by SRS configuration or otherwise) is sent to or received by the UE, then indicate to the UE that the TRP is listening to each SRS resource using all receive beams.

[0093] (b”) If receive beam information is sent to or received by the UE in the initial SRS configuration of a set of initial SRS resources (by downlink reference signal resource or otherwise), but no receive beam information for a set (multiple sets) of subsequent (time or frequency) SRS resources is received in the subsequent SRS configuration, then there are two possible ways to implicitly convey the information (or rules for not requiring transmission):

[0094] — The TRP uses the same receive beams for a set (multiple sets) of subsequent SRS resources as those used for the set of initial SRS resources. There is an alternative when the receive beams being used by the TRP are quasi-co-located (QCL) in space with the receive beams used for the set of initial SRS resources.

[0095] — The TRP uses all receive beams for each SRS resource in the set of subsequent SRS resources.

[0096] The receive beam information transmitted in the SRS resource is semi-static in nature. In other words, the receive beam information, the number of resources, and the number of SRS resources are valid for a certain period of time until a continuation indicator is received, and so on. The continuation indicator can be a bit string that is one or more bits long. For example, a first value indicates that the receive beam information, the number of resources, and the number of SRS resources are valid, and a second value indicates that the receive beam information, the number of resources, and the number of SRS resources are no longer valid. The period of time or the number of resources can be specified by a technical standard, by the operator of the communication system, by agreement between the TRP and the UE, or by indication from the TRP. The period of time or the number of resources can be indicated by the continuation indicator. The continuation indicator can be specified by a technical standard, by the operator of the communication system, by agreement between the TRP and the UE, or by indication from the TRP.

[0097] Figure 6 FIG. 600 illustrates highlighting the use of semi-static receive beam information. As Figure 6 shown, at a first time, for SRS resource I 605, the TRP transmits receive beam information using a downlink reference signal resource, that is, the TRP sends complete receive beam information in the SRS configuration. As shown in FIG. 600, the receive beam information is valid for three SRS resources. Therefore, at a second time (for SRS resource I+1 610) and a third time (for SRS resource I+2 615), the TRP does not need to send any form of receive beam information. At a fourth time, for SRS resource I+3 620, since the receive beam information transmitted for SRS resource I 605 is no longer valid, the TRP sends receive beam information. As Figure 6 shown, the TRP sends complete receive beam information. However, the TRP also sends a continuation indicator as previously discussed.

[0098] Although the discussion focuses on the receive beam information being valid for multiple SRS resources, the receive beam information may also be valid for a specified period of time until a continuation indicator is received, and so on. Therefore, discussing the validity based on the number of SRS resources should not be construed as limiting the scope or spirit of the exemplary embodiments.

[0099] According to an exemplary embodiment, a set of receive beams of the TRP is mapped to the same spatial direction as the transmitted downlink reference signal resource, thereby reducing the overhead generated by transmitting a set of receive beams for listening to SRS resources. In other words, when using a set of receive beams to listen to SRS resources, a single downlink reference signal resource can be used to transmit the set of receive beams. However, if the set of receive beams is different from the direction represented by a single downlink reference signal resource, other beam group indicators can be used, including:

[0100] —A set of receive beams that were originally only used for the previous uplink reference transmission (e.g., the previous SRS) can be sent to the UE as an uplink reference resource indicator. For example, the uplink reference resource indicator can be a bit string that is one or more bits long.

[0101] —A set of receive beams that were originally used for receiving the previous uplink data transmission can be sent to the UE as a demodulating reference signal (DMRS) indicator. For example, the DMRS indicator can be a bit string that is one or more bits long. Since there may be an uplink DMRS resource for each beam, there may be multiple indicators for each set of receive beams.

[0102] —A set of receive beams that were spatially filtered in the same way as in the previous downlink data transmission can be sent to the UE, for example, sent in the same way as a downlink DMRS indicator. Since there may be a downlink DMRS resource for each beam, there may be multiple indicators for each set of receive beams.

[0103] Figure 7 A flowchart of an exemplary operation 700 that occurs when a TRP sends receive beam information to a UE to assist the TRP in estimating the TRP of the downlink channel between the TRP and the UE is shown. Operation 700 can represent the operations that occur at the TRP when the TRP sends receive beam information to the UE to assist the TRP in estimating the TRP of the downlink channel between the TRP and the UE.

[0104] Operation 700 begins with the TRP configuring an SRS resource for the UE (step 705). The TRP optionally configures the receive beams used for each SRS resource, or configures a continuation indicator (step 707). The TRP sends the SRS configuration to the UE (step 709). The TRP optionally sends the TRP receive beam configuration or the continuation indicator (step 711). The TRP receives the SRS on the SRS resource using the configured receive beams (step 713). Based on the received SRS, the TRP estimates the uplink channel between the UE and the TRP (step 715). Based on the estimation result of the uplink channel, the TRP estimates the downlink channel between the TRP and the UE (step 717). For example, based on the estimation result of the uplink channel, the TRP uses channel reciprocity to estimate the downlink channel.

[0105] Figure 8A A flowchart of an exemplary operation 800 that occurs in a UE that sends an SRS is shown. Operation 800 can represent the operations that occur at the UE when the UE sends an SRS. Operation 800 can show a high-level view of the operations that occur at the UE when the UE sends an SRS.

[0106] Operation 800 begins with the UE receiving an SRS configuration (step 805). The UE determines the transmit beam for transmitting the SRS (step 807). The UE may determine the transmit beam based on the UE's downlink measurements, the TRP receive beam information received in the SRS configuration, the beam information application rule, or a combination thereof. Optionally, the UE may determine the transmit beam based on the UE's downlink measurements and whether there is TRP receive beam information in the SRS configuration. The UE transmits the SRS in the SRS resource using the transmit beam (step 809).

[0107] Figure 8B A flowchart of an exemplary operation 850 that occurs in a UE transmitting an SRS and highlights the application of the beam information application rule proposed herein is shown. Operation 850 may represent the operations that occur in the UE when the UE transmits an SRS. Operation 850 may show a detailed hierarchical diagram of the operations that occur at the UE when the UE transmits an SRS.

[0108] Operation 850 begins with the UE receiving an SRS configuration (step 855). The UE performs a check to determine whether TRP receive beam information is received using the SRS configuration (step 857). If the TRP receive beam information is received, the UE determines its transmit beam based on the TRP receive beam information (step 859), and then transmits the SRS using the transmit beam according to the SRS configuration (step 861).

[0109] If the TRP receive beam information is not received, the UE performs a check to determine whether the TRP receive beam information was received in the previous reception within the persistence window (step 863). The persistence window can be based on time, resources, specific start or end instructions, etc. The persistence window can be a value specified by a technical standard or by the operator of the communication system. Optionally, the persistence window is defined by one or more persistence indicators. If the TRP receive beam information is received within the persistence window, the UE uses the beam information application rule to determine the transmit beam (step 865). The UE optionally uses the information indicated by the continuation indicator (if received) to adjust the transmit beam (step 867). As an illustrative example, if the continuation indicator indicates that the TRP is using the same receive beam, the UE does not need to adjust the transmit beam. As another illustrative example, if the continuation indicator indicates that the TRP is using the receive beam corresponding to the downlink reference signal resource of the increment, the UE adjusts its transmit beam to the transmit beam corresponding to the TRP receive beam associated with the downlink reference signal resource of the increment. As another illustrative example, if the continuation indicator indicates that the TRP is using the receive beam corresponding to the downlink reference signal resource of the decrement, the UE adjusts its transmit beam to the transmit beam corresponding to the TRP receive beam associated with the downlink reference signal resource of the decrement. As yet another illustrative example, if the continuation indicator indicates that the TRP is using all receive beams, the UE adjusts its transmit beam to the transmit beam corresponding to all TRP receive beams, or to the transmit beam that is more important relative to the TRP receive beams. The UE uses the transmit beam to transmit the SRS according to the SRS configuration (step 861).

[0110] If the TRP receive beam information is not received within the persistence window, the UE determines the transmit beam based on the assumption that all receive beams of the TRP are used to monitor the SRS resource (step 869), and then uses the transmit beam to send the SRS according to the SRS configuration (step 861).

[0111] It should be noted that Figure 8B the operations shown are based on the exemplary beam information application rules proposed herein, and other exemplary beam information application rules will result in different operations or operations in a different order. Therefore, Figure 8B the operations shown should not be construed as limiting the scope or spirit of the exemplary embodiments.

[0112] Figure 9An exemplary communication system 900 is shown. Generally, system 900 enables multiple wireless or wired users to transmit and receive data and other content. System 900 may implement one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), or non-orthogonal multiple access (NOMA).

[0113] In this example, communication system 900 includes electronic devices (EDs) 910a to 910c, radio access networks (RANs) 920a and 920b, a core network 930, a public switched telephone network (PSTN) 940, the Internet 950, and other networks 960. Although Figure 9 certain quantities of these components or elements are shown, any quantity of these components or elements may be included in system 900.

[0114] The EDs 910a to 910c are configured to operate or communicate in system 900. For example, the EDs 910a to 910c are used to transmit or receive over wireless or wired communication channels. Each of the EDs 910a to 910c represents any suitable end-user device and may include devices such as (or may be referred to as): user equipment / device (UE), wireless transmit / receive unit (WTRU), mobile station, fixed or mobile subscriber unit, cellular phone, personal digital assistant (PDA), smartphone, laptop computer, computer, touchpad, wireless sensor, or consumer electronic device.

[0115] RANs 920a and 920b here respectively include base stations 970a and 970b. Each of base stations 970a and 970b is used to wirelessly connect to one or more of EDs 910a to 910c through an interface so as to be able to access core network 930, PSTN 940, Internet 950 or other network 960. For example, base stations 970a and 970b may include (or may be) one or more of several well-known devices, such as a base transceiver station (BTS), NodeB, evolved NodeB (eNodeB), home NodeB, home eNodeB, site controller, access point (AP) or wireless router. EDs 910a to 910c are used to connect to and communicate with Internet 950 through an interface and can access core network 930, PSTN 940 or other network 960.

[0116] In Figure 9 In the illustrated embodiment, base station 970a forms part of RAN 920a, and RAN 920a may include other base stations, elements or devices. Additionally, base station 970b forms part of RAN 920b, and RAN 920b may include other base stations, elements or devices. Base stations 970a and 970b respectively operate to transmit or receive wireless signals in a certain geographical area or range, which is sometimes referred to as a "cell". In some embodiments, multiple-input multiple-output (MIMO) technology may be employed such that each cell has multiple transceivers.

[0117] Base stations 970a and 970b communicate with one or more of EDs 910a to 910c using a wireless communication link through one or more air interfaces 990. The air interface 990 may use any suitable radio access technology.

[0118] It is expected that system 900 may use multi-channel access functions, including the solutions described above. In certain embodiments, the base stations and EDs implement LTE, LTE-A, LTE-B, LTE-C or 5G NR. Of course, other multiple access schemes and wireless protocols may also be employed.

[0119] RANs 920a and 920b communicate with the core network 930 to provide voice, data, applications, Voice over Internet Protocol (VoIP), or other services to EDs 910a through 910c. It is understood that RANs 920a and 920b or the core network 930 may communicate directly or indirectly with one or more other RANs (not shown). The core network 930 may also act as a gateway access to other networks such as the Public Switched Telephone Network (PSTN) 940, the Internet 950, and other networks 960. Additionally, some or all of the EDs 910a through 910c may include the functionality to communicate with different wireless networks over different wireless links using different wireless technologies or protocols. Instead of (or in addition to) wireless communication, the EDs may communicate with a service provider or switch (not shown) and the Internet 950 over a wired communication channel.

[0120] Although Figure 9 an example of a communication system is shown, various changes may be made to Figure 9 it. For example, the communication system 900 may include any number of EDs, base stations, networks, or any other appropriately configured components.

[0121] Figure 10A and Figure 10B illustrate exemplary devices in which the methods and teachings according to the present invention may be implemented. Specifically, Figure 10A an exemplary ED 1010 is shown, Figure 10B and an exemplary base station 1070 is shown. These components may be used in system 900 or any other appropriate system.

[0122] As Figure 10A shown, the ED 1010 includes at least one processing unit 1000. The processing unit 1000 performs various processing operations of the ED 1010. For example, the processing unit 1000 may perform signal encoding, data processing, power control, input / output processing, or any other function that enables the ED 1010 to operate in the system 900. The processing unit 1000 also supports the methods and teachings described in detail above. Each processing unit 1000 includes any appropriate processing or computing device for performing one or more operations. Each processing unit 1000 may include a microprocessor, a microcontroller, a digital signal processor, a field programmable gate array, or an application specific integrated circuit, among others.

[0123] ED 1010 also includes at least one transceiver 1002. The transceiver 1002 is used to modulate data or other content for transmission via at least one antenna or a Network Interface Controller (NIC) 1004. The transceiver 1002 is also used to demodulate data or other content received via at least one antenna 1004. Each transceiver 1002 includes any suitable structure for generating signals for wireless or wired transmission or for processing signals received wirelessly or wiredly. Each antenna 1004 includes any suitable structure for transmitting or receiving wireless or wired signals. One or more transceivers 1010 may be used in ED1002, and one or more antennas 1010 may be used in ED 1004. Although the transceiver 1002 is shown as a single functional unit, the transceiver 1002 may also be implemented using at least one transmitter and at least one separate receiver.

[0124] ED 1010 also includes one or more input / output devices 1006 or interfaces (such as a wired interface to the Internet 950). The input / output devices 1006 facilitate interaction (network communication) with users or other devices in the network. Each input / output device 1006 includes any suitable structure for providing information to the user or receiving or providing information from the user, such as a speaker, a microphone, a numeric keypad, a keyboard, a display, or a touch screen, including network interface communication.

[0125] In addition, ED 1010 includes at least one memory 1008. The memory 1008 stores instructions and data used, generated, or collected by ED 1010. For example, the memory 1008 may store software or firmware instructions executed by the processing unit 1000 and data for reducing or eliminating interference in the incoming signals. Each memory 1008 includes any suitable volatile or non-volatile storage and retrieval device. Any suitable type of memory may be used, such as random access memory (RAM), read only memory (ROM), a hard disk, an optical disk, a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, etc.

[0126] As Figure 10BAs shown, base station 1070 includes at least one processing unit 1050, at least one transceiver 1052 having the functions of a transmitter and a receiver, one or more antennas 1056, at least one memory 1058, and one or more input / output devices or interfaces 1066. A scheduler understood by those skilled in the art is coupled to the processing unit 1050. The scheduler may be included in the base station 1070 or may operate separately from the base station 1070. The processing unit 1050 performs various processing operations of the base station 1070, such as signal encoding, data processing, power control, input / output processing, or any other function. The processing unit 1050 may also support the methods and teachings described in detail above. Each processing unit 1050 includes any suitable processing or computing device for performing one or more operations. Each processing unit 1050 may include a microprocessor, a microcontroller, a digital signal processor, a field programmable gate array, or an application specific integrated circuit, etc.

[0127] Each transceiver 1052 includes any suitable structure for generating signals for wireless or wired transmission to one or more EDs or other devices. Each transceiver 1052 also includes any suitable structure for processing signals received from one or more EDs or other devices in a wireless or wired manner. Although the transmitter and receiver are shown combined into the transceiver 1052, they may also be separate components. Each antenna 1056 includes any suitable structure for transmitting or receiving wireless or wired signals. Although a common antenna 1056 is shown here coupled to the transceiver 1052, one or more antennas 1056 may be coupled to the transceiver 1052 such that when the transmitter and receiver are configured as separate components, the respective antennas 1056 may be coupled to the transmitter and the receiver. Each memory 1058 includes any suitable volatile or non-volatile storage and retrieval device. Each input / output device 1066 facilitates interaction (network communication) with users or other devices in the network. Each input / output device 1066 includes any suitable structure for providing information to the user or receiving or providing information from the user, and the information includes network interface communication.

[0128] Figure 11FIG. 1100 is a block diagram of a computing system 1100 that can be used to implement the devices and methods disclosed herein. For example, the computing system can be any entity in a UE, an access network (AN), mobility management (MM), session management (SM), a user plane gateway (UPGW), or an access stratum (AS). A particular device may utilize all of the shown components or only a subset of these components, and the degree of integration between devices may vary. Additionally, a device may include multiple instances of components, such as multiple processing units, processors, memories, transmitters, and receivers, etc. The computing system 1100 includes a processing unit 1102. The processing unit includes a central processing unit (CPU) 1114, a memory 1108, and may also include a mass storage device 1104, a video adapter 1110, and an I / O interface 1112 connected to a bus 1120.

[0129] The bus 1120 can be one or more of several types of bus architectures, including a memory bus or memory controller, a peripheral bus, or a video bus. The CPU 1114 can include any type of electronic data processor. The memory 1108 can include any type of non-transitory system memory, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), read-only memory (ROM), or a combination thereof. In one embodiment, the memory 1108 can include ROM used at boot time and DRAM that stores programs and data during program execution.

[0130] The mass storage 1104 can include any type of non-transitory storage device for storing data, programs, and other information and making these data, programs, and other information accessible via the bus 1120. For example, the mass storage 1104 can include one or more of a solid state disk, a hard disk drive, a disk drive, and an optical disk drive.

[0131] Video adapter 1110 and I / O interface 1112 provide interfaces to couple external input and output devices to processing unit 1102. As shown, examples of input and output devices include a display 1118 coupled to video adapter 1110 and a mouse / keyboard / printer 1116 coupled to I / O interface 1112. Other devices may be coupled to processor unit 1102, and additional or fewer interface cards may be used. For example, a serial interface such as Universal Serial Bus (USB) (not shown) may be used to provide an interface to external devices.

[0132] Processing unit 1102 also includes one or more network interfaces 1106, which may include, for example, a wired link such as an Ethernet cable, or a wireless link to an access node or different network. Network interface 1106 allows processing unit 1102 to communicate with remote units via a network. For example, network interface 1106 may provide wireless communication via one or more transmitters / transmitting antennas and one or more receivers / receiving antennas. In one embodiment, processing unit 1102 is coupled to a local area network 1122 or a wide area network for processing data and communicating with remote devices, which are, for example, other processing units, the Internet, or a remote storage facility.

[0133] It should be understood that one or more steps of the embodiment methods provided herein may be performed by corresponding units or modules. For example, a signal may be transmitted by a transmission unit or transmission module. A signal may be received by a receiving unit or receiving module. A signal may be processed by a processing unit or processing module. Other steps may be performed by a determination unit / module. Each unit / module may be hardware, software, or a combination thereof. For example, one or more of these units / modules may be integrated circuits, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC).

[0134] Although the invention has been described in detail with its advantages, it should be understood that various changes, substitutions, and alterations can be made to the invention without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A computer-implemented method for operating a user equipment (UE), characterized in that, The method includes: The UE receives SRS configuration of a sounding reference signal (SRS) resource from a transmit-receive point (TRP), where the SRS configuration includes the SRS resource and TRP beam information corresponding to the SRS resource, the type of the TRP beam information being a first message type or a second message type, the first message type indicating information about a beam associated with one of the SRS resources at the TRP, and the second message type indicating information about a change in the beam after the TRP beam information of the first message type; The UE determines at least one transmit beam for transmitting the SRS according to the TRP beam information; and The UE transmits the SRS on the SRS resource using the at least one transmit beam.

2. The method according to claim 1, characterized in that, The at least one transmit beam is further determined according to downlink channel measurement performed by the UE.

3. The method according to claim 1, characterized in that, It further includes: The UE determines the TRP beam information according to the SRS configuration and previously received TRP beam information.

4. The method according to claim 1, characterized in that, It further includes: The UE determines the TRP beam information according to a continuation indicator and previously received TRP beam information.

5. The method according to claim 1, characterized in that, It further includes: The UE determines the TRP beam information according to a persistence indicator and previously received TRP beam information.

6. The method according to claim 1, characterized in that, The second message type indicates information about a persistence window of the beam.

7. The method according to claim 1, characterized in that, The TRP beam information includes an uplink reference signal resource indicator that was previously transmitted by the UE and received using a beam associated with the SRS resource specified in the SRS configuration.

8. The method according to claim 1, characterized in that, The TRP beam information includes a downlink reference signal resource indicator that was previously transmitted by the UE and received with spatial filtering associated with a beam associated with the SRS resource specified in the SRS configuration.

9. The method according to claim 1, characterized in that, The TRP beam information includes an uplink data signal resource indicator that was previously transmitted by the UE and received using a beam associated with the SRS resource specified in the SRS configuration.

10. A user equipment (UE), characterized in that, It includes: A non-transitory memory storing instructions; And One or more processors communicating with the memory, where the one or more processors execute the instructions to: Receive a sounding reference signal (SRS) configuration for an SRS resource from a transmit-receive point (TRP), where the SRS configuration includes the SRS resource and TRP beam information corresponding to the SRS resource, and the type of the TRP beam information is a first message type or a second message type. The first message type represents information about a beam associated with one of the SRS resources at the TRP, and the second message type represents information about a change in the beam after the TRP beam information of the first message type. Determine at least one transmit beam for transmitting the SRS according to the TRP beam information; And Transmit the SRS on the SRS resource using the at least one transmit beam.

11. The UE according to claim 10, characterized in that, The one or more processors also execute the instructions to: determine the at least one transmit beam according to downlink channel measurements performed by the UE.

12. The UE according to claim 10, characterized in that, The one or more processors also execute the instructions to: determine the TRP beam information according to the SRS configuration and previously received TRP beam information.

13. The UE according to claim 10, characterized in that, The one or more processors also execute the instructions to: determine the TRP beam information according to a continuation indicator and previously received TRP beam information.

14. The UE according to claim 10, characterized in that,The one or more processors also execute the instructions to: determine the TRP beam information according to a persistence indicator and previously received TRP beam information.

15. The UE according to claim 10, wherein, The TRP beam information includes an uplink reference signal resource indicator that was previously transmitted by the UE and received using a beam associated with the SRS resource specified in the SRS configuration.

16. The UE according to claim 10, wherein, The TRP beam information includes a downlink reference signal resource indicator that was previously transmitted by the UE and received with spatial filtering associated with a beam associated with the SRS resource specified in the SRS configuration.

17. The UE according to claim 10, wherein, The TRP beam information includes an uplink data signal resource indicator that was previously transmitted by the UE and received using a beam associated with the SRS resource specified in the SRS configuration.

18. A non-transitory computer-readable medium storing computer instructions, wherein, When the computer instructions are executed by one or more processors, the one or more processors are caused to perform the following steps: Receive a sounding reference signal (SRS) configuration for an SRS resource from a transmit-receive point (TRP), where the SRS configuration includes the SRS resource and TRP beam information corresponding to the SRS resource, and the type of the TRP beam information is a first message type or a second message type. The first message type represents information about a beam associated with one of the SRS resources at the TRP, and the second message type represents information about a change in the beam after the TRP beam information of the first message type; Determine at least one transmit beam for transmitting the SRS according to the TRP beam information; And Transmit the SRS on the SRS resource using the at least one transmit beam.

19. The non-transitory computer-readable medium according to claim 18, wherein, The one or more processors also execute the instructions to: determine the at least one transmit beam according to downlink channel measurements performed by a user equipment (UE).

20. The non-transitory computer-readable medium according to claim 18, wherein, The one or more processors also execute the instructions to: determine the TRP beam information according to the SRS configuration and previously received TRP beam information.

21. The non-transitory computer-readable medium according to claim 18, wherein, The one or more processors also execute the instructions to: determine the TRP beam information according to a continuation indicator and previously received TRP beam information.

22. The non-transitory computer-readable medium according to claim 18, wherein, The one or more processors also execute the instructions to: determine the TRP beam information according to a persistence indicator and previously received TRP beam information.

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