GB2639929A

GB2639929A - Method, apparatus and computer program

Info

Publication number: GB2639929A
Application number: GB2404475.2A
Authority: GB
Inventors: Pekka Karjalainen Juha; Hakola Sami-Jukka; Koskela Timo
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2024-03-28
Filing date: 2024-03-28
Publication date: 2025-10-08
Also published as: WO2025201880A1; GB202404475D0

Abstract

There is provided user equipment comprising: means for receiving, from a network node, a configuration including a condition related to switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission, and means for performing at least one measurement on at least one reference signal. The apparatus also comprises: means for determining whether the condition has been fulfilled based on the measurement, and if so, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission. The first UL SRS resource set is associated with one antenna panel and the second UL SRS resource set is associated with one further antenna panel. The invention allows event-based antenna panel switching for simultaneous multi-panel (STxMP) PUSCH and PUCCH transmission in single-TRP and multi-TRP environments.

Description

METHOD, APPARATUS AND COMPUTER PROGRAM

Technical Field

Various examples of this disclosure relate to methods, apparatuses, and computer programs for a communication network.

Background

A communication network can be seen as a facility that enables communications between two or more communication devices, or provides communication devices access to a data network. A mobile or wireless communication network is one example of a communication network. A communication device may be provided with a service by an application server.

Such communication networks operate in accordance with standards such as those 15 provided by 3GPP (Third Generation Partnership Project) or ETSI (European Telecommunications Standards Institute). Examples of standards are the so-called 5G (5th Generation) standards provided by 3GPP.

Summary

Some examples of this disclosure will be described with respect to certain aspects.

These aspects are not intended to indicate key or essential features of the embodiments of this disclosure, nor are they intended to be used to limit the scope thereof. Other features, aspects, and elements will be readily apparent to a person skilled in the art in view of this disclosure. For example, it should be appreciated that further aspects may be provided by the combination of any two or more of the various aspects described below.

According to an aspect, there is provided an apparatus comprising: means for receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission; means for performing at least one measurement on at least one reference signal; means for determining whether the condition has been fulfilled based on the at least one measurement; and means for, based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first uplink, UL, sounding reference signal, SRS, resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.

In some examples, the at least one first UL SRS resource set is associated with at least one antenna panel of the apparatus, and wherein the at least one second UL SRS resource set is associated with at least one further antenna panel of the apparatus.

In some examples, the apparatus comprises: means for providing, to the network node, a capability indication of a capability for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the capability is indicated either as relevant to physical uplink shared channel, PUSCH, or physical uplink control channel, PUCCH, or as a capability for 15 both PUSCH and PUCCH.

In some examples, the apparatus comprises: means for receiving, from the network node, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.

In some examples, the apparatus comprises: means for performing the uplink 20 transmission to the network node based on the at least one second UL SRS resource set.

In some examples, the apparatus comprises: means for performing the uplink transmission to the network node based on the at least one second UL SRS resource set, wherein the uplink transmission being performed is a simultaneous multi-panel transmission.

In some examples, the means for performing at least one measurement on at least one reference signal comprises: means for performing the at least one measurement on at least one downlink reference signal resource; and means for comparing the at least one measurement to at least one previous measurement, wherein the at least one previous measurement is associated with measurements performed previously on downlink reference signal resources.

In some examples, the at least one reference signal comprises: a non-zero power channel state information reference signal, and a synchronisation signal block.

In some examples, the condition is associated with an event, wherein the request being provided to the network node is associated with the event being triggered.

In some examples, the condition comprises: measured values related to power of a first set of reference signals being a threshold value greater than measured values related to power of a second set of reference signals.

In some examples, the condition comprises: a difference between highest measured values related to power of the first set of reference signals and lowest measured values related to power measured of the first set of reference signals being less than a threshold difference value.

In some examples, the measured values related to power comprise at least one of: L1-RSRP values, or L1-SINR values.

In some examples, the threshold value and the threshold difference value are received from the network node. In some examples, the threshold value and the threshold difference value are comprised in the configuration.

In some examples, the means for determining whether the condition has been fulfilled based on the at least one measurement comprises: means for determining whether the condition has been fulfilled for a plurality of candidate UL SRS resource sets based on the at least one measurement; and means for selecting the at least one second UL SRS resource set from UL SRS resource sets of the plurality of candidate UL SRS resource sets that had their condition fulfilled, wherein the selecting is based on the at least one measurement.

In some examples, the apparatus is a communication device.

In some examples, the communication device is a user equipment.

According to an aspect, there is provided an apparatus comprising: means for providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission; and means for receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, the apparatus comprises: means for, based on the request, providing, to the communication device, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission. In some examples, one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.

In some examples, the at least one first UL SRS resource set is associated with at least one antenna panel of the communication device, and wherein the at least one second UL SRS resource set is associated with at least one further antenna panel of the communication device.

In some examples, the apparatus comprises: means for receiving, from the communication device, a capability indication of a capability of the communication device for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the capability indication is for one of: PUSCH, PUCCH, or both PUSCH and PUCCH.

In some examples, the apparatus comprises: means for receiving, from the communication device, the uplink transmission based on the at least one second UL SRS resource set.

In some examples, the apparatus comprises: means for receiving, from the communication device, a simultaneous multi-panel transmission based on the at least one second UL SRS resource set.

In some examples, the apparatus comprises: means for transmitting, to the communication device, at least one downlink reference signal.

In some examples, the apparatus is a network node.

In some examples, the network node is a base station.

According to an aspect, there is provided a method comprising: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission; performing at least one measurement on at least one reference signal; determining whether the condition has been fulfilled based on the at least one measurement; and based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different. In some examples, one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.

In some examples, the method comprises: providing, to the network node, a capability indication of a capability for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the capability is indicated either as relevant to PUSCH or PUCCH, or as a capability for both PUSCH and PUCCH.

In some examples, the method comprises: receiving, from the network node, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.

In some examples, the method comprises: performing the uplink transmission to the network node based on the at least one second UL SRS resource set.

In some examples, the method comprises: performing the uplink transmission to the network node based on the at least one second UL SRS resource set, wherein the uplink transmission being performed is a simultaneous multi-panel transmission.

In some examples, the performing at least one measurement on at least one reference signal comprises: performing the at least one measurement on at least one downlink reference signal resource; and comparing the at least one measurement to at least one previous measurement, wherein the at least one previous measurement is associated with measurements performed previously on downlink reference signal resources.

In some examples, the determining whether the condition has been fulfilled based on the at least one measurement comprises: determining whether the condition has been fulfilled for a plurality of candidate UL SRS resource sets based on the at least one measurement; and selecting the at least one second UL SRS resource set from UL SRS resource sets of the plurality of candidate UL SRS resource sets that had their condition fulfilled, wherein the selecting is based on the at least one measurement.

In some examples, the method is performed by a communication device.

In some examples, the communication device is a user equipment.

According to an aspect, there is provided a method comprising: providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission; and receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, the method comprises: based on the request, providing, to the communication device, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.

In some examples, the method comprises: receiving, from the communication device, a capability indication of a capability of the communication device for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the method comprises: receiving, from the communication device, the uplink transmission based on the at least one second UL SRS resource set.

In some examples, the method comprises: receiving, from the communication device, a simultaneous multi-panel transmission based on the at least one second UL SRS resource set.

In some examples, the method comprises: transmitting, to the communication device, at least one downlink reference signal.

In some examples, the method is performed by is a network node.

In some examples, the network node is a base station.

According to an aspect, there is provided an apparatus comprising: at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission; performing at least one measurement on at least one reference signal; determining whether the condition has been fulfilled based on the at least one measurement; and based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, the apparatus is caused to perform: providing, to the network node, a capability indication of a capability for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the apparatus is caused to perform: receiving, from the network node, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.

In some examples, the apparatus is caused to perform: performing the uplink transmission to the network node based on the at least one second UL SRS resource set.

In some examples, the apparatus is caused to perform: performing the uplink transmission to the network node based on the at least one second UL SRS resource set, wherein the uplink transmission being performed is a simultaneous multi-panel transmission.

In some examples, the apparatus is a communication device.

In some examples, the communication device is a user equipment.

According to an aspect, there is provided an apparatus comprising: at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform: providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission; and receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, the apparatus is caused to perform: based on the request, providing, to the communication device, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission. In some examples, one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.

In some examples, the apparatus is caused to perform: receiving, from the communication device, a capability indication of a capability of the communication device for event-based switching of antenna panels for transmissions using uplink channels.

In some examples, the capability indication is for one of: PUSCH, PUCCH, or both 30 PUSCH and PUCCH.

In some examples, the apparatus is caused to perform: receiving, from the communication device, the uplink transmission based on the at least one second UL SRS resource set.

In some examples, the apparatus is caused to perform: receiving, from the communication device, a simultaneous multi-panel transmission based on the at least one second UL SRS resource set.

In some examples, the apparatus is caused to perform: transmitting, to the communication device, at least one downlink reference signal. In some examples, the apparatus is a network node. In some examples, the network node is a base station.

According to an aspect, there is provided an apparatus comprising: circuitry configured to perform: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission; circuitry configured to perform: performing at least one measurement on at least one reference signal; circuitry configured to perform: determining whether the condition has been fulfilled based on the at least one measurement; and circuitry configured to perform: based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

According to an aspect, there is provided an apparatus comprising: circuitry configured to perform: providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission; and circuitry configured to perform: receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different. According to an aspect, there is provided a computer program comprising instructions, which when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission; performing at least one measurement on at least one reference signal; determining whether the condition has been fulfilled based on the at least one measurement; and based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

According to an aspect, there is provided a computer program comprising instructions, which when executed by an apparatus, cause the apparatus to perform at least the following: providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission; and receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different. A computer product stored on a medium may cause an apparatus to perform the methods as described herein.

A non-transitory computer readable medium comprising program instructions, that, 5 when executed by an apparatus, cause the apparatus to perform the methods as described herein.

An electronic device may comprise apparatus as described herein.

Various other aspects and further embodiments are also described in the following detailed description and in the attached claims.

According to some aspects, there is provided the subject matter of the independent claims. Some further aspects are defined in the dependent claims. The embodiments that do not fall under the scope of the claims are to be interpreted as examples useful for understanding the disclosure.

List of Abbreviations: AF: Application Function AMF: Access and Mobility Management Function AN: Access Network BS: Base Station CSI: Channel state information CN: Core Network DCI: Downlink control information DL: Downlink eNB: eNodeB gNB: gNodeB lloT: Industrial Internet of Things Layer one LTE: Long Term Evolution MAC: Medium access control MIMO: Multiple input multiple output MS: Mobile Station NEF: Network Exposure Function NG-RAN: Next Generation Radio Access Network NF: Network Function NR: New Radio NRF: Network Repository Function NW: Network PLMN: Public Land Mobile Network PDCCH: Physical Downlink Control Channel PUCCH: Physical Uplink Control Channel PUCCH: Physical Uplink Shared Channel RAN: Radio Access Network RF: Radio Frequency RRC: Radio resource control RS: Reference signal SMF: Session Management Function STxMP: Simultaneous Multi-panel SDM: Spatial division multiplexing SFN: Single frequency network TCI: Transmission configuration indication UE: User Equipment UDR: Unified Data Repository UDM: Unified Data Management UL: Uplink UPF: User Plane Function 3GPP: 3rd Generation Partnership Project 5G: 5th Generation 5GC: 5G Core network 5G-AN: 5G Radio Access Network 5GS: 5G System

Brief Description of Drawings

Some examples will now be described, by way of illustrative and non-limiting example only, with reference to the accompanying drawings in which: FIG. 1 shows a schematic representation of a 5G communication system; FIG. 2 shows a schematic representation of an apparatus for the 5G communication system of FIG. 1; FIG. 3 shows a schematic representation of a communication device; FIG. 4 shows an example signalling diagram between a communication device and a network node related to antenna panel switching; FIG. 5 shows an example signalling and operations diagram for a communication device and a network node related to antenna panel switching; FIG. 6 shows another example signalling and operations diagram for a communication device and a network node related to antenna panel switching; FIG. 7 shows an example method flow diagram performed by an apparatus; FIG. 8 shows another example method flow diagram performed by an apparatus; FIG. 9 shows an example method flow diagram performed by an apparatus; and FIG. 10 shows a schematic representation of a non-volatile memory medium storing instructions which when executed by a processor allow a processor to perform one or more of the steps of the method of FIGS. 7 to 9.

Detailed Description

Communications devices, such as user equipments (UEs), terminals and other mobile devices, are often configured to perform uplink (UL) transmissions towards network nodes (e.g., base stations). UL transmissions may be performed utilising one or more antennas (or antenna panels). Antennas are used to transmit and receive electromagnetic signals, such as radio waves. An antenna panel comprises one or more antennas.

Communication devices may comprise a single antenna (or antenna panel) that may be used for UL transmissions. However, in order to improve transmission and reception performance, many communication devices comprise a plurality of antennas (or antenna panels). Communication devices with a plurality antennas may benefit from signal processing techniques such as beamforming or spatial filtering.

In order to improve the reliability and robustness of UL transmissions, UL multi-panel transmission may be performed by suitable communication devices. An UL multi-panel transmission is a transmission performed by the communication device using two or more antenna panels simultaneously in the UL.

3GPP Rel-18 specifications such as TS 38.214 and TS 38.331 define support for simultaneous multi-panel (STxMP) physical uplink shared channel (PUSCH) and physical uplink control channel (PUCCH) transmission in single-TRP and multi-TRP environments. A TRP is a transmission receive point, such as for example, a base station.

To enable STxMP-based UL (e.g., PUSCH/PUCCH) operation, a UE provides TX beam reports based on configured downlink (DL) reference signal (RS) resources. Rel-18 TS 38.214 specification provides support for TX beam reporting based on downlink reference signal resource measurements by leveraging group-based beam reporting.

Based on UL TX beam reports, a network and UE are able to have a mutual understanding of potential UL TX beams to be used for STxMP based UL channel transmission. Then, based on these UL TX beam reports, the network dynamically indicates for the UE to transmit on uplink channels either with a single antenna panel, or simultaneously with multiple antenna panels.

3GPP Rel-18 specification TS 38.214 defines downlink control information (DCI) based dynamic switching of single-panel to multi-panel (codebook or non-codebook) based PUSCH transmission and multi-panel to single-panel PUSCH transmission. The Rel-18 specification defines that by using a DCI 0_1/0_2 codepoint associated with sounding reference signal (SRS) resource set indicator, a UE is indicated to dynamically to switch STxMP based PUSCH transmission from single-panel transmission to multi-panel transmission and vice versa. 3GPP Rel-18 TS 38.214 also defines an antenna panel switch between single antenna panel and simultaneous multi-antenna transmission for PUCCH based on higher layer parameter PUCCH-SpatialRelationInfo and apply-IndicatedTCIState. Here, TCI is representative of a transmission configuration indication.

In this manner, current 3GPP specifications provide support for network-controlled DL RS-based channel state information (CSI) measurements and CSI-reporting via UL channels for STxMP based PUSCH. The network is able to configure periodic or semi-persistent DL resources, or trigger aperiodic DL RS resources for UL transmission measurements. The network may also independently configure periodic (or semi-persistent, or aperiodic) CSI reporting via PUCCH/PUSCH.

To enable tracking of potential changes at the UE-side related to UL transmission antenna panel switching (e.g., UE rotation, UE position changing with respect to uplink TX beam-per-links associated with antenna panels and corresponding TRPs) the UE may be configured with CSI measurement and CSI reporting configuration with relatively short time periodicity. However, a shorter time periodicity may lead to extensive overhead in the terms of DL RS resources and UL resources associated with CSI reporting. Alternatively, a UE may be configured with a longer CSI reporting time periodicity, but this leads to a reduced tracking capability and a degradation of STxMP based PUSCH and/or PUCCH transmission. Stated differently, a longer periodicity may lead to fewer resources being used, but it may be slow for the UE to change between configurations. This may increase latency for communications. To reduce the problem of an increasing CSI-reporting overhead, event-based CSI-reporting provides may be considered. For event-based reporting, a UE may be configured with specific condition(s) which trigger the UE indicate to the network that a specific event has occurred at the UE-side. Based on indication received at the network, the network is then able to determine whether a new configuration should be activated in the UE, e.g., for uplink transmissions. However, there is no support in specifications for UL TX beam reporting.

One or more of the following examples aim to address one or more of the problems identified above.

In some examples, there is provided an apparatus (e.g., a communication device) that receives, from a network node (e.g., a base station), a configuration including a condition related to switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission. The apparatus performs at least one measurement on at least one reference signal, and determines whether the condition has been fulfilled based on the at least one measurement. Based on the determining, the apparatus transmits, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different. In some examples, there is provided an apparatus (e.g., a communication device) that receives, from a network node (e.g., a base station), a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission, and performs at least one measurement on at least one reference signal. The apparatus also determines whether the condition has been fulfilled based on the at least one measurement, wherein the condition is based on at least one of: measured values related to power of a first set of reference signals being a threshold value greater than measured values related to power of a second set of reference signals, or a difference between highest measured values related to power of the first set of reference signals and lowest measured values related to power of the first set of reference signals being greater than a threshold difference value. Based on the determining, the apparatus transmits, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

In some examples, the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets, or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set, or the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set, or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.

These examples will be described in more detail below, alongside FIGS. 4 to 6. Before explaining the examples in greater detail, an example communication device (as shown in FIG. 3) that is capable of performing uplink transmissions to a network node (e.g., multi-panel UL transmissions) and capable of switching between different antenna panels for UL transmissions. The communication device may be part of a communication system (as shown in FIG. 1). The communication device is able to communicate with one or more of the entities of the communication system (as shown in FIG. 1) via an apparatus (as shown in FIG. 2), which may be part of/comprised in a network node (e.g., a base station). As described above, a base station and a communication device may communicate with each other, such that the communication device is able to switch between different antenna panels for UL transmissions to the network.

Certain general aspects of the communication system and the communication device are briefly explained with reference to FIGS. 1 to 3 to assist in understanding the technology underlying the described examples.

to FIG. 1 shows a schematic representation of a 5G communication system 100. The wireless communication system 100 comprises one or more communication devices 102 such as user equipments (UEs), or terminals. The wireless communication system 100 comprises a 5G system (5GS). The 5GS comprises a 5G radio access network (5G-RAN) 106, a 5G core network (5GC) 104 comprising one or more network functions (NF), one or more application functions (AFs) 108, and one or more data networks (DNs) 110.

The 5G-RAN 106 may comprise one or more gNodeB (gNB) distributed unit (DU) functions connected to one or more gNodeB (gNB) centralized unit (CU) functions.

The 5GC 104 comprises an access and mobility management function (AMF) 112, a session management function (SMF) 114, an authentication server function (AUSF) 116, a user data management (UDM) 118, a user plane function (UPF) 120, a network exposure function (NEF) 122 and/or other NFs. Some of the examples as shown below may be applicable to 3GPP 5G standards. However, some examples may also be applicable to 5G-advanced, 4G, 3G and other 3GPP standards.

In a wireless communication system 100, such as that shown in FIG. 1, communication devices 102, such as for example, terminals, user apparatuses, user equipments (UE), and/or machine-type communication devices are provided with wireless access via at least one base station or similar wireless transmitting and/or receiving node or point. The communication device 102 is provided with an appropriate signal receiving and transmitting apparatus for enabling communications, for example enabling access to a communication network or communications directly with other devices. The communication device 102 may access a carrier provided by a base station or access point, and transmit and/or receive communications on the carrier.

FIG. 2 illustrates an example of an apparatus 200. The apparatus 200 may be for the 5G communication system of FIG. 1. The apparatus 200 may be for controlling a function of one or more network entities and/or network functions, such as the entities of the 5G-RAN or the 5GC as illustrated on FIG. 1. The apparatus 200 comprises at least one random access memory (RAM) 211a, at least one read only memory (ROM) 211b, at least one processor 212, 213 and an input/output interface 214. The at least one processor 212, 213 is coupled to the RAM 211a and the ROM 211b. The at least one processor 212, 213 may be configured to execute instructions, such as for example an appropriate software code 215. The software code 215 may for example allow to perform one or more steps to perform one or more of the present aspects or examples. The software code 215 may be stored in the ROM 211b. The apparatus 200 may be interconnected with another apparatus 200 controlling another entity/function of the 5G-AN or the 5GC. . In some examples, apparatus 200 may be configured to provide one or more functions of the 5G-AN or the 5GC. For example, apparatus 200 may be configured to perform at least some functionality of a particular function of the 5G-AN or the 5GC. For example, apparatus 200 may be configured to operate as a particular function of the 5G-AN or the 5GC. In alternative examples, apparatus 200 may be configured to perform at least some functionality of two or more functions of the 5G-AN and/or the 5GC. For example, apparatus 200 may be configured to operate as two or more functions of the 5G-AN and/or the 5GC. The apparatus 200 may comprise one or more circuits, or circuitry (not shown) which may be configured to perform one or more of the present aspects or examples.

FIG. 3 illustrates an example of a communication device 300. The communication device 300 may be similar to the communication device 102 illustrated in FIG. 1. The communication device 300 may be provided by any device capable of sending and receiving radio signals. Non-limiting examples of a communication device 300 are a user equipment, a terminal, a mobile station (MS) or mobile device such as a mobile phone or what is known as a 'smart phone', a computer provided with a wireless interface card or other wireless interface facility (e.g., USB dongle), a personal data assistant (PDA) or a tablet provided with wireless communication capabilities, a machine-type communications (MTC) device, a Cellular Internet of things (CloT) device, or a terrestrial/maritime/aerial vehicle such as a car, a truck, a boat, an air plane, or a drone, or any combinations of these or the like. The communication device 300 may provide, for example, communication of data for carrying communications. The communications may be one or more of voice, electronic mail (email), text message, multimedia, data, machine data and so on.

The communication device 300 may receive signals over an air or radio interface 307 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. In FIG. 3, a transceiver apparatus is designated schematically by block 306. The transceiver apparatus 306 may be provided for example by means of a radio part and associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

The communication device 300 may be provided with at least one processor 301, at least one memory ROM 302a, at least one RAM 302b and other possible components 303 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices. The at least one processor 301 is coupled to the RAM 302b and the ROM 302a. The at least one processor 301 may be configured to execute instructions, such as for example an appropriate software code 308. The software code 308 may for example allow to perform one or more of the present aspects. The software code 308 may be stored in the ROM 302a.

The communication device 300 may comprise one or more circuits, or circuitry (not shown) which may be configured to perform one or more of the present aspects or examples.

The processor, storage and other relevant control apparatus may be provided on an appropriate circuit board and/or in chipsets. This feature is denoted by reference 304. The communication device may optionally have a user interface such as keypad 305, touch sensitive screen or pad, combinations thereof or the like. Optionally one or more of a display, a speaker and a microphone may be provided depending on the type of the device.

As described above, in some examples, a communication device (e.g., a UE) may be configured to perform an UL transmission to a network node using an UL channel (e.g., PUSCH or PUCCH), wherein the communication device utilises a single (i.e., one) antenna panel of the communication device. Alternatively, the communication device may be configured to perform the UL transmission utilising multiple (or multi) (i.e., two or more) antenna panels of the communication device. In examples, a communication device may determine when it is suitable to switch between antenna panels of the communication device for UL transmissions to a network node based on measurements performed at the communication device.

A communication device may comprise a plurality of antenna panels. For example, a communication device may comprise at least one antenna panel on each side of the communication device. Each antenna panel of the communication device comprises at least one antenna. Each antenna panel may be associated with an UL SRS resource set.

In the following, the terms 'single antenna panel' and 'single-panet may be used interchangeably. Furthermore, the terms 'multi antenna panel' and 'multi-panet may be used interchangeably.

Each antenna panel of the communication device is associated with a resource set for UL SRS (referred to herein as 'UL SRS resource set'). For example, a first panel of a UE is associated with a first UL SRS resource set, and a second panel of the UE is associated with a second UL SRS resource set, wherein the first and second UL SRS resource sets are different. In this manner, a UE configured with multi-panel operation will be associated with at least two UL SRS resource sets.

SRS is a reference signal for UL (i.e., transmitted by UE) that may be used by a network node in order to perform channel quality estimation for UL. SRS is configured using one or more SRS resource sets where each SRS resource set contains one or more (e.g., up to 16) SRS resources. A UE may be configured with multiple SRS resource sets in each component carrier (CC). For example, a CC may be configured with one or more SRS resource sets for codebook-based uplink, one or more SRS resource sets for non-codebookbased uplink, one or more SRS resource sets for antenna switching, and/or one or more SRS resource sets for beam management.

In the case of codebook-based transmissions, a UE transmits a set of non-precoded SRS. A network node uses this SRS to select an appropriate antenna port for an uplink channel (e.g., PUSCH), and select an appropriate rank and precoding weight. The network node then provides feedback to UE in terms of, for example, an SRS resource indicator (SRI), rank indicator (RI) and transmit precoding matrix indicator (TPM I).

In this manner, each antenna panel of a communication device (e.g., a UE) is associated with an UL SRS resource set.

In some examples, a communication device (e.g., a UE) is configured with event-based (or condition-based) reporting for a UE event, wherein the UE indicates (or recommends) to a network node related to the switching of current simultaneous multi-panel UL channel transmission (e.g., PUSCH, PUCCH) to single-panel uplink channel transmission. Stated differently, the UE indicates to the network node the switching from two UL SRS resource sets to one SRS resource set. Stated differently, the UE indicates to the network node the switching from a first TCI state to a second TCI state, wherein the first and second TCI states are different (e.g., the indication indicates: apply-IndicatedTCIState = 'both', to first' or 'second' = apply-I ndicatedTClState).

In some examples, a communication device (e.g., a UE) is configured with event-based (or condition-based) reporting for a UE event, wherein the UE indicates (or recommends) to a network node related to the switching of current single-panel UL channel transmission (e.g., PUSCH, PUCCH) to multi-panel uplink channel transmission. Stated differently, the UE indicates to the network node the switching from one UL SRS resource set to two SRS resource sets. Stated differently, the UE indicates to the network node the switching from apply-I ndicatedTCIState ="first'/'second' to apply-IndicatedTCIState ='both' operation.

In some examples, a communication device (e.g., a UE) is configured with event-based (or condition-based) reporting for a UE event, wherein the UE indicates (or recommends) to a network node related to the switching of current simultaneous multi-panel UL channel transmission (e.g., PUSCH, PUCCH) to another simultaneous multi-panel uplink channel transmission. Stated differently, the UE indicates to the network node the switching from two UL SRS resource sets to another two SRS resource sets. Stated differently, the UE indicates to the network node the switching from apply-IndicatedTCIState = 'both' to apply-IndicatedICIState = 'both' operation.

These examples will be described in more detail below.

In some examples, there is a signalling exchange between the communication device-side and the network side to ensure that the communication device has the capability for event-based antenna switching. Suitable configuration(s) for event-based antenna switching may then be sent to the communication device. In other examples, it may be assumed that the communication device does have the suitable capability. Some example signalling is shown in FIG. 4.

FIG. 4 shows an example signalling diagram between a communication device and a network node related to antenna panel switching. In some examples, the communication device is a UE, and the network node is a base station. In other examples, the communication device may be a terminal or other mobile device, and/or the network node may be a gNodeB or TRP.

At 5401, the UE provides (or sends), to the base station, an indication that the UE has the capability for event-based (or condition-based) switching of antenna panels for UL transmissions. Stated differently, the indication is for the capability of event-based switching of UL SRS resource sets for UL transmissions.

The capability may be indicated either as for PUSCH or PUCCH, or a capability for both PUSCH and PUCCH.

The indication may be provided via radio resource control (RRC) signalling. In other examples, any suitable signalling protocol is used.

At S402, the base station provides, to the UE, a configuration including a condition for switching between UL SRS resource sets to use for an UL transmission. The condition is associated with an event. When the condition is fulfilled, then the event is 'triggered'. The triggering of the event may have an associated action. For example, when the event is triggered, the UE may be configured to provide an indication to the base station.

In some examples, the configuration provided to the UE comprises a plurality of events (e.g., different events), wherein each of the events has at least one condition associated with the respective event.

The configuration may be associated with PUSCH, or PUCCH, in some examples. In other examples, the configuration is associated with both PUSCH and PUCCH.

In some examples, the event (that has been configured for the UE) defines the condition (or conditions) based on 'new' DL reference signal measurements (e.g., non-zero power channel state information reference signal (NZP-CSI-RS)/synchronisation signal block (SSB) measurements) and 'previous' DL reference signal measurements. Stated differently, the condition is associated with a comparison between two sets of measurements. Based on the event, for example, the UE may indicate (e.g., via layer 1 (L1), or medium access control (MAC), or RRC signalling) to the network that at least one antenna panel is recommended to be switched at the UE-side to a different configuration.

This is described in more detail below alongside FIGS. 5 and 6.

FIG. 5 shows an example signalling and operations diagram for a communication device and a network node related to antenna panel switching. In the example of FIG. 5, the communication device is initially configured for multi-panel UL channel transmission, which may be switched to single-panel or to a different multi-panel. In this example, the communication device is a UE. In other examples, the communication device is a terminal, mobile device, etc. At S501, the network node provides (or sends), to the UE, at least one UL SRS resource set. SRS resources of the at least one UL SRS resource set may be configured with information for following a TCI state (also referred to as 'follow TO state information'). The follow TCI state information is used when a network indicates a TCI state(s) via DCI. UL SRS resource sets having an information element (1E) corresponding to the TCI state are to apply/use the indicated TCI states and corresponding spatial source RS (e.g., QCL-typeD source RS) as a spatial reference for transmission of SRS resources associated with the UL SRS resource set.

In some examples, the network node configures the UE with a plurality of UL SRS resource sets, including: UL SRS resource sets for codebook UL, UL SRS resource sets for non-codebook UL, and UL SRS resource sets for antenna switching.

At S502, the network node provides, to the UE, a configuration for measurement and reporting based on DL reference signals for UL STxMP. In some examples, at least one of PUSCH or PUCCH are configured with STxMP.

S501 and S502 may be provided using RRC signalling, for example.

At S503, the network node provides, to the UE, a configuration comprising a condition for switching between UL SRS resource sets to use for an UL transmission. The condition is associated with an event to be triggered.

The configuration is associated with at least one uplink channel (e.g., PUSCH and/or PUCCH).

At S504, the network node provides periodic or semi-persistent DL RSs to the UE.

NZP-CSI-RS and SSB are examples of DL RSs.

At S505, the UE provides a report(s) (e.g., a CSI report) with the N 'best' UL TX beams that have been measured by the UE. The 'best' UL TX beams are determined based on the DL reference signals provided by the network node. The report may be provided periodically or semi-persistently. Semi-Persistent reporting may be regarded as a combination of periodic and aperiodic reporting. For semi-persistent reporting, a first cycle may be similar to aperiodic (e.g., a report is sent in response to a trigger). Once the cycle is triggered, subsequent reports are sent periodically.

In this context, the 'best' beams may be those beams determined to be associated with the highest power, lowest noise, etc. The signalling of S505 may be performed according to the 3GPP Re1-18 CSI reporting framework via PUCCH.

At S506, based on the report (or reports) from the UE, the network node determines TCI states for UL STxMP.

At S507, the network node provides, to the UE, an indication of a set of TCI states to be activated. The network node may provide the indication via a MAC control element (CE), in some examples. The TCI states may be for DL, joint UL-DL and/or UL.

At S508, based on the indication received in S507, the UE activates the TCI states associated with UL TX antenna panels of the UE. In this manner, the UE activates one or more antenna panels to be used for UL transmissions, according to the indication from the network 15 node.

At S509, the UE provides, to the network node, hybrid automatic repeat request (HARQ) acknowledgments or negative-acknowledgments (ACK/NACK) related to the activated TCI states. The HARQ ACK/NACK is provided on an uplink channel, such as PUSCH or PUCCH.

At S510, the network node provides, to the UE, an indication of a set of TCI codepoints for UL (or joint UL-DL). The indication may be provided via downlink control information (DCI), in some examples. For example, DCI format 1_0/2_0.

At S511, the UE provides, to the network node, periodic or semi-persistent UL SRS for PUSCH. The SRS being provided by the UE may be for associated with codebook, non-codebook, and/or antennas switching.

At S512, the network node provides, to the UE, a grant for PUSCH. The grant may be provided via a physical downlink control channel (PDCCH). For example, format 0_1 or 0_2.

At S513, the UE performs STxMP using an uplink channel (e.g., PUSCH or PUCCH) towards the network node. The STxMP may be associated with spatial division multiplexing (SDM) or single frequency network (SFN). The STxMP transmission may be codebook or non-codebook.

At S514, the network node provides, to the UE, a HARQ ACK/NACK via PDCCH related to the STxMP PUSCH.

At S515, the UE sets a STxMP status at the UE to 'multi-panel'. The status of 'multi-panel' indicates that multiple antenna panels are being used for STxMP.

At S516, the UE measures DL RSs to determine at least one 'best' (e.g., K 'best') resource (or resource pairs) based on measured values related to power (e.g., Li-reference signal received power (RSRP) or L1-signal to interference plus noise ratio (SINK)) associated with the measured DL RSs. The value of K may be configured by the network node.

In this context, a resource pair refers to DL RS resources (e.g. NZP-CSI-RS or SSB) associated with two different transmit receive points (TRPs) or two different DL TX antenna panels.

NZP-CSI-RS and SSB are examples of DL RSs that may be measured by the UE.

At S517, the UE determines whether the condition (of the event) has been fulfilled based on the measurements on the DL RSs.

At S518a, the UE determines that the condition of the event has been fulfilled and is related to switching (from multi-antenna) to another multi-antenna panel (i.e., another multi-UL SRS resource sets).

At 5519a, the UE provides, to the network node, a request (or an indication)related to performing a switch from two 'first' UL SRS resource sets (i.e., multi-panel) to another two second' UL SRS resource sets (also multi-panel) to be used for an UL TX.

The UE may also provide an identity (ID) of a corresponding DL RS. In some example, the indication includes the ID of the corresponding DL RS. In some examples, the indication includes an IDs for measured DL RS resource associated with a new resource pair, wherein at least one of the DL RS resources is different with respect to DL RS resources associated with indicated TCI state(s).

The SRS resources of the first sets are different to the SRS resources of the second sets. In some examples, there are no overlapping resources in the SRS resources of the first sets and the SRS resources of the second sets. In some examples, the SRS resources of the first sets are different to the SRS resources of the second sets, wherein there is at least one overlapping resource. As an example of different resource with overlapping, the first sets are associated with two DL RSs, namely DL RSs <CSI-RS#3, CSI-RS#7> and then, based on DL measurements, the UE determines a 'better' DL RS pair of <CSI-RS#3, CSI-RS#9>, which fulfils the condition and triggers the event. CSI-RS (e.g., CSI-RS#3) may be measured from different antenna panels (and thus different UL SRS resource sets) with respect to other antenna panels used for UL SRS and PUSCH transmission. It should be understood that this is an example only, to aid in the understanding of the disclosure.

The indication related to performing a switch may be considered to be a recommendation (or similar) from the UE to the network node. The UE may not switch to the (recommended) another two UL SRS resource sets until the UE has been instructed by the network node, in some examples.

Instead of S518a and S519a, in other examples, there are S518b, S519b and S520.

In this manner, S518b, 5519b and S520 are alternatives to S518a and S519a.

At S518b, the UE determines that the condition of the event has been fulfilled and is related to switching (from multi-panel) to single-panel (i.e., single UL SRS resource set).

At S519b, the UE provides, to the network node, a request (or an indication)related to performing a switch from two 'first UL SRS resource sets (i.e., multi-panel) to a 'second' UL SRS resource set (single-panel) to be used for an UL TX. The indication includes an identity of a corresponding DL RS.

The SRS resources of the first sets are different to the SRS resources of the second set. In some examples, there are no overlapping resources in the SRS resources of the first sets and the SRS resources of the second set. In some examples, the SRS resources of the first sets are different to the SRS resources of the second set, wherein there is at least one overlapping resource.

At S520, the UE sets the current STxMP status at the UE to 'single-panel'. In some examples, the UE sets the current STxMP status at the UE to 'single-panel' in response to receiving an indication (or confirmation) from the network that the request of S519b has been accepted.

At S521, the network node provides, to the UE, an indication of a 'new' set of ICI codepoints for UL (or joint UL-DL). The indication may be provided via DCI. For example, DCI format 1_0 or 2_0.

At S522, the UE provides, to the network node, aperiodic UL SRS for PUSCH. The SRS being provided by the UE may be for associated with codebook, non-codebook, and/or antennas switching.

At S523, the network node provides, to the UE, a grant for PUSCH via PDCCH (e.g., format 0_1 or 0_2.). The network node also provides information related to using either multi panel (i.e., multiple UL SRS resource sets) or single panel (i.e., a single UL SRS resource set) for STxMP. For example, when the UE provides the request of S519a, the network node may provide information related to multi-panel, including information to switch to the two second UL SRS resource sets. For example, when the UE provides the request of S519b, the network node may provide information related to single-panel, including information to switch to the second UL SRS resource set.

Stated differently, based on the request (e.g., S519a, 3519b), the network node provides information comprising an indication, to the UE, to switch UL SRS resource sets. The indication may be considered to be an acceptance of the request (provided by the UE).

At S524, based on the information (from S523), the UE performs STxMP using the multi-panel or the single-panel (as indicated in the information).

It should be understood that, in other examples, one or more of the steps of FIG. 5 may not be performed or may be performed in a different order.

FIG. 6 shows another example signalling and operations diagram for a communication device and a network node related to antenna panel switching. In the example of FIG. 6, the communication device is initially configured for single-panel UL channel transmission, which may be switched to multi-panel or to a different single-panel.

At S601, the network node provides (or sends), to the UE, at least one UL SRS resource set, with SRS resources configured with follow TCI state information.

At S602, the network node provides, to the UE, a configuration for measurement and reporting based on DL reference signals for UL STxMP. In some examples, at least one of PUSCH or PUCCH are configured with STxMP.

S601 and S602 may be provided using RRC signalling, for example.

At S603, the network node provides, to the UE, a configuration comprising a condition for switching between UL SRS resource sets to use for an UL transmission. The condition is associated with an event to be triggered.

At S604, the network node provides periodic or semi-persistent DL RSs to the UE. 20 NZP-CSI-RS and SSB are examples of DL RSs.

At 5605, the UE provides a report(s) (e.g., a CS! report) with the N 'best' UL TX beams that have been measured by the UE. The 'best' UL TX beams are determined based on the DL reference signals provided by the network node. The report may be provided periodically or semi-persistently. In this context, the 'best' beams may be those beams determined to be associated with the highest power, lowest noise, etc. The signalling of S605 may be performed according to the 3GPP Rel-18 CS! reporting framework via PUCCH.

At S606, based on the report (or reports) from the UE, the network node determines TCI states for UL STxMP.

At S607, the network node provides, to the UE, an indication of a set of TCI states to be activated. The network node may provide the indication via a MAC control element (CE), in some examples. The TCI states may be for DL, joint UL-DL and/or UL.

At S608, based on the indication received in S607, the UE activates the TCI states associated with UL TX antenna panels of the UE. In this manner, the UE activates one or more antenna panels to be used for UL transmissions, according to the indication from the network node.

At S609, the UE provides, to the network node, hybrid automatic repeat request (HARQ) acknowledgments or negative-acknowledgments (ACK/NACK) related to the activated TCI states. The HARQ ACK/NACK is provided on an uplink channel, such as PUSCH or PUCCH.

At S610, the network node provides, to the UE, an indication of a set of TCI codepoints for UL (or joint UL-DL). The indication may be provided via downlink control information (DCI), in some examples. For example, DCI format 1_0/2_0.

At S611, the UE provides, to the network node, periodic or semi-persistent UL SRS for PUSCH. The SRS being provided by the UE may for associated with codebook, non-codebook, and/or antennas switching.

At S612, the network node provides, to the UE, a grant for PUSCH. The grant may be provided via a physical downlink control channel (PDCCH). For example, format 0_1 or 0_2.

At S613, the UE performs STxMP using PUSCH towards the network node. The STxMP may be associated with spatial division multiplexing (SDM) or single frequency network (SFN). The STxMP transmission may be codebook or non-codebook.

At S614, the network node provides, to the UE, a HARQ ACK/NACK via PDCCH related to the STxMP PUSCH.

At S615, the UE sets a STxMP status at the UE to 'single-panel'. The status of 'single-panel' indicates that multiple antenna panels are being used for STxMP.

At S616, the UE measures DL RSs to determine at least one 'best' (e.g., K 'best') resource (or resource pairs) based on measured values related to power (e.g., L1-reference signal received power (RSRP) or L1-signal to interference plus noise ratio (SINR)) associated with the measured DL RSs. The value of K may be configured by the network node.

NZP-CSI-RS and SSB are examples of DL RSs that may be measured by the UE.

At S617, the UE determines whether the condition (of the event) has been fulfilled based on the measurements on the DL RSs.

At S618a, the UE determines that the condition of the event has been fulfilled and is related to switching (from single-antenna) to another single-antenna panel (i.e., another single-UL SRS resource set).

At S619a, the UE provides, to the network node, a request (or an indication)related to performing a switch from a 'first' UL SRS resource set (i.e., single-panel) to another 'second' UL SRS resource set (also single-panel) to be used for an UL TX. The indication includes an identity of a corresponding DL RS.

The SRS resource (or resources) of the first set is different to the SRS resource (or resources) of the second set. In some examples, there are no overlapping resources in the SRS resources of the first set and the SRS resources of the second set. In some examples, the SRS resources of the first set are different to the SRS resources of the second set, wherein there is at least one overlapping resource. As an example of different resources, the first set is associated with a DL RS, namely DL RSs <CSI-RS#7> and then, based on DL measurements, the UE determines a 'better' DL RS of <CSI-RS#9>, which fulfils the condition and triggers the event. It should be understood that this is an example only, to aid in the

understanding of the disclosure.

The indication related to performing a switch may be considered to be a recommendation (or similar) from the UE to the network node.

Instead of S618a and S619a, in other examples, there are S618b, S619b and S620. In this manner, S618b, S619b and S620 are alternatives to S618a and S619a.

At S618b, the UE determines that the condition of the event has been fulfilled and is related to switching (from single-panel) to multi-panel (i.e., multiple UL SRS resource sets). At S619b, the UE provides, to the network node, a request (or an indication)related to performing a switch from a 'first' UL SRS resource set (i.e., single-panel) to a two 'second' UL SRS resource sets (multi-panel) to be used for an UL TX. The indication includes an identity of a corresponding DL RS.

At S620, the UE sets the current STxMP status at the UE to 'single-panel'. In some examples, the UE sets the current STxMP status at the UE to 'single-panel' in response to receiving an indication (or confirmation) from the network that the request of S519b has been accepted.

At S621, the network node provides, to the UE, an indication of a 'new' set of ICI codepoints for UL (or joint UL-DL). The indication may be provided via DCI. For example, DCI format 10 or 20.

At S622, the UE provides, to the network node, aperiodic UL SRS for PUSCH. The SRS being provided by the UE may be for associated with codebook, non-codebook, and/or antennas switching.

At S623, the network node provides, to the UE, a grant for PUSCH via PDCCH (e.g., format 0_1 or 0_2.). The network node also provides information related to using either multi panel (i.e., multiple UL SRS resource sets) or single panel (i.e., a single UL SRS resource set) for STxMP. For example, when the UE provides the request of S619a, the network node may provide information related to single-panel, including information to switch to the 'second' UL SRS resource set. For example, when the UE provides the request of S619b, the network node may provide information related to multi-panel, including information to switch to the two 'second' UL SRS resource sets.

Stated differently, based on the request (e.g., S619a, 3619b), the network node provides information comprising an indication, to the UE, to switch UL SRS resource sets. The indication may be considered to be an acceptance of the request (provided by the UE).

At S624, based on the information (from S623), the UE performs STxMP using the single-panel or the multi-panel (as indicated in the information).

It should be understood that, in other examples, one or more of the steps of FIG. 6 may not be performed or may be performed in a different order.

The determination of whether the condition for an event has been fulfilled will now be described in more detail below. This determination is shown in S517 of FIG. 5 and S617 of FIG. 6.

In some examples, the UE performs at least one measurement on at least one DL reference signal and then compares the at least one measurement to at least one previous measurement. The at least one previous measurement is associated with measurements performed previously on downlink reference signal resources. The at least one measurement and the at least one previous measurements are associated with different configurations or different DL RSs. Stated differently, the UE is performing 'new' measurements and comparing those measurements to previous' measurements associated with the current configuration at the UE.

In some examples, the condition is based on measured values related to power (e.g., L1-RSRP/L1-SINR) of first DL RS being a threshold value greater than measured values related to power of second DL RS. When the measured values related to power of the first DL RS are greater, by the threshold value, compared to the measured values related to power of second DL RS then the condition is fulfilled.

In some examples, the condition is based on a difference between highest measured values measured related to power of first DL RS and lowest measured values related to power measured of the first DL RS being greater or less than a threshold difference value. When the difference is less than (or equal to) the threshold difference, then the condition is fulfilled.

The determination of the condition being fulfilled, and the subsequent switching between antenna panels will now be described in more detail.

In some examples, the event that has been configured at the UE is associated with switching from single-panel to multi-panel operation for transmission over an uplink channel (e.g., PUCCH and/or PUCCH). In other examples, the event that has been configured at the UE is associated with switching from multi-panel to another (different) multi-panel operation for transmission over an uplink channel. For events associated with single-panel to multi-panel, or multi-panel to multi-panel, one or more of the following may apply: In some examples, for each of the K 'best' resource pairs, the UE determines whether the condition for the event is fulfilled. For a resource pair, when the UE determines that L1-RSRP or L1-SINR value associated with a DL RS resource measurement (corresponding to the resource pair) are X dB larger (e.g., a. X dB) than L1-RSRP or L1-SINR values of DL RS as QCL-typeD source associated with the indicated TCI-states (e.g., from 5507/S607) for simultaneous uplink transmission, then the resource pair is determined to be valid. A 'valid' resource pair is one that has been determined to be suitable for use for UL transmissions.

Stated differently, when measurements associated with the 'candidate' resource pair are above a threshold amount compared to measurements of a current configuration, then the UE determines candidate resource pair to be 'valid'.

In some examples, the value of X (which is the threshold value) is associated with hig her layer parameter ThesholdSwitchSingletoMultiPanel or ThesholdSwitchMultitoMultiPanel (depending on the event) which is configured by the network node. In other examples, the parameter for the threshold value has any other

suitable name.

In some examples, for each of the K 'best' resource pairs, the UE determines whether the condition for the event is fulfilled. For a resource pair or set, when the UE determines a (maximum) power difference between maximum and minimum values of L1-RSRP values or a (maximum) power difference between maximum and minimum values of L1-SIN R values associated with DL RSs (corresponding to the resource pair), is less than or equal to a threshold difference (e.g., X_range dB) and a threshold value (e.g., X dB) higher than or equal to L1-RSRP or L1-SINR values of DL RSs as QCLtypeD source associated with the indicated TCI-states for simultaneous uplink transmission, then the resource pair is determined to be valid.

The 'candidate' resource pairs may be associated with different antenna panels of the UE. The value of the threshold value (e.g., X) may be associated with higher layer parameter The resholdSwitchSingletoMultiPanel ThesholdSwitchMultitoMultiPanel. The value of the threshold difference (e.g., X range) may be associated with higher layer parameter PowerDifferenceToSwitchSingleToMultiPanel PowerDifferenceToSwitchMultiToMultiPanel (dependent on the event). The parameters may be configured by the network. In other examples, the parameters have any other suitable name.

Alternatively, or additionally, in some examples, the condition associated with the event may also include a counter for an antenna panel combination. The counter is increased until a condition is fulfilled. When the counter reaches a network configured value, the antenna panel is considered as valid. After being considered as valid, the value of the counter may be reset to zero. The network node may configure the counter to use as an additional condition for the UE to determine candidate as valid, in some examples.

Alternatively, or additionally, in some examples, the condition may include a counter for a common value which is increased when any one of the K best resource pairs fulfils the condition. When the value of the counter reaches a network configured value, the antenna panel is considered as valid. After the counter has reached the configured value and the antenna panel is valid, then the counter may be reset to zero.

The network node may configure the (common) counter to use as an additional condition for the UE to determine candidate as valid.

Once the UE has determined at least one resource pair that is 'valid', then the UE selects the 'best' resource pair from the different candidates. In some examples, when a single resource pair is determined to be valid then the single resource pair is selected. When the UE is selecting from a plurality of resource pairs that are valid, then the 'best' resource pair may be, for example, the resource pair associated with the highest measured values related to power (e.g., highest L1-RSRP or L1-SINR). When the UE has selected a resource pair, the UE sends an indication message to the network node that STxMP PUSCH is recommended to be switched from single panel to multi-panel transmission. The indication may include a corresponding identity for the DL RS.

In some examples, the event that has been configured at the UE is associated with switching from multi-panel to single-panel operation for transmission over an uplink channel (e.g., PUSCH and/or PUCCH). For events associated with multi-panel to single-panel, one or more of the following may apply: In some examples, for each of the K 'best resource pairs, the UE determines whether the condition for the event is fulfilled. For a resource pair or set, when the UE determines that L1-RSRP or L1-SINR values associated with a DL RS (corresponding to the resource pair) are a threshold value larger (e.g., Y dB) than L1-RSRP or L1-SINR values of DL RS as QCL-typeD source associated with the indicated TCI-states (e.g., from S507/5607) for simultaneous uplink transmission, then the resource pair is determined to be valid. A 'valid' resource pair is one that has been determined to be suitable for use for UL transmissions.

In some examples, the value of Y (which is the threshold value) is associated with higher layer parameter ThesholdSwitchMultitoSinglePanel which is configured by the network node. In other examples, the parameter for the threshold value has any other suitable name.

Alternatively, or additionally, in some examples, the condition may include a counter for a common value which is increased when any one of the K best resource pairs fulfils the condition. When the value of the counter reaches a network configured value, the antenna panel is considered as valid. After the counter has reached the configured value and the antenna panel is valid, then the counter may be reset to zero. The network node may configure the (common) counter to use as an additional condition for the UE to determine candidate as valid.

Once the UE has determined at least one resource pair that is 'valid', then the UE selects the 'best' resource pair from the different candidates. In some examples, when a single resource pair is determined to be valid then the single resource pair is selected. When the UE is selecting from a plurality of resource pairs that are valid, then the 'best' resource pair may be, for example, the resource pair associated with the highest measured values related to power (e.g., highest L1-RSRP or L1-SINR).

When the UE has selected a resource pair, the UE sends an indication message to the network node that STxMP PUSCH is recommended to be switched from multi panel to single-panel transmission. The indication may include a corresponding identity for the DL RS.

In some examples, at least one of a threshold value or threshold difference is obtained by a UE. For example, the threshold value or threshold difference may be determined by the UE, or may be preconfigured at the UE.

When the UE is in single-panel transmission mode, the UE continues to determine a (maximum) power difference between maximum and minimum value of measured L1-RSRP values or measured L1-SINR values associated with a resource pair of DL RS. When the power difference is less or equal to the (UE-determined) threshold difference (e.g., X_range dB), and a respective L1-RSRP value or a L1-SINR value is the threshold value (e.g., X dB) higher than a respective L1-RSRP value or a L1-SINS value of DL RS as QCL-typeD source associated with indicated TCI-state for uplink transmission, then the resource pair is considered to be valid.

The value of X and X_range may be determined by the UE as a threshold to switch from single panel to multi-panel transmission and a power difference to switch from single panel to multi-panel transmission, respectively.

When UE is in multi-panel transmission mode, and when the UE determines that measured L1-RSRP/L1-SINR values associated with resource pair of DL RS are the threshold value greater than or equal to (e.g., a Z dB) to respective measured L1-RSRP/L1-SINR values of DL RS as QCL-typeD source associated with indicated TCI-states for simultaneous uplink transmission, then the resource pair is considered to be valid. Here, the value of Z (the threshold value) may be determined by the UE.

One or more of the examples described above have the advantage of a reduced uplink resource overhead and latency associated with beam reporting. Furthermore, one or more of the examples have the advantage of reducing UL SRS resource overhead and latency.

The event-based reporting for antenna panel switching enables these advantages by reducing periodic reporting which may include reporting known (or the same) information with respect to a previous reporting instance. The event-based reporting thus leads to reduced uplink resource overhead. Furthermore, the event-based reporting enables a reduced latency for reporting, particularly when compared to periodic reporting with a long periodicity because configured events will trigger reporting once a certain triggering condition is fulfilled which enables faster delivery of DL RS measurement results to network.

FIG. 7 shows an example method flow performed by an apparatus. The apparatus may be a communication device. For example, the communication device may be one of a UE, a terminal, a mobile device, or tablet device.

In S701, the method comprises: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission.

In S703, the method comprises: performing at least one measurement on at least one reference signal; In S705, the method comprises: determining whether the condition has been fulfilled based on the at least one measurement.

In S707, the method comprises: based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

It should be understood that, in some examples, one or more additional method steps are included in the method flow of FIG.7 and are performed by the apparatus. In some examples, one or more of the method steps of FIG. 7 detailed above may not be performed, or may be performed in a different order.

FIG. 8 shows an example method flow performed by an apparatus. The apparatus may be a network node. For example, the network node may be one of: a base station, a gNB, a core network function, or other network entity.

In S801, the method comprises: providing, to a communication device, a configuration including a condition related to the communication device switching between UL SRS resource sets to use for an uplink transmission.

In S803, the method comprises: receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

It should be understood that, in some examples, one or more additional method steps are included in the method flow of FIG.8 and are performed by the apparatus. In some examples, one or more of the method steps of FIG. 8 detailed above may not be performed, or may be performed in a different order.

FIG. 9 shows an example method flow performed by an apparatus. The apparatus may be a communication device. For example, the communication device may be one of: a UE, a terminal, a mobile device, or tablet device.

In S901, the method comprises: receiving, from a network node, a configuration including a condition related to switching between UL SRS resource sets to use for an uplink transmission.

In S903, the method comprises: performing at least one measurement on at least one reference signal.

In S905, the method comprises: determining whether the condition has been fulfilled based on the at least one measurement, wherein the condition is based on at least one of: measured values related to power of a first set of reference signals being a threshold value greater than measured values related to power of a second set of reference signals, or a difference between highest measured values related to power of the first set of reference signals and lowest measured values related to power of the first set of reference signals being greater than a threshold difference value.

In S907, the method comprises: based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.

It should be understood that, in some examples, one or more additional method steps are included in the method flow of FIG.9 and are performed by the apparatus. In some examples, one or more of the method steps of FIG. 9 detailed above may not be performed, or may be performed in a different order.

FIG. 10 shows a schematic representation of non-volatile memory media 1000a (e.g. Blu-ray disc (BD), computer disc (CD) or digital versatile disc (DVD)) and 1000b (e.g. flash memory, solid state memory, universal serial bus (USB) memory stick) storing instructions and/or parameters 1002 which when executed by a processor allow the processor to perform one or more of the steps of the methods of FIGS. 7 to 9.

It is noted that while the above describes example embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

The examples may thus vary within the scope of the attached claims. In general, some embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although embodiments are not limited thereto. While various embodiments may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The examples may be implemented by instructions stored in a memory, e.g. computer software, and executable by at least one data processor of the involved entities or by hardware, or by a combination of software and hardware. Further in this regard it should be noted that any procedures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD.

The term "non-transitory", as used herein, is a limitation of the medium itself (i.e. tangible, not a signal) as opposed to a limitation on data storage persistency (e.g. RAM vs 35 ROM).

As used herein, "at least one of the following:<a list of two or more elements>" and "at least one of: <a list of two or more elements>" and similar wording, where the list of two or more elements are joined by "and", or "or", mean at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi core processor architecture, as non-limiting examples.

As used herein, the terms "means for", "means for performing operations including", "means configured to perform operations including", or "means configured to perform" (or similar) may be any means that are suitable for performing the feature(s). The "means" may be configured to perform one or more of the functions and/or method steps previously described. For example, the "means" may include one or more of: at least one processor, at least one memory, transceiver circuitry, antenna circuitry, etc. It should be understood that these are provided as non-limiting examples.

Alternatively, or additionally some examples may be implemented using circuitry. The circuitry may be configured to perform one or more of the functions and/or method steps previously described. That circuitry may be provided in the base station and/or in the communications device.

As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analogue and/or digital circuitry); (b) combinations of hardware circuits and software, such as: (i) a combination of analogue and/or digital hardware circuit(s) with software/firmware and (U) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as the communications device or base station to perform the various functions previously described; and (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to uses of the term "means" in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example integrated device. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in a server, a cellular network device, or other computing or network device. The foregoing description has provided by way of exemplary and non-limiting examples a full and informative description of some embodiments. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings will still fall within the scope as defined in the appended claims.

Claims

Claims: 1. An apparatus comprising: means for receiving, from a network node, a configuration including a condition related to switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; means for performing at least one measurement on at least one reference signal; means for determining whether the condition has been fulfilled based on the at least one measurement; and means for, based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.
2. The apparatus according to claim 1, wherein one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.
3. The apparatus according to any preceding claim, wherein the at least one first UL SRS resource set is associated with at least one antenna panel of the apparatus, and wherein the at least one second UL SRS resource set is associated with at least one further antenna panel of the apparatus.
4. The apparatus according to any preceding claim, wherein the apparatus comprises: means for providing, to the network node, a capability indication of a capability for event-based switching of antenna panels for transmissions using uplink channels.
5. The apparatus according to claim 4, wherein the capability is indicated either as relevant to physical uplink shared channel, PUSCH, or physical uplink control channel, PUCCH, or as a capability for both PUSCH and PUCCH.
6. The apparatus according to any preceding claim, wherein the apparatus comprises: means for receiving, from the network node, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.
7. The apparatus according to claim 6, wherein the apparatus comprises: means for performing the uplink transmission to the network node based on the at least one second UL SRS resource set.
8. The apparatus according to claim 6, wherein the apparatus comprises: means for performing the uplink transmission to the network node based on the at least one second UL SRS resource set, wherein the uplink transmission being performed is a simultaneous multi-panel transmission.
9. The apparatus according to any preceding claim, wherein the means for performing at least one measurement on at least one reference signal comprises: means for performing the at least one measurement on at least one downlink reference signal resource; and means for comparing the at least one measurement to at least one previous measurement, wherein the at least one previous measurement is associated with measurements performed previously on downlink reference signal resources.
10. The apparatus according to any preceding claim, wherein the condition comprises: measured values related to power of a first set of reference signals being a threshold value greater than measured values related to power of a second set of reference signals.
11. The apparatus according to any preceding claim, wherein the condition comprises: a difference between highest measured values related to power of the first set of reference signals and lowest measured values related to power measured of the first set of reference signals being less than a threshold difference value.
12. The apparatus according to any preceding claim, wherein the means for determining whether the condition has been fulfilled based on the at least one measurement comprises: means for determining whether the condition has been fulfilled for a plurality of candidate UL SRS resource sets based on the at least one measurement; and means for selecting the at least one second UL SRS resource set from UL SRS resource sets of the plurality of candidate UL SRS resource sets that had their condition fulfilled, wherein the selecting is based on the at least one measurement.
13. The apparatus according to any preceding claim, wherein the apparatus is a communication device.
14. An apparatus comprising: means for providing, to a communication device, a configuration including a condition related to the communication device switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; and means for receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.
15. The apparatus according to claim 14, wherein the apparatus comprises: means for, based on the request, providing, to the communication device, an indication to switch from the at least one first UL SRS resource set to the at least one second UL SRS resource set for the uplink transmission.
16. The apparatus according to claim 14 or claim 15, wherein one of: the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets; the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a single UL SRS resource 30 set; the at least one first UL SRS resource set comprises a single UL SRS resource set, and the at least one second UL SRS resource set comprises a single UL SRS resource set; or the at least one first UL SRS resource set comprises a plurality of UL SRS resource sets, and the at least one second UL SRS resource set comprises a plurality of UL SRS resource sets.
17. The apparatus according to any of claims 14 to 16, wherein the at least one first UL SRS resource set is associated with at least one antenna panel of the communication device, and wherein the at least one second UL SRS resource set is associated with at least one further antenna panel of the communication device.
18. The apparatus according to any of claims 14 to 17, wherein the apparatus comprises: means for receiving, from the communication device, a capability indication of a capability of the communication device for event-based switching of antenna panels for transmissions using uplink channels.
19. The apparatus according to any of claims 14 to 18, wherein the apparatus comprises: means for receiving, from the communication device, a simultaneous multi-panel transmission based on the at least one second UL SRS resource set.
20. The apparatus according to any of claims 14 to 19, wherein the apparatus comprises: means for transmitting, to the communication device, at least one downlink reference signal.
21. The apparatus according to any of claims 14 to 20, wherein the apparatus is a network 20 node.
22. A method comprising: receiving, from a network node, a configuration including a condition related to switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; performing at least one measurement on at least one reference signal; determining whether the condition has been fulfilled based on the at least one measurement; and based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.
23. A method comprising: providing, to a communication device, a configuration including a condition related to the communication device switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; and receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.
24. A computer program comprising instructions, which when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a network node, a configuration including a condition related to switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; performing at least one measurement on at least one reference signal; determining whether the condition has been fulfilled based on the at least one measurement; and based on the determining, transmitting, to the network node, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.
25. A computer program comprising instructions, which when executed by an apparatus, cause the apparatus to perform at least the following: providing, to a communication device, a configuration including a condition related to the communication device switching between uplink, UL, sounding reference signal, SRS, resource sets to use for an uplink transmission; and receiving, from the communication device, a request related to performing a switch from at least one first UL SRS resource set to at least one second UL SRS resource set to be used for the uplink transmission, wherein the at least one first UL SRS resource set and the at least one second UL SRS resource set are different.