WO2019227316A1

WO2019227316A1 - Sounding reference signal transmission in unlicensed spectrum

Info

Publication number: WO2019227316A1
Application number: PCT/CN2018/088901
Authority: WO
Inventors: Tao Tao; Jianguo Liu; Zhe LUO; Zhuo WU; Gang Shen; Yan Meng
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy
Priority date: 2018-05-29
Filing date: 2018-05-29
Publication date: 2019-12-05
Also published as: CN112369088B; CN112369088A

Abstract

Embodiments of the present disclosure relate to methods, devices and computer readable storage mediums for sounding reference signal (SRS) transmission in unlicensed spectrum. In example embodiments, a method implemented at a terminal device is provided. According to the method, in response to determining that there is a transmission gap in unlicensed spectrum, a configuration is determined for transmitting a SRS to a network device in the transmission gap. The SRS is transmitted to the network device in the transmission gap based on the configuration. Embodiments of the present disclosure enable SRS transmission in a transmission gap (for example, within a self-contained COT), no matter whether an explicit trigger for SRS transmission is provided or not. By occupying the transmission gap with SRS transmission, the transmission opportunities of uplink control information can also be increased.

Description

SOUNDING REFERENCE SIGNAL TRANSMISSION IN UNLICENSED SPECTRUM

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of communications, and in particular, to methods, devices and computer readable storage mediums for sounding reference signal (SRS) transmission in unlicensed spectrum.

BACKGROUND

It is proposed that the concept of self-contained Channel Occupancy Time (COT) or self-contained transmission opportunity (TXOP) can be utilized in unlicensed spectrum in the fifth generation (5G) New Radio (NR) , so as to improve system performance. A TXOP or COT may include a plurality of slots or sub-frames. In a self-contained TXOP or COT, Hybrid Automatic Repeat Request (HARQ) feedback for data received via one or more slots of the TXOP or COT can be transmitted within the same TXOP or COT. For example, in a self-contained slot, Hybrid Automatic Repeat Request-Acknowledgement (HARQ-ACK) feedback for a Physical Downlink Shared Channel (PDSCH) of a slot may be provided at the end (for example, a last symbol or last few symbols) of the same slot. If all of HARQ feedback can be transmitted in the same COT as their associated PDSCHs, the latency jitter and system complexity can be minimized.

However, the self-contained COT imposes an aggressive requirement on processing capacities of a terminal device. Although the processing capacities of a terminal device have been greatly improved in 5G NR, there may still be a transmission gap (for example, at least two symbols) between an end of a PDSCH and the earliest start of HARQ feedback for the PDSCH within the self-contained COT. Such transmission gap within the self-contained COT may introduce a risk in unlicensed spectrum, since channel access may be lost if other devices are also contending for the channel access. Therefore, it is desired to minimize such transmission gap within the self-contained COT.

SUMMARY

In general, example embodiments of the present disclosure provide methods, devices and computer readable storage mediums for SRS transmission in unlicensed spectrum.

In a first aspect, there is provided a method implemented at a terminal device. According to the method, in response to determining that there is a transmission gap in unlicensed spectrum, a configuration is determined for transmitting a SRS to a network device in the transmission gap. The SRS is transmitted to the network device in the transmission gap based on the configuration.

In a second aspect, there is provided a method implemented at a network device. According to the method, in response to determining that there is a transmission gap in unlicensed spectrum, a configuration is determined for receiving a SRS from a terminal device in the transmission gap. The SRS is receiving from the terminal device in the transmission gap based on the configuration.

In a third aspect, there is provided a device. The device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the device to performs actions. The actions comprise: in response to determining that there is a transmission gap in unlicensed spectrum, determining a configuration for transmitting a SRS to a network device in the transmission gap; and transmitting, based on the configuration, the SRS to the network device in the transmission gap.

In a fourth aspect, there is provided a device. The device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the device to performs actions. The actions comprise: in response to determining that there is a transmission gap in unlicensed spectrum, determining a configuration for receiving a SRS from a terminal device in the transmission gap; and receiving, based on the configuration, the SRS from the terminal device in the transmission gap.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the first aspect of the present disclosure.

In a sixth aspect, there is provided a computer readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the second aspect of the present disclosure.

It is to be understood that this Summary is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

Fig. 1 illustrates an example of a self-contained COT;

Fig. 2 is a block diagram of a communication environment in which embodiments of the present disclosure can be implemented;

Fig. 3 illustrates a flowchart of an example method for transmitting a SRS according to some embodiments of the present disclosure;

Fig. 4 illustrates an example of frequency domain resource allocation for SRS transmission according to some embodiments of the present disclosure;

Fig. 5 illustrates a flowchart of an example method for receiving a SRS according to some embodiments of the present disclosure; and

Fig. 6 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term “communication network” refers to a network that follows any suitable communication standards or protocols such as long term evolution (LTE) , LTE-Advanced (LTE-A) and the fifth generation (5G) New Radio (NR) , and employs any suitable communication technologies, including, for example, Multiple-Input Multiple-Output (MIMO) , OFDM, time division multiplexing (TDM) , frequency division multiplexing (FDM) , code division multiplexing (CDM) , Bluetooth, ZigBee, machine type communication (MTC) , eMBB, mMTC and uRLLC technologies. For the purpose of discussion, in some embodiments, the LTE network, the LTE-A network, the 5G NR network or any combination thereof is taken as an example of the communication network.

As used herein, the term “network device” refers to any suitable device at a network side of a communication network. The network device may include any suitable device in an access network of the communication network, for example, including a base station (BS) , a relay, an access point (AP) , a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a gigabit NodeB (gNB) , a Remote Radio Module (RRU) , a radio header (RH) , a remote radio head (RRH) , a low power node such as a femto, a pico, and the like. For the purpose of discussion, in some embodiments, the eNB is taken as an example of the network device.

The network device may also include any suitable device in a core network, for example, including multi-standard radio (MSR) radio equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs) , Multi-cell/multicast Coordination Entities (MCEs) , Mobile Switching Centers (MSCs) and MMEs, Operation and Management (O&M) nodes, Operation Support System (OSS) nodes, Self-Organization Network (SON) nodes, positioning nodes, such as Enhanced Serving Mobile Location Centers (E-SMLCs) , and/or Mobile Data Terminals (MDTs) .

As used herein, the term “terminal device” refers to a device capable of, configured for, arranged for, and/or operable for communications with a network device or a further terminal device in a communication network. The communications may involve transmitting and/or receiving wireless signals using electromagnetic signals, radio waves, infrared signals, and/or other types of signals suitable for conveying information over air. In some embodiments, the terminal device may be configured to transmit and/or receive information without direct human interaction. For example, the terminal device may transmit information to the network device on predetermined schedules, when triggered by an internal or external event, or in response to requests from the network side.

Examples of the terminal device include, but are not limited to, user equipment (UE) such as smart phones, wireless-enabled tablet computers, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , and/or wireless customer-premises equipment (CPE) . For the purpose of discussion, in the following, some embodiments will be described with reference to UEs as examples of the terminal devices, and the terms “terminal device” and “user equipment” (UE) may be used interchangeably in the context of the present disclosure.

As used herein, the term “cell” refers to an area covered by radio signals transmitted by a network device. The terminal device within the cell may be served by the network device and access the communication network via the network device.

As used herein, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) : (i) a combination of analog and/or digital hardware circuit (s) with software/firmware and (ii) 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 a mobile phone or server, to perform various functions) 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 all uses of this term 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 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 server, a cellular network device, or other computing or network device.

As used herein, the singular forms “a” , “an” , and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to” . The term “based on” is to be read as “based at least in part on” . The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment” . The term “another embodiment” is to be read as “at least one other embodiment” . Other definitions, explicit and implicit, may be included below.

As described above, one of the major motivations of using the self-contained COT in unlicensed spectrum is to transmit HARQ-ACK feedback in the same COT as the associated PDSCH. However, the self-contained COT imposes an aggressive requirement on processing capacities of a terminal device. Although the processing capacities of a terminal device have been greatly improved in 5G NR, there may still be at least two-symbol gap between an end of a PDSCH and the earliest start of HARQ feedback for the PDSCH within the self-contained COT.

Fig. 1 illustrates an example of a self-contained COT. Fig. 1 shows a self-contained COT 100 including four slots 110-1, 110-2, 110-3 and 110-4 (collectively referred to as slot (s) 110) , each of which includes 14 symbols. The slots 110-1, 110-2 and 110-3 are downlink-only slots, while the slot 110-4 is a bi-directional slot. The 0 ^th to 2 ^nd symbols in the slot 110-4 are used for Physical Downlink Control Channel (PDCCH) transmission. The 3 ^rd to 8 ^th symbols in the slot 110-4 are used for PDSCH transmission. However, the 12 ^th and 13 ^th symbols in the slot 110-4 are used to transmit uplink control information (such as, HARQ feedback for PDSCHs transmitted in the slots 110) .

As shown in Fig. 1, there is a transmission gap 120 (that is, the 9 ^th to 11 ^th symbols in the slot 110-4) between the end ofa PDSCH (that is, the 8 ^th symbol in the slot 110-4) and the earliest start of the HARQ feedback (that is, the 12 ^th symbol in the slot 110-4) . The transmission gap 120 within the self-contained COT 100 as shown in Fig. 1 may be very risky in unlicensed spectrum, since channel access may be lost if other devices are also contending for the channel access. Therefore, it is desired to minimize such transmission gap within the self-contained COT.

Embodiments of the present disclosure provide a scheme for filling the above transmission gap within the self-contained COT. The basic idea is to transmit a Sounding Reference Signal (SRS) in the transmission gap. When the gap within the self-contained COT is not too large (for example, not exceeding 4 Orthogonal Frequency Division Multiplexing (OFDM) symbols) , SRS may be a good candidate to be transmitted, since NR has already supported SRS duration of 1, 2 and 4 symbols.

Such additional SRS transmission opportunity can achieve many advantages. For example, a network device (such as, a gNB) can trigger aperiodic SRS transmission in a less frequent manner. The SRS can have high transmission possibility within the shared COT initiated by the network device. Further, more frequent and reliable SRS transmission can result in better uplink channel quality evaluation, finer timing advance estimation, and more reliable beam management.

The inventor has recognized that there may be some bottlenecks to be faced for supporting SRS transmission in the gap of the self-contained COT. For example, the gap between an end of a PDSCH and a start of a Physical Uplink Control Channel (PUCCH) may vary depending on processing time of the terminal device. SRS transmission from different terminal devices may collide in case of no dynamic resource configuration for such SRS transmission. Therefore, the major challenge is how to trigger the SRS transmission and configure a SRS resource dynamically.

It is known that a SRS resource can be configured via Radio Resource Control (RRC) signaling in NR. The configuration on a SRS resource may include an antenna port, consecutive OFDM symbols, a starting position in time and frequency domain, a bandwidth, a cyclic shift for SRS transmission, and so on. Three types of resource configurations are supported for SRS transmission in NR.

One of the three types is used for periodic SRS transmission. When a higher layer parameter “SRS-ResourceConfigType” is set to ‘periodic’ , the terminal device shall transmit the SRS on the SRS resource configured via higher layer signaling. Another one of the three types is used for semi-persistent SRS transmission. When the higher layer parameter “SRS-ResourceConfigType” is set to ‘semi-persistent’ , the SRS transmission will be activated by a higher layer command, and deactivated by another higher layer command. If the terminal device receives the command for activating the SRS transmission, the terminal device shall transmit the SRS on the SRS resource configured via higher layer signaling. The rest one of the three types is used for aperiodic SRS transmission. When the higher layer parameter “SRS-ResourceConfigType” is set to ‘aperiodic’ , the SRS transmission will be triggered by downlink or uplink control information. The control information may include a field which can be used to select at least one SRS resource out of the configured SRS resource set.

It can be seen that, in NR, a SRS resource can only be configured via higher layer signaling. Dynamic configuration of a SRS resource is not supported in NR at present. This means that the current mechanism for SRS transmission in NR cannot support SRS transmission in the gap within the self-contained COT.

Embodiments of the present disclosure provide a solution for SRS transmission in unlicensed spectrum. With the solution, the terminal device can autonomously determine the SRS resource configuration and then perform the SRS transmission accordingly, no matter whether it receives an explicit trigger for SRS transmission or not.

Principles and several embodiments of the present disclosure will be described in detail below with reference to figures.

Fig. 2 shows an example communication network 200 in which embodiments of the present disclosure can be implemented. The network 200 includes a network device 210 and three terminal devices 220-1 and 220-3 (collectively referred to as terminal devices 220 or individually referred to as terminal device 220) served by the network device 210. The coverage of the network device 210 is also called as a cell 202. It is to be understood that the number of base stations and terminal devices is only for the purpose of illustration without suggesting any limitations. The network 200 may include any suitable number of base stations and the terminal devices adapted for implementing embodiments of the present disclosure. Although not shown, it would be appreciated that there may be one or more neighboring cells adjacent to the cell 202 where one or more corresponding network devices provides service for a number of terminal device located therein.

In the communication network 200, the network device 210 can communicate data and control information to the terminal device 220 and the terminal device 220 can also communication data and control information to the network device 210. A link from the network device 210 to the terminal device 220 is referred to as a downlink (DL) , while a link from the terminal device 220 to the network device 210 is referred to as an uplink (UL) .

The communications in the network 200 may conform to any suitable standards including, but not limited to, Global System for Mobile Communications (GSM) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , GSM EDGE Radio Access Network (GERAN) , and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols.

In addition to normal data communications, the network device 210 may send a RS to the terminal device 220 in a downlink. Similarly, the terminal device 220 may transmit a RS to the network device 210 in an uplink. Generally speaking, a RS is a signal sequence (also referred to as “RS sequence” ) that is known by both the network device 210 and the terminal device 220. For example, an uplink RS may be generated and transmitted by the terminal device 220 based on a certain rule and the network device 210 may deduce the RS based on the same rule. Examples of the RS may include but are not limited to downlink or uplink Demodulation Reference Signal (DMRS) , Channel State Information-Reference Signal (CSI-RS) , Sounding Reference Signal (SRS) , Phase Tracking Reference Signal (PTRS) , Tracking Reference Signal (TRS) , fine time-frequency Tracking Reference Signal (TRS) and so on.

In order to transmit a downlink or uplink RS, a corresponding resource (also referred to as “RS resource” ) can be allocated for the transmission. In some scenarios, both the network device 210 and the terminal device 220 are equipped with multiple antenna ports (or antenna elements) and can transmit specified RS sequences with the antenna ports (antenna elements) . As used herein, a RS resource may be referred to one or more resource elements allocated for RS transmission in time, frequency, and/or code domains.

In the communication network 200, the terminal device 220 can transmit a SRS autonomously to the network device 210, no matter whether it receives an explicit trigger for transmission of the SRS or not. For example, the terminal device 220 can perform the SRS transmission when it finds a transmission gap in unlicensed spectrum. Specifically, the terminal device 220 can autonomously determine the SRS resource configuration and then perform the SRS transmission accordingly.

Fig. 3 illustrates a flowchart of an example method 300 for transmitting a SRS according to some embodiments of the present disclosure. The method 300 can be implemented at the terminal device 220 as shown in Fig. 1. For the purpose of discussion, the method 300 will be described from the perspective of the terminal device 220 with reference to Fig. 1. It is to be understood that the method 300 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 310, the terminal device 220 determines whether there is a transmission gap in unlicensed spectrum.

In some embodiments, the transmission gap may be existed prior to a start of an uplink channel. For example, the uplink channel can be any of PUCCH, Physical Uplink Shared Channel (PUSCH) and so on. In this case, for example, the terminal device 220 may determine the existence of the transmission gap at least based on a configuration about the uplink channel from the network device 210.

Alternatively, or in addition, in some embodiments, the transmission gap may be existed between an end of a downlink channel and a start of an uplink channel in a COT. For example, the transmission gap may be between an end of a PDSCH and a start of a PUCCH in a same self-contained COT as the PDSCH. The terminal device 220 may determine the existence of the transmission gap based on configurations about the downlink channel and the uplink channel from the network device 210.

Only for the purpose of illustration, the transmission gap may be shown within a self-contained COT in unlicensed spectrum in some following examples. It is to be understood that this is merely for the purpose of illustration, without suggesting any limitations to the scope of the present disclosure. In practice, embodiments of the present disclosure are also applicable to any transmission gap in unlicensed spectrum, no matter whether the transmission gap is within a self-contained COT or not.

If the terminal device 220 determines that there is a transmission gap (for example, the transmission gap 120 as shown in Fig. 1) in unlicensed spectrum, the method 300 proceeds to block 320, where the terminal device 220 determines a configuration for transmitting a SRS to the network device 210 in the transmission gap.

In some embodiments, instead of obtaining the configuration via RRC signaling, the terminal device 220 may determine the configuration for transmission of the SRS in an implicit manner. For example, the terminal device 220 may determine at least one resource to be used for transmission of the SRS and then determine the configuration for transmission of the SRS based on the at least one resource.

In some embodiments, the terminal device 220 may determine the at least one resource to be used for transmission of the SRS based on at least one of the following: its processing capability, Downlink Control information (DCI) received from the network device 210, an indication of a PUCCH resource (for example, an Acknowledgement/Negative Acknowledgment (ACK/NACK) resource indicator (ARI) ) received from the network device 210, and so on. The at least one resource for transmission of the SRS may include at least one of a time domain resource, a frequency domain resource and a code domain resource.

In some embodiments, the at least one resource for transmission of the SRS may include a time domain resource. The terminal device 220 may determine the time domain resource by determining at least one of a start position to transmit the SRS in time domain and duration (for example, the number of consecutive OFDM symbols) of transmission of the SRS.

In some embodiments, the terminal device 220 may determine the start position and/or the duration for SRS transmission based on its own processing capability. For example, if the processing time from the end of the PDSCH to the earliest start of the HARQ feedback is 4 OFDM symbols, the terminal device may determine the duration for SRS transmission to be 4 OFDM symbols. In addition, the terminal device 220 may determine the start position of SRS transmission at 4 OFDM symbols prior to the start of the PUCCH for transmitting the HARQ feedback.

Alternatively, or in addition, in some embodiments, when the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT, the terminal device 220 may determine the time domain resource based on a location of the transmission gap in the COT. That is, the terminal device 220 may determine the start position and/or the duration for SRS transmission based on OFDM symbols occupied by the transmission gap.

Alternatively, or in addition, in some embodiments, the terminal device 220 may determine the start position and/or the duration for SRS transmission based on DCI received from the network device 210. For example, the DCI may include a slot format indication (SFI) which indicates that whether an OFDM symbol is uplink, downlink or flexible. The terminal device 220 may determine the start position for SRS transmission at least based on the SFI. In some embodiments, the network device 210 may send an explicit SRS trigger to the terminal device 220 via layer-1 signaling. For example, the network device 210 can use a SRS request field in DCI (for example, with Format 1_1) to trigger SRS transmission in the gap of the self-contained COT. In some embodiments, the terminal device 220 may determine the duration for SRS transmission based on the SRS request field in DCI.

In NR, the SRS request filed usually contains two or three bits, indicating the selected SRS resource set configured via higher layer signaling. In some embodiments, the SRS request filed in DCI can be used to support dynamic SRS transmission in the self-contained COT. For example, this 2-bit information can be used to indicate the duration (for example, the number of consecutive OFDM symbols) for SRS transmission. Table 1 shows an example of the SRS request field according to some embodiments of the present disclosure.

Table 1: Example of the SRS request field

When the terminal device 220 receives DCI including the SRS request filed from the network device 210 and the value of the SRS request field is not ‘00’ , the terminal device 220 can determining the duration for SRS transmission based on the value of the SRS request field. Moreover, the terminal device 220 may further determine the start position of SRS transmission at X OFDM symbols prior to the start of the PUCCH for transmitting the HARQ feedback, where X can be 1, 2 or 4.

In some embodiments, the at least one resource for transmission of the SRS may include a frequency domain resource. The terminal device 220 may determine the frequency domain resource by determining at least one of a location of the frequency domain resource in frequency domain and a bandwidth for transmission of the SRS.

In some embodiments, the terminal device 220 may receive an indication of a PUCCH resource from the network device 210. For example, the terminal device 220 may receive an ACK/NACK resource indicator (ARI) from the network device 210. The terminal device 220 may determine the PUCCH resource based on the ARI, and further determine the frequency domain resource for SRS transmission based on the PUCCH resource.

Fig. 4 illustrates an example of frequency domain resource allocation for SRS transmission according to some embodiments of the present disclosure. In the example as shown in Fig. 4, the bandwidth of the unlicensed spectrum may be divided into a plurality of consecutive physical resource blocks (PRBs) . These PRBs may be further divided into a plurality of interlaces, each of which includes several full or partial PRBs separated by a same interval. It is supposed herein that a frequency domain resource for SRS transmission may be allocated in units of PRBs or interlaces. It is to be understood that this is merely for the purpose of illustration, without suggesting any limitations to the present disclosure. In some other embodiments, the frequency domain resource can be allocated in different units.

As shown in Fig. 4, a self-contained COT 400 includes two slots 410-1 and 410-2, each of which includes 14 symbols. The slot 410-1 is a downlink-only slot, while the slot 410-2 is a bi-directional slot. The 0 ^th to 1 ^st symbols in the slot 410-2 are used for PDCCH transmission. The 2 ^nd to 7 ^th symbols in the slot 410-2 are used for PDSCH transmission. The 8 ^th symbol in the slot 410-2 is used for DL-UL switching and timing advance (TA) adjustment. The 9 ^th to 12 ^th symbols in the slot 410-2 are used for SRS transmission, and the 13 ^th symbol in the slot 410-2 is used for PUCCH transmission (for example, transmission of HARQ feedback for PDSCHs transmitted in the slots 410-1 and 410-2) .

In some embodiments, if one or more full interlaces are configured as the PUCCH resource for transmitting the HARQ feedback, the frequency domain resource for SRS transmission may be located in the same interlaces as the PUCCH resource. For example, as shown in Fig. 4, an interlace 420 is allocated to the terminal device 220-1 for PUCCH transmission. In this case, the terminal device 220-1 may determine the interlace 420 as the frequency domain resource for SRS transmission. In addition, the terminal device 220-1 may further determine the bandwidth for SRS transmission based on the bandwidth of the interlace 420.

In some embodiments, if part of a full interlace is configured as the PUCCH resource for transmitting the HARQ feedback, the frequency domain resource for SRS transmission may be located in the same part of the interlace as the PUCCH resource. For example, one interlace may be shared by a plurality of terminal devices. In this event, code domain multiplexing can be utilized to avoid the collision from the plurality of terminal devices in the same interlace. For example, as shown in Fig. 4, an interlace 430 may be shared by the terminal devices 220-2 and 220-3 for transmitting HARQ feedback, each of them may occupy a respective part of PRBs in the interlace 430. In this case, both of the terminal devices 220-2 and 220-3 may perform SRS transmission in the interlace 430, but with different cyclic shifts.

In some embodiments, the at least one resource for transmission of the SRS may include a code domain resource. The terminal device 220 may determine the code domain resource by determining a cyclic shift to be used for transmission of the SRS. In some embodiments, the terminal device 220 may receive an indication of a PUCCH resource from the network device 210. For example, the terminal device 220 may receive an ACK/NACK resource indicator (ARI) from the network device 210. The terminal device 220 may determine the PUCCH resource based on the ARI, and further determine the cyclic shift to be used for transmission of the SRS based on the PUCCH resource.

In some embodiments, a mapping function may be predetermined based on a dependency between the cyclic shift to be used for transmission of the SRS and a start position of the PUCCH resource or the ACK/NACK resource in frequency domain. The terminal device 220 may determine the cyclic shift to be used for transmission of the SRS based on the predetermined mapping function. For example, an example of the mapping function can be represented as below:

where

represents an index of the cyclic shift to be used for transmission of the SRS,

represent an index of a starting cluster for the PUCCH in an interlace, and

represents the maximum number of clusters for the PUCCH in an interlace.

In this way, the terminal device 220 can autonomously determine the resource configuration for transmission of the SRS in a transmission gap, no matter whether it receives an explicit trigger for SRS transmission or not. Although the transmission gap is shown within the self-contained COT in some examples as described above, it is to be understood that this is merely for the purpose of illustration, without suggesting any limitations to the scope of the present disclosure. In practice, embodiments of the present disclosure are also applicable to any transmission gap in unlicensed spectrum, no matter whether the transmission gap is within a self-contained COT or not.

With reference back to Fig. 3, the method 300 proceeds to block 330, where the terminal device 220 transmits the SRS to the network device 210 in the transmission gap based on the configuration.

In some embodiments, the terminal device 220 may transmit the SRS autonomously without an explicit trigger from the network device 210. For example, when the terminal device 220 is triggered to transmit HARQ feedback at the end of the self-contained COT in short PUCCH and the terminal device 220 finds that there is a gap between the end of PDSCH and the start of short PUCCH, the terminal device 220 can transmit the SRS in the transmission gap.

Alternatively, in some embodiments, the network device 210 may send an explicit SRS trigger to the terminal device 220 via layer-1 signaling. For example, the network device 210 can use a SRS request field in DCI (for example, with Format 1_1) to trigger SRS transmission in the gap of the self-contained COT. In some embodiments, the terminal device 220 may transmit the SRS in response to receiving the explicit SRS trigger from the network device 110.

In this way, the SRS can be transmitted in the transmission gap in unlicensed spectrum, thereby reducing the risk of loss of channel access.

In some embodiments, the mechanism for transmitting a SRS in a transmission gap in unlicensed spectrum can always be enabled. That is, the terminal device 220 can perform the SRS transmission if it finds a transmission gap in unlicensed spectrum. Specifically, the terminal device 220 can autonomously determine the SRS resource configuration and then perform the SRS transmission accordingly.

Alternatively, in some other embodiments, the mechanism for transmitting a SRS in a transmission gap in unlicensed spectrum can be enabled via RRC signaling by the network device 210. For example, the method 300 may be performed in response to the RRC signaling for enabling this mechanism being received from the network device 210. Similarly, this mechanism can also be disabled via RRC signaling from the network device 210. For example, if the terminal device 220 receives the RRC signaling for disabling this mechanism from the network device 210, the terminal device 220 may stop transmitting the SRS in the transmission gap.

In some embodiments, if the mechanism for transmitting a SRS in a transmission gap in unlicensed spectrum is enabled, the network device 110 may receive the SRS in the transmission gap from the terminal device 120 in a corresponding manner to the method 300 as described above.

Fig. 5 illustrates a flowchart of an example method 500 for receiving a SRS according to some embodiments of the present disclosure. The method 500 can be implemented at the network device 210 as shown in Fig. 1. For the purpose of discussion, the method 500 will be described from the perspective of the network device 210 with reference to Fig. 1. It is to be understood that the method 500 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 510, the network device 210 determines whether there is a transmission gap in unlicensed spectrum. In some embodiments, the transmission gap is prior to a start of anuplink channel. In some embodiments, the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT.

If the network device 210 determines that there is a transmission gap (for example, the transmission gap 120 as shown in Fig. 1) in unlicensed spectrum, the method 500 proceeds to block 520, where the network device 210 determines a configuration for receiving a SRS from the terminal device 220 in the transmission gap.

In some embodiments, the network device 210 may determine at least one resource to be used for reception of the SRS. The network device 210 may further determine the configuration based on the at least one resource.

In some embodiments, the network device 210 may determine the at least one resource based on at least one of the following: a processing capability of the terminal device; Downlink Control Information (DCI) transmitted to the terminal device 220; and an indication of a PUCCH resource (for example, an ARI) transmitted to the terminal device 220.

In some embodiments, the at least one resource includes a time domain resource to be used for reception of the SRS. The network device 210 may determine the time domain resource by determining at least one of the following: a start position to receive the SRS in time domain; and duration of reception of the SRS.

In some embodiments, the network device 210 may determine the time domain resource based on a processing capability of the terminal device 220.

In some embodiments, if the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT, the network device 210 may determine the time domain resource based on a location of the transmission gap in the COT.

In some embodiments, the network device 210 may transmit Downlink Control information (DCI) including a trigger for transmission of the SRS to the terminal device 220. The network device 210 may determine the time domain resource based on the trigger for the SRS.

In some embodiments, the at least one resource includes a frequency domain resource to be used for reception of the SRS. The network device may determine the frequency domain resource by determining at least one of the following: a location of the frequency domain resource in frequency domain; and a bandwidth for transmission of the SRS.

In some embodiments, the network device 210 may transmit an indication of a PUCCH resource (for example, an ARI) to the terminal device 220. The network device 210 may determine the frequency domain resource based on the PUCCH resource (for example, an ACK/NACK resource) .

In some embodiments, the at least one resource includes a code domain resource to be used for reception of the SRS. The network device 210 may determine a cyclic shift associated with the code domain resource to be used for reception of the SRS.

In some embodiments, the network device 210 may transmit an indication of a PUCCH resource to the terminal device 220. The network device 210 may determine the cyclic shift based on the PUCCH resource. In some embodiments, a mapping function may be predetermined based on a dependency between the cyclic shift to be used for transmission of the SRS and a start position of the PUCCH resource or the ACK/NACK resource in frequency domain. The network device 210 may determine the cyclic shift to be used for reception of the SRS based on the predetermined mapping function.

At block 530, the network device 210 receives the SRS from the terminal device 210 in the transmission gap based on the configuration.

In some embodiments, the network device 210 may not transmit an explicit trigger for SRS transmission to the terminal device 220. In this case, the terminal device 220 may transmit the SRS autonomously to the network device 210. For example, when the terminal device 220 is triggered to transmit HARQ feedback at the end of the self-contained COT in short PUCCH and the terminal device 220 finds that there is a gap between the end of PDSCH and the start of short PUCCH, the terminal device 220 can transmit the SRS in the transmission gap. Similarly, in this case, when the network device 210 finds that there is a gap between the end of PDSCH and the start of short PUCCH, it may attempt to receive the SRS from the terminal device 220.

In some embodiments, the network device 210 may transmit Downlink Control information (DCI) including a trigger for transmission of the SRS to the terminal device. In response to the DCI being transmitted to the terminal device 220, the network device 210 may receive the SRS from the terminal device 220.

It can be seen that embodiments of the present disclosure provide a solution for transmitting a SRS in unlicensed spectrum. Embodiments of the present disclosure enable SRS transmission in a transmission gap (for example, within a self-contained COT) , no matter whether an explicit trigger for SRS transmission is provided or not. By occupying the transmission gap with SRS transmission, the transmission opportunities of uplink control information can also be increased.

In addition, such additional SRS transmission opportunity can bring additional benefits. For example, a network device (such as, a gNB) can trigger aperiodic SRS transmission in a less frequent manner. The SRS can have high transmission possibility within the shared COT initiated by the network device. Further, more frequent and reliable SRS transmission can result in better uplink channel quality evaluation, finer timing advance estimation, and more reliable beam management.

In some embodiments, an apparatus capable of performing the method 300 (for example, the terminal device 220) may comprise means for performing the respective steps of the method 300. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some embodiments, the apparatus comprises: means for determining, in response to determining that there is a transmission gap in unlicensed spectrum, a configuration for transmitting a Sounding Reference Signal (SRS) to a network device in the transmission gap; and means for transmitting, based on the configuration, the SRS to the network device in the transmission gap.

In some embodiments, the transmission gap is prior to a start of an uplink channel.

In some embodiments, the transmission gap is between an end of a downlink channel and a start of an uplink channel in a Channel Occupancy Time (COT) .

In some embodiments, the means for determining the configuration comprises: means for determining at least one resource to be used for transmission of the SRS; and means for determining the configuration based on the at least one resource.

In some embodiments, the means for determining the at least one resource comprises means for determining the at least one resource based on at least one of the following: a processing capability of the terminal device; Downlink Control Information (DCI) received from the network device; and an indication of a PUCCH resource received from the network device.

In some embodiments, the at least one resource includes a time domain resource to be used for transmission of the SRS. The means for determining the at least one resource comprises means for determining the time domain resource by determining at least one of the following: a start position to transmit the SRS in time domain; and duration of transmission of the SRS.

In some embodiments, the means for determining the time domain resource comprises: means for determining the time domain resource based on a processing capability of the terminal device.

In some embodiments, the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT. The means for determining the time domain resource comprises: means for determining the time domain resource based on a location of the transmission gap in the COT.

In some embodiments, the means for determining the time domain resource comprises: means for determining, in response to receiving Downlink Control information (DCI) including a trigger for transmission of the SRS from the network device, the time domain resource based on the trigger for the SRS.

In some embodiments, the at least one resource includes a frequency domain resource to be used for transmission of the SRS. The means for determining the at least one resource comprises means for determining the frequency domain resource by determining at least one of the following: a location of the frequency domain resource in frequency domain; and a bandwidth for transmission of the SRS.

In some embodiments, the means for determining the frequency domain resource comprises: means for determining, in response to receiving an indication of a PUCCH resource from the network device, the PUCCH resource based on the indication; and means for determining the frequency domain resource based on the PUCCH resource.

In some embodiments, the at least one resource includes a code domain resource to be used for transmission of the SRS. The means for determining the at least one resource comprises: means for determining a cyclic shift associated with the code domain resource to be used for transmission of the SRS.

In some embodiments, the means for determining the cyclic shift comprises: means for determining, in response to receiving an indication of a PUCCH resource from the network device, the PUCCH resource based on the indication; and means for determining the cyclic shift based on the PUCCH resource.

In some embodiments, the means for transmitting the SRS comprises: means for transmitting, in response to receiving Downlink Control information (DCI) including a trigger for transmission of the SRS from the network device, the SRS to the network device.

In some embodiments, an apparatus capable of performing the method 500 (for example, the network device 210) may comprise means for performing the respective steps of the method 500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some embodiments, the apparatus comprises: means for determining, in response to determining that there is a transmission gap in unlicensed spectrum, a configuration for receiving a SRS from a terminal device in the transmission gap; and means for receiving, based on the configuration, the SRS from the terminal device in the transmission gap.

In some embodiments, the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT.

In some embodiments, the means for determining the configuration comprises: means for determining at least one resource to be used for reception of the SRS; and means for determining the configuration based on the at least one resource.

In some embodiments, the means for determining the at least one resource comprises means for determining the at least one resource based on at least one of the following: a processing capability of the terminal device; Downlink Control Information (DCI) transmitted to the terminal device; and an indication of a PUCCH resource transmitted to the terminal device.

In some embodiments, the at least one resource includes a time domain resource to be used for reception of the SRS. The means for determining the at least one resource comprises means for determining the frequency domain resource by determining at least one of the following: a location of the frequency domain resource in frequency domain; and a bandwidth for transmission of the SRS.

In some embodiments, the means for determining the time domain resource comprises: means for transmitting DCI including a trigger for transmission of the SRS to the terminal device; and means for determining the time domain resource based on the trigger for the SRS.

In some embodiments, the at least one resource includes a frequency domain resource to be used for reception of the SRS. The means for determining the at least one resource comprises means for determining the frequency domain resource by determining at least one of the following: a location of the frequency domain resource in frequency domain; and a bandwidth for transmission of the SRS.

In some embodiments, the means for determining the frequency domain resource comprises: means for transmitting an indication of a PUCCH resource to the terminal device; and means for determining the frequency domain resource based on the PUCCH resource.

In some embodiments, the at least one resource includes a code domain resource to be used for reception of the SRS. The means for determining the at least one resource comprises: means for determining a cyclic shift associated with the code domain resource to be used for reception of the SRS.

In some embodiments, the means for determining the cyclic shift comprises: means for transmitting an indication of a PUCCH resource to the terminal device; and means for determining the cyclic shift based on the PUCCH resource.

In some embodiments, the means for transmitting the SRS comprises: means for transmitting Downlink Control information (DCI) including a trigger for transmission of the SRS to the terminal device; and means for receiving, in response to the DCI being transmitted to the terminal device, the SRS from the terminal device.

FIG. 6 is a simplified block diagram of a device 600 that is suitable for implementing embodiments of the present disclosure. The device 600 can be implemented at or as at least a part of the terminal device 220 as shown in Fig. 1.

As shown, the device 600 includes a processor 610, a memory 620 coupled to the processor 610, a suitable transmitter (TX) and receiver (RX) 640 coupled to the processor 610, and a communication interface coupled to the TX/RX 640. The memory 620 stores at least a part of a program 630. The TX/RX 640 is for bidirectional communications. The TX/RX 640 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 630 is assumed to include program instructions that, when executed by the associated processor 610, enable the device 600 to operate in accordance with the implementations of the present disclosure, as discussed herein with reference to Figs. 2 to 5. The implementations herein may be implemented by computer software executable by the processor 610 of the device 600, or by hardware, or by a combination of software and hardware. The processor 610 may be configured to implement various implementations of the present disclosure. Furthermore, a combination of the processor 610 and memory 620 may form processing means 650 adapted to implement various implementations of the present disclosure.

The memory 620 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 620 is shown in the device 600, there may be several physically distinct memory modules in the device 600. The processor 610 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 600 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The components included in the apparatuses and/or devices of the present disclosure may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In one embodiment, one or more units may be implemented using software and/or firmware, for example, machine-executable instructions stored on the storage medium. In addition to or instead of machine-executable instructions, parts or all of the units in the apparatuses and/or devices may be implemented, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs) , Application-specific Integrated Circuits (ASICs) , Application-specific Standard Products (ASSPs) , System-on-a-chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , and the like.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. 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. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method 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 present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the method 300 as described above with reference to Fig. 3 or the method 500 as described above with reference to Fig. 5. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable media.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A method implemented at a terminal device, comprising:

in response to determining that there is a transmission gap in unlicensed spectrum, determining a configuration for transmitting a Sounding Reference Signal (SRS) to a network device in the transmission gap; and

transmitting, based on the configuration, the SRS to the network device in the transmission gap.
The method of claim 1, wherein the transmission gap is prior to a start of an uplink channel.
The method of claim 1, wherein the transmission gap is between an end of a downlink channel and a start of an uplink channel in a Channel Occupancy Time (COT) .
The method of claim 1, wherein determining the configuration comprises:

determining at least one resource to be used for transmission of the SRS; and

determining the configuration based on the at least one resource.
The method of claim 4, wherein determining the at least one resource comprises:

determining the at least one resource based on at least one of the following:

a processing capability of the terminal device;

Downlink Control Information (DCI) received from the network device; and

an indication of a Physical Uplink Control Channel (PUCCH) resource received from the network device.
The method of claim 4, wherein the at least one resource includes a time domain resource to be used for transmission of the SRS, and wherein determining the at least one resource comprises:

determining the time domain resource by determining at least one of the following:

a start position to transmit the SRS in time domain; and

duration of transmission of the SRS.
The method of claim 6, wherein determining the time domain resource comprises:

determining the time domain resource based on a processing capability of the terminal device.
The method of claim 6, wherein the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT, and wherein determining the time domain resource comprises:

determining the time domain resource based on a location of the transmission gap in the COT.
The method of claim 6, wherein determining the time domain resource comprises:

in response to receiving Downlink Control information (DCI) including a trigger for transmission of the SRS from the network device, determining the time domain resource based on the trigger for the SRS.
The method of claim 4, wherein the at least one resource includes a frequency domain resource to be used for transmission of the SRS, and wherein determining the at least one resource comprises:

determining the frequency domain resource by determining at least one of the following:

a location of the frequency domain resource in frequency domain; and

a bandwidth for transmission of the SRS.
The method of claim 10, wherein determining the frequency domain resource comprises:

in response to receiving an indication of a PUCCH resource from the network device, determining the PUCCH resource based on the indication; and

determining the frequency domain resource based on the PUCCH resource.
The method of claim 4, wherein the at least one resource includes a code domain resource to be used for transmission of the SRS, and wherein determining the at least one resource comprises:

determining a cyclic shift associated with the code domain resource to be used for transmission of the SRS.
The method of claim 12, wherein determining the cyclic shift comprises:

in response to receiving an indication of a PUCCH resource from the network device, determining the PUCCH resource based on the indication; and

determining the cyclic shift based on the PUCCH resource.
The method of any of claims 1-13, wherein transmitting the SRS comprises:

in response to receiving Downlink Control information (DCI) including a trigger for transmission of the SRS from the network device, transmitting the SRS to the network device.
A method implemented at a network device, comprising:

in response to determining that there is a transmission gap in unlicensed spectrum, determining a configuration for receiving a Sounding Reference Signal (SRS) from a terminal device in the transmission gap; and

receiving, based on the configuration, the SRS from the terminal device in the transmission gap.
The method of claim 15, wherein the transmission gap is prior to a start of an uplink channel.
The method of claim 15, wherein the transmission gap is between an end of a downlink channel and a start of an uplink channel in a Channel Occupancy Time (COT) .
The method of claim 15, wherein determining the configuration comprises:

determining at least one resource to be used for reception of the SRS; and

determining the configuration based on the at least one resource.
The method of claim 18, wherein determining the at least one resource comprises:

determining the at least one resource based on at least one of the following:

a processing capability of the terminal device;

Downlink Control Information (DCI) transmitted to the terminal device; and

an indication of a Physical Uplink Control Channel (PUCCH) resource transmitted to the terminal device.
The method of claim 18, wherein the at least one resource includes a time domain resource to be used for reception of the SRS, and wherein determining the at least one resource comprises:

determining the time domain resource by determining at least one of the following:

a start position to receive the SRS in time domain; and

duration of reception of the SRS.
The method of claim 20, wherein determining the time domain resource comprises:

determining the time domain resource based on a processing capability of the terminal device.
The method of claim 20, wherein the transmission gap is between an end of a downlink channel and a start of an uplink channel in a COT, and wherein determining the time domain resource comprises:

determining the time domain resource based on a location of the transmission gap in the COT.
The method of claim 20, wherein determining the time domain resource comprises:

transmitting Downlink Control information (DCI) including a trigger for transmission of the SRS to the terminal device; and

determining the time domain resource based on the trigger for the SRS.
The method of claim 18, wherein the at least one resource includes a frequency domain resource to be used for reception of the SRS, and wherein determining the at least one resource comprises:

determining the frequency domain resource by determining at least one of the following:

a location of the frequency domain resource in frequency domain; and

a bandwidth for transmission of the SRS.
The method of claim 24, wherein determining the frequency domain resource comprises:

transmitting an indication of a PUCCH resource to the terminal device; and

determining the frequency domain resource based on the PUCCH resource.
The method of claim 18, wherein the at least one resource includes a code domain resource to be used for reception of the SRS, and wherein determining the at least one resource comprises:

determining a cyclic shift associated with the code domain resource to be used for reception of the SRS.
The method of claim 26, wherein determining the cyclic shift comprises:

transmitting an indication of a PUCCH resource to the terminal device; and

determining the cyclic shift based on the PUCCH resource.
The method of any of claims 15-27, wherein transmitting the SRS comprises:

transmitting Downlink Control information (DCI) including a trigger for transmission of the SRS to the terminal device; and

in response to the DCI being transmitted to the terminal device, receiving the SRS from the terminal device.
A device comprising:

a processor; and

a memory coupled to the processor and having instructions stored thereon, the instructions, when executed by the processor, causing the device to perform the method of any of claims 1 to 14.
A device comprising:

a processor; and

a memory coupled to the processor and having instructions stored thereon, the instructions, when executed by the processor, causing the device to perform the method of any of claims 15 to 28.
A computer readable storage medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method of any of claims 1 to 14.
A computer readable storage medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method of any of claims 15 to 28.