WO2024026734A1

WO2024026734A1 - Long srs sequence support by srs frequency hopping and stitching

Info

Publication number: WO2024026734A1
Application number: PCT/CN2022/109983
Authority: WO
Inventors: Hyun-Su Cha; Ryan Keating; Tao Tao
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy; Nokia Technologies Oy
Priority date: 2022-08-03
Filing date: 2022-08-03
Publication date: 2024-02-08
Also published as: TW202408179A

Abstract

Various example embodiments relate to methods and apparatuses for uplink positioning reference signal transmission. An apparatus may be configured to receive from a network device in a radio access network configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; generate a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and transmit the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.

Description

LONG SRS SEQUENCE SUPPORT BY SRS FREQUENCY HOPPING AND STITCHING

TECHNICAL FIELD

Various example embodiments described herein generally relate to communication technologies, and more particularly, to methods and apparatuses for supporting long SRS sequence by SRS frequency hopping and stitching.

BACKGROUND

Certain abbreviations that may be found in the description and/or in the figures are herewith defined as follows:

BWP Bandwidth Part

CRB Common Resource Block

DL Downlink

gNB next Generation Node-B

LMC Location Management Component

LMF Location Management Function

NR New Radio

NRPPa NR Positioning Protocol A

PRS Positioning Reference Signal

RAN Radio Access Network

RE Resource Element

RedCap Reduced Capability

SRS Sounding Reference Signal

TRP Transmission Reception Point

UE User Equipment

UL Uplink

ZC Zadoff-Chu

Wireless communication systems have developed through various generations, and can support various types of service applications for terminal devices. For some applications, it may be useful to be able to obtain a position of a terminal device through a wireless communication system, so that a large number of position-based services (e.g., emergency calls, navigation assistance, asset tracking, etc. ) can be provided. In some scenarios, it may be desirable to support positioning for a reduced capability (RedCap) terminal device with reduced bandwidth and reduced number of receive RF chains.

SUMMARY

A brief summary of exemplary embodiments is provided below to provide basic understanding of some aspects of various embodiments. It should be noted that this summary is not intended to identify key features of essential elements or define scopes of the embodiments, and its sole purpose is to introduce some concepts in a simplified form as a preamble for a more detailed description provided below.

In a first aspect, an example embodiment of a terminal device in a radio access network is provided. The terminal device may comprise at least one processor and at least one memory. The at least one memory may store instructions that, when executed by the at least one processor, may cause the terminal device at least to receive, from a network device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; generate a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and transmit the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.

In a second aspect, an example embodiment of a network device in a radio access network is provided. The network device may comprise at least one processor and at least one memory. The at least one memory may store instructions that, when executed by the at least one processor, may cause the network device at least to transmit to a terminal device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and receive from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.

In a third aspect, an example embodiment of a location server is provided. The location server may comprise at least one processor and at least one memory. The at least one memory may store instructions that, when executed by the at least one processor, may cause the location server at least to receive, from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and transmit the configuration information to at least one second network device in the radio access network configured to position the terminal device.

Example embodiments of methods, apparatus and computer program products are also provided. Such example embodiments generally correspond to the example embodiments in the above aspects and a repetitive description thereof is omitted here for convenience.

Other features and advantages of the example embodiments of the present disclosure will also be apparent from the following description of specific embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of example embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described, by way of non-limiting examples, with reference to the accompanying drawings.

Fig. 1 illustrates an example wireless communication network in which example embodiments of the present disclosure can be implemented.

Figs. 2A and 2B illustrate examples of frequency hopping and stitching of DL PRS and UL SRS.

Figs. 3A and 3B illustrate examples of conventional sequence mapping of positioning SRS resource.

Fig. 4 is a message flow diagram illustrating a process for frequency hopping and stitching of UL SRS according to an example embodiment of the present disclosure.

Fig. 5 illustrates an example of SRS sequence generation and mapping according to an example embodiment of the present disclosure.

Fig. 6 illustrates an example of SRS sequence generation based on a virtual SRS resource and mapping to the associated SRS resources according to an example embodiment of the present disclosure.

Figs. 7A and 7B illustrate examples of SRS sequence mapping to the overlapping REs between associated SRS resources according to example embodiments of the present disclosure.

Fig. 8 is a message flow diagram illustrating a process for positioning a UE based on a virtual SRS resource configuration according to an example embodiment of the present disclosure.

Fig. 9 is a schematic flowchart illustrating operations for frequency hopping and stitching implemented at a terminal device according to an example embodiment of the present disclosure.

Fig. 10 is a schematic flowchart illustrating operations for frequency hopping and stitching implemented at a network device according to an example embodiment of the present disclosure.

Fig. 11 is a schematic flowchart illustrating operations for frequency hopping and stitching implemented at a location server according to an example embodiment of the present disclosure.

Fig. 12 is a schematic structure block diagram illustrating devices in a communication system in which example embodiments of the present disclosure can be implemented.

Fig. 13 is a schematic functional block diagram illustrating an apparatus according to an example embodiment of the present disclosure.

Fig. 14 is a schematic functional block diagram illustrating an apparatus according to an example embodiment of the present disclosure.

Fig. 15 is a schematic functional block diagram illustrating an apparatus according to an example embodiment of the present disclosure.

Throughout the drawings, same or similar reference numbers indicate same or similar elements. A repetitive description on the same elements would be omitted.

DETAILED DESCRIPTION

Herein below, some example embodiments are described in detail with reference to the accompanying drawings. The following description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known circuits, techniques and components are shown in block diagram form to avoid obscuring the described concepts and features.

As used herein, the term “terminal device” or “user equipment” (UE) refers to any entities or devices that can wirelessly communicate with the network devices or with each other. Examples of the terminal device can include a mobile phone, a mobile terminal (MT) , a mobile station (MS) , a subscriber station (SS) , a portable subscriber station (PSS) , an access terminal (AT) , a computer, a wearable device, an on-vehicle communication device, a machine type communication (MTC) device, a D2D communication device, a V2X communication device, a sensor and the like. The term “terminal device” can be used interchangeably with a UE, a user terminal, a mobile terminal, a mobile station, or a wireless device.

As used herein, the term “network device” refers to any suitable entities or devices that can provide cells or coverage, through which the terminal device can access the network or receive services. The network device may be commonly referred to as a base station. The term “base station” used herein can represent a node B (NodeB or NB) , an evolved node B (eNodeB or eNB) , or a gNB. The base station may be embodied as a macro base station, a relay node, or a low power node such as a pico base station or a femto base station. The base station may consist of several distributed network units, such as a central unit (CU) , one or more distributed units (DUs) , one or more remote radio heads (RRHs) or remote radio units (RRUs) . The number and functions of these distributed units depend on the selected split RAN architecture.

As used herein, the term “network function” (NF) refers to a processing function in a network, and defines a functional behavior and an interface. The network function may be implemented by using dedicated hardware, or may be implemented by running software on dedicated hardware, or may be implemented on a form of a virtual function on a common hardware platform. From a perspective of implementation, network functions may be classified into a physical network function and a virtual network function. From a perspective of use, network functions may be classified into a dedicated network function and a shared network function.

Fig. 1 illustrates a simplified schematic diagram of a cellular communication network 100 in which example embodiments of the present disclosure can be implemented. The cellular communication network 100 may be implemented as a multiple access system capable of supporting communication with multiple users sharing available system resources. The cellular communication network 100 may employ one or more channel access schemes such as Time Division Multiple Access (TDMA) , Code Division Multiple Access (CDMA) , Frequency Division Multiple Access (FDMA) , Orthogonal Frequency Division Multiple Access (OFDMA) , Single Carrier Frequency Division Multiple Access (SC-FDMA) , Single-User Multiple-Input Multiple-Output (SU-MIMO) and Multi-User Multiple-Input Multiple-Output (MU-MIMO) , and the like. These multiple access schemes may be formulated in 4G Long Term Evolution (LTE) , 5G New Radio (NR) , or beyond 5G radio standards. For convenience of description, Fig. 1 shows the cellular communication network 100 as a 5G NR network including a plurality of 5G base stations “gNB” , but it would be appreciated that example embodiments disclosed herein can also be implemented in a 4G LTE network or a beyond 5G network.

Referring to Fig. 1, the communication network 100 may include a user equipment (UE) 110 and a plurality of base stations (shown as gNBs) 120a, 120b, 120c. The plurality of

base stations

120a, 120b, 120c, collectively referred to as base stations 120, may form a so-called radio access network (RAN) and provide network access to a plurality of UEs. For example, the UE 110 may camp in a cell supported by the base station 120a and establish a radio resource control (RRC) connection with the base station 120a. The UE 110 may communicate with the base station 120a on uplink and downlink channels. The base station 120a may be referred to as a serving base station for the UE 110, and the

base stations

120b, 120c may be referred to as neighbor base stations. The UL PRS of Fig. 1 is uplink reference signals used to estimate the location of UE 110 such as sounding reference signal (SRS) .

In some example embodiments, the communication network 100 may employ a multiple transmission reception point (mTRP) architecture where the UE 110 can transmit data to and receive data from one or more transmission reception points (TRPs) . The TRPs may be associated with one or more base stations 120 and/or one more cells. The term “cell” used herein may refer to a particular geographic coverage area served by a base station and/or a subsystem of the base station serving the coverage area, depending on the context in which the term is used. It would be appreciated that when the description herein indicates that a “cell” performs functions, a base station serving the cell would perform the functions. Example embodiments described herein are not limited to any particular deployment of the TRPs or a particular relationship between the TRPs and the base stations/cells. It would also be appreciated that throughout the present disclosure, the term “base station” may also comprise a TRP, and operations performed at a base station may be performed at least partially at a TRP.

With continuous reference to Fig. 1, the communication network 100 may further comprise a location server 130 to manage positioning of UEs connected to the network 100. The location server 130 may be a physical or logical entity which may be implemented as a local location management component (LMC) in a base station or as a location management function (LMF) within a core network. The base stations 120 may connect to the core network through so called backhaul connections.

Various NR positioning aspects were introduced in 3GPP Rel. 16 to enable radio access technology (RAT) based positioning solutions. For example, both downlink (DL) and uplink (UL) positioning reference signal (PRS) are introduced to facilitate positioning measurements for the UE 110. More specifically, a UL positioning method may make use of the UL PRS transmitted by the UE 110 to the serving base station 120a and one or more neighbor base stations such as the

base station

120b, 120c. The

base station

120a, 120b, and 120c may obtain positioning measurements based on the UL PRS and then send a measurement report to the location server 130 for determination of the position of the UE 110. A DL positioning method may make use of DL PRSs transmitted by one or

more base stations

120a, 120b, 120c. The DL PRSs are obtained by the UE 110 to estimate its position. Throughout the present disclosure, the terms “positioning reference signal” and “PRS” may refer to any UL or DL reference signal which can be used to perform positioning measurements. Examples of such UL reference signals may include the sounding reference signal (SRS) , physical random-access channel (PRACH) , UL demodulation reference signal (DMRS) , UL phase tracking reference signal (PTRS) , and any other UL reference signals which can be used for UL positioning as defined in 3GPP specifications. Hereinafter, for convenience of explanation, a description is made with respect to SRS, although the features of the present disclosure are also applicable to other UL reference signals.

As noted above, various categories of UEs can be supported in the communication network 100. For example, a number of UEs are allocated to a new UE category denoted as reduced capability (RedCap) UEs starting from Rel. 17. Examples of the RedCap UEs may include wearable devices, industrial sensors, surveillance cameras, and the like. Generally, the RedCap UEs are characterized in having reduced bandwidth support and reduced complexity including the number of receive radio frequency (RF) chains compared with normal UEs. For example, the RedCap UEs may have a maximum bandwidth of 20 MHz for Frequency Range 1 in Rel. 17, which may be further reduced to e.g. 5 MHz in Rel. 18.

An important indicator for measuring positioning performance is positioning accuracy. In Rel. 16, the positioning accuracy is targeted to be less than 3 m, and it was enhanced in Rel. 17 with target accuracy of less than 30 cm. The frequency bandwidth resource is the critical factor to the positioning accuracy. To overcome performance degradation due to the narrow bandwidth of the PRS resource allocated to the RedCap UEs so as to meet the positioning requirements, a typical way would be frequency hopping and stitching. One SRS frequency hop may be a part or full of the bandwidth of an SRS that UE can transmit at once. One SRS frequency hop may be defined in one UL BWP if the base station combines received SRSs transmitted by multiple UL BWPs.

Figs. 2A and 2B illustrate examples of frequency hopping and stitching of DL PRS and UL SRS respectively. As shown in Fig. 2A, the LMF 130 may configure wideband DL PRS resources for the UE 110, and the UE 110 may receive a different part of them at each measurement occasion. Then the UE 110 may stitch the measurements (Measurement #1, Measurement #2, and Measurement #3) measured across multiple PRS measurement occasions. As a result, the UE 110 could receive the wideband PRS.

However, support of the UL frequency hopping and stitching is different than that of the DL case. Referring to Fig. 2B, in case of UL frequency hopping and stitching, the UE 110 may be configured with multiple SRS (SRS resource #1, SRS resource #2, and SRS resource #3) with an appropriate time gap therebetween for BWP switching. The UE 110 may transmit the narrow band SRSs across multiple frequency hops in the whole bandwidth. The narrow band SRS at each frequency hop would be the maximum bandwidth of an activated UL BWP. As the transmitted SRS sequence at each hop is generated separately, the base station 120 will see independent and multiple sequence set by combining the SRS measurements. That is to say, the combined received signal is not a single ZC sequence.

Figs. 3A and 3B illustrate examples of conventional sequence mapping of SRS resource for positioning. Under current 3GPP specification, an SRS is transmitted on every Nth subcarrier where N denotes a comb size which can take a value of two, four, eight or other values, and the same sequence elements are allocated to resource elements (REs) across multiple symbols with different comb-offset. For example, in case of an SRS resource with comb-2 and 2-symbol as shown in Fig. 3A, the same sequence elements are allocated to REs across two symbols with different comb-offset. As a result, the same sequence element is repeated two times in the frequency domain in the combined received signal 200a. Similarly, referring to Fig. 3B, for an SRS resource with comb-4 and 4-symbol, the same sequence elements are allocated to four symbols with different comb-offset, and the same sequence element is repeated four times in the frequency domain in the combined received signal 200b.

The sequence mapping rules shown in Figs. 3A and 3B are unsuitable for SRS frequency hopping and stitching. As discussed above, the sequence length is different depending on the comb-size, and the sequence length is short for high comb-size given a preset bandwidth. If two different SRS resources have different comb-size and number of symbols, it is difficult to allocate the same sequence element to the overlapping resource blocks (RBs) for frequency hopping and stitching operation. Furthermore, the combined signal is not a single ZC sequence.

Therefore, it is desirable to provide an efficient mechanism to support long SRS sequence by frequency hopping and stitching to be used for positioning of RedCap UEs, for example.

Hereinafter, example embodiments of methods and apparatuses supporting long SRS sequence by frequency hopping and stitching would be described in detail with reference to the drawings. In the example embodiments, a single long ZC sequence may be used for SRS frequency hopping and stitching. The example embodiments allow bandwidth limited UEs (e.g., RedCap UEs) to achieve full or wide bandwidth by frequency hopping. Thus, the positioning performance can be improved.

Fig. 4 is a message flow diagram illustrating a process for frequency hopping and stitching of uplink SRS according to an example embodiment of the present disclosure. The process shown in Fig. 4 may be performed by a base station and a user equipment. For example, the UE 110 and the serving base station 120a in the communication network 100 described above with reference to Fig. 1 may be configured to perform the frequency hopping and stitching process. The UE 110 and the serving base stations 120a each may include a plurality of components, modules, means or elements to perform operations discussed below, and the components, modules, means and elements may be implemented in various manners including but not limited to for example software, hardware, firmware or any combination thereof to perform the operations.

Referring to Fig. 4, at an operation 310, the serving base station 120a may transmit an SRS resource configuration to the UE 110, e.g., via an RRC message. The base station 120a may configure the UE 110 with multiple SRS resources. For example, the multiple SRS resources may be configured for UL channel estimation, positioning, or a multiple input multiple output (MIMO) related operation, etc.

In an example embodiment, the configuration for the SRS resource may comprise at least one of time duration, transmission bandwidth, comb size, cyclic shift, transmission beam information of the SRS, or the like. The base station 120a may determine one or more parameters of the SRS resource configuration based on capability information of the UE 110, as well as other information such as a positioning requirement (e.g., positioning accuracy) of the UE 110. The capability information may indicate the capability of the UE 110 to perform SRS frequency hopping and stitching operation. For example, the capability information may include, but not limited to, device category (normal UE or RedCap UE) , maximum transmission bandwidth, number of antennas, or the like. In an example, the UE 110 may report the capability information to the base station 120a in advance or in response to receiving a request from the base station 120a. Based on the received capability information, the base station 120a may configure and allocate a plurality of SRS resources that fall within the maximum transmission bandwidth of the UE 110. For example, each SRS resource may be configured with a specific UL bandwidth part (BWP) . In an example, to facilitate SRS frequency hopping, two successive SRS resources of the configured SRS resources may partially overlap with each other in the frequency domain.

At an operation 312, the base station 120a may transmit, and the UE 110 may receive configuration information for determining the SRS transmission. In an example, the configuration information may indicate a virtual SRS resource associated with a plurality of SRS resources allocated to the UE 110. By the term “virtual SRS resource” is meant the SRS resource does not occupy actual physical resource but is a logical resource to be mapped to multiple actual physical SRS resources. The virtual SRS resource may be deemed as an aggregation of a plurality of physical SRS resources allocated to the UE 110. With the virtual SRS resource, a single long ZC sequence may be transmitted through the plurality of SRS resources by SRS frequency hopping and stitching, so that more accurate positioning of the UE 110 can be achieved.

For example, the configuration information may include association information between the virtual SRS resource and the plurality of SRS resources. As discussed above, the plurality of SRS resources may be SRS resource for various purposes, e.g., uplink channel state estimation, positioning, or a MIMO related operation such as transmit or receive beamforming. In an example, the association information may indicate that the plurality of SRS resources are configured for SRS frequency hopping and stitching. In other words, if the association information is configured, the UE 110 may understand that the base station 120a allocates the associated plurality of SRS resources for SRS frequency hopping and stitching operation.

Fig. 5 illustrates an example of association between a virtual SRS resource and multiple SRS resources. As shown in Fig. 5, the base station 120a may configure multiple SRS resources for the UE 110, e.g., a first SRS resource 410, a second SRS resource 420, and a third SRS resource 430. The first SRS resource 410, second SRS resource 420, and third SRS resource 430 are associated with a respective BWP. In an example, the configured

SRS resources

410, 420, 430 may be located in different uplink BWPs so that UL positioning measurement for a wide or full bandwidth may be achieved by performing frequency hopping. Further, the base station 120a may configure a virtual SRS resource 400 and associate it to the configured

SRS resources

410, 420, and 430. Upon receiving the association information, the UE 110 may understand that the

SRS resources

410, 420, 430 are allocated for frequency hopping and stitching operation in positioning, and the UE 110 may proceed to generate and transmit the SRS sequence, which will be described in more detail later. Note that, although three SRS resources are shown in Fig. 5, the base station 120a can configure more or less SRS resources for the UE 110.

In an example embodiment, the configuration information may include other information associated with the virtual SRS resource. For example, the information may indicate at least one of validation time of association between the virtual SRS resource (e.g., virtual SRS resource 400) and the plurality of SRS resources (e.g.,

SRS resources

410, 420, 430) , spatial relation information indicative of one or more beams for the plurality of SRS resources associated with the virtual SRS resource, or sequence generation and mapping information for generating the SRS sequence and mapping the SRS sequence to the plurality of SRS resources.

In an example, the virtual SRS resource will only apply for the time period indicated in the validation time information. In other words, the virtual SRS resource configuration may be turned off after the validation time lapses, and the configured SRS resources (e.g.,

SRS resources

410, 420, and 430) may be used by the UE 110 for other purposes. In another example, the validation time is set as default to the duration of the associated SRS resources. For example, if the associated SRS resources are semi-persistent and deactivated at some time, the virtual SRS resource is also deactivated at that time.

The spatial relation information may indicate the transmission beam information for the plurality of SRS resources. If the spatial relation information is configured, the UE 110 may follow this new configured spatial relation information and ignore or override the spatial relation information previously configured for each SRS resource. In an example, the UE 110 may be configured with the same spatial relation information for the associated SRS resources. For example, the UE 110 may transmit the SRSs carried on the respective SRS resources by using the same beam width.

The base station 120a may configure sequence generation and mapping information in the configuration information for instructing the UE 110 to generate the SRS sequence and map the SRS sequence to the plurality of SRS resources. For example, the sequence generation information may include sequence length, sequence ID, or the like for the UE 110 to determine the ZC sequence. The mapping information may include parameters such as comb-size, cyclic shift, sequence element to RE mapping, or the like. Similar to the validation time and the spatial relation information, the new configured sequence generation and mapping information may override corresponding configuration for the plurality of SRS resources. For example, if SRS parameters such as comb-size, cyclic shift are configured in the sequence generation and mapping information, the UE 110 may follow the new configured comb-size and/or cyclic shift within the validation time and ignore the comb-size and cyclic shift previously configured for the SRS resources.

Referring back to Fig. 4, at an operation 314, based on the received configuration information, the UE 110 may generate an SRS sequence corresponding to the virtual SRS resource so that the SRS sequence is a complete single sequence, e.g., a ZC sequence. Then at an operation 316, the UE 110 may map the SRS sequence to the plurality of SRS resources. In an example embodiment, the UE 110 may generate and map the SRS sequence based on a preset generation and mapping rule. Alternatively, if the base station 120a configures sequence generation and mapping information in the configuration information, the UE 110 would follow the new configured information to perform the

operations

314, 316.

By way of example, referring to Fig. 5, for the virtual SRS resource 400, the UE 110 may generate a length-M ZC sequence 440 composed of M sequence elements denoted as c (0) , c (1) , …, c (M) . The total sequence length M may be determined based on the number of subcarriers of the

SRS resources

410, 420, 430 associated to the virtual SRS resource 400. In an example, the sequence length M can be determined by a sum of the number of subcarriers in the plurality of SRS resources minus the number of overlapping subcarriers between the plurality of SRS resources.

After the SRS sequence 440 is generated for the virtual SRS resource 400, the UE 110 may map the SRS sequence 440 to the

SRS resources

410, 420, and 430, e.g., based on the mapping information in the configuration information. For example, a sequence element in the SRS sequence 440 may be mapped to one subcarrier among the plurality of SRS resources in the frequency domain. Referring to Fig. 5, the sequence elements c (0) , c (1) , …, c (k’+L) of the SRS sequence 440 may be mapped to the physical resource elements (REs) of the first configured SRS resource 410. Similarly, the sequence elements c (k’) , c (k’+1) , …, c (k’+L’) of the SRS sequence 440 may be mapped to the REs of the SRS resource 420, and the sequence elements c (k’+m) , …, c (M) of the SRS sequence 440 may be mapped to the REs of the SRS resource 430. In other words, the

SRS resources

410, 420, 430 may convey different parts of the SRS sequence 440, and these different parts may partly overlap.

In an example embodiment, when two SRS resources of the plurality of

SRS resources

410, 420, and 430 have overlapping BWPs, resource blocks (RBs) , or subcarriers, the corresponding two parts of the SRS sequence 440 mapped to the two SRS resources may include a same sequence section mapped to the overlapping subcarriers. As shown in Fig. 5, the sequence elements c (k’) , c (k’+1) , …, c (k’+L) are mapped to both SRS resource 410 and SRS resource 420 in the overlapping subcarriers. Also, the sequence elements c (k’+m) , …, c (k’+L’) are mapped to both SRS resource 420 and SRS resource 430 in the overlapping subcarriers. In this way, the base station 120a could see a single complete ZC sequence across the three SRS resource BWPs.

As discussed above, the SRS sequence generation and mapping rule of the present disclosure is different than that the current rule described above with reference to Figs. 3A-3B. Other aspects of the generation and mapping rule will be described in greater detail with respect to Figs. 6-7.

Fig. 6 illustrates an example of SRS sequence generation based on a virtual SRS resource and mapping to the associated SRS resources according to an example embodiment of the present disclosure. Referring to Fig. 6, a first SRS resource 510 and a second SRS resource 520 may be configured for the UE 110 for frequency hopping. The first SRS resource 510 is configured with a comb-2 structure, which comprises 24 subcarriers in the frequency domain and spans two consecutive symbols in the time domain. The second SRS resource 520 is configured with a comb-4 structure, which also comprise 24 subcarriers in the frequency domain but spans four consecutive symbols in the time domain. As shown, the first SRS resource 510 and the second SRS resource 520 overlap partly in the frequency domain.

When the UE 110 is configured by the base station 120a with a virtual SRS resource 500 associated with the two

SRS resources

510, 520, the UE 110 may first determine a length of the SRS sequence corresponding to the virtual SRS resource 500. In the case shown in Fig, 6, the sequence length may be determined to be 36, calculated based on the sum of subcarriers of the two SRS resources minus the number of overlapping subcarriers between the two SRS resources. Based on the determined sequence length, the UE 110 may accordingly generate a length-36 SRS sequence (e.g., ZC sequence) .

Then, the UE 110 may map the generated SRS sequence composed of 36 sequence elements, i.e., c (0) , c (1) , …, c (35) , to the first SRS resource 510 and the second SRS resource 520. As shown in Fig. 6, except for the overlapping subcarriers between the two SRS resources, a sequence element of the SRS sequence is not allocated to different REs. Further, for each

SRS resource

510 or 520, a sequence element of the SRS sequence is mapped to a single subcarrier, e.g., in an order of the subcarrier index, such that the mapped sequence elements are arranged in accordance with the comb type configuration. Thus, the sequence elements are mapped to the subcarriers across the full bandwidth of the two SRS resources.

In an example embodiment, to facilitate the mapping operation, the whole SRS sequence generated based on the virtual SRS resource may be divided into a number of different parts corresponding to the configured SRS resources for the UE 110. Then each part may be mapped to the REs of the associated SRS resource. As shown in Fig. 6, a first part 502 of the SRS sequence composed of sequence elements c (0) through c (23) is mapped to the first SRS resource 510, and a second part 504 of the SRS sequence composed of sequence elements c (12) through c (35) is mapped to the second SRS resource 520. In an example, the two

parts

502, 504 of the SRS sequence may be mapped to the

respective SRS resources

510, 520 in an order of the common resource block (CRB) index of the starting RB of the SRS resource.

As discussed above, if parameters such as comb-size, cyclic shift are configured in the configuration information, the UE 110 may follow the configured comb-size and cyclic shift and ignore the previously configured comb-size and cyclic shift of each of the plurality SRS resources. For example, the plurality of SRS resources may be configured with a same comb-size, but with different numbers of symbols.

Figs. 7A and 7B illustrate examples of SRS sequence mapping to the overlapping REs between associated SRS resources when a comb size is configured according to example embodiments of the present disclosure. Different than the mapping shown in Fig. 6, the first SRS resource 510 and the second SRS resource 520 are configured with a same comb size, e.g., based on the comb size of the first SRS resource 510, but the first SRS resource 510 is configured with a less number of symbols than the second SRS resource 520. In this case, the SRS sequence may be mapped so that the sequence elements in both the first SRS resource 510 and the second SRS resource 520 are arranged in accordance with a comb-2 pattern.

In an example, as shown in Fig. 7A, in the overlapping region in the frequency domain of the two SRS resources, the same sequence elements c (12) , c (13) , …, c (23) may be repeatedly mapped to the frequency-domain overlapping REs of the second SRS resource 520 in a same pattern as mapping of the same sequence elements to the frequency-domain overlapping REs of the first SRS resource 510. In another example, as shown in Fig. 7B, the same sequence elements c (12) , c (13) , …, c (23) may be mapped in a same pattern to the frequency-domain overlapping REs of the two SRS resources, and remaining symbols in the second SRS resource 520 are punctured or remain unused.

Turing back to Fig. 4, when the SRS sequence is generated and mapped to the plurality of SRS resources, at an operation 318, the UE 110 may transmit, and the base station 120a may receive, the SRS sequence on the plurality of SRS resources based on the configuration information.

For example, referring to Fig. 5, the UE 110 may perform frequency hopping to transmit the multiple

SRS sequence parts

450, 460, 470 conveyed on the

respective SRS resources

410, 420, 430 to the base station 120a across the UL BWPs, e.g., using transmission beam information configured for the UE 110. On the side of the base station 120a, it may see a single complete ZC sequence across the UL BWPs when the base station 120a combines received signals of the SRS resources.

At an operation 320, the base station 120 may stitch the multiple SRS sequence parts to recover the SRS sequence. For example, the base station 120a may estimate phase discontinuity/difference between the SRS hops and stitch the multiple SRS sequences for coherent processing, so as to obtain the positioning measurements.

Fig. 8 is a message flow diagram illustrating a process for positioning a UE based on a virtual SRS resource configuration according to an example embodiment of the present disclosure. The process shown in Fig. 8 may be performed by for example the UE 110, the base stations 120, and the location server 130.

In case where a UL positioning based on UL PRS (e.g., SRS) is desired, the location server 130 may, at an operation 610, transmit a request to the UE 110 to initiate a positioning procedure. Additionally or alternatively, the location server 130 may transmit a request to the serving base station 120a to initiate the positioning procedure for the UE 110.

At an operation 612, the base station 120a may transmit a virtual SRS resource configuration information to the UE 110. For example, if the base station 120a knows that the UE 110a is a RedCap UE, the base station 120a may configure the UE 110 with a virtual SRS resource associated with a plurality of physical SRS resources previously allocated to the UE 110. The configuration information may further include at least one of sequence generation and mapping information, validation time, and spatial relation information. The details of the configuration information may be substantially the same as the description made with reference to the Fig. 4, and a redundant description thereof is omitted here.

At an operation 614, the base station 120a may transmit the virtual SRS resource configuration information to the location server 130. Upon receiving the configuration information, at an operation 616, the location server 130 may transmit the configuration information to other measuring base stations, e.g.,

base stations

120b, 120c. In an example, the configuration information may be transmitted on top of other SRS resource configuration. For example, the configuration information may be transmitted separately or together with conventional SRS resource configuration that is configured for other purposes.

Then, at an operation 618a, the UE 110 may perform frequency hopping to transmit the SRS sequences across the UL BWPs. Also, at an operation 618b, the UE 110 may transmit the SRS sequences to the

base stations

120b, 120c. Upon receiving the SRS sequences, all measuring base stations may, at

operations

620a, 620b, perform the stitching operation to process the respective frequency hops to obtain the UL positioning measurements based on the SRS sequences. This frequency hopping and stitching operation has been described above with respect to Fig. 4 and a reductant description is omitted here.

After completing the measurements, at

operations

622a, 622b, the measuring

base stations

120a, 120b, 120c may report their positioning measurements to the location server 130, e.g., via NR Positioning Protocol A (NRPPa) signaling. With the measurement report, the location server 130 may, at an operation 624, determine the position of the UE 110.

Fig. 9 shows a flowchart of an example method 700 for frequency hopping and stitching of uplink PRS sequence e.g. SRS sequence in accordance with an example embodiment of the present disclosure. The method 700 can be implemented at a terminal device e.g. the UE 110 discussed above. It would be understood that step illustrated in dashed-line block represent an optional step and can be omitted in some example embodiments. In some example embodiments, the method 700 may further include one or more steps that are performed at the UE 110 as described above with respect to Figs. 4-8. It would also be understood that details of some steps in the procedure 700 have been discussed above with respect to Figs. 4-8 and the procedure 700 will be described here in a simple manner.

At block 710, the terminal device may receive from a network device in a radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device. For example, the plurality of uplink reference signal resources may comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation. Still for example, the plurality of uplink reference signal resources may be located in different uplink bandwidth parts.

In some example embodiments, the configuration information may further indicate at least one of: sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources; validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource. For example, the positioning reference signal sequence may be an uplink positioning reference signal sequence.

In some example embodiments, at least one of the sequence generation and mapping information, the validation time or the spatial relation information associated with the virtual uplink positioning reference signal resource may override corresponding configuration for the plurality of uplink reference signal resources.

At block 720, the terminal device may generate an uplink positioning reference signal sequence e.g. an SRS sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information. For example, the uplink positioning reference signal sequence may be a complete single Zadoff Chu sequence.

In some example embodiments, the uplink positioning reference signal sequence may have a length determined by a sum of a number of subcarriers in the plurality of uplink reference signal resources minus a number of overlapping subcarriers between the plurality of uplink reference signal resources.

In some example embodiments, wherein in a case where two uplink reference signal resources have overlapping subcarriers, two parts of the uplink positioning reference signal sequence mapped to the two uplink reference signal resources may include an overlapping sequence section mapped to the overlapping subcarriers.

In some example embodiments, wherein in a case where the two uplink reference signal resources having the overlapping subcarriers are configured with a same comb size and a different number of symbols, same sequence elements may be mapped in a same pattern to the frequency-domain overlapping resource elements of the two uplink reference signal resources, and remaining symbols in one of the two uplink reference signal resources configured with a larger number of symbols are punctured or remain unused, or same sequence elements may be repeatedly mapped to the frequency-domain overlapping resource elements of the one of the two uplink reference signal resources configured with the larger number of symbols in a same pattern as mapping of the same sequence elements to the frequency-domain overlapping resource elements of the other of the two uplink reference signal resources configured with a less number of symbols.

At block 730, the terminal device may map the uplink positioning reference signal sequence to the plurality of uplink reference signal resources based on the configuration information. For example, the plurality of uplink reference signal resources may convey respective parts of the uplink positioning reference signal sequence. Still for example, a sequence element in the uplink positioning reference signal sequence may be mapped in a frequency domain to one subcarrier among the plurality of uplink reference signal resources.

At block 740, the terminal device may transmit the uplink positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.

Fig. 10 shows a flowchart of an example method 800 for frequency hopping and stitching of uplink PRS sequence e.g. an SRS sequence in accordance with an example embodiment of the present disclosure. The method 800 can be implemented at a network device, e.g., the serving base station 120a discussed above. It would be understood that step illustrated in dashed-line blocks represent an optional step and can be omitted in some example embodiments. In some example embodiments, the method 800 may further include one or more steps that are performed at the base station 120a as described above with respect to Figs. 4-8. It would also be understood that details of some steps in the procedure 800 have been discussed above with respect to Figs. 4-8 and the procedure 800 will be described here in a simple manner.

At block 810, the network device may transmit to a terminal device in a radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device. For example, the plurality of uplink reference signal resources may comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation. Still for example, the plurality of uplink reference signal resources may be located in different uplink bandwidth parts.

In some example embodiments, the configuration information may further indicate at least one of: sequence generation and mapping information for generating the uplink positioning reference signal sequence and mapping the uplink positioning reference signal sequence to the plurality of uplink reference signal resources; validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.

At block 820, the network device may receive from the terminal device, a uplink positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources. For example, the uplink positioning reference signal sequence is a complete single Zadoff Chu sequence.

In some example embodiments, the uplink positioning reference signal sequence may be received on the plurality of uplink reference signal resources based on the at least one of the sequence generation and mapping information, the validation time or the spatial relation information.

At block 830, the network device may stitch the respective parts of the uplink positioning reference signal sequence to recover the uplink positioning reference signal sequence.

At block 840, the network device may transmit the configuration information to a location server.

Fig. 11 shows a flowchart of an example method 900 for frequency hopping and stitching of uplink PRS sequence e.g. an SRS sequence in accordance with an example embodiment of the present disclosure. The method 900 can be implemented at a location server, e.g. the location server 130 discussed above. In some example embodiments, the method 900 may further include one or more steps that are performed at the location server 130 as described above with respect to Figs. 4-8. It would also be understood that details of some steps in the procedure 900 have been discussed above with respect to Figs. 4-8 and the procedure 900 will be described here in a simple manner.

At block 910, the location server may receive from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device.

At block 920, the location server may transmit the configuration information to at least one second network device in the radio access network configured to position the terminal device.

Fig. 12 illustrates a block diagram of an example communication system 1000 in which embodiments of the present disclosure can be implemented. As shown in Fig. 12, the communication system 1000 may comprise a terminal device 1010 which may be implemented as the UE 110 discussed above, a network device 1020 which may be implemented as any one of the base stations 120 discussed above, and a network function node 1030 which may be implemented as the location server 130 discussed above. In some example embodiments, alternatively, the location server 130 may be implemented as a component or part in the network device 1020. Although Fig. 12 shows one network device 1020, it would be appreciated that the communication system 1000 may comprise a plurality of network devices 1020 to position or assist positioning of the terminal device 1010.

Referring to Fig. 12, the terminal device 1010 may comprise one or more processors 1011, one or more memories 1012 and one or more transceivers 1013 interconnected through one or more buses 1014. The one or more buses 1014 may be address, data, or control buses, and may include any interconnection mechanism such as series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers 1013 may comprise a receiver and a transmitter, which are connected to one or more antennas 1016. The terminal device 1010 may wirelessly communicate with the network device 1020 through the one or more antennas 1016. The one or more memories 1012 may include program instruction 1015. The one or more memories 1012 and the program instruction 1015 may be configured to, when executed by the one or more processors 1011, cause the terminal device 1010 to perform operations and procedures relating to the UE 110 as described above.

The network device 1020 may comprise one or more processors 1021, one or more memories 1022, one or more transceivers 1023 and one or more network interfaces 1027 interconnected through one or more buses 1024. The one or more buses 1024 may be address, data, or control buses, and may include any interconnection mechanism such as a series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers 1023 may comprise a receiver and a transmitter, which are connected to one or more antennas 1026. The network device 1020 may operate as a base station for the terminal device 1010 and wirelessly communicate with terminal device 1010 through the one or more antennas 1026. The one or more network interfaces 1027 may provide wired or wireless communication links through which the network device 1020 may communicate with other network devices, entities, elements or functions. The one or more memories 1022 may include program instruction 1025. The network device 1020 may communicate with the network function node 1030 via backhaul connections 1028. The one or more memories 1022 and the program instruction 1025 may be configured to, when executed by the one or more processors 1021, cause the network device 1020 to perform operations and procedures relating to any one of the base stations 120.

The network function node 1030 may comprise one or more processors 1031, one or more memories 1032, and one or more network interfaces 1037 interconnected through one or more buses 834. The one or more buses 1034 may be address, data, or control buses, and may include any interconnection mechanism such as a series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. The network function node 1030 may operate as a core network function node and wired or wirelessly communicate with the network device 1020 through one or more links. The one or more network interfaces 1037 may provide wired or wireless communication links through which the network function node 1030 may communicate with other network devices, entities, elements or functions. The one or more memories 1032 may include program instruction 1035. The one or more memories 1032 and the program instruction 1035 may be configured to, when executed by the one or more processors 1031, cause the network function node 830 to perform operations and procedures relating to the location server 130 as described above.

The one or

more processors

1011, 1021 and 1031 discussed above may be of any appropriate type that is suitable for the local technical network, and may include one or more of general purpose processors, special purpose processor, microprocessors, a digital signal processor (DSP) , one or more processors in a processor based multi-core processor architecture, as well as dedicated processors such as those developed based on Field Programmable Gate Array (FPGA) and Application Specific Integrated Circuit (ASIC) . The one or

more processors

1011, 1021 and 1031 may be configured to control other elements of the UE/network device/network element and operate in cooperation with them to implement the procedures discussed above.

The one or more memories 1012, 1022 and 1032 may include at least one storage medium in various forms, such as a transitory memory and/or a non-transitory memory. The transitory memory may include, but not limited to, for example, a random access memory (RAM) or a cache. The non-transitory memory may include, but not limited to, for example, a read only memory (ROM) , a hard disk, a flash memory, and the like. 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. ROM) . Further, the one or more memories 1012, 1022 and 1032 may include but not limited to an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

It would be understood that blocks in the drawings may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In some embodiments, one or more blocks may be implemented using software and/or firmware, for example, machine-executable instructions stored in the storage medium. In addition to or instead of machine-executable instructions, parts or all of the blocks in the drawings 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-Chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , etc.

Fig. 13 is a schematic functional block diagram illustrating an apparatus 1100 according to an example embodiment of the present disclosure. The apparatus 1100 may be implemented at a terminal device like the UE 110 to perform operations relating to the UE 110 as discussed above. Since the operations relating to the UE 110 have been discussed in detail with reference to Figs. 4-8, the blocks of the apparatus 1100 will be described briefly here and details thereof may refer to the above description.

Referring to Fig. 13, the apparatus 1100 may include a first means 1110 for receiving from a network device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device, a second means 1120 for generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information, and a third means 1130 for transmitting the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information

In some example embodiments, transmitting the positioning reference signal sequence may comprise: mapping the positioning reference signal sequence to the plurality of uplink reference signal resources based on the configuration information, the plurality of uplink reference signal resources may convey respective parts of the positioning reference signal sequence; and transmitting the respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources.

In some example embodiments, the plurality of uplink reference signal resources may comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation.

In some example embodiments, the configuration information may further indicate at least one of: sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources; validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.

In some example embodiments, the positioning reference signal sequence may have a length determined by a sum of a number of subcarriers in the plurality of uplink reference signal resources minus a number of overlapping subcarriers between the plurality of uplink reference signal resources.

In some example embodiments, in a case where two uplink reference signal resources have overlapping subcarriers, two parts of the positioning reference signal sequence mapped to the two uplink reference signal resources may include an overlapping sequence section mapped to the overlapping subcarriers.

In some example embodiments, a sequence element in the positioning reference signal sequence is mapped in a frequency domain to one subcarrier among the plurality of uplink reference signal resources.

In some example embodiments, the plurality of uplink reference signal resources may be located in different uplink bandwidth parts.

In some example embodiments, the positioning reference signal sequence is a complete single Zadoff Chu sequence.

Fig. 14 is a schematic functional block diagram illustrating an apparatus 1200 according to an example embodiment of the present disclosure. The apparatus 1200 may be implemented at a network node like the base station 120a to perform operations relating to the base station 120a as discussed above. Since the operations relating to the base station 120a have been discussed in detail with reference to Figs. 4-8, the blocks of the apparatus 1200 will be described briefly here and details thereof may refer to the above description.

Referring to Fig. 14, the apparatus 1200 may include a first means 1210 for transmitting to a terminal device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and a second means 1220 for receiving from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.

In some example embodiments, receiving the positioning reference signal sequence may comprise: receiving respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources; and stitching the respective parts of the positioning reference signal sequence to recover the positioning reference signal sequence.

In some example embodiments, the positioning reference signal sequence may be received on the plurality of uplink reference signal resources based on the at least one of the sequence generation and mapping information, the validation time or the spatial relation information.

In some example embodiments, the apparatus 1200 may further include a third means for transmitting the configuration information to a location server.

In some example embodiments, the plurality of sounding reference signal resources may be located in different uplink bandwidth parts.

In some example embodiments, the positioning reference signal sequence may be a complete single Zadoff Chu sequence.

Fig. 15 is a schematic functional block diagram illustrating an apparatus 1300 according to an example embodiment of the present disclosure. The apparatus 1300 may be implemented at a network function like the location server 130 to perform operations relating to the location server 130 as discussed above. Since the operations relating to the location server 130 have been discussed in detail with reference to Figs. 4-8, the blocks of the apparatus 1300 will be described briefly here and details thereof may refer to the above description.

Referring to Fig. 15, the apparatus 1300 may include a first means 1310 for receiving from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and a second means 1320 for transmitting the configuration information to at least one second network device in the radio access network configured to position the terminal device.

Some exemplary embodiments further provide program instruction or instructions which, when executed by one or more processors, may cause a device or apparatus to perform the procedures described above. The program instruction for carrying out procedures of the exemplary embodiments may be written in any combination of one or more programming languages. The program instruction may be provided to one or more processors or controllers of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program instruction, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program instruction 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.

Some exemplary embodiments further provide a computer program product or a computer readable medium having the program instruction or instructions stored therein. The computer readable medium may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but is 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 machine 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.

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 the elements.

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 subject matter has been described in a language that is specific to structural features and/or method actions, it is to be understood the subject matter defined in the appended claims is not limited to the specific features or actions described above. On the contrary, the above-described specific features and actions are disclosed as an example of implementing the claims.

Claims

A terminal device in a radio access network comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the terminal device at least to:

receive from a network device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device;

generate a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and

transmit the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.
The terminal device of claim 1 wherein transmitting the positioning reference signal sequence comprises:

mapping the positioning reference signal sequence to the plurality of uplink reference signal resources based on the configuration information, the plurality of uplink reference signal resources conveying respective parts of the positioning reference signal sequence; and

transmitting the respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources.
The terminal device of claim 1 wherein the plurality of uplink reference signal resources comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation.
The terminal device of claim 1 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
The terminal device of claim 4 wherein the at least one of the sequence generation and mapping information, the validation time or the spatial relation information associated with the virtual uplink positioning reference signal resource overrides corresponding configuration for the plurality of uplink reference signal resources.
The terminal device of claim 1 wherein the positioning reference signal sequence has a length determined by a sum of a number of subcarriers in the plurality of uplink reference signal resources minus a number of overlapping subcarriers between the plurality of uplink reference signal resources.
The terminal device of claim 2 wherein in a case where two uplink reference signal resources have overlapping subcarriers, two parts of the positioning reference signal sequence mapped to the two uplink reference signal resources include an overlapping sequence section mapped to the overlapping subcarriers.
The terminal device of claim 7 wherein in a case where the two uplink reference signal resources having the overlapping subcarriers are configured with a same comb size and a different number of symbols,

same sequence elements are mapped in a same pattern to the frequency-domain overlapping resource elements of the two uplink reference signal resources, and remaining symbols in one of the two uplink reference signal resources configured with a larger number of symbols are punctured or remain unused, or

same sequence elements are repeatedly mapped to the frequency-domain overlapping resource elements of the one of the two uplink reference signal resources configured with the larger number of symbols in a same pattern as mapping of the same sequence elements to the frequency-domain overlapping resource elements of the other of the two uplink reference signal resources configured with a less number of symbols.
The terminal device of claim 7 wherein a sequence element in the positioning reference signal sequence is mapped in a frequency domain to one subcarrier among the plurality of uplink reference signal resources.
The terminal device of claim 1 wherein the plurality of uplink reference signal resources are located in different uplink bandwidth parts.
The terminal device of claim 1 wherein the positioning reference signal sequence is a complete single Zadoff Chu sequence.
A network device in a radio access network comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the network device at least to:

transmit to a terminal device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

receive from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.
The network device of claim 12 wherein receiving the positioning reference signal sequence comprises:

receiving respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources; and

stitching the respective parts of the positioning reference signal sequence to recover the positioning reference signal sequence.
The network device of claim 12 wherein the plurality of uplink reference signal resources comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation.
The network device of claim 12 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
The network device of claim 15 wherein the positioning reference signal sequence is received on the plurality of uplink reference signal resources based on the at least one of the sequence generation and mapping information, the validation time or the spatial relation information.
The network device of claim 12 wherein the at least one memory further stores instructions that, when executed by the at least one processor, cause the network device at least to:

transmit the configuration information to a location server.
The network device of claim 12 wherein the plurality of sounding reference signal resources are located in different uplink bandwidth parts.
The network device of claim 12 wherein the positioning reference signal sequence is a complete single Zadoff Chu sequence.
A location server comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the location server at least to:

receive from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

transmit the configuration information to at least one second network device in the radio access network configured to position the terminal device.
The location server of claim 20 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
A method implemented at a terminal device in a radio access network, comprising:

receiving from a network device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device;

generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and

transmitting the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.
The method of claim 22 wherein transmitting the positioning reference signal sequence comprises:

mapping the positioning reference signal sequence to the plurality of uplink reference signal resources based on the configuration information, the plurality of uplink reference signal resources conveying respective parts of the positioning reference signal sequence; and

transmitting the respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources.
The method of claim 22 wherein the plurality of uplink reference signal resources comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation.
The method of claim 22 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
The method of claim 25 wherein the at least one of the sequence generation and mapping information, the validation time or the spatial relation information associated with the virtual uplink positioning reference signal resource overrides corresponding configuration for the plurality of uplink reference signal resources.
The method of claim 22 wherein the positioning reference signal sequence has a length determined by a sum of a number of subcarriers in the plurality of uplink reference signal resources minus a number of overlapping subcarriers between the plurality of uplink reference signal resources.
The method of claim 23 wherein in a case where two uplink reference signal resources have overlapping subcarriers, two parts of the positioning reference signal sequence mapped to the two uplink reference signal resources include an overlapping sequence section mapped to the overlapping subcarriers.
The method of claim 28 wherein in a case where the two uplink reference signal resources having the overlapping subcarriers are configured with a same comb size and a different number of symbols,

same sequence elements are mapped in a same pattern to the frequency-domain overlapping resource elements of the two uplink reference signal resources, and remaining symbols in one of the two uplink reference signal resources configured with a larger number of symbols are punctured or remain unused, or

same sequence elements are repeatedly mapped to the frequency-domain overlapping resource elements of the one of the two uplink reference signal resources configured with the larger number of symbols in a same pattern as mapping of the same sequence elements to the frequency-domain overlapping resource elements of the other of the two uplink reference signal resources configured with a less number of symbols.
The method of claim 28 wherein a sequence element in the positioning reference signal sequence is mapped in a frequency domain to one subcarrier among the plurality of uplink reference signal resources.
The method of claim 22 wherein the plurality of uplink reference signal resources are located in different uplink bandwidth parts.
The method of claim 22 wherein the positioning reference signal sequence is a complete single Zadoff Chu sequence.
A method implemented at a network device in a radio access network, comprising:

transmitting to a terminal device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

receiving from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.
The method of claim 33 wherein receiving the positioning reference signal sequence comprises:

receiving respective parts of the positioning reference signal sequence on the plurality of uplink reference signal resources; and

stitching the respective parts of the positioning reference signal sequence to recover the positioning reference signal sequence.
The method of claim 33 wherein the plurality of uplink reference signal resources comprise sounding reference signal resources configured for at least one of uplink channel estimation, positioning, or a multiple input multiple output related operation.
The method of claim 33 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating the positioning reference signal sequence and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
The method of claim 36 wherein the positioning reference signal sequence is received on the plurality of uplink reference signal resources based on the at least one of the sequence generation and mapping information, the validation time or the spatial relation information.
The method of claim 33 further comprising:

transmitting the configuration information to a location server.
The method of claim 33 wherein the plurality of sounding reference signal resources are located in different uplink bandwidth parts.
The method of claim 33 wherein the positioning reference signal sequence is a complete single Zadoff Chu sequence.
A method implemented at a location server, comprising:

receiving from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

transmitting the configuration information to at least one second network device in the radio access network configured to position the terminal device.
The method of claim 41 wherein the configuration information further indicates at least one of:

sequence generation and mapping information for generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource and mapping the positioning reference signal sequence to the plurality of uplink reference signal resources;

validation time of association between the virtual uplink positioning reference signal resource and the plurality of uplink reference signal resources; or

spatial relation information indicative of one or more beams for the plurality of uplink reference signal resources associated with the virtual uplink positioning reference signal resource.
An apparatus comprising:

means for receiving from a network device in a radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device;

means for generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and

means for transmitting the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information.
The apparatus of claim 43, further comprising means for performing the method of any of claims 23 to 32.
An apparatus comprising:

means for transmitting to a terminal device in a radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

means for receiving from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.
The apparatus of claim 45, further comprising means for performing the method of any of claims 34 to 40.
An apparatus comprising:

means for receiving from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

means for transmitting the configuration information to at least one second network device in the radio access network configured to position the terminal device.
A computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to at least perform:

receiving from a network device in the radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device;

generating a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource based on the configuration information; and

transmitting the positioning reference signal sequence on the plurality of uplink reference signal resources based on the configuration information..
The computer readable medium of claim 48, further comprising instructions that, when executed by the apparatus, cause the apparatus to perform the method of any of claims 23 to 32.
A computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to at least perform:

transmitting to a terminal device in a radio access network, configuration information indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

receiving from the terminal device, a positioning reference signal sequence corresponding to the virtual uplink positioning reference signal resource on the plurality of uplink reference signal resources.
The computer readable medium of claim 50, further comprising instructions that, when executed by the apparatus, cause the apparatus to perform the method of any of claims 34 to 40.
A computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to at least perform:

receiving from a first network device in a radio access network, configuration information for a terminal device in the radio access network indicative of a virtual uplink positioning reference signal resource associated with a plurality of uplink reference signal resources allocated to the terminal device; and

transmitting the configuration information to at least one second network device in the radio access network configured to position the terminal device.