Method for SRS with reduced positioning resource overhead in multi-RTT

Abstract

Methods, apparatus, and computer programs for SRS with reduced positioning resource overhead in multi-RTT are provided. A method for a UE includes: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on receive beams used for receiving downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction in at least one beam resource associated with the sounding reference signal used for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams. Methods for a radio node and for an LMF are also provided.

Description

Technical Field

[0001] The exemplary and non-limiting embodiments relate generally to communications, and more particularly to methods for positioning resource overhead-reduced SRS in multi-RTT. Background Art

[0002] This application claims priority to U.S. Application No. 16 / 876,686, filed May 18, 2020. It is known to provide systems for position estimation, such as the Global Positioning System (GPS). Summary of the Invention

[0003] The following summary is intended to be exemplary only. It is not intended to limit the scope of the claims.

[0004] An example method includes: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam used for receiving downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal used for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0005] Another example method includes: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for the positioning configuration, wherein the updated sounding reference signal for the positioning configuration is based on a reduction of at least one beam resource.

[0006] Another example method includes: providing a multi-cell round trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node.

[0007] An example apparatus includes at least one processor; and at least one non-volatile memory including computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam for receiving downlink positioning reference signals from one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0008] Another example apparatus includes at least one processor; and at least one non-volatile memory including computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource.

[0009] Another example apparatus includes at least one processor; and at least one non-volatile memory including computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: providing a multi-cell round trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node.

[0010] An exemplary non-transitory program storage device readable by a machine is provided, the non-transitory program storage device tangibly embodying an instruction program executable by the machine for performing operations, the operations comprising: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam for receiving downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0011] Another exemplary non-transitory program storage device readable by a machine is provided, the non-transitory program storage device tangibly embodying a program of instructions executable by the machine for performing operations, the operations comprising: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource.

[0012] Another exemplary non-transitory program storage device readable by a machine is provided, the non-transitory program storage device tangibly embodying a program of instructions executable by the machine for performing operations, the operations comprising: providing a multi-cell round trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The foregoing aspects and other features are explained in the following description in conjunction with the accompanying drawings, in which:

[0014] Figure 1 is a block diagram of one possible and non-limiting system in which example embodiments may be practiced.

[0015] Figure 2 Describes an overview of multi-RTT technology.

[0016] Figure 3 The SRS-P configuration problem is depicted, where the same beam is selected for both transmissions.

[0017] Figure 4 is a diagram illustrating an example signaling flow based on the method described herein.

[0018] Figure 5 An example of beam overlap is depicted.

[0019] Figure 6 is a diagram depicting an example of UL and DL link budget evaluation.

[0020] Figure 7 is a diagram showing an example estimation of the number or ID of SRSs.

[0021] Figure 8 is a diagram showing an example of UE panel selection for UL SRS transmission.

[0022] Figure 9is an example apparatus configured to implement SRS for positioning resource overhead reduction in multi-RTT based on the examples described herein.

[0023] Figure 10 An example method for SRS with reduced positioning resource overhead in multi-RTT based on the examples described herein is shown.

[0024] Figure 11 Another example method for SRS with reduced positioning resource overhead in multi-RTT based on the examples described herein is shown.

[0025] Figure 12 Another example method for SRS with reduced positioning resource overhead in multi-RTT based on the examples described herein is shown. DETAILED DESCRIPTION

[0026] When more than one drawing reference numeral is used in this specification together with “ / ”, and generally, as used in this specification, “ / ” can be interpreted as “or”, “and” or “both”.

[0027] The following acronyms and abbreviations that may be found in the specification and / or drawings are defined as follows:

[0028] 3GPP: Third Generation Partnership Project

[0029] 4G: Fourth Generation

[0030] 5G: Fifth Generation

[0031] 5GC: 5G core network

[0032] AMF: Access and Mobility Management Function

[0033] Ant: Antenna

[0034] AoA: Angle of Arrival

[0035] BF: Beamforming

[0036] CR: Change Request

[0037] CU: Central Unit or Centralized Unit

[0038] DL: Downlink

[0039] DL-AoD: Downlink Angle of Departure

[0040] DL PRS: Downlink Positioning Reference Signal

[0041] DL-TDOA: Downlink Time Difference of Arrival

[0042] DU: Distributed Unit

[0043] DSP: Digital Signal Processor

[0044] EKF: Extended Kalman Filter

[0045] eNB: Evolved Node B (e.g., LTE base station)

[0046] EN-DC: E-UTRA-NR Dual Connectivity

[0047] en-gNB: A node that provides NR user plane and control plane protocol termination towards the UE and acts as a secondary node in EN-DC

[0048] E-UTRA: Evolved Universal Terrestrial Radio Access, also known as LTE radio access technology

[0049] F1: Control interface between CU and DU

[0050] FR1 and FR2: Frequency Range 1 and Frequency Range 2

[0051] gNB: A base station for 5G / NR, i.e., a node that provides NR user plane and control plane protocol termination towards the UE and is connected to the 5GC via the NG interface

[0052] GPS: Global Positioning System

[0053] I / F: Interface

[0054] Id or ID: Identifier

[0055] incl.: including

[0056] I / O: Input / Output

[0057] IoT: Internet of Things

[0058] (I)IoT: Industrial Internet of Things

[0059] LCS: Location Services

[0060] LMF: Location Management Function

[0061] LPP: LTE Positioning Protocol

[0062] LTE: Long Term Evolution (4G)

[0063] MAC: Media Access Control

[0064] MME: Mobility Management Entity

[0065] Multi-RTT: Multi-cell round-trip time

[0066] ng or NG: New Generation

[0067] ng-eNB: Next-generation eNB

[0068] NG-RAN: Next Generation Radio Access Network

[0069] NN: Neural Network

[0070] NR: New Radio (5G)

[0071] NRPPa: New Radiolocation Protocol A

[0072] N / W or NW: Network

[0073] PDCP: Packet Data Convergence Protocol

[0074] PHY: Physical layer

[0075] PRS: Positioning Reference Signal

[0076] PRS-RSRP: PRS reference signal received power

[0077] R1-: 3GPP RAN 1

[0078] RAN: Radio Access Network

[0079] RAN1: RAN WG1 or Radio Layer 1

[0080] RAN2: RAN WG2 or Radio Layer 2

[0081] RAN3: RAN WG3

[0082] RAT: Radio Access Technology

[0083] Rel-: version

[0084] RLC: Radio Link Control

[0085] RP-: 3GPP RAN

[0086] RRC: Radio Resource Control

[0087] RRH: Remote Radio Head

[0088] RS: Reference signal

[0089] RSRP: Reference Signal Received Power

[0090] RTT: Round Trip Time

[0091] RU: Radio Unit

[0092] Rx or RX: Receiver or Receiver interchangeably

[0093] SDAP: Service Data Adaptation Protocol

[0094] SGW: Serving Gateway

[0095] SID: Shared Information / Data

[0096] SINR: Signal to Interference and Noise Ratio

[0097] SMF: Session Management Function

[0098] SRS: Sounding Reference Signal

[0099] SRS-P: SRS for positioning

[0100] TOA: Time of Arrival

[0101] TPC: Transmit Power Control

[0102] TS: Technical Specification

[0103] Tx or TX: Transmitter or Transmitter interchangeably

[0104] UE: User Equipment (e.g., wireless device, typically a mobile device)

[0105] UL: Uplink

[0106] UL-AoA: Uplink Angle of Arrival

[0107] UL-TDOA: Uplink Time Difference of Arrival

[0108] UPF: User Plane Function

[0109] WG: Working Group

[0110] WID: Work Item Description

[0111] Steering Figure 1 , which shows a block diagram of one possible and non-limiting example in which the examples may be practiced. A user equipment (UE) 110, a radio access network (RAN) node 170 and (multiple) network elements 190 are shown. In Figure 1In the example of FIG1 , user equipment (UE) 110 wirelessly communicates with wireless network 100. A UE is a wireless device that can access wireless network 100. UE 110 includes one or more processors 120, one or more memories 125, and one or more transceivers 130, interconnected by one or more buses 127. Each of the one or more transceivers 130 includes a receiver (Rx) 132 and a transmitter (Tx) 133. The one or more buses 127 can be address, data, or control buses and can include any interconnection mechanism, such as a series of wires on a motherboard or integrated circuit, optical fiber, or other optical communication device. The one or more transceivers 130 are connected to one or more antennas 128. The one or more memories 125 include computer program code 123. UE 110 includes module 140, which includes one or both of portion 140-1 and / or portion 140-2, which can be implemented in a variety of ways. Module 140 can be implemented in hardware as module 140-1, such as as part of one or more processors 120. Module 140-1 may also be implemented as an integrated circuit or through other hardware implementations such as a programmable gate array. In another example, module 140 may be implemented as module 140-2, which is implemented as computer program code 123 and executed by one or more processors 120. For example, one or more memories 125 and computer program code 123 may be configured to, together with one or more processors 120, cause user equipment 110 to perform one or more of the operations described herein. UE 110 communicates with RAN node 170 via wireless link 111. Modules 140-1 and 140-2 may be configured to implement the functionality of the UE as described herein.

[0112] In this example, RAN node 170 is a base station that provides wireless devices (such as UE 110) with access to wireless network 100. RAN node 170 may be, for example, a base station for 5G, also known as New Radio (NR). In 5G, RAN node 170 may be an NG-RAN node, which is defined as a gNB or ng-eNB. A gNB is a node that provides NR user plane and control plane protocol termination towards the UE and is connected to the 5GC (e.g., network element(s) 190) via an NG interface. An ng-eNB is a node that provides E-UTRA user plane and control plane protocol termination towards the UE and is connected to the 5GC via an NG interface. An NG-RAN node may include multiple gNBs, which may also include a central unit (CU) (gNB-CU) 196 and distributed unit(s) (gNB-DU), with DU 195 being shown. Note that DU 195 may include, be coupled to, and control a radio unit (RU). The gNB-CU 196 is a logical node that hosts the radio resource control (RRC), SDAP, and PDCP protocols for a gNB, or the RRC and PDCP protocols for an en-gNB, controlling the operation of one or more gNB-DUs. The gNB-CU 196 terminates the F1 interface with the gNB-DU 195. The F1 interface is shown as reference numeral 198, although reference numeral 198 also illustrates links between remote and centralized elements of the RAN node 170, such as the link between the gNB-CU 196 and the gNB-DU 195. The gNB-DU 195 is a logical node that hosts the RLC, MAC, and PHY layers of a gNB or en-gNB, and its operation is controlled in part by the gNB-CU 196. One gNB-CU 196 supports one or more cells. A cell is supported by only one gNB-DU 195. The gNB-DU 195 terminates the F1 interface 198 with the gNB-CU 196. Note that the DU 195 is considered to include the transceiver 160, e.g., as part of the RU, but some examples in this regard may have the transceiver 160 as part of a separate RU, e.g., under the control of and connected to the DU 195. The RAN node 170 may also be an eNB (evolved NodeB) base station for LTE (Long Term Evolution), or any other suitable base station or node.

[0113] The RAN node 170 includes one or more processors 152, one or more memories 155, one or more network interfaces (N / WI / F) 161, and one or more transceivers 160, interconnected via one or more buses 157. Each of the one or more transceivers 160 includes a receiver Rx 162 and a transmitter Tx 163. The one or more transceivers 160 are connected to one or more antennas 158. The one or more memories 155 include computer program code 153. The CU 196 may include processor(s) 152, memory(s) 155, and network interface 161. Note that the DU 195 may also include its own memory / memory(s) and processor(s), and / or other hardware, but these are not shown.

[0114] RAN node 170 includes module 150, which includes one or both of portion 150-1 and / or portion 150-2, which can be implemented in a variety of ways. Module 150 can be implemented in hardware as module 150-1, such as as part of one or more processors 152. Module 150-1 can also be implemented as an integrated circuit or through other hardware implementations, such as a programmable gate array. In another example, module 150 can be implemented as module 150-2, which is implemented as computer program code 153 and executed by one or more processors 152. For example, one or more memories 155 and computer program code 153 are configured to, together with one or more processors 152, cause RAN node 170 to perform one or more of the operations described herein. Note that the functionality of module 150 can be distributed, such as between DU 195 and CU 196, or implemented solely in DU 195. Modules 150-1 and 150-2 can be configured to implement the functionality of the base station described herein. Such functions of the base station may include a location management function (LMF) implemented based on the functions of the LMF described herein. Such an LMF may also be implemented within the RAN node 170 as a location management component (LMC).

[0115] One or more network interfaces 161 communicate over a network, such as via link 176 and link 131. Two or more gNBs 170 may communicate using, for example, link 176. Link 176 may be wired or wireless or both, and may implement, for example, an Xn interface for 5G, an X2 interface for LTE, or other suitable interfaces for other standards.

[0116] The one or more buses 157 may be address, data, or control buses and may include any interconnection mechanism, such as a series of wires on a motherboard or integrated circuit, optical fiber or other optical communication equipment, a wireless channel, etc. For example, the one or more transceivers 160 may be implemented as a remote radio head (RRH) 195 for LTE, or a distributed unit (DU) 195 for a gNB implementation for 5G, where other elements of the RAN node 170 may be physically located at a different location than the RRH / DU 195, and the one or more buses 157 may be implemented in part, for example, as fiber optic cables or other suitable network connections for connecting other elements of the RAN node 170 (e.g., central unit (CU), gNB-CU) to the RRH / DU 195. Reference numeral 198 also indicates these suitable network link(s).

[0117] Note that the description herein indicates that a "cell" performs a function, but it should be clear that the device that forms the cell can perform that function. A cell constitutes part of a base station. That is, each base station can have multiple cells. For example, for a single carrier frequency and associated bandwidth, there can be three cells, each covering one-third of a 360-degree area, so the coverage area of a single base station covers an approximately elliptical or circular area. In addition, each cell can correspond to a single carrier, and a base station can use multiple carriers. So if there are three 120-degree cells per carrier and there are two carriers, the base station has a total of six cells.

[0118] The wireless network 100 may include one or more network elements 190, which may include core network functions and provide connectivity to another network (e.g., the Internet) such as a telephone network and / or a data communication network via one or more links 181. Such core network functions for 5G may include location management functions (LMFs) and / or access and mobility management functions (AMFs) and / or user plane functions (UPFs) and / or session management functions (SMFs). Such core network functions for LTE may include MME (Mobility Management Entity) / SGW (Serving Gateway) functions. These are merely example functions that may be supported by the network element(s) 190, and it is noted that both 5G and LTE functions may be supported. The RAN node 170 is coupled to the network element 190 via a link 131. The link 131 may be implemented, for example, as an NG interface for 5G, or an S1 interface for LTE, or other suitable interfaces for other standards. Network element 190 includes one or more processors 175, one or more memories 171, and one or more network interfaces (N / WI / F) 180 interconnected by one or more buses 185. One or more memories 171 include computer program code 173. One or more memories 171 and computer program code 173 are configured to, together with one or more processors 175, cause network element 190 to perform one or more operations, such as the functionality of the LMF described herein. In some examples, a single LMF can serve a large area covered by hundreds of base stations.

[0119] Wireless network 100 can implement network virtualization, which is the process of combining hardware and software network resources and network functions into a single, software-based managed entity (virtual network). Network virtualization involves platform virtualization, which is often used in conjunction with resource virtualization. Network virtualization can be categorized as either external network virtualization or internal network virtualization. External network virtualization combines multiple networks or network components into virtual units, while internal network virtualization provides network-like functionality to software containers on a single system. Note that the virtualized entities created by network virtualization are still implemented to some extent using hardware, such as processors 152 or 175 and memories 155 and 171, and this virtualized entity also produces technical effects.

[0120] Computer-readable memories 125, 155, and 171 may be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. Computer-readable memories 125, 155, and 171 may be components for performing storage functions. Processors 120, 152, and 175 may be of any type suitable for the local technical environment and, as non-limiting examples, may include one or more of a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Processors 120, 152, and 175 may be components for performing functions, such as controlling UE 110, RAN node 170, network element(s) 190, and other functions described herein.

[0121] In general, various embodiments of the user device 110 may include, but are not limited to, a cellular telephone with wireless communication capabilities (such as a smart phone, a tablet computer, a personal digital assistant (PDA)), a portable computer with wireless communication capabilities, an image capture device with wireless communication capabilities (such as a digital camera), a gaming device with wireless communication capabilities, a music storage and playback device with wireless communication capabilities, an Internet device allowing wireless Internet access and browsing, a tablet computer with wireless communication capabilities, and a portable unit or terminal incorporating a combination of such functionalities.

[0122] A Rel-16 work item [RP-190752, “New WID: NR Positioning Support”] was undertaken in 3GPP for local positioning support in New Radio (NR). As a result of this work, the following positioning solutions were specified for NR Rel-16 (note that RAN1 has completed its work, while RAN2 / 3 are finalizing the signaling details):

[0123] -Downlink Time Difference of Arrival (DL-TDOA)

[0124] -Uplink Time Difference of Arrival (UL-TDOA)

[0125] - Downlink Angle of Departure (DL-AoD)

[0126] -Uplink Angle of Arrival (UL-AoA)

[0127] -Multi-cell round-trip time (Multi-RTT)

[0128] The work is to specify solutions to enable RAT-dependent (for both FR1 and FR2) and RAT-independent NR positioning techniques. FR1 is below 6 GHz, while FR2 is in the range of 24.25 GHz to 52.6 GHz. In the DL, a new Positioning Reference Signal (PRS) is introduced, while in the UL, a new SRS (SRS-P) for positioning is introduced [R1-1913661, Positioning CR to TS 38.211].

[0129] In Release 17, NR positioning will be further studied with the following main objectives [RP-193237, New SID for Positioning Enhancement]:

[0130] "Study the enhancements and solutions needed to support the high accuracy (horizontal and vertical), low latency, network efficiency (scalability, RS overhead, etc.), and device efficiency (power consumption, complexity, etc.) requirements of commercial use cases, including general commercial use cases and (I)IoT use cases in particular."

[0131] Multi-RTT is one of the methods specified in Rel-16 and relies on both UL and DL measurements / signals. Figure 2 An example overview of the technique is shown. At a high level, the method operates by multiple gNBs 170-1 / 170-2 / 170-3 transmitting DL PRS 104 / 108 / 112 to UE 110-1, and UE 110-1 then transmitting SRS-P 105 / 109 / 113 to gNBs 170-1 / 170-2 / 170-3. UE 110-1 measures 115 the UE Rx-Tx time difference for each cell, while each gNB 170-1 / 170-2 / 170-3 measures (e.g., 107) the gNB Rx-Tx time difference for UE 110-1. The measurement results are reported 116 / 118 to the location management function (LMF) 190-1, which can then estimate the RTT from UE 110-1 to each gNB 170-1 / 170-2 / 170-3 and, therefore, the location of UE 110-1. Figure 2 In the example shown, UE 110-1 reports measurements via LTE Positioning Protocol (LPP) 116, and gNBs 170-1 / 170-2 / 170-3 report measurements via New Radio Positioning Protocol A (NRPPa) 118.

[0132] Multi-cell RTT is a method used for Rel-16 NR positioning, which has higher accuracy due to the absence of synchronization errors and the wide bandwidth available (better timing measurement accuracy). At FR2, the UE needs to beamform the UL transmission and potentially perform TPC to neighboring cells to close the UL link budget and / or overcome high path loss.

[0133] To address this issue, SRS-P can be enhanced so that the spatial relationship information (e.g., as a parameter spatialRelationInfo) uses the neighboring cell RS as a reference. Spatial relationship configures the UE to select the RX beam used to receive the reference RS as the TX beam for SRS-P. This enables the UE to perform UL beamforming towards neighboring cells for positioning purposes. Therefore, based on receiving multiple DL PRS beams from multiple gNBs, the UE can be configured to use the best beam for transmission for multiple cells. However, spatialRelationInfo is selected by the LMF, and the LMF requires a previous report of the DL PRS-RSRP from the UE in order to know which resources to configure as spatial relationship, but the LMF does not know which beams the UE can use.

[0134] Furthermore, a relatively large number of cells (e.g., 12-15 cells) may be involved in a user's multi-RTT. A spatialRelationInfo may be configured for each SRS-P resource, causing the UE to then transmit one SRS-P resource per cell (which may be a significant overhead). In fact, the UE may even use the same (or similar) RX beam to receive the best DLPRS from multiple cells, thus using the same TX beam on multiple SRS resources, which represents wasted overhead and unnecessary power consumption at the UE. Figure 3 An example is shown in which UE 110 - 1 is configured with four spatial relationships for four SRS resources ( SRS 1 , SRS 2 , SRS 3 , and SRS 4 ) but uses the same beam for transmission for two of these resources ( SRS 1 and 4 ). Figure 3 Also shown are base stations 170-1, 170-2, 170-3, and 170-4.

[0135] The examples described herein address this overhead issue by minimizing the number of SRS-P resources while maintaining transmission to each cell involved in the multi-RTT.

[0136] Most existing techniques are concerned with selecting the best beam for the serving cell only (e.g., for data purposes) and do not consider the need to transmit to neighboring cells in a beamforming manner. As mentioned earlier, enhancements to SRS-P to allow configuration of spatial relationships for neighboring cells were introduced in Rel-16. The latest version of TS 38.214 "Physical Layer Procedures for Data" (V16.0.0, 3GPP, Section 6.2.1.4) provides:

[0137] “When SRS is configured by the higher-layer parameter [SRS-for-Positioning], and if the higher-layer parameter spatialRelationInfo contains an ID that references 'DL-PRS-ResourceId', the UE shall transmit the target SRS resource using the same spatial domain transmit filter used for reception of the reference DL PRS.”

[0138] Configuring spatialRelationInfo for each cell for multiple RTTs is one approach, but this does not solve the problem if multiple resources end up with the same transmission beam on the UE side, as previously mentioned. The approach provided and described herein solves the problem of minimizing the number of SRS-P resources that still reach each cell.

[0139] Thus, the examples described herein provide a method for reducing SRS-P resource overhead for multi-cell RTT. Figure 4 An overall signaling flow of an example method with novel steps explained herein is shown. Several aspects and additional detailed embodiments are described.

[0140] Figure 4 UE 110-1, serving gNB 170-3, neighboring gNB 170-1, and LMF 190-1 are depicted. It should be understood that although Figure 4 One neighboring gNB 170-1 is shown in FIG, but Figure 4 The signaling shown may include transmissions to / from neighboring gNBs other than neighboring gNB 170-1. Figure 4 The steps in the example are numbered 1-10, but in some examples the numbered steps may not be Figure 4 The numbers appear in the order shown.

[0141] exist Figure 4 In the example shown, LMF 190-1 provides a multi-RTT positioning request for K cells to serving gNB 170-3 in step 1, which is sent from LMF 190-1 or serving gNB 170-3 to UE 110-1. UE 110-1, which performs multi-cell RTT to K cells, is configured with K SRS resources (in step 2) containing the configured spatial relationship information (assuming DL / UL beam correspondence). Figure 4 In step 2, serving gNB 170-3 configures K SRS resources to UE 110-1.

[0142] In step 3, serving gNB 170-3 provides overlapping assistance information to UE 110-1. Thus, in step 3, the network can signal auxiliary data to UE 110-1 to assist in overlapping selection (e.g., minimum link budget). Further details of step 3 are described herein.

[0143] In step 4, serving gNB 170-3 provides an SRS configuration to LMF 190-1. In step 5, LMF 190-1 provides the SRS configuration to adjacent gNB 170-1 (there can be one or more adjacent gNBs). In step 6, serving gNB 170-3 and each of the adjacent gNBs 170-1 transmit DL PRS to UE 110-1.

[0144] In step 7, UE 110-1 measures the DL PRS from K cells and determines an appropriate TX beam based on the RX beam used for DL PRS reception. UE 110-1 can identify the same TX beam for multiple cells, which represents an overlap among M beams (new UE procedure, 7).

[0145] UE 110-1 can also identify beams that overlap with each other in the spatial domain (e.g., in the case of different beam widths).

[0146] UE 110-1 can also scan different UE antenna panels to identify whether a shared TX beam can be used for multiple target cells. This can be done using UE DL AoA calculations from visible gNBs. Based on the AoA, a common UE antenna panel can be used to further reduce TX resources (new UE procedure, 7).

[0147] UE 110-1 notifies the network of the overlap among M < K TX beams (new step / signaling, 8). UE 110-1 can indicate for which additional cells each of the K - M resources is. This signaling can be a new RRC message or a new LPP message. As Figure 4 shown, UE 110-1 provides this updated SRS configuration to serving gNB 170-3 and LMF 190-1 in step 8.

[0148] LMF 190-1 signals the updated SRS configuration to gNBs (such as adjacent gNB 170-1) to ensure SRS reception and correct RX beamforming at the gNBs (new signaling, 9).

[0149] UE 110-1 transmits K - M SRSs for positioning (new step, 10). As Figure 4As shown, in step 10, UE 110-1 transmits KM SRS resources to serving gNB 170-3 and neighboring gNB 170-1. As long as the link constraints set in the assistance data are met, UE 110-1 can transmit a different beamwidth in the UL than the beamwidth used for reception in the DL, which is currently enforced through the use of spatial relations (new step).

[0150] Over time, the LMF 190-1 may track the number of SRS resources required (based on location, mobility, trajectory) to configure the correct number of SRS resources (new step).

[0151] Signaling auxiliary information for overlap selection to the UE (such as in Figure 4 Step 3) can include parameters for link budget calculation, such as the beamforming (BF) gain for the DL PRS resources. The UE can then estimate the link budget to each gNB, given the UE’s receive power and the DL PRS Tx power as part of the DL PRS configuration.

[0152] If the link budget is sufficient, the UE can use wider beams for transmissions to multiple gNBs using a single resource. LMF can also provide the UE with a minimum requested receive power as a threshold for determining whether the link budget is sufficient. The UE can also determine this threshold based on local knowledge or the assumption that the UL receive power needs to be within a defined or specified threshold for the DL receive power. This allows the UE to further reduce SRS transmission overhead by selecting beams that are not only equivalent but also overlap in the spatial domain.

[0153] Figure 5 1 shows an example of how the overlap may look, depicting UE 110-1, gNB 1, gNB 2, SRS 1, and SRS 2. Figure 5 As shown, SRS 1 and SRS 2 overlap. To illustrate the overlap, SRS 2 is depicted as being "above" or "in front of SRS 1" for illustrative purposes. Figure 5 In

[15] , SRS 2 for gNB 2 may not be sent as long as the link budget for the farther gNB is still sufficient using the beam used for SRS 1.

[0154] like Figure 4 As discussed in the discussion of

[15] , the UE can determine that a different UL beam or beamwidth should be used than that used for DL RS reception (in order to exploit overlap). When spatial relations are configured, current standards require the UE to use the same beam in both DL and UL. However, the network can still control how the UE is allowed to make this change through the use of assistance data.

[0155] In some examples, gNB assistance information can be used to widen the UE UL beam based on link budget evaluation. Figure 6 For the link budget shown, the procedure for widening the UL beam for SRS 1 transmission to both gNB 1 and 2 includes the following.

[0156] Serving gNB 170-3 -> UE 110-1: gNB 170-3 requests the use of two SRS resources for multi-RTT measurement and provides assistance information, including the gNB DL power 1002, DL_gNB_Power, the gNB UL / DL incremental antenna gain 1010, gNB_Ant_Delt_Gain, and the UL RSRP minimum target 1004, UL_RSRP_Target.

[0157] gNB 1&2->UE 110-1: gNB 1&2 transmits DL PRS toward UE 110-1.

[0158] UE: UE 110-1 uses the gNB 1 / 2-specific UE DL beam configuration to measure DL PRS 1 and 2. Based on the used UE DL beam configuration (gain and steering angle), the UE evaluates the feasibility of transmitting SRS to both gNBs 1 and 2 using only one UL beam configuration (gain and steering angle). This can be achieved by widening the UL beamwidth, which again results in lower antenna gain towards the gNB.

[0159] Therefore, UE 110-1 evaluates the UL link budget of each gNB to confirm the tolerance to lower antenna gain using the assistance information provided by the gNB and the UE's locally known parameters:

[0160] DL_Path_Loss=DL_gNB_Power+DL_gNB_Ant_Gain+DL_UE_Ant_Gain-DL_RSRP (Equation 1)

[0161] UL_Path_Loss=UL_UE_Power+LUL_UE_Ant_Gain+UL_gNB_Ant_Gain-UL_RSRP (Equation 2)

[0162] Reading from left to right, the parameters of Equation 1 represent Figure 6 DL path loss 1012, DL gNB TX power 1002, DL gNB antenna gain 1006, DL UE antenna gain 1020, and DL RSRP 1026. Reading from left to right, the parameters in Equation 2 represent Figure 6UL path loss 1014, UL UE TX power 1028, UL UE antenna gain 1022 and UL gNB antenna gain 1008.

[0163] Figure 6 Also depicted are known values at the UE 1016 and unknown values at the UE 1018 .

[0164] Assuming channel reciprocity, the DL path loss 1012 and the UL path loss 1014 are equal, and thus the above equation reduces to:

[0165] UL_RSRP=DL_RSRP+gNB_Ant_Delta_Gain-DL_gNB_Power+UL_UE_Power+UE_Ant_Delta_Gain (Equation 3)

[0166] in:

[0167] gNB_Ant_Delta_Gain=UL_gNB_Ant_Gain-DL_gNB_Ant_Gain (Equation 4)

[0168] UE_Ant_Delta_Gain=UL_UE_Ant_Gain-DL_UE_Ant_Gain (Equation 5)

[0169] UE 110-1 may now choose to adjust the UL beam configuration and potentially the UL TX power level to satisfy the link budget of both gNBs, as long as the calculated UL_RSRP > UL_RSRP_Target exists for each gNB. The term UL_RSRP_Target corresponds to Figure 6 UL RSRP target 1004.

[0170] Reading from left to right after the UL_RSRP term, the parameters of Equation 3 represent Figure 6 DL RSRP 1026, gNB antenna UL / DL incremental gain 1010, DL gNB TX power 1002, UL UE TX power 1028, and UE antenna UL / DL incremental gain 1024. Reading from left to right, the parameters in Equation 4 represent Figure 6 The gNB antenna UL / DL incremental gain is 10 10, the UL gNB antenna gain is 1008, and the DL gNB antenna gain is 1006. Reading from left to right, the variables in Equation 5 represent Figure 6 UE antenna UL / DL incremental gain 1024, UL UE antenna gain 1022 and DL UE antenna gain 1020.

[0171] UE->Serving gNB: UE 110-1 reports the updated SRS configuration to serving gNB 170-3 and continues Figure 4 The multi-RTT measurement process is shown.

[0172] Figure 7 is a diagram showing an example estimation of the number or ID of SRSs. The LMF collects the SRS updated configuration from each UE and after calculating the UE position, it fills the following table (a portion of which is shown as Figure 7 Table 702):

[0173] UE ID Location speed SRS ID UE 1 [x, y, z]_1 V1 2、3、4 UE 1 [x, y, z]_2 V2 2、5、6 ... ... ... ... UE P [x, y, z]_p vp 1、3、10

[0174] For each UE (in the table above, there are P UEs), the LMF can then use parameters such as position, velocity and / or SRS to use a position prediction algorithm 704 and estimate the future UE position (see Figure 7 The position prediction algorithm may use other parameters besides position, velocity, and SRS, such as SINR, azimuth, UE form factor, channel estimate, etc., so the list of parameters mentioned here is non-exhaustive. The LMF may use this estimate of the future UE position to predict 706 the number of SRSs that the UE may need.

[0175] Figure 7 An embodiment of this method is depicted in FIG. The position predictor 704 may be implemented by, for example, an extended Kalman filter (EKF) or a neural network (NN), while the SRS set size predictor 706 may be implemented as, for example, a NN or a decision forest. Alternatively or additionally, the latter predictor may output a list of SRS IDs that the UE may use (e.g., Figure 7 "SRSID List" shown).

[0176] For multi-panel UEs, during DL PRS scanning, the UE may scan its antenna panels during this process. Figure 8 is a diagram showing an example of UE panel selection for UL SRS transmission. Figure 8 , the antenna panels of UE 110-1 are shown as items 199-1, 199-2, and 199-3. In many cases, the panels on one side of the UE (such as panel 199-1) have similar performance to the panels on the adjacent side of the UE (such as panel 199-2). Therefore, combining UL SRS transmissions can help further reduce the number of UL SRSs. This is in Figure 8 Shown in.

[0177] exist Figure 8In the example shown, UE 110-1 may use two different panels (ie, panel 199-1 and panel 199-2) for UL SRS transmission. The angle between the SRS aiming directions is Rather small, and a single UL SRS (instead of SRS 1 and SRS 2) is sufficient to cover two gNBs (gNB 1 and gNB 2).

[0178] Therefore, if the angle between the two UL transmissions is below a threshold, UE 110-1 may decide to combine the UL SRS into a single UE panel.

[0179] refer to Figure 8 In the example, two situations may occur:

[0180] In the first case, the UE panel beams (beams 198-1 and 198-2) partially overlap, and the DL PRS from both gNBs is received by both UE antenna panels 199-1 and 199-2. In this case, UE 110-1 does not need to adjust the UL beamwidth or steering angle, but can decide to select the antenna panel with the highest DL RSRP for UL SRS transmission and use only one SRS for both gNBs. The UE RX-TX report can use the panel used for SRS transmission as a reference (i.e., use the DL PRS TOA from that panel).

[0181] In the second scenario, although the angle at UE 110-1 is smaller, the panel beams do not overlap, so the DL PRS from gNB1 and gNB2 are only received on UE panels 199-1 and 199-2, respectively. UE 110-1 can now decide, based on the angle being less than a threshold and link budget assessment, to widen the UL beamwidth on one antenna panel and optionally tilt the beam (such as beam 198-1) to cover both gNBs and thereby transmit only one SRS to both gNBs. In this scenario, one DL PRS TOA can come from an unused panel in the UL (such as panel 199-2), but the incremental distance is smaller because the beams are steered in similar directions. This scenario is most likely to occur when the UE uses narrow beams to maintain the DL budget. Therefore, widening the UL beam is only possible if the gNB provides higher UL gain than the DL. This can be signaled in the assistance information described above.

[0182] The main advantages and technical effects of the method described herein are reduced resource overhead, reduced complexity, reduced interference, and UE power savings. The described method allows the UE to transmit fewer SRS-P resources to complete the multi-RTT process by determining wasted overhead and signaling to the network. This reduction in SRS-P resources makes the method less complex from a network perspective and enables a configuration that requires fewer resources to be reserved. The UE also saves power by transmitting fewer SRS-Ps. These advantages and technical effects do not reduce positioning accuracy because the same cell is capable of measuring RTT.

[0183] Figure 9 9 is an example apparatus 900 that can be implemented in hardware and configured to implement SRS for reducing positioning resource overhead in multi-RTT based on the examples described herein. Apparatus 900 includes a processor 902, at least one non-transitory memory 904 including computer program code 905, wherein the at least one memory 904 and the computer program code 905 are configured to, together with the at least one processor 902, cause the apparatus to implement processes, components, modules, or functions (collectively, 906) for reducing positioning resource overhead in multi-RTT. Apparatus 900 optionally includes a display and / or I / O interface 908 that can be used to display aspects or status of the methods described herein (e.g., while the methods are being performed or at a later time). Apparatus 900 includes one or more network (NW) interfaces (I / Fs) 910. NW I / Fs 910 can be wired and / or wireless and communicate over the Internet / other network(s) via any communication technology. The NW I / F(s) 910 may include one or more transmitters and one or more receivers.

[0184] Apparatus 900 may be UE 110, RAN node 170, or network element(s) 190. Thus, processor 902 may correspond to processor(s) 120, processor(s) 152, or processor(s) 175, memory 904 may correspond to memory(s) 125, memory(s) 155, or memory(s) 171, computer program code 905 may correspond to computer program code 123, module 140-1, module 140-2, computer program code 153, module 150-1, module 150-2, or computer program code 173, and NW I / F(s) 910 may correspond to N / WI / F(s) 161 or N / WI / F(s) 180. Alternatively, apparatus 900 may not correspond to any of UE 110, RAN node 170, or network element(s) 190 (e.g., apparatus 900 may be a remote device or a cloud device).

[0185] It should also be understood that throughout the description, reference numerals 110-"x", 170-"x", and 190-"x") correspond to Figure 1 The actual project or project variant comprises UE 110, RAN node 170 and (multiple) network elements 190. For example, Figure 4 The LMF190-1 can be or implement Figure 1 The functionality of the network element(s) 190.

[0186] References to "computers," "processors," and the like should be understood to include not only computers having different architectures (such as single / multi-processor architectures and sequential (von Neumann) / parallel architectures), but also specialized circuits such as field programmable gate arrays (FPGAs), application specific circuits (ASICs), signal processing devices, and other processing circuit systems. References to computer programs, instructions, code, and the like should be understood to encompass software for programmable processors or firmware, such as the programmable content of a hardware device, whether instructions for a processor or configuration settings for a fixed-function device, gate array, or programmable logic device.

[0187] Figure 10 is an example method 1050 for implementing SRS for positioning resource overhead reduction in multi-RTT based on example embodiments described herein. At 1052, the method includes receiving an initial configuration of a plurality of sounding reference signals for positioning resources. At 1054, the method includes measuring downlink positioning reference signals received from one or more cells. At 1056, the method includes determining one or more transmission beams based on a receive beam for reception of downlink positioning reference signals from the one or more cells. At 1058, the method includes wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning. At 1060, the method includes transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams. The method 1000 may be performed by a system such as Figure 1 Although method 1050 refers to SRS, method 1000 can be applied to any UL reference signal used for positioning. This is true for the methods generally described herein.

[0188] Figure 11Another example method 1100 for implementing SRS for positioning resource overhead reduction in multi-RTT based on example embodiments described herein. At 1102, the method includes transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration. At 1104, the method includes receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource. The method 1100 may be performed by, for example, Figure 1 The RAN node 170 and other radio nodes are used to perform.

[0189] Figure 12

[0014] Another example method 1200 for implementing SRS with reduced positioning resource overhead in multi-RTT based on example embodiments described herein. At 1202, the method includes providing a multi-cell round trip time positioning request for one or more cells. At 1204, the method includes receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request. At 1206, the method includes receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource. At 1208, the method includes transmitting the updated sounding reference signal for positioning configuration to at least one radio node. The method 1200 may be performed by, for example, Figure 1 Method 1200 may also be performed by a location management function of a network element such as network element 190. Figure 1 The RAN node 170 and other radio nodes are used to perform.

[0190] An example method includes: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam used for receiving the downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0191] The method may further include, wherein the determining of the one or more beams comprises identifying a common transmission beam for a plurality of cells representing beam overlap.

[0192] The method may further include, wherein the determining of the one or more beams comprises identifying beam overlap in a spatial domain.

[0193] The method may further include, wherein the determining comprises using an uplink beam or beamwidth that is different than that used for reception of the downlink positioning reference signal.

[0194] The method may further comprise receiving auxiliary information comprising parameters for use in a link budget calculation for use in the determination of the one or more transmission beams; and calculating a link budget based on the received auxiliary information parameters; wherein the determination of the one or more transmission beams involves determining beam overlap.

[0195] The method may further include wherein the calculating is based on at least one of: a beamforming gain of a downlink positioning reference signal resource; a steering angle; a received power of the downlink positioning reference signal; a received minimum requested received power; or local knowledge of the minimum requested received power.

[0196] The method may further include, wherein the assistance information is received from at least one of a base station or a location management function.

[0197] The method may also include scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; and combining uplink sounding reference signal resources into a single antenna panel in response to an angle between at least two uplink transmissions being below a threshold.

[0198] The method may further include, wherein the determining includes adjusting the uplink beam configuration and the uplink power level to meet the link budget in response to the calculated uplink reference signal received power being greater than a target uplink reference signal received power of at least one of the one or more cells.

[0199] The method may further include, wherein the reducing of the at least one beam resource comprises widening or tilting the at least one beam to eliminate the need to use a sounding reference signal for positioning resources.

[0200] An example method includes transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource.

[0201] The method may further include receiving and providing a multi-cell round trip time positioning request for one or more cells; providing an initial sounding reference signal for positioning configuration; and transmitting the updated sounding reference signal for positioning configuration to neighboring radio nodes and / or a location management function.

[0202] The method may further comprise providing assistance information comprising parameters for use in link budget calculation for use in determining the reduction of the at least one beam resource.

[0203] The method may further include, wherein the assistance information comprises at least one of: a radio node downlink power; a radio node UL / DL incremental antenna gain; or a minimum target uplink reference signal received power.

[0204] The method may further include receiving an initial sounding reference signal for positioning configuration.

[0205] An example method includes providing a multi-cell round trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node.

[0206] The method may further include tracking the required number of sounding reference signals for positioning the resources based on at least one of a location, mobility, or trajectory of a user equipment used to configure the required number of sounding reference signals for positioning the resources.

[0207] The method may further include: estimating a future location of the user equipment using a location prediction algorithm; and predicting a number of sounding reference signals for positioning resources that may be required by the user equipment based on the predicted future location.

[0208] The method may further include, wherein the predicting comprises outputting a list of sounding reference signals that the user equipment can use for positioning an identifier.

[0209] The method may further include providing the user equipment with a minimum requested received power as a threshold for determining whether the link budget is sufficient.

[0210] An example apparatus comprises at least one processor; and at least one non-volatile memory comprising computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam for receiving the downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0211] The apparatus may further include, wherein the determining of the one or more beams comprises identifying a common transmission beam for a plurality of cells representing beam overlap.

[0212] The apparatus may further include, wherein the determining of the one or more beams comprises identifying beam overlap in a spatial domain.

[0213] The apparatus may further include, wherein the determining comprises using an uplink beam or beamwidth that is different than that used for reception of the downlink positioning reference signal.

[0214] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: receiving auxiliary information comprising parameters for use in link budget calculation for use in the determination of the one or more transmission beams; and calculating a link budget based on the received auxiliary information parameters; wherein the determination of the one or more transmission beams involves determining beam overlap.

[0215] The apparatus may further include wherein the calculating is based on at least one of: a beamforming gain of a downlink positioning reference signal resource; a steering angle; a received power of the downlink positioning reference signal; a received minimum requested received power; or local knowledge of the minimum requested received power.

[0216] The apparatus may further include, wherein the assistance information is received from at least one of a base station or a location management function.

[0217] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: scanning a plurality of antenna panels to identify whether a shared beam can be used for a plurality of target cells; and combining uplink sounding reference signal resources into a single antenna panel in response to an angle between at least two uplink transmissions being below a threshold.

[0218] The apparatus may further include, wherein the determining comprises adjusting an uplink beam configuration and an uplink power level to meet a link budget in response to the calculated uplink reference signal received power being greater than a target uplink reference signal received power for at least one of the one or more cells.

[0219] The apparatus may further include, wherein the reducing of the at least one beam resource comprises widening or tilting at least one beam to eliminate the need to use a sounding reference signal for positioning resources.

[0220] An example apparatus comprises at least one processor; and at least one non-volatile memory comprising computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource.

[0221] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: receiving and providing a multi-cell round trip time positioning request for one or more cells; providing an initial sounding reference signal for positioning configuration; and transmitting the updated sounding reference signal for positioning configuration to neighboring radio nodes and / or a location management function.

[0222] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: providing assistance information comprising parameters for use in link budget calculations and for use in determining the reduction of the at least one beam resource.

[0223] The apparatus may further include, wherein the assistance information comprises at least one of: a radio node downlink power; a radio node UL / DL incremental antenna gain; or a minimum target uplink reference signal received power.

[0224] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: receiving an initial sounding reference signal for positioning configuration.

[0225] An example apparatus comprises at least one processor; and at least one non-volatile memory comprising computer program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the apparatus to at least perform: providing a multi-cell round trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal configuration for positioning, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node.

[0226] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: tracking the number of sounding reference signals required for positioning resources based on at least one of a location, mobility, or trajectory of a user equipment used to configure the number of sounding reference signals required for positioning resources.

[0227] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: estimating a future position of a user equipment using a position prediction algorithm; and predicting a number of sounding reference signals for positioning resources that the user equipment may need based on the predicted future position.

[0228] The apparatus may further include, wherein the predicting comprises outputting a list of sounding reference signals that the user equipment can use for positioning an identifier.

[0229] The apparatus may further include, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the apparatus to at least perform: providing a minimum requested received power for a user equipment as a threshold for determining whether a link budget is sufficient.

[0230] An exemplary non-transitory program storage device readable by a machine is provided, the non-transitory program storage device tangibly embodying an instruction program executable by the machine for performing operations, the operations comprising: receiving an initial configuration of multiple sounding reference signals for positioning resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmission beams based on a receive beam for receiving the downlink positioning reference signals from the one or more cells; wherein the determination of the one or more transmission beams includes a reduction of at least one beam resource associated with the sounding reference signal for positioning; and transmitting an updated sounding reference signal for positioning configuration having information about the determined one or more transmission beams.

[0231] The non-transitory program storage device may further include, wherein the determining of the one or more beams comprises identifying a common transmission beam for a plurality of cells representing beam overlap.

[0232] The non-transitory program storage device may also include, wherein the determining of the one or more beams comprises identifying beam overlap in a spatial domain.

[0233] The non-transitory program storage device may further include, wherein the determining comprises using an uplink beam or beamwidth that is different than that used for reception of the downlink positioning reference signal.

[0234] The non-transitory program storage device may also include, wherein the operations further include: receiving auxiliary information, the auxiliary information including parameters for use in a link budget calculation and for use in the determination of the one or more transmission beams; and calculating a link budget based on the received auxiliary information parameters; wherein the determination of the one or more transmission beams involves determining beam overlap.

[0235] The non-transitory program storage device may also include, wherein the calculation is based on at least one of: a beamforming gain of a downlink positioning reference signal resource; a steering angle; a received power of the downlink positioning reference signal; a received minimum requested received power; or local knowledge of the minimum requested received power.

[0236] The non-transitory program storage device may further include, wherein the assistance information is received from at least one of a base station or a location management function.

[0237] The non-transitory program storage device may also include, wherein the operations further include: scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; and in response to an angle between at least two uplink transmissions being below a threshold, combining uplink sounding reference signal resources into a single antenna panel.

[0238] The non-transitory program storage device may also include, wherein the determining includes adjusting the uplink beam configuration and the uplink power level to meet the link budget in response to the calculated uplink reference signal received power being greater than a target uplink reference signal received power of at least one of the one or more cells.

[0239] The non-transitory program storage device may further include, wherein the reducing of the at least one beam resource comprises widening or tilting the at least one beam to eliminate the need to use a sounding reference signal for positioning resources.

[0240] An exemplary non-transitory program storage device readable by a machine, the non-transitory program storage device tangibly embodying a program of instructions executable by the machine for performing operations comprising: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; and receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource.

[0241] The non-transitory program storage device may also include, wherein the operations further include: receiving and providing a multi-cell round trip time positioning request for one or more cells; providing an initial sounding reference signal for positioning configuration; and transmitting the updated sounding reference signal for positioning configuration to neighboring radio nodes and / or location management functions.

[0242] The non-transitory program storage device may further include, wherein the operations further include providing assistance information including parameters for use in link budget calculations for use in determining the reduction of the at least one beam resource.

[0243] The non-transitory program storage device may further include, wherein the assistance information comprises at least one of: radio node downlink power; radio node UL / DL incremental antenna gain; or minimum target uplink reference signal received power.

[0244] The non-transitory program storage device may further include, wherein the operations further comprise receiving an initial sounding reference signal for positioning configuration.

[0245] An exemplary non-transitory program storage device readable by a machine is provided, the non-transitory program storage device tangibly embodying an instruction program executable by the machine for performing operations, the operations comprising: providing a multi-cell round-trip time positioning request for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round-trip time positioning request; receiving an updated sounding reference signal for positioning configuration, wherein the updated sounding reference signal for positioning configuration is based on a reduction of at least one beam resource; and transmitting the updated sounding reference signal for positioning configuration to at least one radio node.

[0246] The non-transitory program storage device may further include, wherein the operation further includes: tracking the number of sounding reference signals required for positioning resources based on at least one of the location, mobility or trajectory of the user equipment used to configure the number of sounding reference signals required for positioning resources.

[0247] The non-transitory program storage device may further include, wherein the operations further include: estimating a future location of the user equipment using a location prediction algorithm; and predicting a number of sounding reference signals for positioning resources that the user equipment may need based on the predicted future location.

[0248] The non-transitory program storage device may further include, wherein the predicting comprises outputting a list of sounding reference signals that the user equipment can use for positioning an identifier.

[0249] The non-transitory program storage device may further include, wherein the operations further include providing a minimum requested received power for the user equipment as a threshold for determining whether the link budget is sufficient.

[0250] It should be understood that the above description is illustrative only. Those skilled in the art may devise various alternatives and modifications. For example, the features recited in the various dependent claims may be combined with one another in any suitable combination. Furthermore, features from the different embodiments described above may be selectively combined to form new embodiments. Therefore, this specification is intended to encompass all such alternatives, modifications, and variations that fall within the scope of the appended claims.

Claims

1. A method for communication, comprising: receiving an initial configuration of a plurality of sounding reference signals for locating resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmit beams based on receive beams used for receiving the downlink positioning reference signal from the one or more cells; wherein said determining of said one or more transmission beams comprises: a reduction of at least one beam resource associated with a sounding reference signal used for positioning; Scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; In response to an angle between at least two uplink transmissions being below a threshold, combining uplink sounding reference signal resources into a single antenna panel to reduce the at least one beam resource associated with the sounding reference signal used for positioning; and An updated sounding reference signal for positioning configuration is transmitted having information about the determined one or more transmission beams associated with a reduction in the at least one beam resource associated with the sounding reference signal for positioning.

2. The method of claim 1 , wherein the determining of the one or more beams comprises: The identification represents a common transmission beam for multiple cells where the beams overlap.

3. The method of claim 1 , wherein the determining of the one or more beams comprises: Identify beam overlap in the spatial domain.

4. The method of claim 1 , wherein the determining comprises: A different uplink beam or beamwidth is used than that used for reception of the downlink positioning reference signal.

5. The method according to claim 1, further comprising: receiving assistance information comprising parameters for use in a link budget calculation for use in said determining of said one or more transmit beams; as well as calculating a link budget based on the received auxiliary information parameters; Wherein said determining of said one or more transmission beams involves determining beam overlap.

6. A device for communication, comprising: at least one processor; as well as at least one non-transitory memory including computer program code; wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform: receiving an initial configuration of a plurality of sounding reference signals for locating resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmit beams based on receive beams used for receiving the downlink positioning reference signal from the one or more cells; wherein said determining of said one or more transmission beams comprises: a reduction of at least one beam resource associated with a sounding reference signal used for positioning; Scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; In response to an angle between at least two uplink transmissions being below a threshold, combining uplink sounding reference signal resources into a single antenna panel to reduce the at least one beam resource associated with the sounding reference signal used for positioning; and An updated sounding reference signal for positioning configuration is transmitted having information about the determined one or more transmission beams associated with a reduction in the at least one beam resource associated with the sounding reference signal for positioning.

7. The apparatus of claim 6, wherein the determining of the one or more beams comprises: The identification represents a common transmission beam for multiple cells where the beams overlap.

8. The apparatus of claim 6, wherein the determining of the one or more beams comprises: Identify beam overlap in the spatial domain.

9. The apparatus of claim 6, wherein the determining comprises: A different uplink beam or beamwidth is used than that used for reception of the downlink positioning reference signal.

10. The apparatus of claim 6, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: receiving assistance information comprising parameters for use in a link budget calculation for use in said determining of said one or more transmit beams; as well as calculating a link budget based on the received auxiliary information parameters; Wherein said determining of said one or more transmission beams involves determining beam overlap.

11. The apparatus of claim 10, wherein the calculation is based on at least one of: Beamforming gain for downlink positioning reference signal resources; Steering angle; the received power of the downlink positioning reference signal; The minimum requested receive power received; or Local knowledge of the minimum requested received power.

12. The apparatus of claim 10, wherein the assistance information is received from at least one of a base station or a location management function.

13. The apparatus of claim 10, wherein the determining comprises: In response to the calculated uplink reference signal received power being greater than a target uplink reference signal received power for at least one of the one or more cells, an uplink beam configuration and an uplink power level are adjusted to meet a link budget.

14. The apparatus of claim 6, wherein the reduction of the at least one beam resource comprises: At least one beam is widened or tilted to eliminate the need to use a sounding reference signal for positioning resources.

15. An apparatus for communication, comprising: at least one processor; as well as at least one non-transitory memory including computer program code; wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform: transmitting a downlink positioning reference signal to be used in a positioning method involving a sounding reference signal for positioning configuration; as well as receiving an updated sounding reference signal for positioning configuration having information about one or more transmission beams, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource, The one or more transmission beams are associated with a reduction of the at least one beam resource associated with the sounding reference signal used for positioning, and the reduction is achieved by: scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; and in response to an angle between at least two uplink transmissions being lower than a threshold, combining uplink sounding reference signal resources into a single antenna panel to reduce the at least one beam resource associated with the sounding reference signal used for positioning.

16. The apparatus of claim 15, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: receiving and providing multi-cell round trip time location requests for one or more cells; Providing an initial sounding reference signal for positioning configuration; and The updated sounding reference signal for positioning configuration is transmitted to neighboring radio nodes and / or a location management function.

17. The apparatus of claim 15, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: Assistance information is provided, the assistance information comprising parameters for use in a link budget calculation for use in determining the reduction of the at least one beam resource.

18. The apparatus according to claim 17, wherein the auxiliary information comprises at least one of the following: Radio node downlink power; Radio node UL / DL incremental antenna gain; or Minimum target uplink reference signal received power.

19. The apparatus of claim 15, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: An initial sounding reference signal for positioning configuration is received.

20. An apparatus for communication, comprising: at least one processor; as well as at least one non-transitory memory including computer program code; wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to at least perform: Provides multi-cell round trip time location requests for one or more cells; receiving an initial sounding reference signal for positioning configuration based on the multi-cell round trip time positioning request; receiving an updated sounding reference signal for positioning configuration having information about one or more transmission beams, wherein the updated sounding reference signal for positioning configuration is based on a reduction in at least one beam resource; as well as transmitting said updated sounding reference signal for positioning configuration to at least one radio node, The one or more transmission beams are associated with a reduction of the at least one beam resource associated with the sounding reference signal used for positioning, and the reduction is achieved by: scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; and in response to an angle between at least two uplink transmissions being lower than a threshold, combining uplink sounding reference signal resources into a single antenna panel to reduce the at least one beam resource associated with the sounding reference signal used for positioning.

21. The apparatus of claim 20, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: The required number of sounding reference signals for positioning resources is tracked based on at least one of a location, mobility, or trajectory of a user equipment used to configure the required number of sounding reference signals for positioning resources.

22. The apparatus of claim 20, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: Using a location prediction algorithm to estimate the future location of the user device; and Based on the predicted future position, the number of sounding reference signals for positioning resources that the user equipment may need is predicted.

23. The apparatus of claim 22, wherein the prediction comprises: A list of sounding reference signals for positioning identifiers that can be used by the user equipment is output.

24. The apparatus of claim 20, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus to at least perform: A minimum requested received power is provided to the user equipment as a threshold for determining whether the link budget is sufficient.

25. A non-transitory program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine for performing operations comprising: receiving an initial configuration of a plurality of sounding reference signals for locating resources; measuring downlink positioning reference signals received from one or more cells; determining one or more transmit beams based on receive beams used for receiving the downlink positioning reference signal from the one or more cells; wherein said determining of said one or more transmission beams comprises: a reduction of at least one beam resource associated with a sounding reference signal used for positioning; Scanning multiple antenna panels to identify whether a shared beam can be used for multiple target cells; In response to an angle between at least two uplink transmissions being below a threshold, combining uplink sounding reference signal resources into a single antenna panel to reduce the at least one beam resource associated with the sounding reference signal used for positioning; and An updated sounding reference signal for positioning configuration is transmitted having information about the determined one or more transmission beams associated with a reduction in the at least one beam resource associated with the sounding reference signal for positioning.

26. The non-transitory program storage device of claim 25, wherein the determining of the one or more beams comprises: The identification represents a common transmission beam for multiple cells where the beams overlap.

27. The non-transitory program storage device of claim 25, wherein the determining of the one or more beams comprises: Identify beam overlap in the spatial domain.

28. The non-transitory program storage device of claim 25, wherein said determining comprises: A different uplink beam or beamwidth is used than that used for reception of the downlink positioning reference signal.

29. The non-transitory program storage device of claim 25, the operations further comprising: receiving assistance information comprising parameters for use in a link budget calculation for use in said determining of said one or more transmit beams; as well as Calculating a link budget based on the received auxiliary information parameters; Wherein said determining of said one or more transmission beams involves determining beam overlap.

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