WO2024093380A1

WO2024093380A1 - Sidelink positioning with changes in coverage scenario

Info

Publication number: WO2024093380A1
Application number: PCT/CN2023/108760
Authority: WO
Inventors: Luning Liu; Jing HAN; Jie Hu; Haiming Wang; Lihua Yang
Original assignee: Lenovo (Beijing) Limited
Priority date: 2023-07-21
Filing date: 2023-07-21
Publication date: 2024-05-10

Abstract

Various aspects of the present disclosure relate to user equipments (UEs), a network device, processors for wireless communication, methods, and non-transitory computer readable media for sidelink positioning with changes in coverage scenario. In an aspect, a first UE obtains a change of network coverage state of a UE. The UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE. The first UE transmits, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE. In this way, the continuity of the positioning service may be guaranteed.

Description

SIDELINK POSITIONING WITH CHANGES IN COVERAGE SCENARIO

TECHNICAL FIELD

The present disclosure relates to wireless communications, and more specifically to user equipments (UEs) , a network device, processors for wireless communication, methods, and non-transitory computer readable media for sidelink positioning with changes in coverage scenario.

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication devices, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

In sidelink (SL) positioning, dynamic topology caused by the mobility of involved UEs may bring challenges for positioning performance. Release 18 has agreed to support in-coverage (IC) , partial coverage (PC) and out-of-coverage (OOC) scenarios for SL positioning. Specifically, an IC scenario refers to the case where all the involved UEs are inside the network, a PC scenario means that at least one involved UE remains inside the network coverage but other UEs are outside the network coverage, and an OOC scenario refers to the case where all involved UEs are outside the network coverage. The change of coverage scenario is one of the mobility-related issues in SL positioning, including from OOC to PC, from PC to OOC, from IC to PC, and from PC to IC. Enhancements on solutions in SL positioning with changes in coverage scenario are still needed.

SUMMARY

The present disclosure relates to UEs, a network device, processors for wireless communication, methods, and non-transitory computer readable media for sidelink positioning with changes in coverage scenario. Embodiments of the disclosure can guarantee the continuity of the positioning service when the coverage scenario is changed.

In a first aspect of the solution, a first UE obtains a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmits, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE. Through the proposed solution, the first UE may inform the third UE or the network device about the change of network coverage state of the involved UE associated with a first positioning operation for the first UE, which enables the third UE or the network device to take actions to guarantee the continuity of the positioning service.

In some implementations of the method and apparatuses described herein, the UE is the first UE. Some implementations of the method and apparatuses described herein may further include: transmit, to the network device or the third UE, assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

In some implementations of the method and apparatuses described herein, wherein the assistance information comprises one of the following: mobility information of the first UE; a Uu link quality of the first UE; or positioning request-related information.

In some implementations of the method and apparatuses described herein, wherein transmitting the indication of the change of network coverage state of the UE comprises: in the case that the first UE enters network coverage for a pre-defined time window, transmitting, to the third UE or the network device, an indication that the network coverage state of the first UE changes to be in-coverage.

Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the first UE changes to be in-coverage, transmit, to the network device, a request for a network device-dependent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-independent. Some implementations of the method and apparatuses described herein may further include: in the case that the first UE is in network coverage, receive, from the network device, an indication of a network device-independent positioning operation; and continue the first positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-independent. Some implementations of the method and apparatuses described herein may further include: in the case that the first UE is in network coverage, receive, from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and transmit, to the network device, the positioning request-related information or the positioning session-related information.

Some implementations of the method and apparatuses described herein may further include: in the case that the first UE is in network coverage, receive, from the network device, an indication of operations to be performed by the third UE or an indication of releasing a server function; and transmit, to the third UE, the indication of operations to be performed by the third UE or the indication of releasing a server function.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the UE changes to be out-of-network coverage, determine respective network coverage states of the at least one second UE.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: in the case that the at least one second UE and the first UE are out of network coverage, determine a third UE for a network device-independent positioning operation for the first UE; and perform the network device-independent positioning operation with the third UE.

In some implementations of the method and apparatuses described herein, the first UE acts as the third UE for the network device-independent positioning operation.

Some implementations of the method and apparatuses described herein may further include: transmit, to the at least one second UE, information of the third UE for the network device-independent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: in the case that the at least one second UE and the first UE are out of network coverage, determine an in-coverage UE as a relay UE for communication between the first UE and the network device; and transmit, to the network device via the in-coverage UE, positioning result or measurement data associated with the first UE.

Some implementations of the method and apparatuses described herein may further include: in the case that the in-coverage UE is not determined for a time period, abort a positioning session.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the first UE is in network coverage, the UE is the second UE. Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the second UE changes to be out-of-network coverage, reselect a second UE.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the UE is the first UE. Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the first UE changes to be out-of-coverage, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; and in the case that the network device-independent positioning operation is determined, transmit, to the network device via an in-coverage UE, an indication of the network device-independent positioning operation; or in the case that the network device-dependent positioning operation is determined, transmit, to the network device via an in-coverage UE, a request for the network device-dependent positioning operation and assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE by the network device.

In some implementations of the method and apparatuses described herein, the assistance information comprises mobility information of the first UE.

In some implementations of the method and apparatuses described herein, the network coverage state of the first UE changes to be out-of-coverage, and the indication of the change of network coverage state is transmitted to the network device via an in-coverage UE.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: receive, from the network device via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage. Some implementations of the method and apparatuses described herein may further include: in the case that a network device-independent positioning operation is determined for the first UE, determine a third UE for the network device-independent positioning operation.

Some implementations of the method and apparatuses described herein may further include: transmit, to the third UE for the network device-independent positioning operation, one of the following: positioning request-related information, positioning session-related information associated with the first positioning operation, or an indication of operations to be performed by the third UE in the network device-independent positioning operation.

In some implementations of the method and apparatuses described herein, the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of the at least one second UE; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

In some implementations of the method and apparatuses described herein, the positioning request-related information or the positioning session-related information is transmitted in a RequestAssistanceData message.

In some implementations of the method and apparatuses described herein, the first UE is out of network coverage and an in-coverage UE is a relay UE for communication between the first UE and the network device prior to obtaining the change of network coverage state of the first UE. Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the first UE changes to be in-coverage, transmit, to the in-coverage UE, an indication of releasing a relay function.

In some implementations of the method and apparatuses described herein, the in-coverage UE is a second UE among the at least one second UE.

In some implementations of the method and apparatuses described herein, determining the change of network coverage state of the second UE comprises: receiving, from the second UE, an indication of the change of network coverage state of the second UE.

In a second aspect of the solution, a second UE determine a change of network coverage state of the second UE; and transmit an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device. Through the proposed solution, the second UE may inform the first UE, the third UE or the network device about the change of network coverage state of the second UE associated with a first positioning operation for the first UE, which enables the first UE, the third UE or the network device to take actions to guarantee the continuity of the positioning service.

In some implementations of the method and apparatuses described herein, transmitting the indication of the change of network coverage state of the second UE comprises one of the following: transmitting an indication that the network coverage state of the second UE changes to be in-coverage in the case that the second UE enters network coverage for a pre-defined time window; or transmitting, to the first UE, an indication that the network coverage state of the second UE changes to be out-of-coverage in the case that the second UE moves out of network coverage.

Some implementations of the method and apparatuses described herein may further include: transmit, to the network device or the third UE, assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

In some implementations of the method and apparatuses described herein, the assistance information comprises one of the following: mobility information of the second UE; a Uu link quality of the second UE; or positioning request-related information.

Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the second UE changes to be in-coverage, transmit, to the network device, a request for a network device-dependent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-independent. Some implementations of the method and apparatuses described herein may further include: in the case that the second UE is in network coverage, receive, from the network device, an indication of a network device-independent positioning operation; and continue the first positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-independent. Some implementations of the method and apparatuses described herein may further include: in the case that the second UE is in network coverage, receive, from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and transmit, to the network device, the positioning request-related information or the positioning session-related information.

Some implementations of the method and apparatuses described herein may further include: in the case that the second UE is in network coverage, receive, from the network device, an indication of operations to be performed by the third UE or an indication of releasing a server function; and transmit, to the third UE, the indication of operations to be performed by the third UE or the indication of releasing a server function.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: receive, from the first UE, information of a third UE for a network device-independent positioning operation for the first UE; and perform the network device-independent positioning operation with the third UE and the first UE.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, and the second UE is in network coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the first UE, an indication of a network device-independent positioning operation; and transmit, to the network device, the indication of the network device-independent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, and the second UE is in network coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the first UE, a request for a network device-dependent positioning operation and assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE by the network device; and transmit, to the network device, the request for the network device-dependent positioning operation and the assistance information.

In some implementations of the method and apparatuses described herein, wherein the first positioning operation is network device-dependent, the second UE is in network coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the first UE, an indication that the network coverage state of the first UE changes to be out-of-coverage; and transmit, to the network device, the indication that the network coverage state of the first UE changes to be out-of-coverage.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the second UE is in network coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the network device, an indication of a network device-independent positioning operation and positioning request-related information; and transmit, to the first UE, the indication of the network device-independent positioning operation and positioning request-related information.

In some implementations of the method and apparatuses described herein, the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of at least one second UE associated with the first positioning operation; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

In some implementations of the method and apparatuses described herein, the second UE is in network coverage as a relay UE for communication between the first UE and the network device. Some implementations of the method and apparatuses described herein may further include: receive, from the first UE or the network device, an indication of releasing a relay function.

In a third aspect of the solution, a third UE receives one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information. In the case that the indication of the change of network coverage state of the UE is received, the third UE determines a network device-dependent positioning operation or a network device-independent positioning operation for the first UE. In the case that the positioning request-related information or the positioning session-related information is received, the third UE performs a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information. Through the proposed solution, the third UE may be aware of the change of network coverage state of the involved UE associated with a first positioning operation for the first UE, which enables the third UE to take actions to guarantee the continuity of the positioning service. Alternatively, the third UE may be able to perform the second positioning operation based on information related to the first positioning operation, which guarantees the continuity of the positioning service.

Some implementations of the method and apparatuses described herein may further include: receive, from the UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Some implementations of the method and apparatuses described herein may further include: receive, from the first UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

In some implementations of the method and apparatuses described herein, the assistance information comprises one of the following: mobility information of the UE; a Uu link quality of the UE; or positioning request-related information.

Some implementations of the method and apparatuses described herein may further include: receive, from the network device or an in-coverage UE, an indication of operations to be performed by the third UE or an indication of releasing a server function; and perform the operations in the case that the indication of the operations is received; or release the server function in the case that the indication of releasing the server function is received.

In some implementations of the method and apparatuses described herein, the positioning request-related information or the positioning session-related information is received in a RequestAssistanceData message. Some implementations of the method and apparatuses described herein may further include: determine an updated configuration for the SL-PRS or an updated measurement configuration, and wherein the second positioning operation is performed based on the updated configuration or the updated measurement configuration.

In some implementations of the method and apparatuses described herein, performing the second positioning operation comprises: receiving measurement data associated with the first UE in a ProvideLocationInformation message; and performing a location calculation for the first UE based on the measurement data.

In a fourth aspect of the solution, a network device receives, from an in-coverage UE, an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determines a network device-dependent positioning operation or a network device-independent positioning operation for the first UE. Through the proposed solution, the network device may be aware of the change of network coverage state of the involved UE associated with a first positioning operation for the first UE, which enables the network device to take actions to guarantee the continuity of the positioning service.

Some implementations of the method and apparatuses described herein may further include: receive, from the in-coverage UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Some implementations of the method and apparatuses described herein may further include: receive, from the in-coverage UE, a request for a network device-dependent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-independent. Some implementations of the method and apparatuses described herein may further include: in the case that the network device-independent positioning operation is determined, transmit, to the in-coverage UE, an indication of the network device-independent positioning operation.

Some implementations of the method and apparatuses described herein may further include: transmit, to the in-coverage UE, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and receive, from the in-coverage UE, the positioning request-related information or the positioning session-related information.

Some implementations of the method and apparatuses described herein may further include: in the case that the network device-dependent positioning operation is determined, determine whether a third UE is needed for the network device-dependent positioning operation; and in the case that a third UE is needed, transmit, to the third UE via the in-coverage UE, an indication of operations to be performed by the third UE; or in the case that no third UE is needed, transmit, to the third UE via the in-coverage UE, an indication of releasing a server function by the third UE.

Some implementations of the method and apparatuses described herein may further include: in the case that the network device-dependent positioning operation is determined, determine one of the following: performing the network device-dependent positioning operation with the at least one second UE; reselecting second UEs for the network device-dependent positioning operation; or aborting a sidelink positioning session and starting a Uu positioning session or a hybrid Uu and PC5 positioning session in the case that the first UE is in network coverage.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent. Some implementations of the method and apparatuses described herein may further include: in the case that the network device-dependent positioning operation is determined and that the first UE is out of network coverage, receive, from the in-coverage UE, positioning result or measurement data associated with the first UE.

Some implementations of the method and apparatuses described herein may further include: in the case that the network device-dependent positioning operation is determined and that the first UE is out of network coverage, determine the in-coverage UE for communication between the first UE and the network device; and in the case that an in-coverage UE is not determined, abort a positioning session.

Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the second UE changes to be out-of-network coverage, reselect a second UE.

Some implementations of the method and apparatuses described herein may further include: in the case that the network device does not receive responses from the second UE for a period of time, perform one of the following: reselecting a second UE; or aborting a positioning session.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the in-coverage UE, an indication of the network device-independent positioning operation.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, and the network coverage state of the first UE changes to be out-of-coverage. Some implementations of the method and apparatuses described herein may further include: receive, from the in-coverage UE, a request for the network device-dependent positioning operation and assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage. Some implementations of the method and apparatuses described herein may further include: transmit, to the first UE via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.

In some implementations of the method and apparatuses described herein, the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage. Some implementations of the method and apparatuses described herein may further include: in the case that a network device-independent positioning operation is determined for the first UE, determine that a third UE is needed for the network device-independent positioning operation; and transmit, to the first UE via the in-coverage UE, an indication that a third UE is needed.

In some implementations of the method and apparatuses described herein, the first UE is out of network coverage and the in-coverage UE is a relay UE for communication between the first UE and the network device prior to receiving the indication. Some implementations of the method and apparatuses described herein may further include: in the case that the network coverage state of the first UE changes to be in-coverage, transmit, to the in-coverage UE, an indication of releasing a relay function.

In some implementations of the method and apparatuses described herein, the in-coverage UE is a second UE among the at least one second UE or the first UE.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example of a wireless communications system that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure.

FIG. 1B illustrates an example of a wireless communications system that supports SL positioning in an IC scenario in accordance with aspects of the present disclosure.

FIG. 1C illustrates an example of a wireless communications system that supports SL positioning in a PC scenario in accordance with aspects of the present disclosure.

FIG. 1D illustrates an example of another wireless communications system that supports SL positioning in a PC scenario in accordance with aspects of the present disclosure.

FIG. 1E illustrates an example of a wireless communications system that supports SL positioning in an OOC scenario in accordance with aspects of the present disclosure.

FIGS. 2A through 2G illustrate example signaling charts of a communication process that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure.

FIG. 3A illustrates an example of a wireless communications system in a coverage scenario changing from an OOC scenario to a PC scenario in accordance with aspects of the present disclosure.

FIG. 3B illustrates an example of a wireless communications system in a coverage scenario changing from a PC scenario to an OOC scenario in accordance with aspects of the present disclosure.

FIG. 3C illustrates an example of a wireless communications system in a coverage scenario changing from an IC scenario to a PC scenario in accordance with aspects of the present disclosure.

FIG. 3D illustrates an example of a wireless communications system in a coverage scenario changing from a PC scenario to an IC scenario in accordance with aspects of the present disclosure.

FIGS. 4 through 7 illustrate examples of devices that support SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure.

FIGS. 8 through 11 illustrate examples of processors that support SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure.

FIGS. 12 through 20 illustrate flowcharts of methods that support SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure.

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

DETAILED DESCRIPTION

Principles of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below. In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms. In some examples, values, procedures, or apparatuses are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of embodiments. As used herein, the singular forms “a, ” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises, ” “comprising, ” “has, ” “having, ” “includes” and/or “including, ” when used herein, specify the presence of stated features, elements, components and/or the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. For example, the term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The use of an expression such as “A and/or B” can mean either “only A” or “only B” or “both A and B. ” Other definitions, explicit and implicit, may be included below.

As mentioned above, Release 18 has agreed to support IC, PC and OOC scenarios for SL positioning. In RAN2#119-e, it is agreed that for sidelink positioning in-coverage, partial coverage and out-of-coverage scenarios shall be supported. It needs further study if partial coverage case assumes anything about which UEs are in coverage.

3GPP technical requirement (TR) 38.859 provides potential architecture for SL positioning and sidelink positioning solutions as below.

In SL positioning, dynamic topology caused by the mobility of involved UEs may bring challenges for positioning performance. For example, the change of coverage scenario is one of the mobility-related issues in SL positioning, including from OOC to PC, from PC to OOC, from IC to PC and from PC to IC. Solutions for mobility-related SL positioning has not been discussed yet and need to be further studied. In some cases, it’s expected to guarantee the continuity of the positioning service when the coverage scenario is changed. The associated signaling and procedures need to be designed.

In view of the above, embodiments of the present disclosure provide a solution for SL positioning with changes in coverage scenario. In an aspect of the solution, a first UE obtains a change of network coverage state of a UE. The UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE. The first UE transmits, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE. Through the proposed solution, the first UE may inform the third UE or the network device about the change of network coverage state of the involved UE associated with a first positioning operation for the first UE, which enables the third UE or the network device to take actions to guarantee the continuity of the positioning service.

FIG. 1A illustrates an example of a wireless communications system 100 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more network entities 102 (also referred to as network equipment (NE) or network device) , one or more UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20. The wireless communications system 100 may support radio access technologies beyond 5G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN) , a base transceiver station, an access point, a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc. ) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100. In some other implementations, a UE 104 may be mobile in the wireless communications system 100.

The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in FIG. 1A. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment) , as shown in FIG. 1A. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100.

A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102) . In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106) . In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 102 may include one or more of a central unit (CU) , a distributed unit (DU) , a radio unit (RU) , a RAN Intelligent Controller (RIC) (e.g., a Near-Real Time RIC (Near-RT RIC) , a Non-Real Time RIC (Non-RT RIC) ) , a Service Management and Orchestration (SMO) system, or any combination thereof.

An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations) . In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., a layer 3 (L3) , a layer 2 (L2) ) functionality and signaling (e.g., Radio Resource Control (RRC) , service data adaption protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU may be connected to one or more DUs or RUs, and the one or more DUs or RUs may host lower protocol layers, such as a layer 1 (L1) (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160.

Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs) . In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU) .

A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., F1, F1-c, F1-u) , and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface) . In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links.

The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The packet data network 108 may include an application third 118. In some implementations, one or more UEs 104 may communicate with the application third 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application third 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106) .

In the wireless communications system 100, the network entities 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

FIGS. 1B through 1E illustrate examples of a wireless communications system that supports SL positioning in various coverage scenario in accordance with aspects of the present disclosure. In particular, FIG. 1B illustrates an example of a wireless communications system 100-1 that supports SL positioning in an IC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system 100-1 may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A.

For the purpose of discussion, the wireless communications system 100-1 may include a network entity (e.g., a base station) 102, a first UE 104-1, second UEs 104-2, and a location management function (LMF) 106-1. The first UEs 104-1 and the second UEs 104-2 may be in the geographic coverage area 112 of the network entity 102. The LMF 106-1 may be a network element of the core network 106. It should be understood that the LMF 106-1 is merely for illustration. Other types of location servers are also possible. In a SL positioning operation of the first UE 104-1, the first UE may transmit a sidelink positioning reference signal (SL-PRS) to the second UEs 104-2. The second UEs 104-2 may obtain measurement results based on the received SL-PRS and report the measurement results to the LMF 106-1 via the network entity 102. The LMF 106-1 may calculate the location of the first UE 104-1 based on the measurement results. In such positioning operation, the first UE 104-1 acts as a target UE and the second UEs 104-2 act as anchor UEs. In the following description, the first UE 104-1 may also be referred to as a target UE or a T-UE and the second UEs may also be referred to as anchor UEs or A-UEs.

It should be understood that the SL positioning operations in the IC scenario in FIG. 1B is merely for illustration. Other SL positioning operations in the IC scenario are also possible. As an example, there may be a server UE responsible for calculating the location of the target UE 104-1. The server UE may be the target UE, one of the anchor UEs or a UE different from the target UE and the anchor UEs. The LMF 106-1 may receive the calculation results from the server UE. Optionally, the LMF 106-1 may assist the server UE to perform the location calculation. In the following description, the terms “a network device-dependent positioning operation” and “a LMF-dependent positioning operation” may refer to the cases where a location server (such as, a LMF) is involved in the positioning operation and may be used interchangeably. The terms “a network device-independent positioning operation” and “a LMF-independent positioning operation” may be used interchangeably and may refer to the cases where the server UE is responsible for calculating the location of the target UE without LMF-involvement.

FIG. 1C illustrates an example of a wireless communications system 100-2 that supports SL positioning in a PC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system 100-2 may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 1C having the same operations as the steps or components described in FIG. 1B, and detailed description thereof will be omitted.

In the example wireless communications system 100-2, at least one anchor UE 104-2 is in the geographic coverage area 112 of the network entity 102 while the target UE 104-1 and other anchor UEs 104-2 are out of the geographic coverage area 112 of the network entity 102. The anchor UE 104-2 in the geographic coverage area 112 may also be referred to as an IC anchor UE or an anchor IC UE. The anchor UEs 104-2 out of the geographic coverage area 112 may transmit the measurement results to the IC anchor UE 104-2. The IC anchor UE 104-2 may report the measurement results to the LMF 106-1 via the network entity 102. The LMF 106-1 may calculate the location of the target UE 104-1 based on the measurement results.

FIG. 1D illustrates an example of another wireless communications system 100-3 that supports SL positioning in a PC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system 100-3 may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 1D having the same operations as the steps or components described in FIGS. 1B and FIG. 1C, and detailed description thereof will be omitted.

For the purpose of discussion, the wireless communications system 100-3 may include a network entity 102, a target UE 104-1, anchor UEs 104-2, a third UE 104-3 and a LMF 106-1. In the example wireless communications system 100-3, the target UE 104-1 and the third UE 104-3 are in the geographic coverage area 112 of the network entity 102 while the anchor UEs 104-2 are out of the geographic coverage area 112 of the network entity 102. In a SL positioning operation of the target UE 104-1, the anchor UEs 104-2 may obtain measurement results based on the received SL-PRS and report the measurement results to the third UE 104-3. The third UE 104-3 may estimate the position of the target UE 104-1 based on the measurement results and then transmit the estimated positioning result of the target UE 104-1 to the LMF 106-1 via the network entity 102. In such positioning operation, the third UE 104-3 acts as a server UE. In the following description, the third UE 104-3 may also referred to as a server UE or a S-UE. In the following description, the terms “positioning result” and “location result” may be used interchangeably and the terms “position” and “location” may be used interchangeably.

It should be understood that the SL positioning operations in the PC scenario in FIGS. 1C and 1D are merely for illustration. Other SL positioning operations in PC scenario are also possible. As an example, the server UE 104-3 may be out of the geographic coverage area 112 and may transmit the estimated positioning result to the target UE 104-1, which may then forward the estimated positioning result to the LMF 106-1.

FIG. 1E illustrates an example of another wireless communications system 100-4 that supports SL positioning in an OOC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system 100-4 may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 1E having the same operations as the steps or components described in FIGS. 1B through FIG. 1D, and detailed description thereof will be omitted.

In the example wireless communications system 100-4, the target UE 104-1 and the anchor UE 104-2 are out of the geographic coverage area 112 of the network entity 102. The anchor UEs 104-2 may transmit the measurement results to the target UE 104-1. The target UE 104-1 may transmit measurement results to a relay UE 104-4. The relay UE 104-4 is in the geographic coverage area 112 and has a relay function for the communication between the target UE 104-1 and the network entity. The relay UE 104-4 may forward the measurement results to the LMF 106-1 via the network entity 102. The LMF 106-1 may calculate the location of the target UE 104-1 based on the measurement results.

It should be understood that the SL positioning operations in the OOC scenario in FIG. 1E is merely for illustration. Other SL positioning operations in the OOC scenario are also possible. As an example, there may be a server UE responsible for calculating the location of the target UE 104-1. The relay UE 104-4 may forward the calculation results to the LMF 106-1.

Reference is now made to FIG. 2A, which shows an example signaling chart of a communication process 200A that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200A will be described with reference to FIGS. 1A-1E. The process 200A may involve the target UE 104-1 and the server UE 104-3 as illustrated in FIGS. 1B-1E. It is to be understood that the steps and the order of the steps in FIG. 2A are merely for illustration, and not for limitation. It is to be understood that process 200A may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2A, the target UE 104-1 obtains 201 a change of network coverage state of a UE. In some embodiments, the UE is the target UE 104-1. Alternatively, the UE is one of at least one anchor UE 104-2 associated with a first positioning operation for the target UE 104-1. The target UE 104-1 transmits 202 an indication 203 of the change of network coverage state of the UE to a server UE 104-3 associated with the first positioning operation. The server UE 104-3 receives 204 the indication 203 of the change of network coverage state of the UE and determines 205 a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104-1.

In some implementations, the target UE 104-1 may report only changes in its own network coverage state to the server UE 104-3. In such cases, the UE is always the target UE 104-1. In some other implementations, the target UE 104-1 may report changes in network coverage states of involved UEs in its positioning operation. In such cases, the UE may be any one of the target UE 104-1 or an anchor UE 104-2. In some embodiments, the UE may be the anchor UE 104-2. The target UE 104-1 may receive an indication of the change of network coverage state of the anchor UE 104-2 from the anchor UE 104-2, and transmit the indication of the change of network coverage state of the anchor UE 104-2 to the server UE 104-3.

In some embodiments, the UE may be the target UE 104-1. The target UE 104-1 may transmit, to the server UE 104-3, assistance information for the determination 205. The assistance information may include mobility information of the target UE 104-1. Alternatively or additionally, the assistance information may include a Uu link quality of the target UE 104-1. Alternatively or additionally, the assistance information may include positioning request-related information, such as QoS requirement for positioning service of the target UE 104-1.

In some embodiments, after the target UE 104-1 enters network coverage for a pre-defined time window, the target UE 104-1 may report to the server UE 104-3 that its network coverage state changes to be in-coverage. In this way, a ping-pang effect may be avoided.

FIG. 2B shows an example signaling chart of a communication process 200B that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200B will be described with reference to FIGS. 1A-1E. The process 200B may involve the target UE 104-1 as illustrated in FIGS. 1B-1E and a network device 206-1. The network device 206-1 may be a network element of the core network 106 as illustrated in FIG. 1A. For example, the network device 206-1 may be implemented as a location server, such as the LMF 106-1 as illustrated in FIGS. 1B-1E. Other types of location servers are also possible. It is to be understood that the steps and the order of the steps in FIG. 2B are merely for illustration, and not for limitation. Similar reference numerals are used to denote the steps or components described in FIG. 2B having the same operations as the steps or components described in FIG. 2A, and detailed description thereof will be omitted. It is to be understood that process 200B may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2B, the target UE 104-1 obtains 201 a change of network coverage state of a UE. The target UE 104-1 transmits 212 an indication 203 of the change of network coverage state of the UE to the network device 206-1. The network device 206-1 receives 214 the indication 203 of the change of network coverage state of the UE and determines 215 a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104-1.

In some implementations, the target UE 104-1 may report only changes in its own network coverage state to the network device 206-1. In such cases, the UE is always the target UE 104-1. In some other implementations, the target UE 104-1 may report changes in network coverage states of involved UEs in its positioning operation. In such cases, the UE may be any one of the target UE 104-1 or an anchor UE 104-2. In some embodiments, the UE may be the anchor UE 104-2. The target UE 104-1 may receive an indication of the change of network coverage state of the anchor UE 104-2 from the anchor UE 104-2, and transmit the indication of the change of network coverage state of the anchor UE 104-2 to the network device 206-1.

In some embodiments, the UE may be the target UE 104-1. The target UE 104-1 may transmit, to the network device 206-1, assistance information for the determination 215. The assistance information may include mobility information of the target UE 104-1. Alternatively or additionally, the assistance information may include a Uu link quality of the target UE 104-1. Alternatively or additionally, the assistance information may include positioning request-related information, such as QoS requirement for positioning service of the target UE 104-1.

In some embodiments, after the target UE 104-1 enters network coverage for a pre-defined time window, the target UE 104-1 may report to the network device 206-1 that its network coverage state changes to be in-coverage. In this way, a ping-pang effect may be avoided.

In some embodiments, if the network coverage state of the target UE 104-1 changes to be in-coverage, the target UE 104-1 may transmit, to the network device 206-1, a request for a network device-dependent positioning operation. For example, the network device 206-1 may perform the determination 215 at least based on the request.

In some implementations, the first positioning operation may be network device-independent. If the network device 206-1 determines 215 a network device-independent positioning operation for the target UE 104-1, the network device 206-1 may transmit an indication of a network device-independent positioning operation to the target UE 104-1. The target UE 104-1 may continue the first positioning operation after receiving the indication.

In some embodiments, the network device 206-1 may transmit, to the target UE 104-1, a request for positioning session-related information associated with the first positioning operation and/or positioning request-related information. The target UE 104-1 may transmit the positioning session-related information and/or positioning request-related information to the network device 206-1. For example, the first positioning operation may be network device-independent and the network device 206-1 may determine a network device-dependent positioning operation when the network device 206-1 is aware that the network coverage state of the UE becomes in-coverage. The network device 206-1 may require positioning session-related information and/or positioning request-related information so as to guarantee the continuity and performance of the positioning service.

In some embodiments, the positioning request-related information may include a quality of service (QoS) requirement. The positioning session-related information may include information of the at least one anchor UE 104-2. Alternatively or additionally, the positioning session-related information may include a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation. Alternatively or additionally, the positioning session-related information may include a measurement configuration associated with the first positioning operation. Alternatively or additionally, the positioning session-related information may include measurement data in the first positioning operation. Alternatively or additionally, the positioning session-related information may include a session identity. Alternatively or additionally, the positioning session-related information may include a transaction identity. Alternatively or additionally, the positioning session-related information may include an indication of whether a reliable transmission was enabled in the first positioning operation.

In some embodiments, if the network device-dependent positioning operation is determined, the network device 206-1 may determine whether a server UE 104-3 is needed for the network device-dependent positioning operation. If the network device 206-1 determines that a server UE 104-3 is needed, the network device 206-1 may transmit, to the target UE 104-1, an indication of operations to be performed by the server UE 104-3, e.g., responsibilities of the server UE 104-3. The target UE 104-1 may forward the indication to the server UE 104-3. If the network device 206-1 determines that no server UE is needed, the network device 206-1 may transmit, to the target UE 104-1, an indication of releasing a server function by the server UE 104-3. The target UE 104-1 may forward the indication to the server UE 104-3.

In some embodiments, if the network coverage state of the target UE 104-1 changes to be out-of-coverage, the target UE 104-1 may transmit the indication of the change of network coverage state to the network device 206-1 via an in-coverage UE. The in-coverage UE may act as a relay UE between the target UE 104-1 and the network device 206-1. In some implementations, the in-coverage UE may be an anchor among the at least one anchor UE associated with the first positioning operation of the target UE 104-1. In some embodiments, the first positioning operation may be network device-dependent and the target UE 104-1 receives, from the network device 206-1 via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.

In some embodiments, the first positioning operation may be network device-dependent. If the network coverage state of the target UE 104-1 changes to be out-of-coverage, the target UE 104-1 may determine a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104- 1. If the target UE 104-1 determines a network device-independent positioning operation, the target UE 104-1 may transmit, to the network device 206-1 via an in-coverage UE, an indication of the network device-independent positioning operation. If the target UE 104-1 determines a network device-dependent positioning operation, the target UE 104-1 may transmit, to the network device 206-1 via an in-coverage UE, a request for the network device-dependent positioning operation and assistance information for the determination 215. The assistance information may include mobility information of the target UE 104-1. The in-coverage UE may act as a relay UE for communication between the target UE 104-1 and the network device 206-1. In some implementations, the in-coverage UE may be an anchor among the at least one anchor UE associated with the first positioning operation of the target UE 104-1.

In some cases, the target UE 104-1 may be initially out of network coverage and an in-coverage UE is a relay UE for communication between the target UE 104-1 and the network device 206-1. In some implementations, the in-coverage UE may be an anchor among the at least one anchor UE associated with the first positioning operation of the target UE 104-1. If the network coverage state of the target UE 104-1 changes to be in-coverage, the target UE 104-1 may transmit, to the in-coverage UE, an indication of releasing a relay function.

FIG. 2C shows an example signaling chart of a communication process 200C that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200C will be described with reference to FIGS. 1A-1E. The process 200C may involve the target UE 104-1 and an anchor UE 104-2 as illustrated in FIGS. 1B-1E. It is to be understood that the steps and the order of the steps in FIG. 2C are merely for illustration, and not for limitation. It is to be understood that process 200C may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2C, the anchor UE 104-2 determines 221 a change of network coverage state of the anchor UE 104-2. The anchor UE 104-2 transmits 222 an indication 223 of the change of network coverage state to the target UE 104-1. The target UE 104-1 receives 224 the indication 223 of the change of network coverage state of the anchor UE 104-2 from the anchor UE 104-2.

In some embodiments, when transmitting 222 the indication 223, the anchor UE 104-2 transmits, to the target UE 104-1, an indication that the network coverage state of the anchor UE 104-2 changes to be out-of-coverage if the anchor UE 104-2 moves out of network coverage. When transmitting 222 the indication 223, the anchor UE 104-2 transmits 222 an indication that the network coverage state of the anchor UE 104-2 changes to be in-coverage if the anchor UE 104-2 enters network coverage for a pre-defined time window. In this way, a ping-pang effect may be avoided.

In some cases, the first positioning operation may be network device-dependent. If the network coverage state of the UE changes to be out-of-network coverage, the target UE 104-1 may determine respective network coverage states of the at least one anchor UE associated with the first positioning operation of the target UE 104-1.

In some embodiments, if the at least one anchor UE associated with the first positioning operation of the target UE 104-1 and the target UE 104-1 are out of network coverage, e.g, if the target UE 104-1 determines that the coverage scenario changes to be an OOC scenario, the target UE 104-1 may determine a server UE 104-3 for a network device-independent positioning operation for the target UE 104-1 and perform the network device-independent positioning operation with the server UE 104-3. In some implementations, the target UE 104-1 may act as the server UE 104-3 for the network device-independent positioning operation. In other words, the target UE 104-1 may determine itself as the server UE.

The target UE 104-1 may transmit, to the at least one anchor UE, information of the selected server UE 104-3 for the network device-independent positioning operation. The anchor UE 104-2 may receive information of the server UE 104-3 from the target UE 104-1 and perform the network device-independent positioning operation with the server UE 104-3 and the target UE 104-1.

In some embodiments, the first positioning operation may be network device-dependent. If the at least one anchor UE and the target UE 104-1 are out of network coverage, the target UE 104-1 may determine an in-coverage UE as a relay UE for communication between the target UE 104-1 and the network device 206-1. If the in-coverage UE is not determined for a time period, the target UE 104-1 may abort the positioning session. If the in-coverage UE is determined, the target UE 104-1 may transmit, to the network device 206-1 via the in-coverage UE, positioning result or measurement data associated with the target UE 104-1.

In some embodiments, the first positioning operation may be network device-dependent and the target UE 104-1 may be in network coverage. If the network coverage state of the anchor UE 104-2 changes to be out-of-network coverage, the target UE 104-1 may reselect an anchor.

FIG. 2D shows an example signaling chart of a communication process 200D that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200D will be described with reference to FIGS. 1A-1E. The process 200D may involve the server UE 104-3 and the anchor UE 104-2 as illustrated in FIGS. 1B-1E. It is to be understood that the steps and the order of the steps in FIG. 2D are merely for illustration, and not for limitation. Similar reference numerals are used to denote the steps or components described in FIG. 2D having the same operations as the steps or components described in FIGS. 2A-2C, and detailed description thereof will be omitted. It is to be understood that process 200D may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2D, the anchor UE 104-2 determines 221 a change of network coverage state of the anchor UE 104-2. The anchor UE 104-2 transmits 232 an indication 223 of the change of network coverage state to the server UE 104-3. The server UE 104-3 receives 234 the indication 223 of the change of network coverage state of the anchor UE 104-2 from the anchor UE 104-2. The server UE 104-3 determines 205 a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104-1.

In some embodiments, when transmitting 232 the indication 223, the anchor UE 104-2 transmits an indication that the network coverage state of the anchor UE 104-2 changes to be in-coverage if the anchor UE 104-2 enters network coverage for a pre-defined time window. In this way, a ping-pang effect may be avoided.

In some embodiments, the anchor UE 104-2 may transmit assistance information for the determination 205 to the server UE 104-3. The assistance information may include mobility information of the anchor UE 104-2. Alternatively or additionally, the assistance information may include a Uu link quality of the anchor UE 104-2. Alternatively or additionally, the assistance information may include positioning request-related information, e.g., QoS requirements for positioning service of the target UE 104-1.

FIG. 2E shows an example signaling chart of a communication process 200E that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200E will be described with reference to FIGS. 1A-1E. The process 200E may involve the anchor UE 104-2 as illustrated in FIGS. 1B-1E and a network device 206-1. The network device 206-1 may be a network element of the core network 106 as illustrated in FIG. 1A. For example, the network device 206-1 may be implemented as a location server, such as the LMF 106-1 as illustrated in FIGS. 1B-1E. Other types of location servers are also possible. It is to be understood that the steps and the order of the steps in FIG. 2E are merely for illustration, and not for limitation. Similar reference numerals are used to denote the steps or components described in FIG. 2E having the same operations as the steps or components described in FIGS. 2A-2D, and detailed description thereof will be omitted. It is to be understood that process 200E may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2E, the anchor UE 104-2 determines 221 a change of network coverage state of the anchor UE 104-2. The anchor UE 104-2 transmits 242 an indication 223 of the change of network coverage state to the network device 206-1. The network device 206-1 receives 244 the indication 223 of the change of network coverage state of the anchor UE 104-2 from the anchor UE 104-2. The network device 206-1 determines 215 a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104-1.

In some embodiments, when transmitting 242 the indication 223, the anchor UE 104-2 transmits an indication that the network coverage state of the anchor UE 104-2 changes to be in-coverage if the anchor UE 104-2 enters network coverage for a pre-defined time window. In this way, a ping-pang effect may be avoided.

In some embodiments, the anchor UE 104-2 may transmit assistance information for the determination 215 to the network device 206-1. The assistance information may include mobility information of the anchor UE 104-2. Alternatively or additionally, the assistance information may include a Uu link quality of the anchor UE 104-2. Alternatively or additionally, the assistance information may include positioning request-related information, e.g., QoS requirements for positioning service of the target UE 104-1.

In some embodiments, if the network coverage state of the anchor UE 104-2 changes to be in-coverage, the anchor UE 104-2 may transmit, to the network device 206-1, a request for a network device-dependent positioning operation. For example, the network device 206-1 may perform the determination 215 at least based on the request.

In some implementations, the first positioning operation may be network device-independent. If the network device 206-1 determines 215 a network device-independent positioning operation for the target UE 104-1, the network device 206-1 may transmit an indication of a network device-independent positioning operation to the anchor UE 104-2. The anchor UE 104-2 may continue the first positioning operation after receiving the indication.

In some embodiments, the network device 206-1 may transmit, to the anchor UE 104-2, a request for positioning session-related information associated with the first positioning operation and/or positioning request-related information. The anchor UE 104-2 may transmit the positioning session-related information and/or positioning request-related information to the network device 206-1. For example, the first positioning operation may be network device-independent and the network device 206-1 may determine a network device-dependent positioning operation when the network device 206-1 is aware that the network coverage state of the anchor UE 104-2 becomes in-coverage. The network device 206-1 may require positioning session-related information and/or positioning request-related information so as to guarantee the continuity and performance of the positioning service.

In some embodiments, if the network device-dependent positioning operation is determined, the network device 206-1 may determine whether a server UE 104-3 is needed for the network device-dependent positioning operation. If the network device 206-1 determines that a server UE 104-3 is needed, the network device 206-1 may transmit, to the anchor UE 104-2, an indication of operations to be performed by the server UE 104-3. The anchor UE 104-2 may forward the indication to the server UE 104- 3. If the network device 206-1 determines that no server UE is needed, the network device 206-1 may transmit, to the anchor UE 104-2, an indication of releasing a server function by the server UE 104-3. The anchor UE 104-2 may forward the indication to the server UE 104-3.

FIG. 2F shows an example signaling chart of a communication process 200F that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200F will be described with reference to FIGS. 1A-1E. The process 200F may involve an in-coverage (IC) UE 204 and a network device 206-1. The network device 206-1 may be a network element of the core network 106 as illustrated in FIG. 1A. For example, the network device 206-1 may be implemented as a location server, such as the LMF 106-1 as illustrated in FIGS. 1B-1E. Other types of location servers are also possible. It is to be understood that the steps and the order of the steps in FIG. 2F are merely for illustration, and not for limitation. Similar reference numerals are used to denote the steps or components described in FIG. 2F having the same operations as the steps or components described in FIGS. 2A-2D, and detailed description thereof will be omitted. It is to be understood that process 200F may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

The IC UE 204 may be implemented as an involved UE (e.g., the target UE 104-1, an anchor UE 104-2, or the server UE 104-3) in an IC or PC scenario or a relay UE in an OOC scenario. For example, the IC UE 204 may be implemented as the target UE 104-1 if the target UE 104-1 is in the geographic coverage area 112. Alternatively or additionally, the IC UE 204 may be implemented as an anchor UE 104-2 or the server UE 104-3 in the geographic coverage area 112. In an OOC scenario, the IC UE 204 may be implemented as a relay UE which does not participate the positioning operation of the target UE 104-2.

As shown in FIG. 2F, the IC UE 204 obtains 251 a change of network coverage state of a UE. The UE is the target UE 104-1 or one of at least one anchor UE 104-2 associated with a first positioning operation for the target UE 104-1. The IC UE 204 transmits 252 an indication 253 of the change of network coverage state to the network device 206-1. The network device 206-1 receives 254 the indication 253 of the change of network coverage state of the UE from the IC UE 204. The network device 206-1 determines 215 a network device-dependent positioning operation or a network device-independent positioning operation for the target UE 104-1.

In some implementations, the anchor UE and the target UE may report changes in their own network coverage states to the network device 206-1, respectively. Alternatively, if the target UE 104-1 is in network coverage, changes in network coverage states of all the involved UEs may be reported to the network device 206-1 by the target UE 104-1. Alternatively or additionally, if the target UE 104-1 is out of network coverage, changes in network coverage states of all the involved UEs may be reported to the network device 206-1 by an in-coverage anchor UE or a relay UE.

In some embodiments, the IC UE 204 may transmit, to the network device 206-1, assistance information for the determination 215. The assistance information may include mobility information of the UE. Alternatively or additionally, the assistance information may include a Uu link quality of the UE. Alternatively or additionally, the assistance information may include positioning request-related information, such as QoS requirement for positioning service of the target UE 104-1.

In some embodiments, the IC UE 204 may transmit, to the network device 206-1, a request for a network device-dependent positioning operation.

In some implementations, the first positioning operation may be network device-independent. If the network device 206-1 determines 215 a network device-independent positioning operation for the target UE 104-1, the network device 206-1 may transmit an indication of a network device-independent positioning operation to the IC UE 204. The first positioning operation may be continued.

In some embodiments, the network device 206-1 may transmit, to the IC UE 204, a request for positioning session-related information associated with the first positioning operation and/or positioning request-related information. The IC UE 204 may transmit the positioning session-related information and/or positioning request-related information to the network device 206-1.

In some embodiments, if the network device 206-1 may determine whether a server UE 104-3 is needed for the network device-dependent positioning operation. If the network device 206-1 determines that a server UE 104-3 is needed, the network device 206-1 may transmit, to the IC UE 204, an indication of operations to be performed by the server UE 104-3. The IC UE 204 may forward the indication to the server UE 104-3. The server UE 104-3 may then perform these operations, i.e., take its responsibilities as a server UE. If the network device 206-1 determines that no server UE is needed, the network device 206-1 may transmit, to the IC UE 204, an indication of releasing a server function by the server UE 104-3. The IC UE 204 may forward the indication to the server UE 104-3. The server UE 104-3 may then release the server function.

In some embodiments, if the network device-dependent positioning operation is determined, the network device 206-1 may determine to perform the network device-dependent positioning operation with the at least one anchor UE associated with the first positioning operation of the target UE 104-1. Alternatively, if the network device-dependent positioning operation is determined, the network device 206-1 may determine to reselect anchor UEs for the network device-dependent positioning operation. Alternatively, if the network device-dependent positioning operation is determined, the network device 206-1 may determine to abort a sidelink positioning session and start a Uu positioning session or a hybrid Uu and PC5 positioning session in the case that the target UE 104-1 is in network coverage.

In some implementations, the first positioning operation may be network device-dependent. If the network device-dependent positioning operation is determined and that the target UE 104-1 is out of network coverage, the network device 206-1 may receive, from the IC UE 204, positioning result or measurement data associated with the target UE 104-1.

In some implementations, if the network device-dependent positioning operation is determined and that the target UE 104-1 is out of network coverage, the network device 206-1 may determine the IC UE 204 for communication between the target UE 104-1 and the network device 206-1. If an IC UE is not determined, the network device 206-1 may abort a positioning session.

In some implementations, if the network coverage state of the anchor UE 104-2 changes to be out-of-network coverage, the network device 206-1 may reselect an anchor UE. In some implementations, if the network device 206-1 does not receive responses from the anchor UE 104-2 for a period of time, the network device 206-1 may reselect an anchor UE. In some implementations, if the network device 206-1 does not receive responses from the anchor UE 104-2 for a period of time, the network device 206-1 may abort a positioning session.

In some implementations, the first positioning operation may be network device-dependent, and the network coverage state of the target UE 104-1 may change to be out-of-coverage. The network device 206-1 may receive, from the IC UE 204, an indication of the network device-independent positioning operation.

In some implementations, the first positioning operation may be network device-dependent, and the network coverage state of the target UE 104-1 may change to be out-of-coverage. The network device 206-1 may receive, from the IC UE 204, a request for the network device-dependent positioning operation and assistance information. The determination 215 may be performed based on the indication of the change of network coverage state of the UE and the assistance information. The assistance information may include mobility information of the target UE 104-1.

In some implementations, the first positioning operation may be network device-dependent, and the network coverage state of the target UE 104-1 may change to be out-of-coverage. The network device 206-1 may transmit, to the target UE 104-1 via the IC UE 204, an indication of a network device-independent positioning operation and positioning request-related information.

In some implementations, the first positioning operation may be network device-dependent, and the network coverage state of the target UE 104-1 may change to be out-of-coverage. If a network device-independent positioning operation is determined for the target UE 104-1, the network device 206-1 may determine that a server UE 104-3 is needed for the network device-independent positioning operation. The network device 206-1 may transmit, to the target UE 104-1 via the IC UE 204, an indication that a server UE 104-3 is needed. In some embodiments, the network device 206-1 may transmit, to the server UE for the network device-independent positioning operation, positioning request-related information and/or positioning session-related information associated with the first positioning operation. Alternatively or additionally, the network device 206-1 may transmit, to the server UE for the network device-independent positioning operation, an indication of operations to be performed by the server UE in the network device-independent positioning operation.

In some embodiments, the target UE 104-1 may be initially out of network coverage and the IC UE 204 is a relay UE for communication between the target UE 104-1 and the network device 206-1 prior to transmission of the indication 223. If the network coverage state of the target UE 104-1 changes to be in-coverage, the network device 206-1 may transmit, to the IC UE 204, an indication of releasing a relay function. Subsequent communication between the target UE 104-1 and the network device 206-1 may be performed directly.

FIG. 2G shows an example signaling chart of a communication process 200G that supports SL positioning with changes in coverage scenario in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the process 200G will be described with reference to FIGS. 1A-1E. The process 200Gmay involve the target UE 104-1 and the server UE 104-3 as illustrated in FIGS. 1B-1E. It is to be understood that the steps and the order of the steps in FIG. 2G are merely for illustration, and not for limitation. It is to be understood that process 200G may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

As shown in FIG. 2G, the target UE 104-1 transmits 261 positioning session-related information associated with the first positioning operation and/or positioning request-related information 262 to the server UE 104-3. The server UE 104-3 receives 263 the positioning session-related information and/or the positioning request-related information 262 and performs 264 a second positioning operation for the target UE 104-1 based on the positioning request-related information and/or the positioning session-related information.

In some implementations, the first positioning operation may be network device-dependent. If the network coverage state of the target UE 104-1 may change to be out-of-coverage or if the coverage scenario changes to be an OOC scenario, the network device 206-1 or the target UE 104-1 may determine a network device-independent positioning operation for the target UE 104-1. The target UE 104-1 may determine a server UE 104-3 for the network device-independent positioning operation. The target UE 104-1 may transmit at least one of the following to the server UE 104-3: positioning request-related information, positioning session-related information associated with the first positioning operation, or an indication of operations to be performed by the server UE 104-3 in the network device-independent positioning operation.

In some embodiments, the positioning request-related information and/or the positioning session-related information may be transmitted in a RequestAssistanceData message. In some embodiments, the server UE 104-3 may determine an updated configuration for the SL-PRS or an updated measurement configuration for the second positioning operation based on the positioning request-related information and/or the positioning session-related information. The second positioning operation may be performed based on the updated configuration or the updated measurement configuration. When performing the second positioning operation, the server UE 104-3 may receive measurement data associated with the target UE 104-1 from anchor UEs in a ProvideLocationInformation message. The server UE 104-3 may perform a location calculation for the target UE 104-1 based on the measurement data.

Hereinbefore, some embodiments of the SL positioning with changes in network coverage scenario are described in general terms. Hereinafter, some implementations of the SL positioning with changes in network coverage scenario will be further detailed in regard to various specific aspects.

The first specific aspect is how to design the procedure and signaling when SL positioning coverage scenario is changed from OOC to PC. In an initial OOC scenario, only LMF-independent SL positioning operation can be conducted. When the target UE or at least one of the anchor UEs enters into the network coverage, i.e., the coverage scenario changes to a PC scenario, both LMF-independent and LMF-dependent operation may be conducted. The information used to determine LMF-dependent (network-based) operation and LMF-independent (UE-only) operation needs to be specified. If a LMF-dependent operation is determined, some procedure and signaling are needed to guarantee the continuity of positioning service.

Reference is now made to FIG. 3A, which illustrates an example of a wireless communications system in a coverage scenario changing from an OOC scenario to a PC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system in FIG. 3A may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 3A having the same operations as the steps or components described in FIGS. 1B-2G, and detailed description thereof will be omitted. It should be understood that although the server UE 104-3 is illustrated as a different device from the target UE 104-1 and the anchor UEs 104-2, in some cases, the server UE 104-3 may be implemented by the target UE 104-1 itself or one of the anchor UEs 104-2.

As shown in FIG. 3A, the initial coverage scenario of the wireless communications system 100-4 is an OOC scenario where the target UE 104-1 and the anchor UEs 104-2 are out of coverage. Then, the target UE 104-1 moves into the geographic coverage area 112 and the changes in coverage scenario from an OOC scenario to a PC scenario. It should be understood that FIG. 3A is merely for illustration. For example, in some cases, an anchor UE 104-2, rather than the target UE 104-1, may move into the geographic coverage area 112, resulting in a change of the coverage scenario from an OOC scenario to a PC scenario.

As shown in FIG. 3A, in the initial OCC scenario, a LMF-independent SL positioning operation can be conducted. When at least one of the UEs (e.g., the target UE 104-1 as shown in FIG. 3A or an anchor UE 104-2) enters the network coverage for a pre-defined time window, it may inform the LMF 106-1 or the server UE 104-3. In addition, the UE in network coverage may also transmit, to the LMF 106-1 or the server UE 104-3, some necessary information such as UE mobility, the Uu link quality (e.g., Reference Signal Received Power, (RSRP) ) , and positioning service-related information, etc. The information may assist the LMF 106-1 or the server UE 104-3 to determine whether to involve the LMF 106-1 for SL positioning. It should be noted that the pre-defined time window is used to avoid ping-pang effect.

In some implementations, upon entering the network coverage for a pre-defined time window, the UE may inform the LMF 106-1 directly. In some examples, the UE may include a request for LMF-dependent operation in the message when informing the LMF 106-1 about the change in its coverage state. The LMF 106-1 may determine whether to initiate a LMF-dependent operation for the ongoing positioning service based on the received information. If the LMF 106-1 determines a LMF-independent operation, the LMF 106-1 may send an indication to the UE in network coverage. Then, the LMF-independent SL positioning maintains.

In some implementations, upon entering the network coverage for a pre-defined time window, the UE may inform the server UE 104-3 that it has a Uu connection now. The server UE 104-3 may determine whether to request a LMF-dependent operation based on the information provided by the UE in network coverage and based on the QoS requirements, etc.

If a LMF-dependent operation is determined by the LMF 106-1 itself or by the server UE 104-3, the LMF 106-1 may request the UE in the network coverage to provide the positioning request-related information (e.g., QoS requirement) and positioning session-related information (e.g., anchor UE information, the current SL-PRS configuration, the current measurement configuration, the current measurement result, session ID, transaction ID, whether a reliable transmission is enabled, etc. ) . The positioning session-related information may be used by the LMF 106-1 such that the LMF 106-1 is aware of the current state of positioning procedure.

In some implementations, upon receiving the positioning request-related information and the positioning session-related information from the UE in the network coverage, the LMF 106-1 may determine whether a server UE is needed, and sends the indication to the server UE via the UE in the network coverage. The indication may include the responsibility of a server UE if a server UE is needed, or the request to release a server functionality if a server UE is not needed any more. If the server UE 104-3 is in network coverage, the LMF 106-1 may inform the server UE 104-3 directly.

If a LMF-dependent operation is determined, the LMF 106-1 may determine to continue the SL positioning with the existing anchor UEs. Alternatively, if a LMF-dependent operation is determined, the LMF 106-1 may determine to reselect anchor UEs for SL positioning. Alternatively, if a LMF-dependent operation is determined, the LMF 106-1 may determine to abort the SL positioning session and start a Uu positioning session or hybrid Uu and PC5 positioning (only in the case that the target UE 104-1 enters the network coverage) . A LMF-dependent SL positioning or a Uu positioning or hybrid Uu and PC5 positioning may then be conducted.

The second specific aspect is how to design the procedure and signaling when SL positioning coverage scenario is changed from PC to OOC. In an initial PC scenario, either a LMF-independent or a LMF-dependent operation may be conducted. In the following description, only the case that a LMF-dependent operation is conducted in the initial PC scenario is discussed. It should be noted that principles of the disclosure also apply to the case where a LMF-independent operation is conducted in the initial PC scenario.

Additionally, either a mobile originating-location request (MO-LR) or a mobile terminated location request (MT-LR) may be initiated in the initial PC scenario. For the MO-LR case, the LMF may be not needed when the SL positioning coverage scenario is changed to OOC. By comparison, for the MT-LR case, at least the positioning result needs to be sent to the LMF. The procedures and signaling for the MT-LR and MO-LR cases need to be specified separately.

Reference is now made to FIG. 3B, which illustrates an example of a wireless communications system in a coverage scenario changing from a PC scenario to an OOC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system in FIG. 3B may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 3B having the same operations as the steps or components described in FIGS. 1B-2G, and detailed description thereof will be omitted. Although no server UE is illustrated in FIG. 3B, there may be a server UE in the wireless communications system in the PC scenario and/or in the OOC scenario.

As shown in FIG. 3B, in the initial PC scenario, the target UE 104-1 is in network coverage while the anchor UEs 104-2 are out of network coverage. In another case, an anchor UE may be in network coverage while the target UE 104-1 and the remaining anchor UEs 104-2 are out of network coverage. Then, the UE in network coverage may move out of coverage. In the subsequent scenario, all the target UE 104-1 and the anchor UEs 104-2 are out of network coverage.

Assuming a LMF-independent SL positioning operation is conducted in the initial PC scenario. When at least one of the in-coverage UEs (e.g., the target UE 104-1 as shown in FIG. 3B or an in-coverage anchor UE) moves out of the network coverage, the target UE 104-1 may determine an OOC scenario based on the coverage state of the involved UEs. For example, if an anchor UE 104-2 moves out of network coverage, it may inform the target UE 104-1. When the target UE 104-1 moves out of network coverage or it receives the indication of leaving network coverage from an anchor UE 104-2, the target UE 104-1 may check whether there is any in-coverage anchor UE currently. Alternatively, the target UE 104-1 may be aware of the coverage state of other anchor UEs and may directly determines it’s OOC scenario.

If the positioning request is initiated by an UE, i.e., in a (SL-) MO-LR case, upon determining the OOC scenario, the target UE 104-1 may discover and select a server UE or acts as a server UE by itself.

If a separate entity is determined as the new server UE, the target UE 104-1 may provide the selected server UE with the positioning request-related information (e.g., QoS requirement) , positioning session-related information (e.g., anchor information, the current SL-PRS configuration, measurement configuration, the current measurement result, session ID, transaction ID, whether reliable transmission is enabled, etc. ) and the responsibilities of the server UE (e.g., configuration, computation, assistance data distribution, anchor (re) selection, method determination, etc. ) .

In some implementations, the target UE 104-1 may include the positioning request-related information and the positioning session-related information in the RequestAssistanceData message. Upon receiving the RequestAssistanceData message, the selected server UE may provide updated configurations for the subsequent positioning operation. Upon receiving the measurement data included in the ProvideLocationInformation message, the server UE may perform position calculation of the target UE 104-1.

In some embodiments, the target UE 104-1 may indicate information of the selected server UE to the initial anchor UEs. The target UE 104-1, the selected server UE and the initial anchor UEs may perform the subsequent positioning operation. In some other embodiments, the server UE 104-3 may perform an anchor UE reselection.

If the positioning request is initiated by the network, i.e., in a (SL-) MT-LR case, the target UE 104-1 or the LMF 106-1 may determine an in-coverage relay UE for communication between the target UE 104-1 and the LMF 106-1.

For example, the target UE 104-1 may determine an IC SL relay UE to send at least the positioning result to the LMF 106-1. If no IC SL relay UE can be found for a period of time, the target UE 104-1 may abort the positioning session. If at least one IC SL relay UE can be found, the target UE 104-1 may send the positioning result or measurement data to the LMF 106-1 via the IC SL relay UE.

In another example, the LMF 106-1 may determine an IC SL relay UE that can connect to the target UE 104-1. The LMF 106-1 may communicate with the target UE 104-1 via the selected IC SL relay UE. If no such IC SL relay UE can be found, the LMF 106-1 may abort the positioning session.

Alternatively or additionally, the LMF 106-1 may abort the positioning session if no response is received for a period of time.

The third specific aspect is how to design the procedure and signaling when SL positioning coverage scenario is changed from IC to PC. In the following description, only the case that a LMF-dependent operation is conducted in the initial IC scenario is discussed. It should be noted that principles of the disclosure also apply to the case where a LMF-independent operation is conducted in the initial IC scenario. Either an anchor UE or the target UE may move out of coverage due to their mobility. If an anchor UE moves out of coverage, it’s likely that LMF-dependent operation is maintained. If the target UE moves out of coverage, the LMF may decide whether to keep the LMF-dependent operation and whether a server UE is needed. The associated procedures need to be elaborated.

Reference is now made to FIG. 3C, which illustrates an example of a wireless communications system in a coverage scenario changing from an IC scenario to a PC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system in FIG. 3C may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 3C having the same operations as the steps or components described in FIGS. 1B-2G, and detailed description thereof will be omitted. Although no server UE is illustrated in FIG. 3C, there may be a server UE in the wireless communications system in the IC scenario and/or in the PC scenario.

As shown in FIG. 3C, in the initial IC scenario, all the target UE 104-1 and the anchor UEs 104-2 are in network coverage. Assuming a LMF-dependent SL positioning operation is conducted in the initial IC scenario.

In some embodiments, if at least one anchor UE 104-2 moves out of coverage, the anchor UE 104-2 moving out of coverage may inform the target UE 104-1. Optionally, the target UE 104-1 may inform the LMF 106-1 about the coverage state change of the anchor UE 104-2. With the indication of coverage state change for anchor UE 104-2, the target UE 104-1 or the LMF 106-1 may decide whether to reselect an anchor UE.

In some implementations, if no responses are received from at least one anchor UE for a period of time, the LMF 106-1 may perform an anchor UE reselection or abort the positioning session. A LMF-dependent SL positioning may then be conducted if the positioning session is not aborted.

In some embodiments, when the target UE 104-1 moves out of coverage, the target UE 104-1 may determine whether to use a LMF-independent operation or to request LMF-dependent operation. If a LMF-independent operation is determined by the target UE 104-1, the target UE 104-1 may send an indication to the LMF 106-1 via one of the IC anchor UEs to inform the LMF 106-1 that a LMF-independent operation is determined.

If a LMF-dependent operation is determined by the target UE 104-1, the target UE 104-1 may send a request for a LMF-dependent operation to the LMF 106-1 via one of the IC anchor UEs, along with some necessary information such as UE mobility. Upon receiving the request for a LMF-dependent operation, the LMF 106-1 may determine a LMF-dependent operation or a LMF-independent operation based on the received information.

In some embodiments, when the target UE 104-1 moves out of coverage, the target UE 104-1 may inform its coverage state change to the LMF 106-1 via one of the IC anchor UEs. The message from the target UE 104-1 to the LMF 106-1 may also include necessary information that assist the LMF 106-1 to determine the operation, such as UE mobility information, etc. The LMF 106-1 may determine whether LMF-dependent or LMF-independent SL positioning operation is used based on the location service information (e.g., MO-LR or MT-LR) , UE mobility, positioning service-related information, etc. If a LMF-independent SL positioning is determined by the LMF 106-1, the LMF 106-1 may send an indication of a LMF-independent SL positioning to the target UE 104-1 via an IC anchor UE. The indication may include the positioning request-related information (e.g., QoS requirement) .

In some embodiments, if a LMF-independent operation is determined by the LMF 106-1 or the target UE 104-1, the target UE 104-1 may discover and select a server UE. In some implementations, the target UE 104-1 may send necessary information to the selected server UE, e.g., positioning request-related information, positioning session- related information, the responsibilities of the server UE, etc. In some other implementations, the target UE 104-1 may act as a server UE by itself. Then no information transmission needs to be performed.

In some embodiments, if a LMF-dependent operation is determined by the LMF 106-1 or the target UE 104-1, the LMF 106-1 may select a server UE with the assistance of the target UE 104-1 to assist the positioning operation. Alternatively, if a LMF-dependent operation is determined by the LMF 106-1 or the target UE 104-1, the LMF 106-1 may serve as a server and obtain measurement data via an IC anchor UE.

The fourth specific aspect is how to design the procedure and signaling when SL positioning coverage scenario is changed from PC to IC. In the following description, only the case that a LMF-dependent operation is conducted in the IC scenario is discussed. It should be noted that principles of the disclosure also apply to the case where a LMF-independent operation is conducted in the IC scenario.

There are two possible cases for the initial PC scenario. In a first case, the target UE 104-1 is in coverage and at least one anchor UE is out of coverage. In a second case, the target UE 104-1 is out of coverage and at least one anchor UE is in coverage. For the first case, it’s likely that a LMF-dependent operation is conducted in the initial PC scenario and in the IC scenario after the at least one OOC anchor UE moves into the network coverage. For the second case, either a LMF-dependent operation or a LMF-independent operation may be conducted in the initial PC scenario, and the associated procedures need to be specified separately.

Reference is now made to FIG. 3D, which illustrates an example of a wireless communications system in a coverage scenario changing from a PC scenario to an IC scenario in accordance with aspects of the present disclosure. It is noted that the wireless communications system in FIG. 3D may be considered as part of or a specific example of the wireless communications system 100 in FIG. 1A. Similar reference numerals are used to denote the steps or components described in FIG. 3D having the same operations as the steps or components described in FIGS. 1B-2G, and detailed description thereof will be omitted. Although no server UE is illustrated in FIG. 3D, there may be a server UE in the wireless communications system in the PC scenario and/or in the IC scenario.

As shown in FIG. 3D, in the initial PC scenario, the target UE 104-1 may be out of network coverage while the anchor UEs 104-2 are in network coverage. In another case, an anchor UE may be out of network coverage while the target UE 104-1 and the remaining anchor UEs 104-2 are in network coverage. Then, the UE out of network coverage may move into network coverage. In the subsequent scenario, all the target UE 104-1 and the anchor UEs 104-2 are in network coverage.

In some embodiments, assuming at least one anchor UE is out of coverage and the target UE 104-1 is in coverage in the initial PC scenario. When moving into the network coverage for a pre-defined time window, the anchor UE 104-2 may inform the target UE 104-1. The pre-defined time window may help to avoid a ping-pang effect. The target UE 104-1 may inform the LMF 106-1 about the coverage state change of the anchor UE moving into the network coverage. A LMF-dependent SL positioning may then be conducted.

Alternatively or additionally, when moving into the network coverage for a pre-defined time window, the anchor UE 104-2 may inform the LMF 106-1 about its coverage state change. A LMF-dependent SL positioning may then be conducted.

In some embodiments, assuming the target UE 104-1 is out of coverage, at least one anchor UE 104-2 is in coverage and a LMF-dependent SL positioning is conducted during the initial PC scenario. In some implementations, when moving in the network coverage for a pre-defined time window, the target UE 104-1 may inform the LMF 106-1. The target UE 104-1 and/or the LMF 106-1 may inform the relay (anchor) UE that the relay function is released.

In some embodiments, assuming the target UE 104-1 is out of coverage, at least one anchor UE 104-2 is in coverage and a LMF-independent SL positioning is conducted during the initial PC scenario. When the target UE 104-1 enters the network coverage for a pre-defined time window, the target UE 104-1 may inform the LMF 106-1 or the server UE about its coverage state change. In addition, the target UE 104-1 may transmit, to the LMF 106-1 or the server UE, necessary information, e.g., UE mobility, Uu link quality (e.g., RSRP) and positioning service-related information, etc.

In some implementations, upon entering the network coverage for a pre-defined time window, the target UE 104-1 may inform the LMF 106-1 directly. In some examples, the target UE 104-1 may include a request for LMF-dependent operation in the message when informing the LMF 106-1 about the change in its coverage state. The LMF 106-1 may determine whether to initiate a LMF-dependent operation for the ongoing positioning service based on the information received from the target UE 104-1. If the LMF 106-1 determines not to involve itself for the ongoing SL positioning, the LMF 106-1 may send an indication to the UE in network coverage. Then, the LMF-independent SL positioning maintains.

In some implementations, if there is a server UE in the initial PC scenario, upon entering the network coverage for a pre-defined time window, the target UE 104-1 may inform the server UE. The server UE may determine whether to request a LMF-dependent operation based on the information provided by the UE in network coverage and based on the QoS requirements, etc.

If a LMF-independent SL positioning is conducted during the initial PC scenario and a LMF-dependent operation is determined by the LMF 106-1 itself or by the server UE, the LMF 106-1 may request the target UE 104-1 entering the network coverage to provide the positioning request-related information and current positioning session-related information.

In some implementations, the LMF 106-1 may determine whether a server UE is needed. If no server is needed, the LMF 106-1 may inform the server UE (if there is a server UE in the initial PC scenario) that the server functionality is not needed anymore. If a server UE is needed, the LMF 106-1 may inform the server UE about the responsibilities of server UE.

In some implementations, the LMF 106-1 may determine to continue the SL positioning with existing anchor UEs. Alternatively, the LMF 106-1 may determine to reselect anchor UEs for SL positioning. Alternatively, the LMF 106-1 may determine to abort the SL positioning and start Uu positioning/hybrid Uu and PC5 positioning.

FIG. 4 illustrates an example of a device 400 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The device 400 may be an example of a first UE 104-1 as described herein. The device 400 may support wireless communication with one or more network entities 102, UEs 104, core networks 106 or any combination thereof. The device 400 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 402, a memory 404, a transceiver 406, and, optionally, an I/O controller 408. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 402, the memory 404, the transceiver 406, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 402, the memory 404, the transceiver 406, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 402 and the memory 404 coupled with the processor 402 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 402, instructions stored in the memory 404) .

For example, the processor 402 may support wireless communication at the device 400 in accordance with examples as disclosed herein. The processor 402 may be configured to operable to support a means for obtaining a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmitting, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.

The processor 402 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 402 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 402. The processor 402 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 404) to cause the device 400 to perform various functions of the present disclosure.

The memory 404 may include random access memory (RAM) and read-only memory (ROM) . The memory 404 may store computer-readable, computer-executable code including instructions that, when executed by the processor 402 cause the device 400 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 402 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 404 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 408 may manage input and output signals for the device 400. The I/O controller 408 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 408 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 408 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 408 may be implemented as part of a processor, such as the processor 406. In some implementations, a user may interact with the device 400 via the I/O controller 408 or via hardware components controlled by the I/O controller 408.

In some implementations, the device 400 may include a single antenna 410. However, in some other implementations, the device 400 may have more than one antenna 410 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 406 may communicate bi-directionally, via the one or more antennas 410, wired, or wireless links as described herein. For example, the transceiver 406 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 406 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 410 for transmission, and to demodulate packets received from the one or more antennas 410. The transceiver 406 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 410 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 410 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 5 illustrates an example of a device 500 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The device 500 may be an example of a second UE 104-2 as described herein. The device 500 may support wireless communication with one or more network entities 102, UEs 104, core networks 106 or any combination thereof. The device 500 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 502, a memory 504, a transceiver 506, and, optionally, an I/O controller 508. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 502, the memory 504, the transceiver 506, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 502, the memory 504, the transceiver 506, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 502, the memory 504, the transceiver 506, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 502 and the memory 504 coupled with the processor 502 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 502, instructions stored in the memory 504) .

For example, the processor 502 may support wireless communication at the device 500 in accordance with examples as disclosed herein. The processor 502 may be configured to operable to support a means for determining a change of network coverage state of the second UE; and transmitting an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.

The processor 502 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 502 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 502. The processor 502 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 504) to cause the device 500 to perform various functions of the present disclosure.

The memory 504 may include random access memory (RAM) and read-only memory (ROM) . The memory 504 may store computer-readable, computer-executable code including instructions that, when executed by the processor 502 cause the device 500 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 502 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 504 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 508 may manage input and output signals for the device 500. The I/O controller 508 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 508 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 508 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 508 may be implemented as part of a processor, such as the processor 506. In some implementations, a user may interact with the device 500 via the I/O controller 508 or via hardware components controlled by the I/O controller 508.

In some implementations, the device 500 may include a single antenna 510. However, in some other implementations, the device 500 may have more than one antenna 510 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 506 may communicate bi-directionally, via the one or more antennas 510, wired, or wireless links as described herein. For example, the transceiver 506 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 506 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 510 for transmission, and to demodulate packets received from the one or more antennas 510. The transceiver 506 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 510 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 510 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 6 illustrates an example of a device 600 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The device 600 may be an example of a third UE 104-3 as described herein. The device 600 may support wireless communication with one or more network entities 102, UEs 104, core networks 106 or any combination thereof. The device 600 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 602, a memory 604, a transceiver 606, and, optionally, an I/O controller 608. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 602, the memory 604, the transceiver 606, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 602, the memory 604, the transceiver 606, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 602, the memory 604, the transceiver 606, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 602 and the memory 604 coupled with the processor 602 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 602, instructions stored in the memory 604) .

For example, the processor 602 may support wireless communication at the device 600 in accordance with examples as disclosed herein. The processor 602 may be configured to operable to support a means for receiving one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information; and in the case that the indication of the change of network coverage state of the UE is received, determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or in the case that the positioning request-related information or the positioning session-related information is received, performing a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.

The processor 602 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 602 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 602. The processor 602 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 604) to cause the device 600 to perform various functions of the present disclosure.

The memory 604 may include random access memory (RAM) and read-only memory (ROM) . The memory 604 may store computer-readable, computer-executable code including instructions that, when executed by the processor 602 cause the device 600 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 602 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 604 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 608 may manage input and output signals for the device 600. The I/O controller 608 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 608 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 608 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 608 may be implemented as part of a processor, such as the processor 606. In some implementations, a user may interact with the device 600 via the I/O controller 608 or via hardware components controlled by the I/O controller 608.

In some implementations, the device 600 may include a single antenna 610. However, in some other implementations, the device 600 may have more than one antenna 610 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 606 may communicate bi-directionally, via the one or more antennas 610, wired, or wireless links as described herein. For example, the transceiver 606 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 606 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 610 for transmission, and to demodulate packets received from the one or more antennas 610. The transceiver 606 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 610 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 610 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 7 illustrates an example of a device 700 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The device 700 may be an example of a network device 206-1 or a LMF 106-1 as described herein. The device 700 may support wireless communication with one or more network entities 102, UEs 104, core networks 106 or any combination thereof. The device 700 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 702, a memory 704, a transceiver 706, and, optionally, an I/O controller 708. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 702, the memory 704, the transceiver 706, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 702, the memory 704, the transceiver 706, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 702, the memory 704, the transceiver 706, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 702 and the memory 704 coupled with the processor 702 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 702, instructions stored in the memory 704) .

For example, the processor 702 may support wireless communication at the device 700 in accordance with examples as disclosed herein. The processor 702 may be configured to operable to support a means for receiving, from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

The processor 702 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 702 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 702. The processor 702 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 704) to cause the device 700 to perform various functions of the present disclosure.

The memory 704 may include random access memory (RAM) and read-only memory (ROM) . The memory 704 may store computer-readable, computer-executable code including instructions that, when executed by the processor 702 cause the device 700 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 702 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 704 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 708 may manage input and output signals for the device 700. The I/O controller 708 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 708 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 708 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 708 may be implemented as part of a processor, such as the processor 706. In some implementations, a user may interact with the device 700 via the I/O controller 708 or via hardware components controlled by the I/O controller 708.

In some implementations, the device 700 may include a single antenna 710. However, in some other implementations, the device 700 may have more than one antenna 710 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 706 may communicate bi-directionally, via the one or more antennas 710, wired, or wireless links as described herein. For example, the transceiver 706 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 706 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 710 for transmission, and to demodulate packets received from the one or more antennas 710. The transceiver 706 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 710 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 710 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 8 illustrates an example of a processor 800 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The processor 800 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 800 may include a controller 802 configured to perform various operations in accordance with examples as described herein. The processor 800 may optionally include at least one memory 804, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 800 may optionally include one or more arithmetic-logic units (ALUs) 800. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 800 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 800) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 802 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 800 to cause the processor 800 to support various operations of a first UE 104-1 in accordance with examples as described herein. For example, the controller 802 may operate as a control unit of the processor 800, generating control signals that manage the operation of various components of the processor 800. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 802 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 804 and determine subsequent instruction (s) to be executed to cause the processor 800 to support various operations in accordance with examples as described herein. The controller 802 may be configured to track memory address of instructions associated with the memory 804. The controller 802 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 802 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 800 to cause the processor 800 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 802 may be configured to manage flow of data within the processor 800. The controller 802 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 800.

The memory 804 may include one or more caches (e.g., memory local to or included in the processor 800 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 804 may reside within or on a processor chipset (e.g., local to the processor 800) . In some other implementations, the memory 804 may reside external to the processor chipset (e.g., remote to the processor 800) .

The memory 804 may store computer-readable, computer-executable code including instructions that, when executed by the processor 800, cause the processor 800 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 802 and/or the processor 800 may be configured to execute computer-readable instructions stored in the memory 804 to cause the processor 800 to perform various functions. For example, the processor 800 and/or the controller 802 may be coupled with or to the memory 804, and the processor 800, the controller 802, and the memory 804 may be configured to perform various functions described herein. In some examples, the processor 800 may include multiple processors and the memory 804 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 800 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 800 may reside within or on a processor chipset (e.g., the processor 800) . In some other implementations, the one or more ALUs 800 may reside external to the processor chipset (e.g., the processor 800) . One or more ALUs 800 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 800 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 800 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 800 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 800 to handle conditional operations, comparisons, and bitwise operations.

The processor 800 may support wireless communication in accordance with examples as disclosed herein. The processor 800 may be configured to or operable to support a means for obtaining a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmitting, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.

FIG. 9 illustrates an example of a processor 900 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The processor 900 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 900 may include a controller 902 configured to perform various operations in accordance with examples as described herein. The processor 900 may optionally include at least one memory 904, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 900 may optionally include one or more arithmetic-logic units (ALUs) 900. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 900 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 900) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 902 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 900 to cause the processor 900 to support various operations of a second UE 104-2 in accordance with examples as described herein. For example, the controller 902 may operate as a control unit of the processor 900, generating control signals that manage the operation of various components of the processor 900. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 902 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 904 and determine subsequent instruction (s) to be executed to cause the processor 900 to support various operations in accordance with examples as described herein. The controller 902 may be configured to track memory address of instructions associated with the memory 904. The controller 902 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 902 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 900 to cause the processor 900 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 902 may be configured to manage flow of data within the processor 900. The controller 902 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 900.

The memory 904 may include one or more caches (e.g., memory local to or included in the processor 900 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 904 may reside within or on a processor chipset (e.g., local to the processor 900) . In some other implementations, the memory 904 may reside external to the processor chipset (e.g., remote to the processor 900) .

The memory 904 may store computer-readable, computer-executable code including instructions that, when executed by the processor 900, cause the processor 900 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 902 and/or the processor 900 may be configured to execute computer-readable instructions stored in the memory 904 to cause the processor 900 to perform various functions. For example, the processor 900 and/or the controller 902 may be coupled with or to the memory 904, and the processor 900, the controller 902, and the memory 904 may be configured to perform various functions described herein. In some examples, the processor 900 may include multiple processors and the memory 904 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 900 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 900 may reside within or on a processor chipset (e.g., the processor 900) . In some other implementations, the one or more ALUs 900 may reside external to the processor chipset (e.g., the processor 900) . One or more ALUs 900 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 900 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 900 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 900 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 900 to handle conditional operations, comparisons, and bitwise operations.

The processor 900 may support wireless communication in accordance with examples as disclosed herein. The processor 900 may be configured to or operable to support a means for determining a change of network coverage state of the second UE; and transmitting an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.

FIG. 10 illustrates an example of a processor 1000 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The processor 1000 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 1000 may include a controller 1002 configured to perform various operations in accordance with examples as described herein. The processor 1000 may optionally include at least one memory 1004, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 1000 may optionally include one or more arithmetic-logic units (ALUs) 1000. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 1000 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 1000) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 1002 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 1000 to cause the processor 1000 to support various operations of a third UE 104-3 in accordance with examples as described herein. For example, the controller 1002 may operate as a control unit of the processor 1000, generating control signals that manage the operation of various components of the processor 1000. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 1002 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 1004 and determine subsequent instruction (s) to be executed to cause the processor 1000 to support various operations in accordance with examples as described herein. The controller 1002 may be configured to track memory address of instructions associated with the memory 1004. The controller 1002 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 1002 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 1000 to cause the processor 1000 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 1002 may be configured to manage flow of data within the processor 1000. The controller 1002 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 1000.

The memory 1004 may include one or more caches (e.g., memory local to or included in the processor 1000 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 1004 may reside within or on a processor chipset (e.g., local to the processor 1000) . In some other implementations, the memory 1004 may reside external to the processor chipset (e.g., remote to the processor 1000) .

The memory 1004 may store computer-readable, computer-executable code including instructions that, when executed by the processor 1000, cause the processor 1000 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 1002 and/or the processor 1000 may be configured to execute computer-readable instructions stored in the memory 1004 to cause the processor 1000 to perform various functions. For example, the processor 1000 and/or the controller 1002 may be coupled with or to the memory 1004, and the processor 1000, the controller 1002, and the memory 1004 may be configured to perform various functions described herein. In some examples, the processor 1000 may include multiple processors and the memory 1004 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 1000 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 1000 may reside within or on a processor chipset (e.g., the processor 1000) . In some other implementations, the one or more ALUs 1000 may reside external to the processor chipset (e.g., the processor 1000) . One or more ALUs 1000 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 1000 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 1000 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 1000 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 1000 to handle conditional operations, comparisons, and bitwise operations.

The processor 1000 may support wireless communication in accordance with examples as disclosed herein. The processor 1000 may be configured to or operable to support a means for receiving one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information; and in the case that the indication of the change of network coverage state of the UE is received, determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or in the case that the positioning request-related information or the positioning session-related information is received, performing a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.

FIG. 11 illustrates an example of a processor 1100 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The processor 1100 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 1100 may include a controller 1102 configured to perform various operations in accordance with examples as described herein. The processor 1100 may optionally include at least one memory 1104, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 1100 may optionally include one or more arithmetic-logic units (ALUs) 1100. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 1100 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 1100) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 1102 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 1100 to cause the processor 1100 to support various operations of a network device 206-1 or a LMF 106-1 in accordance with examples as described herein. For example, the controller 1102 may operate as a control unit of the processor 1100, generating control signals that manage the operation of various components of the processor 1100. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 1102 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 1104 and determine subsequent instruction (s) to be executed to cause the processor 1100 to support various operations in accordance with examples as described herein. The controller 1102 may be configured to track memory address of instructions associated with the memory 1104. The controller 1102 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 1102 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 1100 to cause the processor 1100 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 1102 may be configured to manage flow of data within the processor 1100. The controller 1102 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 1100.

The memory 1104 may include one or more caches (e.g., memory local to or included in the processor 1100 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 1104 may reside within or on a processor chipset (e.g., local to the processor 1100) . In some other implementations, the memory 1104 may reside external to the processor chipset (e.g., remote to the processor 1100) .

The memory 1104 may store computer-readable, computer-executable code including instructions that, when executed by the processor 1100, cause the processor 1100 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 1102 and/or the processor 1100 may be configured to execute computer-readable instructions stored in the memory 1104 to cause the processor 1100 to perform various functions. For example, the processor 1100 and/or the controller 1102 may be coupled with or to the memory 1104, and the processor 1100, the controller 1102, and the memory 1104 may be configured to perform various functions described herein. In some examples, the processor 1100 may include multiple processors and the memory 1104 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 1100 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 1100 may reside within or on a processor chipset (e.g., the processor 1100) . In some other implementations, the one or more ALUs 1100 may reside external to the processor chipset (e.g., the processor 1100) . One or more ALUs 1100 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 1100 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 1100 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 1100 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 1100 to handle conditional operations, comparisons, and bitwise operations.

The processor 1100 may support wireless communication in accordance with examples as disclosed herein. The processor 1100 may be configured to or operable to support a means for receiving, from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

FIG. 12 illustrates a flowchart of a method 1200 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1200 may be implemented by a device or its components as described herein. For example, the operations of the method 1200 may be performed by a first UE 104-1 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1205, the method may include obtaining a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE. The operations of 1205 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1205 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1210, the method may include transmitting, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE. The operations of 1210 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1210 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 13 illustrates a flowchart of a method 1300 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1300 may be implemented by a device or its components as described herein. For example, the operations of the method 1300 may be performed by a first UE 104-1 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware. The method 1300 may be deemed as a continuation of the method 1200.

At 1305, the method may include receiving, from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information, wherein the first positioning operation is network device-independent, and the first UE is in network coverage. The operations of 1305 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1305 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1310, the method may include transmitting, to the network device, the positioning request-related information or the positioning session-related information. The operations of 1310 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1310 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 14 illustrates a flowchart of a method 1400 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1400 may be implemented by a device or its components as described herein. For example, the operations of the method 1400 may be performed by a second UE 104-2 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1405, the method may include determining a change of network coverage state of the second UE. The operations of 1405 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1405 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1410, the method may include transmitting an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device. The operations of 1410 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1410 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 15 illustrates a flowchart of a method 1500 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1500 may be implemented by a device or its components as described herein. For example, the operations of the method 1500 may be performed by a second UE 104-2 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware. The method 1500 may be deemed as a continuation of the method 1400.

At 1505, the method may include receiving, from the first UE, an indication that the network coverage state of the first UE changes to be out-of-coverage, wherein the first positioning operation is network device-dependent, the second UE is in network coverage. The operations of 1505 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1505 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1510, the method may include transmitting, to the network device, the indication that the network coverage state of the first UE changes to be out-of-coverage. The operations of 1510 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1510 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 16 illustrates a flowchart of a method 1600 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1600 may be implemented by a device or its components as described herein. For example, the operations of the method 1600 may be performed by a third UE 104-3 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1605, the method may include receiving an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE. The operations of 1605 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1605 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1610, the method may include determining determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE. The operations of 1610 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1610 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 17 illustrates a flowchart of a method 1700 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1700 may be implemented by a device or its components as described herein. For example, the operations of the method 1700 may be performed by a third UE 104-3 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware. The method 1700 may be deemed as a continuation of the method 1600.

At 1705, the method may include receiving positioning session-related information associated with the first positioning operation or positioning request-related information. The operations of 1705 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1705 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1710, the method may include performing a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information. The operations of 1710 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1710 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 18 illustrates a flowchart of a method 1800 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1800 may be implemented by a device or its components as described herein. For example, the operations of the method 1800 may be performed by a third UE 104-3 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware. The method 1800 may be deemed as a specific implementation of the step 1710 in of the method 1700.

At 1805, the method may include determining an updated configuration for the SL-PRS or an updated measurement configuration. The operations of 1805 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1805 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1810, the method may include performing the second positioning operation based on the updated configuration or the updated measurement configuration. The operations of 1810 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1810 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 19 illustrates a flowchart of a method 1900 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 1900 may be implemented by a device or its components as described herein. For example, the operations of the method 1900 may be performed by a network device 206-1 or a LMF 106-1 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 1905, the method may include receiving, from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE. The operations of 1905 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1905 may be performed by a device as described with reference to FIGS. 1A-1E.

At 1910, the method may include determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE. The operations of 1910 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 1910 may be performed by a device as described with reference to FIGS. 1A-1E.

FIG. 20 illustrates a flowchart of a method 2000 that supports SL positioning with changes in coverage scenario in accordance with aspects of the present disclosure. The operations of the method 2000 may be implemented by a device or its components as described herein. For example, the operations of the method 2000 may be performed by a network device 206-1 or a LMF 106-1 as described herein. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware. The method 2000 may be deemed as a continuation of the method 1900.

At 2005, the method may include transmitting, to the in-coverage UE, a request for positioning session-related information associated with the first positioning operation or positioning request-related information. The operations of 2005 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 2005 may be performed by a device as described with reference to FIGS. 1A-1E.

At 2010, the method may include receiving, from the in-coverage UE, the positioning request-related information or the positioning session-related information. The operations of 2010 may be performed in accordance with examples as described herein. In some implementations, aspects of the operations of 2010 may be performed by a device as described with reference to FIGS. 1A-1E.

It should be noted that the methods described herein describes possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

As used herein, including in the claims, an article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on”shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

In summary, embodiments of the present disclosure may provide the following solutions.

Clause 1. A first user equipment (UE) comprising: a processor; and a transceiver coupled to the processor, wherein the processor is configured to: obtain a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmit, via the transceiver to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.

Clause 2. The first UE of clause 1, wherein the UE is the first UE, and the processor is further configured to: transmit, via the transceiver to the network device or the third UE, assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

Clause 3. The first UE of clause 2, wherein the assistance information comprises one of the following: mobility information of the first UE; a Uu link quality of the first UE; or positioning request-related information.

Clause 4. The first UE of clause 1, wherein transmitting the indication of the change of network coverage state of the UE comprises: in the case that the first UE enters network coverage for a pre-defined time window, transmitting, via the transceiver to the third UE or the network device, an indication that the network coverage state of the first UE changes to be in-coverage.

Clause 5. The first UE of clause 1, wherein the processor is further configured to:in the case that the network coverage state of the first UE changes to be in-coverage, transmit, via the transceiver to the network device, a request for a network device-dependent positioning operation.

Clause 6. The first UE of clause 1, wherein the first positioning operation is network device-independent, and the processor is further configured to: in the case that the first UE is in network coverage, receive, via the transceiver from the network device, an indication of a network device-independent positioning operation; and continue the first positioning operation.

Clause 7. The first UE of clause 1, wherein the first positioning operation is network device-independent, and the processor is further configured to: in the case that the first UE is in network coverage, receive, via the transceiver from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and transmit, via the transceiver to the network device, the positioning request-related information or the positioning session-related information.

Clause 8. The first UE of clause 1, wherein the processor is further configured to: in the case that the first UE is in network coverage, receive, via the transceiver from the network device, an indication of operations to be performed by the third UE or an indication of releasing a server function; and transmit, via the transceiver to the third UE, the indication of operations to be performed by the third UE or the indication of releasing a server function.

Clause 9. The first UE of clause 1, wherein the first positioning operation is network device-dependent, and the processor is further configured to: in the case that the network coverage state of the UE changes to be out-of-network coverage, determine respective network coverage states of the at least one second UE.

Clause 10. The first UE of clause 1, wherein the first positioning operation is network device-dependent, and the processor is further configured to: in the case that the at least one second UE and the first UE are out of network coverage, determine a third UE for a network device-independent positioning operation for the first UE; and perform the network device-independent positioning operation with the third UE.

Clause 11. The first UE of clause 10, wherein the first UE acts as the third UE for the network device-independent positioning operation.

Clause 12. The first UE of clause 10, wherein the processor is further configured to: transmit, via the transceiver to the at least one second UE, information of the third UE for the network device-independent positioning operation.

Clause 13. The first UE of clause 1, wherein the first positioning operation is network device-dependent, and the processor is further configured to: in the case that the at least one second UE and the first UE are out of network coverage, determine an in-coverage UE as a relay UE for communication between the first UE and the network device; and transmit, via the transceiver to the network device via the in-coverage UE, positioning result or measurement data associated with the first UE.

Clause 14. The first UE of clause 13, wherein the processor is further configured to: in the case that the in-coverage UE is not determined for a time period, abort a positioning session.

Clause 15. The first UE of clause 1, wherein the first positioning operation is network device-dependent, the first UE is in network coverage, the UE is the second UE, and the processor is further configured to: in the case that the network coverage state of the second UE changes to be out-of-network coverage, reselect a second UE.

Clause 16. The first UE of clause 1, wherein the first positioning operation is network device-dependent, the UE is the first UE, and the processor is further configured to: in the case that the network coverage state of the first UE changes to be out-of-coverage, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; and in the case that the network device-independent positioning operation is determined, transmit, via the transceiver to the network device via an in-coverage UE, an indication of the network device-independent positioning operation; or in the case that the network device-dependent positioning operation is determined, transmit, via the transceiver to the network device via an in-coverage UE, a request for the network device-dependent positioning operation and assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE by the network device.

Clause 17. The first UE of clause 16, wherein the assistance information comprises mobility information of the first UE.

Clause 18. The first UE of clause 1, wherein the network coverage state of the first UE changes to be out-of-coverage, and the indication of the change of network coverage state is transmitted to the network device via an in-coverage UE.

Clause 19. The first UE of clause 18, wherein the first positioning operation is network device-dependent, and the processor is further configured to: receive, via the transceiver from the network device via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.

Clause 20. The first UE of clause 1, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to: in the case that a network device-independent positioning operation is determined for the first UE, determine a third UE for the network device-independent positioning operation.

Clause 21. The first UE of clause 10 or 20, wherein the processor is further configured to: transmit, via the transceiver to the third UE for the network device-independent positioning operation, one of the following: positioning request-related information, positioning session-related information associated with the first positioning operation, or an indication of operations to be performed by the third UE in the network device-independent positioning operation.

Clause 22. The first UE of clause 7 or 21, wherein the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of the at least one second UE; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

Clause 23. The first UE of clause 21, wherein the positioning request-related information or the positioning session-related information is transmitted in a RequestAssistanceData message.

Clause 24. The first UE of clause 1, wherein the first UE is out of network coverage and an in-coverage UE is a relay UE for communication between the first UE and the network device prior to obtaining the change of network coverage state of the first UE, and the processor is further configured to: in the case that the network coverage state of the first UE changes to be in-coverage, transmit, via the transceiver to the in-coverage UE, an indication of releasing a relay function.

Clause 25. The first UE of any of clauses 16, 18 and 24, wherein the in-coverage UE is a second UE among the at least one second UE.

Clause 26. The first UE of clause 1, wherein determining the change of network coverage state of the second UE comprises: receiving, via the transceiver from the second UE, an indication of the change of network coverage state of the second UE.

Clause 27. A second user equipment (UE) comprising: a processor; and a transceiver coupled to the processor, wherein the processor is configured to: determine a change of network coverage state of the second UE; and transmit, via the transceiver, an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.

Clause 28. The second UE of clause 27, wherein transmitting the indication of the change of network coverage state of the second UE comprises one of the following: transmitting, via the transceiver, an indication that the network coverage state of the second UE changes to be in-coverage in the case that the second UE enters network coverage for a pre-defined time window; or transmitting, via the transceiver to the first UE, an indication that the network coverage state of the second UE changes to be out-of-coverage in the case that the second UE moves out of network coverage.

Clause 29. The second UE of clause 27, wherein the processor is further configured to: transmit, via the transceiver to the network device or the third UE, assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

Clause 30. The second UE of clause 29, wherein the assistance information comprises one of the following: mobility information of the second UE; a Uu link quality of the second UE; or positioning request-related information.

Clause 31. The second UE of clause 27, wherein the processor is further configured to: in the case that the network coverage state of the second UE changes to be in-coverage, transmit, via the transceiver to the network device, a request for a network device-dependent positioning operation.

Clause 32. The second UE of clause 27, wherein the first positioning operation is network device-independent, and the processor is further configured to: in the case that the second UE is in network coverage, receive, via the transceiver from the network device, an indication of a network device-independent positioning operation; and continue the first positioning operation.

Clause 33. The second UE of clause 27, wherein the first positioning operation is network device-independent, and the processor is further configured to: in the case that the second UE is in network coverage, receive, via the transceiver from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and transmit, via the transceiver to the network device, the positioning request-related information or the positioning session-related information.

Clause 34. The second UE of clause 27, wherein the processor is further configured to: in the case that the second UE is in network coverage, receive, via the transceiver from the network device, an indication of operations to be performed by the third UE or an indication of releasing a server function; and transmit, via the transceiver to the third UE, the indication of operations to be performed by the third UE or the indication of releasing a server function.

Clause 35. The second UE of clause 27, wherein the first positioning operation is network device-dependent, and the processor is further configured to: receive, via the transceiver from the first UE, information of a third UE for a network device-independent positioning operation for the first UE; and perform the network device-independent positioning operation with the third UE and the first UE.

Clause 36. The second UE of clause 27, wherein the first positioning operation is network device-dependent, the second UE is in network coverage, and the processor is further configured to: receive, via the transceiver from the first UE, an indication of a network device-independent positioning operation; and transmit, via the transceiver to the network device, the indication of the network device-independent positioning operation.

Clause 37. The second UE of clause 27, wherein the first positioning operation is network device-dependent, the second UE is in network coverage, and the processor is further configured to: receive, via the transceiver from the first UE, a request for a network device-dependent positioning operation and assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE by the network device; and transmit, via the transceiver to the network device, the request for the network device-dependent positioning operation and the assistance information.

Clause 38. The second UE of clause 37, wherein the assistance information comprises mobility information of the first UE.

Clause 39. The second UE of clause 27, wherein the first positioning operation is network device-dependent, the second UE is in network coverage, and the processor is further configured to: receive, via the transceiver from the first UE, an indication that the network coverage state of the first UE changes to be out-of-coverage; and transmit, via the transceiver to the network device, the indication that the network coverage state of the first UE changes to be out-of-coverage.

Clause 40. The second UE of clause 27, wherein the first positioning operation is network device-dependent, the second UE is in network coverage, and the processor is further configured to: receive, via the transceiver from the network device, an indication of a network device-independent positioning operation and positioning request-related information; and transmit, via the transceiver to the first UE, the indication of the network device-independent positioning operation and positioning request-related information.

Clause 41. The second UE of clause 33 or 40, wherein the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of at least one second UE associated with the first positioning operation; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

Clause 42. The second UE of clause 27, wherein the second UE is in network coverage as a relay UE for communication between the first UE and the network device, and the processor is further configured to: receive, via the transceiver from the first UE or the network device, an indication of releasing a relay function.

Clause 43. A third user equipment (UE) comprising: a processor; and a transceiver coupled to the processor, wherein the processor is configured to: receive, via the transceiver, one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information; and in the case that the indication of the change of network coverage state of the UE is received, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or in the case that the positioning request-related information or the positioning session-related information is received, perform a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.

Clause 44. The third UE of clause 43, wherein the processor is further configured to: receive, via the transceiver from the UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Clause 45. The third UE of clause 43, wherein the processor is further configured to: receive, via the transceiver from the first UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Clause 46. The third UE of clause 44 or 45, wherein the assistance information comprises one of the following: mobility information of the UE; a Uu link quality of the UE; or positioning request-related information.

Clause 47. The third UE of clause 43, wherein the processor is further configured to: receive, via the transceiver from the network device or an in-coverage UE, an indication of operations to be performed by the third UE or an indication of releasing a server function; and perform the operations in the case that the indication of the operations is received; or release the server function in the case that the indication of releasing the server function is received.

Clause 48. The third UE of clause 43, wherein the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of the at least one second UE; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

Clause 49. The third UE of clause 43, wherein the positioning request-related information or the positioning session-related information is received in a RequestAssistanceData message, and the processor is further configured to: determine an updated configuration for the SL-PRS or an updated measurement configuration, and wherein the second positioning operation is performed based on the updated configuration or the updated measurement configuration.

Clause 50. The third UE of clause 43, wherein performing the second positioning operation comprises: receiving, via the transceiver, measurement data associated with the first UE in a ProvideLocationInformation message; and performing a location calculation for the first UE based on the measurement data.

Clause 51. A network device comprising: a processor; and a transceiver coupled to the processor, wherein the processor is configured to: receive, via the transceiver from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

Clause 52. The network device of clause 51, wherein the processor is further configured to: receive, via the transceiver from the in-coverage UE, assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Clause 53. The network device of clause 52, wherein the assistance information comprises one of the following: mobility information of the UE; a Uu link quality of the UE; or positioning request-related information.

Clause 54. The network device of clause 51, wherein the processor is further configured to: receive, via the transceiver from the in-coverage UE, a request for a network device-dependent positioning operation.

Clause 55. The network device of clause 51, wherein the first positioning operation is network device-independent, and the processor is further configured to: in the case that the network device-independent positioning operation is determined, transmit, via the transceiver to the in-coverage UE, an indication of the network device-independent positioning operation.

Clause 56. The network device of clause 51, wherein the processor is further configured to: transmit, via the transceiver to the in-coverage UE, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and receive, via the transceiver from the in-coverage UE, the positioning request-related information or the positioning session-related information.

Clause 57. The network device of clause 51, wherein the processor is further configured to: in the case that the network device-dependent positioning operation is determined, determine whether a third UE is needed for the network device-dependent positioning operation; and in the case that a third UE is needed, transmit, via the transceiver to the third UE via the in-coverage UE, an indication of operations to be performed by the third UE; or in the case that no third UE is needed, transmit, via the transceiver to the third UE via the in-coverage UE, an indication of releasing a server function by the third UE.

Clause 58. The network device of clause 51, wherein the processor is further configured to: in the case that the network device-dependent positioning operation is determined, determine one of the following: performing the network device-dependent positioning operation with the at least one second UE; reselecting second UEs for the network device-dependent positioning operation; or aborting a sidelink positioning session and starting a Uu positioning session or a hybrid Uu and PC5 positioning session in the case that the first UE is in network coverage.

Clause 59. The network device of clause 51, wherein the first positioning operation is network device-dependent, and the processor is further configured to: in the case that the network device-dependent positioning operation is determined and that the first UE is out of network coverage, receive, via the transceiver from the in-coverage UE, positioning result or measurement data associated with the first UE.

Clause 60. The network device of clause 59, wherein the processor is further configured to: in the case that the network device-dependent positioning operation is determined and that the first UE is out of network coverage, determine the in-coverage UE for communication between the first UE and the network device; and in the case that an in-coverage UE is not determined, abort a positioning session.

Clause 61. The network device of clause 51, wherein the processor is further configured to: in the case that the network coverage state of the second UE changes to be out-of-network coverage, reselect a second UE.

Clause 62. The network device of clause 51, wherein the processor is further configured to: in the case that the network device does not receive responses from the second UE for a period of time, perform one of the following: reselecting a second UE; or aborting a positioning session.

Clause 63. The network device of clause 51, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to: receive, via the transceiver from the in-coverage UE, an indication of the network device-independent positioning operation.

Clause 64. The network device of clause 51, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to: receive, via the transceiver from the in-coverage UE, a request for the network device-dependent positioning operation and assistance information, and wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.

Clause 65. The network device of clause 64, wherein the assistance information comprises mobility information of the first UE.

Clause 66. The network device of clause 51, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to: transmit, via the transceiver to the first UE via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.

Clause 67. The network device of clause 51, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to: in the case that a network device-independent positioning operation is determined for the first UE, determine that a third UE is needed for the network device-independent positioning operation; and transmit, via the transceiver to the first UE via the in-coverage UE, an indication that a third UE is needed.

Clause 68. The network device of clause 67, wherein the processor is further configured to: transmit, via the transceiver to the third UE for the network device-independent positioning operation, one of the following: positioning request-related information, positioning session-related information associated with the first positioning operation, or an indication of operations to be performed by the third UE in the network device-independent positioning operation.

Clause 69. The network device of clause 56 or 68, wherein the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following: information of the at least one second UE; a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation; a measurement configuration associated with the first positioning operation; measurement data in the first positioning operation; a session identity; a transaction identity; or an indication of whether a reliable transmission was enabled in the first positioning operation.

Clause 70 The network device of clause 51, wherein the first UE is out of network coverage and the in-coverage UE is a relay UE for communication between the first UE and the network device prior to receiving the indication, and the processor is further configured to: in the case that the network coverage state of the first UE changes to be in-coverage, transmit, via the transceiver to the in-coverage UE, an indication of releasing a relay function.

Clause 71. The network device of clause 51, wherein the in-coverage UE is a second UE among the at least one second UE or the first UE.

Clause 72. A method performed by a first user equipment (UE) , the method comprising: obtaining a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmitting, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.

Clause 73. A method performed by a second user equipment (UE) , the method comprising: determining a change of network coverage state of the second UE; and transmitting an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.

Clause 74. A method performed by a third user equipment (UE) , the method comprising: receiving one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information; and in the case that the indication of the change of network coverage state of the UE is received, determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or in the case that the positioning request-related information or the positioning session-related information is received, performing a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.

Clause 75. A method performed by a network device, the method comprising: receiving, from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determining a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

Clause 76. A processor for wireless communication, comprising: at least one memory; and a controller coupled with the at least one memory and configured to cause the controller to: obtain a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and transmit, to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.

Clause 77. A processor for wireless communication, comprising: at least one memory; and a controller coupled with the at least one memory and configured to cause the controller to: determine a change of network coverage state of a second UE; and transmit, via the transceiver, an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.

Clause 78. A processor for wireless communication, comprising: at least one memory; and a controller coupled with the at least one memory and configured to cause the controller to: receive, via the transceiver, one of the following: an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or positioning session-related information associated with the first positioning operation or positioning request-related information; and in the case that the indication of the change of network coverage state of the UE is received, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or in the case that the positioning request-related information or the positioning session-related information is received, perform a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.

Clause 79. A processor for wireless communication, comprising: at least one memory; and a controller coupled with the at least one memory and configured to cause the controller to: receive, via the transceiver from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.

Clause 80. A non-transitory computer readable medium having program instructions stored thereon that, when executed by an apparatus, cause the apparatus at least to perform the method of any of clauses 72-75.

Claims

A first user equipment (UE) comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

obtain a change of network coverage state of a UE, wherein the UE is the first UE or one of at least one second UE associated with a first positioning operation for the first UE; and

transmit, via the transceiver to a third UE associated with the first positioning operation or a network device, an indication of the change of network coverage state of the UE.
The first UE of claim 1, wherein the UE is the first UE, and the processor is further configured to:

transmit, via the transceiver to the network device or the third UE, assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE,

wherein the assistance information comprises one of the following:

mobility information of the first UE;

a Uu link quality of the first UE; or

positioning request-related information.
The first UE of claim 1, wherein transmitting the indication of the change of network coverage state of the UE comprises:

in the case that the first UE enters network coverage for a pre-defined time window, transmitting, via the transceiver to the third UE or the network device, an indication that the network coverage state of the first UE changes to be in-coverage.
The first UE of claim 1, wherein the first positioning operation is network device-independent, and the processor is further configured to:

in the case that the first UE is in network coverage, receive, via the transceiver from the network device, an indication of a network device-independent positioning operation; and

continue the first positioning operation.
The first UE of claim 1, wherein the first positioning operation is network device-independent, and the processor is further configured to:

in the case that the first UE is in network coverage, receive, via the transceiver from the network device, a request for positioning session-related information associated with the first positioning operation or positioning request-related information; and

transmit, via the transceiver to the network device, the positioning request-related information or the positioning session-related information,

wherein the positioning request-related information comprises a quality of service (QoS) requirement, and the positioning session-related information comprises one of the following:

information of the at least one second UE;

a configuration for a sidelink positioning reference signal (SL-PRS) for the first positioning operation;

a measurement configuration associated with the first positioning operation;

measurement data in the first positioning operation;

a session identity;

a transaction identity; or

an indication of whether a reliable transmission was enabled in the first positioning operation.
The first UE of claim 1, wherein the first positioning operation is network device-dependent, and the processor is further configured to:

in the case that the at least one second UE and the first UE are out of network coverage, determine an in-coverage UE as a relay UE for communication between the first UE and the network device; and

transmit, via the transceiver to the network device via the in-coverage UE, positioning result or measurement data associated with the first UE.
The first UE of claim 1, wherein the first positioning operation is network device-dependent, the UE is the first UE, and the processor is further configured to:

in the case that the network coverage state of the first UE changes to be out-of-coverage, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; and

in the case that the network device-independent positioning operation is determined, transmit, via the transceiver to the network device via an in-coverage UE, an indication of the network device-independent positioning operation; or

in the case that the network device-dependent positioning operation is determined, transmit, via the transceiver to the network device via an in-coverage UE, a request for the network device-dependent positioning operation and assistance information for a determination of a network device-dependent positioning operation or a network device-independent positioning operation for the first UE by the network device.
The first UE of claim 1, wherein the first UE is out of network coverage and an in-coverage UE is a relay UE for communication between the first UE and the network device prior to obtaining the change of network coverage state of the first UE, and the processor is further configured to:

in the case that the network coverage state of the first UE changes to be in-coverage, transmit, via the transceiver to the in-coverage UE, an indication of releasing a relay function.
A second user equipment (UE) comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

determine a change of network coverage state of the second UE; and

transmit, via the transceiver, an indication of the change of network coverage state to one of the following: a first UE, a third UE associated with a first positioning operation for the first UE or a network device.
The second UE of claim 9, wherein transmitting the indication of the change of network coverage state of the second UE comprises one of the following:

transmitting, via the transceiver, an indication that the network coverage state of the second UE changes to be in-coverage in the case that the second UE enters network coverage for a pre-defined time window; or

transmitting, via the transceiver to the first UE, an indication that the network coverage state of the second UE changes to be out-of-coverage in the case that the second UE moves out of network coverage.
The second UE of claim 9, wherein the processor is further configured to:

in the case that the second UE is in network coverage, receive, via the transceiver from the network device, an indication of operations to be performed by the third UE or an indication of releasing a server function; and

transmit, via the transceiver to the third UE, the indication of operations to be performed by the third UE or the indication of releasing a server function.
The second UE of claim 9, wherein the first positioning operation is network device-dependent, the second UE is in network coverage, and the processor is further configured to:

receive, via the transceiver from the first UE, an indication that the network coverage state of the first UE changes to be out-of-coverage; and

transmit, via the transceiver to the network device, the indication that the network coverage state of the first UE changes to be out-of-coverage.
A third user equipment (UE) comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive, via the transceiver, one of the following:

an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE, or

positioning session-related information associated with the first positioning operation or positioning request-related information; and

in the case that the indication of the change of network coverage state of the UE is received, determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE; or

in the case that the positioning request-related information or the positioning session-related information is received, perform a second positioning operation for the first UE based on the positioning request-related information or the positioning session-related information.
The third UE of claim 13, wherein the processor is further configured to:

receive, via the transceiver from the first UE or the second UE, assistance information, and

wherein the network device-dependent positioning operation or the network device-independent positioning operation is determined based on the indication of the change of network coverage state of the UE and the assistance information.
The third UE of claim 13, wherein the processor is further configured to:

receive, via the transceiver from the network device or an in-coverage UE, an indication of operations to be performed by the third UE or an indication of releasing a server function; and

perform the operations in the case that the indication of the operations is received; or

release the server function in the case that the indication of releasing the server function is received.
A network device comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive, via the transceiver from an in-coverage user equipment (UE) , an indication of a change of network coverage state of a UE, wherein the UE is a first UE or one of at least one second UE associated with a first positioning operation for the first UE; and

determine a network device-dependent positioning operation or a network device-independent positioning operation for the first UE.
The network device of claim 16, wherein the processor is further configured to:

receive, via the transceiver from the in-coverage UE, a request for a network device-dependent positioning operation.
The network device of claim 16, wherein the processor is further configured to:

in the case that the network device-dependent positioning operation is determined, determine one of the following:

performing the network device-dependent positioning operation with the at least one second UE;

reselecting second UEs for the network device-dependent positioning operation; or

aborting a sidelink positioning session and starting a Uu positioning session or a hybrid Uu and PC5 positioning session in the case that the first UE is in network coverage.
The network device of claim 16, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to:

receive, via the transceiver from the in-coverage UE, an indication of the network device-independent positioning operation.
The network device of claim 16, wherein the first positioning operation is network device-dependent, the network coverage state of the first UE changes to be out-of-coverage, and the processor is further configured to:

transmit, via the transceiver to the first UE via the in-coverage UE, an indication of a network device-independent positioning operation and positioning request-related information.