CN117242842A - Method and apparatus for supporting location services continuity - Google Patents

Abstract

The present disclosure relates to methods and apparatus for supporting location services continuity. An exemplary method includes receiving, by a wireless transmit/receive unit (WTRU), a configuration for supporting location services continuity during a handover. The method additionally includes supporting, by the WTRU, location service continuity based at least in part on the configuration by determining one or more transmissions to perform. The method also includes facilitating data link handoff by the radio access network by performing the one or more transmissions according to the configuration.

Description

Method and apparatus for supporting location services continuity

Cross Reference to Related Applications

The present application claims the benefit of U.S. provisional application number 63/257213 filed on day 2021, 10, and 19, the benefit of U.S. provisional application number 63/249199 filed on day 2021, 9, and the benefit of U.S. provisional application number 63/1688195 filed on day 2021, 3, and 30, each of which is incorporated herein by reference in its entirety.

Technical Field

The present disclosure relates to methods and apparatus for performing wireless communications, and in particular to supporting location service continuity.

Background

In 3GPP release 16, a set of SRS resources and SRS resources configured for positioning are specified.

Disclosure of Invention

In certain representative embodiments, methods, apparatus, and systems may be implemented that support location service continuity for Downlink (DL) based positioning.

In certain representative embodiments, methods, apparatus, and systems may be implemented that support location service continuity for Uplink (UL) based positioning.

In certain representative embodiments, methods, apparatus, and systems may be implemented that support location service continuity based on switching between different location methods.

In some representative embodiments, methods, apparatus, and systems may be implemented in which a WTRU switches from a first PRS configuration to a second PRS configuration based on PRS configurations of configurations associated with different base stations/gnbs/cells and thresholds after a Handover (HO).

Drawings

A more detailed understanding can be obtained from the following detailed description, which is given by way of example in connection with the accompanying drawings. As with the detailed description, the drawings in such figures are exemplary. Accordingly, the drawings and detailed description are not to be regarded as limiting, and other equally effective examples are possible and contemplated. Additionally, like reference numerals ("ref") in the drawings ("figures") refer to like elements, and wherein:

FIG. 1A is a system diagram illustrating an exemplary communication system in which one or more disclosed embodiments may be implemented;

fig. 1B is a system diagram illustrating an exemplary wireless transmit/receive unit (WTRU) that may be used within the communication system shown in fig. 1A in accordance with one or more embodiments;

fig. 1C is a system diagram illustrating an exemplary Radio Access Network (RAN) and an exemplary Core Network (CN) that may be used within the communication system shown in fig. 1A, in accordance with one or more embodiments;

fig. 1D is a system diagram illustrating another exemplary RAN and another exemplary CN that may be used in the communication system shown in fig. 1A in accordance with one or more embodiments;

fig. 2 is a system diagram illustrating a WTRU receiving a Downlink (DL) Positioning Reference Signal (PRS) from a target gNB when connected to a source gNB in accordance with one or more embodiments;

fig. 3 is a system diagram illustrating a WTRU receiving DL-PRS from a source gNB while connected to a target gNB in accordance with one or more embodiments;

fig. 4 is a system diagram illustrating a WTRU receiving DL-PRS from a source gNB and a target gNB during a Handover (HO) in accordance with one or more embodiments;

fig. 5 is an illustration depicting timing of operations before, during, and after a HO in accordance with one or more embodiments.

Fig. 6 is a flow diagram illustrating a representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 7 is a flow diagram illustrating another representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 8 is a flow diagram illustrating a further representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 9 is a flow diagram illustrating an additional representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 10 is a flow diagram illustrating a further representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 11 is a flow diagram illustrating a further representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 12 is a flow diagram illustrating another additional representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 13 is a flow diagram illustrating yet another representative method implemented by a WTRU in accordance with one or more embodiments;

fig. 14 is a flow diagram illustrating a further representative method implemented by a WTRU in accordance with one or more embodiments; and is also provided with

Fig. 15 is a flow diagram illustrating yet another additional representative method implemented by a WTRU in accordance with one or more embodiments.

Detailed Description

Introduction to the invention

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments and/or examples disclosed herein. However, it should be understood that such embodiments and examples may be practiced without some or all of the specific details set forth herein. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the description below. Furthermore, embodiments and examples not specifically described herein may be practiced in place of or in combination with embodiments and other examples that are explicitly, implicitly, and/or inherently described, disclosed, or otherwise provided (collectively, "provided").

Exemplary network for implementing embodiments

Fig. 1A is a schematic diagram illustrating an exemplary communication system 100 in which one or more disclosed embodiments may be implemented. Communication system 100 may be a multiple-access system that provides content, such as voice, data, video, messages, broadcasts, etc., to a plurality of wireless users. Communication system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, communication system 100 may employ one or more channel access methods, such as Code Division Multiple Access (CDMA), time Division Multiple Access (TDMA), frequency Division Multiple Access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word Discrete Fourier Transform (DFT) spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter Bank Multicarrier (FBMC), and the like.

As shown in fig. 1A, the communication system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, 102d, RANs 104/113, CNs 106/115, public Switched Telephone Networks (PSTN) 108, the internet 110, and other networks 112, although it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment. As an example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a "station" and/or a "STA") may be configured to transmit and/or receive wireless signals and may include User Equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, pagers, cellular telephones, personal Digital Assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hot spot or Mi-Fi devices, internet of things (IoT) devices, watches or other wearable devices, head Mounted Displays (HMDs), vehicles, drones, medical devices and applications (e.g., tele-surgery), industrial devices and applications (e.g., robots and/or other wireless devices operating in an industrial and/or automated processing chain environment), consumer electronic devices, devices operating on a commercial and/or industrial wireless network, and the like. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

Communication system 100 may also include base station 114a and/or base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106/115, the internet 110, and/or the other networks 112. By way of example, the base stations 114a, 114B may be Base Transceiver Stations (BTSs), node bs, evolved node bs, home evolved node bs, gnbs, NR node bs, site controllers, access Points (APs), wireless routers, and the like. Although the base stations 114a, 114b are each depicted as a single element, it should be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and/or network elements.

Base station 114a may be part of RAN 104/113 that may also include other base stations and/or network elements (not shown), such as Base Station Controllers (BSCs), radio Network Controllers (RNCs), relay nodes, and the like. Base station 114a and/or base station 114b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as cells (not shown). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage of wireless services to a particular geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with base station 114a may be divided into three sectors. Thus, in an embodiment, the base station 114a may include three transceivers, i.e., one for each sector of a cell. In an embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of a cell. For example, beamforming may be used to transmit and/or receive signals in a desired spatial direction.

The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio Frequency (RF), microwave, centimeter wave, millimeter wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable Radio Access Technology (RAT).

More specifically, as noted above, communication system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, or the like. For example, a base station 114a in the RAN 104/113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) terrestrial radio access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interfaces 115/116/117.WCDMA may include communication protocols such as High Speed Packet Access (HSPA) and/or evolved HSPA (hspa+). HSPA may include high speed Downlink (DL) packet access (HSDPA) and/or high speed Uplink (UL) packet access (HSUPA).

In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as evolved UMTS terrestrial radio access (E-UTRA), which may use Long Term Evolution (LTE) and/or LTE-advanced (LTE-a) and/or LTE-advanced Pro (LTE-a Pro) to establish the air interface 116.

In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access that may use a new air interface (NR) to establish the air interface 116.

In embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, e.g., using a Dual Connectivity (DC) principle. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and/or transmissions sent to/from multiple types of base stations (e.g., enbs and gnbs).

In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., wireless fidelity (WiFi)), IEEE 802.16 (i.e., worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000 1X, CDMA EV-DO, tentative standard 2000 (IS-2000), tentative standard 95 (IS-95), tentative standard 856 (IS-856), global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE), GSM EDGE (GERAN), and the like.

The base station 114B in fig. 1A may be, for example, a wireless router, home node B, home evolved node B, or access point, and may utilize any suitable RAT to facilitate wireless connections in local areas such as business, home, vehicle, campus, industrial facility, air corridor (e.g., for use by drones), road, etc. In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a Wireless Local Area Network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a Wireless Personal Area Network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-a Pro, NR, etc.) to establish a pico cell or femto cell. As shown in fig. 1A, the base station 114b may have a direct connection with the internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106/115.

The RANs 104/113 may communicate with the CNs 106/115, which may be any type of network configured to provide voice, data, application, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102 d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, delay requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106/115 may provide call control, billing services, mobile location based services, prepaid calls, internet connections, video distribution, etc., and/or perform advanced security functions such as user authentication. Although not shown in fig. 1A, it should be appreciated that the RANs 104/113 and/or CNs 106/115 may communicate directly or indirectly with other RANs that employ the same RAT as the RANs 104/113 or a different RAT. For example, in addition to being connected to the RAN 104/113 that may utilize NR radio technology, the CN 106/115 may also communicate with another RAN (not shown) employing GSM, UMTS, CDMA, wiMAX, E-UTRA, or WiFi radio technology.

The CN 106/115 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and/or other networks 112.PSTN 108 may include circuit-switched telephone networks that provide Plain Old Telephone Services (POTS). The internet 110 may include a global system for interconnecting computer networks and devices using common communication protocols, such as Transmission Control Protocol (TCP), user Datagram Protocol (UDP), and/or Internet Protocol (IP) in the TCP/IP internet protocol suite. Network 112 may include wired and/or wireless communication networks owned and/or operated by other service providers. For example, the network 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RANs 104/113 or a different RAT.

Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in fig. 1A may be configured to communicate with a base station 114a, which may employ a cellular-based radio technology, and with a base station 114b, which may employ an IEEE 802 radio technology.

Fig. 1B is a system diagram illustrating an exemplary WTRU 102. As shown in fig. 1B, the WTRU 102 may include a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a Global Positioning System (GPS) chipset 136, and/or other peripheral devices 138, etc. It should be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a Digital Signal Processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs) circuits, any other type of Integrated Circuit (IC), a state machine, or the like. The processor 118 may perform signal coding, data processing, power control, input/output processing, and/or any other functions that enable the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to a transceiver 120, which may be coupled to a transmit/receive element 122. Although fig. 1B depicts the processor 118 and the transceiver 120 as separate components, it should be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

The transmit/receive element 122 may be configured to transmit signals to and receive signals from a base station (e.g., base station 114 a) over the air interface 116. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In one embodiment, the transmit/receive element 122 may be an emitter/detector configured to emit and/or receive, for example, IR, UV, or visible light signals. In yet another embodiment, the transmit/receive element 122 may be configured to transmit and/or receive RF and optical signals. It should be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals.

Although the transmit/receive element 122 is depicted as a single element in fig. 1B, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit/receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

The transceiver 120 may be configured to modulate signals to be transmitted by the transmit/receive element 122 and demodulate signals received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. For example, therefore, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs (such as NR and IEEE 802.11).

The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker/microphone 124, a keypad 126, and/or a display/touchpad 128, such as a Liquid Crystal Display (LCD) display unit or an Organic Light Emitting Diode (OLED) display unit. The processor 118 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. Further, the processor 118 may access information from and store data in any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include Random Access Memory (RAM), read Only Memory (ROM), a hard disk, or any other type of memory storage device. Removable memory 132 may include a Subscriber Identity Module (SIM) card, a memory stick, a Secure Digital (SD) memory card, and the like. In other embodiments, the processor 118 may never physically locate memory access information on the WTRU 102, such as on a server or home computer (not shown), and store the data in that memory.

The processor 118 may receive power from the power source 134 and may be configured to distribute and/or control power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry battery packs (e.g., nickel cadmium (NiCd), nickel zinc (NiZn), nickel metal hydride (NiMH), lithium ion (Li-ion), etc.), solar cells, fuel cells, and the like.

The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of information from the GPS chipset 136, the WTRU 102 may receive location information from base stations (e.g., base stations 114a, 114 b) over the air interface 116 and/or determine its location based on the timing of signals received from two or more nearby base stations. It should be appreciated that the WTRU 102 may obtain location information by any suitable location determination method while remaining consistent with an embodiment.

The processor 118 may also be coupled to other peripheral devices 138, which may include one or more software modules and/or hardware modules that provide additional features, functionality, and/or wired or wireless connections. For example, the number of the cells to be processed, peripheral devices 138 may include accelerometers, electronic compasses, satellite transceivers, digital cameras (for photographs and/or video), universal Serial Bus (USB) ports, vibrating devices, television transceivers, hands-free headsets, wireless communications devices, and the like,Modules, frequency Modulation (FM) radio units, digital music players, media players, video game player modules, internet browsers, virtual reality and/or augmented reality (VR/AR) devices, activity trackers, and the like. The peripheral device 138 may include one or more sensors, which may be one or more of the following: gyroscopes, accelerometers, hall effect sensors, magnetometers, orientation sensors, proximity sensors, temperature sensors, time sensors; a geographic position sensor; altimeters, light sensors, touch sensors, magnetometers, barometers, gesture sensors, biometric sensors, and/or humidity sensors.

WTRU 102 may include a full duplex radio for which transmission and reception of some or all signals (e.g., associated with a particular subframe for UL (e.g., for transmission) and DL (e.g., for reception)) may be concurrent and/or simultaneous. The full duplex radio station may include an interference management unit 139 for reducing and/or substantially eliminating self-interference via hardware (e.g., choke) or via signal processing by a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which some or all signals are transmitted and received (e.g., associated with a particular subframe for UL (e.g., for transmitting) or DL (e.g., for receiving).

Fig. 1C is a system diagram illustrating a RAN 104 and a CN 106 according to one embodiment. As noted above, the RAN 104 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 using an E-UTRA radio technology. RAN 104 may also communicate with CN 106.

RAN 104 may include enode bs 160a, 160B, 160c, but it should be understood that RAN 104 may include any number of enode bs while remaining consistent with an embodiment. The enode bs 160a, 160B, 160c may each include one or more transceivers to communicate with the WTRUs 102a, 102B, 102c over the air interface 116. In an embodiment, the evolved node bs 160a, 160B, 160c may implement MIMO technology. Thus, the enode B160 a may use multiple antennas to transmit wireless signals to the WTRU 102a and/or to receive wireless signals from the WTRU 102a, for example.

Each of the evolved node bs 160a, 160B, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and/or DL, and the like. As shown in fig. 1C, the enode bs 160a, 160B, 160C may communicate with each other over an X2 interface.

The CN 106 shown in fig. 1C may include a Mobility Management Entity (MME) 162, a Serving Gateway (SGW) 164, and a Packet Data Network (PDN) gateway (or PGW) 166. Although each of the foregoing elements are depicted as part of the CN 106, it should be understood that any of these elements may be owned and/or operated by an entity other than the CN operator.

The MME 162 may be connected to each of the evolved node bs 162a, 162B, 162c in the RAN 104 via an S1 interface and may function as a control node. For example, the MME 162 may be responsible for authenticating the user of the WTRUs 102a, 102b, 102c, bearer activation/deactivation, selecting a particular serving gateway during initial attach of the WTRUs 102a, 102b, 102c, and the like. MME 162 may provide control plane functionality for switching between RAN 104 and other RANs (not shown) employing other radio technologies such as GSM and/or WCDMA.

SGW 164 may be connected to each of the evolved node bs 160a, 160B, 160c in RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102 c. The SGW 164 may perform other functions such as anchoring user planes during inter-enode B handover, triggering paging when DL data is available to the WTRUs 102a, 102B, 102c, managing and storing the contexts of the WTRUs 102a, 102B, 102c, etc.

The SGW 164 may be connected to a PGW 166 that may provide the WTRUs 102a, 102b, 102c with access to a packet switched network, such as the internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to a circuit-switched network (such as the PSTN 108) to facilitate communications between the WTRUs 102a, 102b, 102c and legacy landline communication devices. For example, the CN 106 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and/or wireless networks owned and/or operated by other service providers.

Although the WTRU is depicted in fig. 1A-1D as a wireless terminal, it is contemplated that in some representative embodiments such a terminal may use a wired communication interface with a communication network (e.g., temporarily or permanently).

In representative embodiments, the other network 112 may be a WLAN.

A WLAN in an infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) for the BSS and one or more Stations (STAs) associated with the AP. The AP may have access or interface to a Distribution System (DS) or another type of wired/wireless network that carries traffic to and/or from the BSS. Traffic originating outside the BSS and directed to the STA may arrive through the AP and may be delivered to the STA. Traffic originating from the STA and leading to a destination outside the BSS may be sent to the AP to be delivered to the respective destination. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may pass the traffic to the destination STA. Traffic between STAs within a BSS may be considered and/or referred to as point-to-point traffic. Point-to-point traffic may be sent between (e.g., directly between) the source and destination STAs using Direct Link Setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z Tunnel DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and STAs (e.g., all STAs) within or using the IBSS may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad-hoc" communication mode.

When using the 802.11ac infrastructure mode of operation or similar modes of operation, the AP may transmit beacons on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20MHz wide bandwidth) or a width dynamically set by signaling. The primary channel may be an operating channel of the BSS and may be used by STAs to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access/collision avoidance (CSMA/CA) may be implemented, for example, in an 802.11 system. For CSMA/CA, STAs (e.g., each STA), including the AP, may listen to the primary channel. If the primary channel is listened to/detected by a particular STA and/or determined to be busy, the particular STA may backoff. One STA (e.g., only one station) may transmit at any given time in a given BSS.

High Throughput (HT) STAs may communicate using 40MHz wide channels, for example, via a combination of a primary 20MHz channel with an adjacent or non-adjacent 20MHz channel to form a 40MHz wide channel.

Very High Throughput (VHT) STAs may support channels that are 20MHz, 40MHz, 80MHz, and/or 160MHz wide. 40MHz and/or 80MHz channels may be formed by combining consecutive 20MHz channels. The 160MHz channel may be formed by combining 8 consecutive 20MHz channels, or by combining two non-consecutive 80MHz channels (this may be referred to as an 80+80 configuration). For the 80+80 configuration, after channel coding, the data may pass through a segment parser that may split the data into two streams. An Inverse Fast Fourier Transform (IFFT) process and a time domain process may be performed on each stream separately. These streams may be mapped to two 80MHz channels and data may be transmitted by the transmitting STA. At the receiver of the receiving STA, the operations described above for the 80+80 configuration may be reversed and the combined data may be sent to a Medium Access Control (MAC).

The 802.11af and 802.11ah support modes of operation below 1 GHz. Channel operating bandwidth and carrier are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11 ac. The 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the television white space (TVWS) spectrum, and the 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to representative embodiments, 802.11ah may support meter type control/machine type communications, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including supporting (e.g., supporting only) certain bandwidths and/or limited bandwidths. MTC devices may include batteries with battery lives above a threshold (e.g., to maintain very long battery lives).

WLAN systems that can support multiple channels, and channel bandwidths such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and/or limited by STAs from all STAs operating in the BSS (which support a minimum bandwidth mode of operation). In the example of 802.11ah, for STAs (e.g., MTC-type devices) that support (e.g., only) 1MHz mode, the primary channel may be 1MHz wide, even though the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and/or other channel bandwidth modes of operation. The carrier sense and/or Network Allocation Vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because the STA (supporting only 1MHz mode of operation) is transmitting to the AP, the entire available frequency band may be considered busy even though most of the frequency band remains idle and possibly available.

The available frequency band for 802.11ah in the united states is 902MHz to 928MHz. In korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

Fig. 1D is a system diagram illustrating RAN 113 and CN 115 according to one embodiment. As noted above, RAN 113 may employ NR radio technology to communicate with WTRUs 102a, 102b, 102c over an air interface 116. RAN 113 may also communicate with CN 115.

RAN 113 may include gnbs 180a, 180b, 180c, but it should be understood that RAN 113 may include any number of gnbs while remaining consistent with an embodiment. Each of the gnbs 180a, 180b, 180c may include one or more transceivers to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. In an embodiment, the gnbs 180a, 180b, 180c may implement MIMO technology. For example, gnbs 180a, 180b may utilize beamforming to transmit signals to and/or receive signals from gnbs 180a, 180b, 180 c. Thus, the gNB 180a may use multiple antennas to transmit wireless signals to the WTRU 102a and/or receive wireless signals from the WTRU 102a, for example. In an embodiment, the gnbs 180a, 180b, 180c may implement carrier aggregation techniques. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on the unlicensed spectrum while the remaining component carriers may be on the licensed spectrum. In embodiments, the gnbs 180a, 180b, 180c may implement coordinated multipoint (CoMP) techniques. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and/or gNB 180 c).

The WTRUs 102a, 102b, 102c may communicate with the gnbs 180a, 180b, 180c using transmissions associated with the scalable parameter sets. For example, the OFDM symbol interval and/or OFDM subcarrier interval may vary from one transmission to another, from one cell to another, and/or from one portion of the wireless transmission spectrum to another. The WTRUs 102a, 102b, 102c may communicate with the gnbs 180a, 180b, 180c using various or scalable length subframes or Transmission Time Intervals (TTIs) (e.g., including different numbers of OFDM symbols and/or continuously varying absolute time lengths).

The gnbs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in an independent configuration and/or in a non-independent configuration. In a standalone configuration, the WTRUs 102a, 102B, 102c may communicate with the gnbs 180a, 180B, 180c while also not accessing other RANs (e.g., such as the enode bs 160a, 160B, 160 c). In an independent configuration, the WTRUs 102a, 102b, 102c may use one or more of the gnbs 180a, 180b, 180c as mobility anchor points. In an independent configuration, the WTRUs 102a, 102b, 102c may use signals in unlicensed frequency bands to communicate with the gnbs 180a, 180b, 180 c. In a non-standalone configuration, the WTRUs 102a, 102B, 102c may communicate or connect with the gnbs 180a, 180B, 180c, while also communicating or connecting with other RANs (such as the enode bs 160a, 160B, 160 c). For example, the WTRUs 102a, 102B, 102c may implement DC principles to communicate with one or more gnbs 180a, 180B, 180c and one or more enodebs 160a, 160B, 160c substantially simultaneously. In a non-standalone configuration, the enode bs 160a, 160B, 160c may serve as mobility anchors for the WTRUs 102a, 102B, 102c, and the gnbs 180a, 180B, 180c may provide additional coverage and/or throughput for serving the WTRUs 102a, 102B, 102 c.

Each of the gnbs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, HO decisions, scheduling of users in UL and/or DL, support of network slices, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards User Plane Functions (UPFs) 184a, 184b, routing of control plane information towards access and mobility management functions (AMFs) 182a, 182b, and so on. As shown in fig. 1D, gnbs 180a, 180b, 180c may communicate with each other through an Xn interface.

The CN 115 shown in fig. 1D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. Although each of the foregoing elements are depicted as part of the CN 115, it should be understood that any of these elements may be owned and/or operated by entities other than the CN operator.

AMFs 182a, 182b may be connected to one or more of gNB 180a, 180b, 180c in RAN 113 via an N2 interface and may function as a control node. For example, the AMFs 182a, 182b may be responsible for: authenticating a user of the WTRU 102a, 102b, 102c, supporting network slicing (e.g., handling of different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, managing a registration area, termination of non-access stratum (NAS) signaling, mobility management, etc. The AMFs 182a, 182b may use network slices to customize CN support for the WTRUs 102a, 102b, 102c based on the type of service used by the WTRUs 102a, 102b, 102 c. For example, different network slices may be established for different use cases, such as services relying on ultra high reliability low latency (URLLC) access, services relying on enhanced mobile broadband (eMBB) access, services for Machine Type Communication (MTC) access, and so on. The AMFs 182A, 182B may provide control plane functionality for switching between the RAN 113 and other RANs (not shown) employing other radio technologies, such as LTE, LTE-A, LTE-a Pro, and/or non-third generation partnership project (3 GPP) access technologies, such as WiFi.

The SMFs 183a, 183b may be connected to AMFs 182a, 182b in the CN 115 via an N11 interface. The SMFs 183a, 183b may also be connected to UPFs 184a, 184b in the CN 115 via an N4 interface. SMFs 183a, 183b may select and control UPFs 184a, 184b and configure traffic routing through UPFs 184a, 184b. The SMFs 183a, 183b may perform other functions such as managing and assigning UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing DL data notifications, etc. The PDU session type may be IP-based, non-IP-based, ethernet-based, etc.

UPFs 184a, 184b may be connected to one or more of the gnbs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to a packet-switched network, such as the internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. UPFs 184, 184b may perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multi-host PDU sessions, handling user plane QoS, buffering DL packets, providing mobility anchoring, and the like.

The CN 115 may facilitate communications with other networks. For example, the CN 115 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and/or wireless networks owned and/or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may connect to the local Data Networks (DNs) 185a, 185b through the UPFs 184a, 184b through an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

In view of fig. 1A-1D and the corresponding descriptions of fig. 1A-1D, one or more or all of the functions described herein with reference to one or more of the following may be performed by one or more emulation devices (not shown): the WTRUs 102a-102d, base stations 114a-114B, eNodeBs 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMFs 182a-182B, UPFs 184a-184B, SMFs 183a-183B, DNs 185a-185B, and/or any other devices described herein. The emulated device may be one or more devices configured to emulate one or more or all of the functions described herein. For example, the emulation device may be used to test other devices and/or analog network and/or WTRU functions.

The simulation device may be designed to enable one or more tests of other devices in a laboratory environment and/or an operator network environment. For example, the one or more emulation devices can perform one or more or all of the functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices can perform one or more functions or all functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network. The emulation device may be directly coupled to another device for testing purposes and/or may perform testing using over-the-air wireless communications.

The one or more emulation devices can perform one or more (including all) functions while not being implemented/deployed as part of a wired and/or wireless communication network. For example, the simulation device may be used in a test laboratory and/or a test scenario in a non-deployed (e.g., test) wired and/or wireless communication network in order to enable testing of one or more components. The one or more simulation devices may be test equipment. Direct RF coupling and/or wireless communication via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation device to transmit and/or receive data.

Supporting location services continuity

Location services in legacy systems

In release 16, DL, UL and DL and UL positioning methods are used. In the DL positioning method, PRSs may be sent from multiple TX/RX points (TRPs) to WTRUs. The WTRU will observe multiple reference signals and measure the time difference of arrival between a pair of PRSs. The WTRU then returns the measured Reference Signal Time Difference (RSTD) to the Location Management Function (LMF). Further, the WTRU may return a measured Reference Signal Received Power (RSRP) for each PRS. Based on the returned measurements, the LMF locates the WTRU. Alternatively, the WTRU may report RSRP for the angle-based DL positioning method.

LMFs are non-limiting examples of nodes or entities (e.g., network nodes or entities) that may be used for or support positioning. Any other node or entity may replace the LMF and remain consistent with the present disclosure. In the UL positioning method, the WTRU sends a Sounding Reference Signal (SRS) configured by Radio Resource Control (RRC) for positioning to a Receiving Point (RP). For the timing-based approach, the RP measures the relative time of arrival (RTOA) for the received SRS and reports the measurements to the LMF. The WTRU may report RSRP for SRS. In the angle-based UL positioning method, the RP measures the angle of arrival and reports to the LMF.

Finally, in UL and DL positioning methods, the WTRU measures the Rx-Tx time difference between the received PRS and the transmitted SRS. The Rx-Tx time difference is reported from the WTRU to the LMF. The WTRU may also report RSRP for the measurements of PRS. Similarly, at the TRP, the Rx-Tx difference between the received SRS and the transmitted PRS is calculated.

In the present disclosure, various positioning methods are considered/implemented. For example, a "DL positioning method" may refer to any positioning method using DL reference signals (such as PRS). The WTRU receives multiple reference signals from a Transmission Point (TP) and measures DL RSTD and/or RSRP. Examples of DL positioning methods are DL-angle of departure (AoD) or DL-time difference of arrival (TDOA) positioning. In addition, the "UL positioning method" may refer to any positioning method using UL reference signals (such as SRS for positioning). The WTRU transmits SRS to multiple RPs and the RPs measure UL RTOA and/or RSRP. Examples of UL positioning methods are UL-TDOA or UL-AoA positioning. In addition, the "DL and UL positioning methods" may refer to any positioning method that uses both UL reference signals and DL reference signals for positioning. In one example, the WTRU transmits SRS to multiple TRPs and the gNB measures the Rx-Tx time difference. The gNB may measure RSRP for the received SRS. The WTRU measures an Rx-Tx time difference for PRSs transmitted from a plurality of TRPs. The WTRU may measure RSRP for the received PRS. The Rx-TX difference and possibly the RSRP measured at the WTRU and the gNB are used to calculate the round trip time. Here, the Rx and Tx difference refers to a difference between an arrival time of a reference signal transmitted by the TRP and a transmission time of the reference signal transmitted from the WTRU. An example of DL and UL positioning methods is multi-Round Trip Time (RTT) positioning.

In this disclosure, a "network" may include one or more AMFs, one or more LMFs, and/or one or more next generation radio access networks (NG-RANs). Release 16/17 positioning procedure for DL-PRS measurements in RRC CONNECTED state allows for limited levels of intra-gcb mobility (within the coverage area of TRPs belonging to the same gcb) and inter-gcb mobility (for the case where multiple gcbs use the same PRS configuration). Reporting measurement or location information to the LMF via the serving gNB/cell support. Location service continuity for UL-based positioning during/after HO is not supported in release 16/17, where the WTRU may continue to use the same sounding reference signal (SRSp) configuration for positioning.

3GPP release 17 supports WTRU-based and LMF-based positioning for RAT-related positioning. For RAT-related positioning, WTRU behavior and procedures for supporting positioning service continuity with low latency and high accuracy are unknown.

For DL-based positioning (where the WTRU determines positioning information based on measurements of DL-PRS), the WTRU needs to request or may request a new PRS configuration when the WTRU experiences a data link HO from the source gNB to the target gNB and when PRS configurations used by the source and target gnbs are different. Sending a request to the LMF via the target gNB and receiving a new PRS configuration while performing a data link HO may result in increased delay and possible positioning gaps (e.g., positioning measurements may not be available). In addition, measurements cannot be performed on PRSs received from the target gNB (the WTRU may receive the strongest PRS from the target gNB compared to other gnbs) until a new PRS configuration is available at the WTRU, which may also result in loss of positioning accuracy at the WTRU. Furthermore, even when the target gNB uses the same PRS configuration as the source gNB, measurement gaps configured by the source gNB via RRC signaling may be released during the data link HO and reconfigured by the target gNB after the HO. This may also lead to possible positioning gaps and higher delays associated with the measurement gap configuration.

For UL-based positioning, time/frequency resource configuration for UL-SRSp is configured in the WTRU by the serving gNB. The SRSp configuration provided by the source gNB may be released when the WTRU experiences a data link HO. Subsequently, the delay in receiving the new SRSp configuration from the target gNB after HO may be high. In this case, a positioning gap and loss of positioning accuracy may occur because the TRP associated with the target gNB cannot measure the new SRSp sent by the WTRU.

For DL and UL based positioning (e.g., multi-RTT positioning methods), the set of TRPs that may transmit/receive PRS/SRSp may vary based on WTRU mobility. This may also result in incorrect estimation of WTRU to TRP distance, possible incorrect positioning calculations, and loss of positioning accuracy.

Generally, existing (release 16/17) methods for supporting RAT-related positioning may result in high delays and positioning gaps (duration of positioning measurement unavailable) because the LMF/RAN triggers delays in PRS/SRSp transmissions from the target cell and/or WTRU. In this regard, one problem to be solved is or may be how to ensure location service continuity so that QoS associated with location (e.g., high accuracy, low latency, low signaling overhead) may be supported during WTRU mobility.

Representative positioning solution/procedure

With respect to reference signals in this disclosure, it should be noted that "SRS for positioning" refers herein to SRS signals/transmissions for positioning. The resources for the positioned SRS (SRSp) may be defined (e.g., signaled) by the RRC. In release 16, a set of SRS resources and SRS resources configured for positioning are specified. However, in some embodiments "SRS for positioning" or "SRS" may include various types of signals. For example, the SRS may be an SRS configured under SRS-PosResourceServer-r 16 and SRS-PosResource-r 16. Alternatively or additionally, the SRS can be an SRS configured under SRS-Resource and SRS-Resource. Alternatively or additionally, the SRS may be an SRS that is not configured under SRS-PosResourceSet-r16 and SRS-PosResource-r 16. Alternatively or additionally, the SRS can be an SRS that is not configured under SRS-ResourceNet and SRS-Resource. Alternatively or additionally, the SRS may be an SRS that is not associated with SRS-PosResourceNet-r 16, SRS-PosResource-r16, SRS-ResourceNet, or SRS-Resource. Alternatively or additionally, the SRS may be an UL reference signal associated with the positioning. Alternatively or additionally, the SRS may be a demodulation reference signal (DM-RS) for the UL. Alternatively or additionally, the SRS may be a Phase Tracking Reference Signal (PTRS) for the UL.

For brevity, the SRS used for positioning is denoted as "SRSp". In addition, PRSs or SRS used in the present disclosure are not limited to RSs used for positioning. The disclosed methods may be applied to any DL or UL reference signal or may be used with it.

With respect to positioning configurations in the present disclosure, a positioning configuration may include a set of information related to positioning measurements and/or SRSp transmissions. Various types of information may be included in the positioning configuration. For example, the positioning configuration may include information about the positioning method used (e.g., DL-TDOA, UL-TDOA, DL-AoD, UL-AoA, multiple RTTs). Additionally or alternatively, the positioning configuration may include information regarding PRS configuration, SRSp configuration, and/or UL resources (e.g., physical Random Access Channel (PRACH), physical UL Shared Channel (PUSCH), and/or Physical Uplink Control Channel (PUCCH)) to report positioning measurements. Additionally or alternatively, the positioning configuration may include information regarding one or more thresholds for determining positioning measurement quality and/or positioning mode of operation (e.g., starting a positioning mode of operation).

With respect to PRS resource configurations, this type of configuration may include various types of information. For example, the PRS configuration may include information about PRS resource IDs, PRS sequence IDs, and/or other IDs used to generate PRS sequences. Alternatively or additionally, the PRS configuration may include information regarding PRS resource element offsets, PRS resource slot offsets, and/or PRS symbol offsets. Alternatively or additionally, the PRS configuration may include information regarding PRS quasi co-sited (QCL) information, PRS resource set IDs, and/or PRS resource lists in the resource set. Alternatively or additionally, the PRS configuration may include information regarding a number of PRS symbols, a muting pattern for PRS, muting parameters (such as a repetition factor), and/or muting options. Alternatively or additionally, PRS configuration may include information regarding PRS resource power, periodicity of PRS transmissions, spatial direction information of PRS transmissions (e.g., beam information, transmission angle) and/or spatial direction information of UL RS reception (e.g., beam ID, angle of arrival (AoA) for receiving UL RS).

Regarding SRSp resource configuration, this type of configuration may include various types of information. For example, the SRSp resource configuration may include information about a resource ID, a comb offset value, a cyclic shift value, and/or a starting position in the frequency domain. Alternatively or additionally, the SRSp resource configuration may include information regarding the number of SRSp symbols, a shift in the frequency domain of the SRSp, a frequency hopping pattern, and/or a type of SRSp (e.g., aperiodic, semi-persistent, or periodic). Alternatively or additionally, the SRSp resource configuration may include information about a sequence ID used to generate the SRSp or other IDs used to generate the SRSp sequence. Alternatively or additionally, the SRSp resource configuration may include spatial relationship information indicating with which reference signal the SRSp is spatially related. Alternatively or additionally, the SRSp resource configuration may include a resource set ID, a list of SRSp resources in the resource set, and/or transmission power related information. Alternatively or additionally, the SRSp resource configuration may include path loss reference information, which may include an index for a Synchronization Signal Block (SSB), a Channel State Information (CSI) reference signal (CSI-RS), and/or PRS. Alternatively or additionally, the SRSp resource configuration may include periodicity of SRSp transmissions and/or spatial direction information (e.g., beam information, transmission angle) of SRSp transmissions. Alternatively or additionally, the SRSp resource configuration may include spatial direction information received by the DL RS (e.g., beam ID, angle of arrival for receiving the DL RS). As part of this configuration, the WTRU may receive information related to a cell ID, a global cell ID, and/or a TRP ID associated with the PRS. For example, the TRP transmitting PRS is identified by a TRP ID, which may belong to the cell identified by the cell ID. The WTRU may be configured with timing information, such as a subframe number (SFN) offset for PRS or SRSp transmissions. An offset may be introduced or an offset may be introduced to prevent the WTRU from receiving overlapping PRSs in the time domain.

Representative procedure/method for supporting location service continuity for DL-based location

In one class of solutions, the WTRU performs positioning service continuity based on PRS/Radio Resource Management (RRM) measurements. For example, the WTRU may initiate and perform location service continuity by sending a request for a new PRS configuration to the network (e.g., LMF and/or RAN) when triggered by one or more configured location service continuity conditions. Location service continuity may refer to changing and/or updating one or more PRS configurations associated with different TRP/gNB/cells in a network at a WTRU. For example, due to WTRU mobility and/or when the WTRU experiences a data link HO, the PRS configuration used may be changed to make the measurements. In another example, location service continuity may not be directly attributable to WTRU mobility, where when the WTRU is able to detect one or more new TRP/gNB/cells (e.g., the WTRU is able to receive RSs from the new TRP/gNB/cells due to congestion being cleared), the PRS configuration used may be changed to make the measurements. Hereinafter, the terms "location service continuity" and "location mobility" are used interchangeably to refer to any procedure that may cause PRS configurations used at WTRUs and/or networks to change/update based on mobility and/or non-mobility events/triggers/conditions. In addition, hereinafter, the term "new PRS configuration" may also refer to "an update to a PRS configuration," where an existing PRS configuration at a WTRU may be updated or replaced with a new/different PRS configuration, or may at least partially contain some overlap with an existing PRS configuration.

LMFs are non-limiting examples of nodes or entities (e.g., network nodes or entities) that may be used for or support positioning. Any other node or entity may replace the LMF and remain consistent with the present disclosure.

In one example, location service continuity may be performed by the WTRU independent of the data link HO. Alternatively, the location service continuity may be performed together with or during the data link HO. The WTRU may send a request for assistance information and/or configuration updates, where the assistance information/configuration updates may include PRS configurations associated with neighbor/target cells. In this case, the WTRU may send the request to the network via the serving gNB, for example, while in RRC CONNECTED or RRC INACTIVE state.

Upon receiving the new PRS configuration from the network, the WTRU may perform positioning measurements using the new configuration based on one or more positioning initiation triggers. A positioning initiation trigger may be received by the WTRU from a network (e.g., an LMF and/or RAN entity and/or base station) indicating when to use a new PRS configuration and/or when to cease using an existing PRS configuration. For example, the WTRU may receive a positioning initiation trigger from the network and a new PRS configuration and/or preconfigured in the WTRU via other procedures (e.g., other LTE Positioning Protocol (LPP) procedures or location request procedures).

In one example, the WTRU may send a request for a new PRS configuration before or during a conventional data link/RRC connection HO such that the PRS configuration of the target cell may be received and/or used for PRS measurements before the HO. In this case, PRS configurations may be received by the WTRU from the serving/source gNB. This will also minimize the potential for delays associated with sending the request and receiving the new PRS configuration and avoid any positioning gaps where the WTRU may continuously perform positioning measurements during mobility without interruption. In another example, the WTRU may send the request during and/or while performing the data link HO, and may receive a new PRS configuration from the target gNB.

In one scenario, a WTRU may send a request for a new PRS configuration in cases of inter-gNB mobility where a source/serving TRP/gNB and a target TRP/gNB may be configured with different PRS configurations. In this case, the WTRU may be initially configured with the first PRS configuration when connected to the source/serving gNB. For example, the first PRS configuration may be received by the WTRU via assistance information from an LMF or via a System Information Block (SIB) from a source gNB. The WTRU may be configured with a first measurement gap configuration by the serving gNB for performing DL PRS measurements. The WTRU may also be configured with a second measurement gap configuration for performing RRM measurements, which may include, for example, measuring CSI-RS, SSB, and/or neighbor cell beams. In this case, for example, the first measurement gap configuration and the second measurement gap configuration may span non-overlapping time/frequency resources, or span one or more overlapping time/frequency resources.

In another scenario related to mobility within the gNB (where the source TRP and the target TRP may be under control of the same gNB), the WTRU may send a request for a new PRS configuration associated with the target TRP. When the target TRP is not configured with the PRS configuration currently configured in the WTRU, the WTRU may send the request directly to the serving gNB via the source TRP or to the LMF.

In the gNB intra/inter mobility scenario, the WTRU may detect unavailability of a suitable PRS configuration and/or use of a different PRS configuration at the target TRP/gNB/cell based on existing PRS configurations available at the WTRU. In this case, the WTRU may identify whether the target/neighbor cell uses the same or different PRS configuration based on a mapping of the cell IDs of the target/neighbor cell determined by the WTRU and different cell IDs associated with existing PRS configurations in the assistance information.

In some examples, the WTRU may support a location service continuity procedure with LPP. For example, a WTRU configured with one or more PRS configurations (e.g., indicating PRS information, patterns, and/or parameters) for positioning may perform positioning service continuity during mobility (e.g., HO procedure and/or re-establishment procedure, etc.) when supporting at least one LPP session/procedure. For example, for WTRU-assisted positioning or for WTRU-based positioning, the WTRU may be triggered to support LPP sessions/procedures for delayed mobile called location requests (MT-LR) or at delayed MT-LR.

Representative procedures for performing location services continuity with LPP may include any of the following:

(1) The WTRU may include information about supporting location service continuity (e.g., a requirement to support location measurement/reporting without interruption) in LPP messages or access layer (AS layer messages (e.g., RRC signaling), for example, the location capability information may be provided by the WTRU in LPP provide capability messages;

(2) The WTRU receives assistance information indicating, including, and/or including one or more PRS configurations/parameters (e.g., the WTRU may receive additional information associated with PRS configurations, including any of (i) validity conditions for use with one or more PRS configurations (e.g., area/cell IDs where PRS configurations are to be used), (ii) mobility conditions (e.g., speed and/or direction) that may or may need to be met for use with certain PRS configurations). The assistance information may be received in one or more messages, such as LPP assistance data transfer messages. The WTRU may receive assistance data/information, e.g., indicating and/or including a location mobility configuration including and/or including one or more rules/conditions. The one or more rules and/or conditions may indicate/include one or more of the following: (a) Timing information, (b) cell ID information and/or (3) RSRP thresholds, e.g., measured on PRS or non-positioning RS/channels, indicating when to release/stop PRS configuration associated with a source cell/gNB/base station and to begin using new PRS configuration associated with a target cell/gNB/base station during mobility. The WTRU may receive information indicating/including a reporting configuration. The reporting configuration may indicate information to be included when the WTRU sends a positioning report including a measurement report and/or a position estimate. For example, the reporting configuration may include/include any of the following: information about the cell ID to report, periodicity for sending a positioning report, and/or mobility information to report (e.g., WTRU speed, expected speed, direction, expected direction, environmental conditions, expected environmental conditions, indoor/outdoor status, expected indoor/outdoor status, etc.);

(3) The WTRU may use at least one PRS configuration upon or after receiving the request, which may satisfy an associated validity condition for performing measurements on the PRS, (ii) may not be provided to the WTRU in LPP assistance data, and/or (iii) may not be provided to the WTRU via a POSIB, e.g., when the WTRU is connected to a source base station/gNB, e.g., when a HO (e.g., for a data link HO) to a target base station/gNB (which may be associated with a different PRS configuration) is experienced or during the HO), the WTRU may use the PRS configuration associated with the target gNB when the WTRU determines that the configuration associated with the target gNB is not available (e.g., because the PRS configuration (i) is not pre-configured in the WTRU, (ii) may not be provided to the WTRU via a POSIB entity, (iii) may indicate that the WTRU may be able to the WTRU via a PRS, e.g., a new PRS entity, (i) may be provided to the WTRU via a PRS, and/or the WTRU may indicate that the current configuration (i) may be provided to the target base station/gNB via a network, e.g., the POSIB may indicate that the current configuration may be provided to the target base station/gNB via the network, the current configuration may be indicated, the WTRU may be indicated to the WTRU, and the target configuration may be indicated to the WTRU, e.g., the target configuration may be indicated via the network, and the target configuration may be indicated, A network entity, LMF, and/or gNB, etc.) sends information or an indication indicating a change in PRS configuration from a PRS configuration associated with a source base station/gNB to a PRS configuration associated with a target base station/gNB. For example, the WTRU may send information or an indication in an LPP message (e.g., an LPP provide location information message, and/or an LPP provide/request assistance information message, etc.) and/or an access layer (AS) layer message (e.g., via RRC signaling, medium Access Control (MAC) Control Element (CE), and/or Uplink Control Information (UCI));

(4) The WTRU performs PRS measurements using appropriate PRS configurations before, during, and/or after HO (e.g., when supporting WTRU-assisted positioning, the WTRU may send measurement reports to a network (e.g., base station, network entity, LMF, and/or serving gNB, etc.). The WTRU may send measurements to the LMF via the LPP provide location information message and may include or indicate information about the WTRU's mobility (e.g., time instance when HO command is received, time instance when HO complete message is sent, and/or time instance when changing to a different PRS configuration during mobility, etc.). When supporting WTRU-based positioning, the WTRU may determine its location estimate based on PRS measurements. When supporting MT-LR and/or delayed MT-LR, the WTRU may send a location estimate to the LMF, e.g., via a provide location information message, and may include information regarding WTRU mobility. For example, when supporting mobile originated location request (MO-LR), the WTRU may send a location estimate to an application/location services (LCS) client/application.

The content of the request for the new PRS configuration sent by the WTRU may include various types of information. For example, the request may include information about the target TRP/gNB, such as a cell ID. Alternatively or additionally, the request may include information about the measurement of the target/neighboring TRP/gNB, such as RSRP measured on RRM measurements (e.g., SSB, CSI-RS) and PRS measurements. Alternatively or additionally, the request may include information about the PRS configuration, such as a flag and/or identifier indicating an existing/new PRS configuration. Alternatively or additionally, the request may include information about mobility, such as a mobility report containing a mobility path (e.g., a list of one or more cell IDs and/or WTRU coordinates traversed by the WTRU over a duration) and/or WTRU mobility attributes (e.g., WTRU speed, direction, distance traveled in a direct/straight path).

The WTRU may send a request for a new PRS configuration and/or update/change an existing PRS configuration in various ways. For example, the WTRU may send the request in the NAS message using at least one of the LPP procedures for sending a request for assistance information and/or configuration updates to the LMF. Alternatively, the WTRU may include the request in location information sent to the network, the location information including a location measurement report and/or location information. In another alternative, the WTRU may send the request in a location mobility report, which may contain information about mobility. Alternatively or additionally, the WTRU may send the request using RRC signaling, such as by sending a request for a new PRS configuration to a TRP/gNB in the RAN, where the TRP/gNB may be associated with a serving/source or target cell. Alternatively or additionally, the WTRU may send the request using layer 2/layer 1 (L2/L1) signaling, such as by sending the request to the serving gNB in a MAC Control Element (CE) or Uplink Control Information (UCI).

In one solution, a WTRU may be configured by a network having a location service continuity configuration that may include one or more location service continuity conditions and/or a configuration for supporting at least one location service continuity mode. In this case, both the location service continuity condition and the location service continuity mode may be configured in the WTRU by the LMF or the RAN (e.g., the serving gNB via RRC). Alternatively, the location service continuity condition may be configured by the LMF and the location continuity mode may be configured by the RAN, for example.

By using location service continuity configuration, support for service continuity and/or mobility may be achieved for WTRU-based location and WTRU-assisted location support. In the case of WTRU-based positioning, the WTRU may receive appropriate assistance information/configuration updates and PRS configuration based on WTRU mobility and in a timely manner (e.g., before/during data link HO) so that the WTRU can perform PRS measurements and determine its location information. Also, with respect to WTRU-assisted positioning, the WTRU may use PRS configuration received during mobility to make PRS measurements and send measurement reports via the serving gNB. For example, in both WTRU-based positioning and WTRU-assisted positioning, the new PRS configuration may be composed of one or more TRPs/gnbs that may use PRSs similar to the target TRP/gNB of the data link HO to which the WTRU experiences. In addition, location mobility may also be supported for mobile originated location request (MO-LR) and mobile called location request (MT-LR) procedures associated with WTRU-based and WTRU-assisted location, for example.

The location service continuity conditions configured in and/or monitored by the WTRU may include the WTRU sending a request for a new PRS configuration to the network (e.g., LMF and/or RAN entity and/or base station) or a requirement to update/change an existing PRS configuration when triggered by one or more conditions. For example, the conditions that may trigger the transmission of the request may include the unavailability of a suitable PRS configuration. For example, the WTRU may send a request when determining that one or more target/neighbor cells (e.g., cell IDs), which may be detected by the WTRU from SIB/SSBs received from the target/neighbor cells, are not currently available at the WTRU, within the assistance information/configuration and/or existing PRS configuration. Also, when the WTRU is able or may receive at least a portion of PRSs from the target cell and does not have an associated PRS configuration, the WTRU may send a request for a new PRS configuration.

Another condition that may trigger the transmission of the request may include one or more RRM measurement thresholds. For example, the WTRU may request a new PRS configuration when RRM measurements (e.g., SSB, RSRP of CSI-RS) associated with the target/neighbor cell are above a configured threshold and/or remain above the threshold for the duration of a particular configuration. For example, the threshold for sending a request for a new PRS configuration based on RRM measurements may be below/above the threshold for conventional data link HO configuration. In another example, the thresholds for location service continuity and data link HO may be the same. In this case, for example, the WTRU may include the location service continuity flag/indication in an RRM measurement report that is sent to the serving gNB for the data link HO. For example, when performing the HO procedure, the serving gNB may forward the request for the new PRS configuration to the LMF (e.g., via new radio positioning protocol a (NRPPa)) or to the target gNB (e.g., via Xn).

Another condition that may trigger the transmission of the request may include a timer associated with the existing PRS configuration. For example, the WTRU may send a request when a validity timer associated with one or more existing PRS configurations expires.

Another condition that may trigger the sending of the request may include an indication from the network/higher layer. For example, the WTRU may send a request for a new PRS configuration when an indication to release an existing PRS configuration and/or a measurement gap configuration for PRS measurements is received from a serving gNB. Also, the WTRU may send a request (e.g., MO-LR) when triggered by an application/location services (LCS) client in the WTRU.

Another condition that may trigger the transmission of the request may include a change in the WTRU radio environment or WTRU properties. For example, the WTRU may send a request for a new PRS configuration when certain attributes in the WTRU radio environment are detected, including interference and/or multipath (e.g., measurements above/below a threshold).

Another condition that may trigger the transmission of the request may include a change in WTRU properties. For example, when a change in WTRU attributes is detected, the WTRU may send a request for a new PRS configuration. Examples of WTRU attributes include an increase/decrease in WTRU rate in a particular direction (e.g., away from the coverage area of one or more TRP/gnbs using existing PRS configurations). Another example of WTRU attributes includes a change in WTRU orientation (e.g., in a direction opposite to the direction in which the beam associated with the existing PRS configuration was received). Another example of WTRU attributes includes a change in distance traveled by the WTRU by a distance threshold (e.g., along a straight/direct path). The WTRU may send the request in response to one or more of these or other conditions being met.

Another condition that may trigger the transmission of the request may include a data link HO trigger. For example, the WTRU may send a request for a new PRS when triggered by one or more conditions/signaling associated with a data link HO procedure. Exemplary data link HO triggers include transmission of RRM measurement reports and/or reception of Radio Resource Control (RRC) reconfiguration messages (including HO commands) from the serving gNB, transmission of connection setup messages (e.g., random access control channel (RACH), RRC signaling) to the target gNB, etc.

In one example, the WTRU may be configured to send location information (e.g., measurement reports for WTRU-assisted location and/or location information for WTRU-based location) to the LMF when triggered by one or more of the location service continuity conditions described above. The WTRU may send positioning information via the serving gNB before/during the data link HO. In this case, the LMF may determine a supply of new PRS configurations based on positioning information sent by the WTRU and may send assistance information/configuration updates to the WTRU including the new/updated PRS configurations when the new PRS configurations are configured at one or more target TRP/gnbs. In one example, the location information sent by the WTRU may include a location service continuity report based on the trigger condition.

In another example, one or more PRS configurations may be pre-configured in the WTRU, possibly along with a mapping between location service continuity conditions and associated PRS configurations. Different PRS pre-configurations may also be associated with one or more groups of TRP/gNB (e.g., IDs of TRP/gNB). In this case, the WTRU may select a new PRS configuration from the pre-configured list and/or release an existing PRS configuration when one or more location service continuity conditions are detected. For example, the selected new PRS configuration may then be used to request an associated measurement gap configuration and/or perform PRS measurements.

In addition, the location service continuity configuration received by the WTRU may also include various location service continuity modes. For example, the location services continuity pattern included in the configuration may indicate the use of a new PRS configuration of the target gNB while in the coverage area of the source gNB prior to the data link HO. Alternatively or additionally, the location service continuity pattern included in the configuration may indicate use of an existing PRS configuration of the source gNB while in a coverage area of the target gNB after the data link HO. Alternatively or additionally, the positioning service continuity pattern included in the configuration may indicate the use of two PRS configurations of the source and target gnbs during the data link HO.

The WTRU may use one or more of the location service continuity modes based on an indication received from the network (e.g., the same or different indication containing a new PRS configuration) or autonomously determined by the WTRU based on triggers similar to the location service continuity conditions described above.

The WTRU may receive one or more RAN configurations (e.g., RAN configuration information) associated with a location to be applied during mobility. For example, the WTRU may receive RAN configurations (e.g., RAN configuration information) from a serving gcb (e.g., source base station/gcb) or a target base station/gcb, which may be applied by the WTRU before, during, and/or after the HO while continuing to support the positioning procedure. The RAN configurations described herein may include any of the following attributes/parameters/information and may be applied to the various embodiments disclosed herein:

(1) One or more Measurement Gap (MG) configurations (e.g., when using a first PRS configuration associated with a source base station/gNB/cell (e.g., before and/or during HO), a WTRU may be configured with a first MG configuration, and/or when using a second PRS configuration associated with a target base station/gNB/cell (e.g., during and/or after HO), a WTRU may be configured with a second MG configuration);

(2) One or more Configuration Grant (CG) configurations (e.g., for the purpose of sending measurements, reports, and/or position estimates in a photo-associated PRS measurement and/or reporting configuration), a WTRU may be configured with a first CG configuration when associated with a source gNB/cell (e.g., before and/or during HO) and a second CG configuration when associated with a target gNB/cell (e.g., during and/or after HO). In another example, a WTRU configured with CG configuration by a source gNB/cell may continue to use the same or updated CG configuration during or while experiencing HO when an indication is received from the source or target gNB/cell indicating that the WTRU may be permitted to use the CG configuration; and/or

(3) A Timing Advance (TA) configuration (e.g., to support UL-based positioning), a WTRU may be configured with a first TA configuration including a TA timer (TAT) (e.g., timer parameters/information) when using a first SRSp configuration associated with a source gNB/cell (e.g., before and/or during HO), and a second TA configuration when using a second SRSp configuration associated with a target gNB/cell (e.g., during and/or after HO). For example, the WTRU may use the first SRSp configuration if or as long as the TAT associated with the first TA configuration is valid (e.g., the condition of the TA configuration is valid and/or the time interval associated with the TAT has not expired), and the WTRU may use the second SRSp configuration if or as long as the TAT associated with the second TA configuration is valid (e.g., the condition of the TA configuration is valid and/or the time interval associated with the TAT has not expired). For example, the first and second TA configurations may be received by the WTRU from the source gNB/cell and/or from the target gNB/cell.

In some examples, the TA configuration (e.g., using TAT) may be associated with CG configuration and/or PRS configuration. The WTRU may use one or more TA configurations provided by the source/target gNB/cell when determining/deciding which of the one or more CG configurations to use during mobility and/or when performing positioning measurements/reporting. For example, the WTRU may use the first CG configuration if or as long as the TAT associated with the first TA configuration is valid, and the WTRU may use the second CG configuration if or as long as the TAT associated with the second TA configuration is valid, and so on.

In some cases, the WTRU may send a request to the serving gNB for a new PRS configuration to support positioning mobility. For example, where LMF functionality may be supported in the RAN, the WTRU may send a request to support location service continuity (e.g., a request for a new PRS configuration) to the serving gNB based on detection of one or more configured location service continuity conditions.

The WTRU may send a request for location service continuity in RRC signaling, UL MAC CE, and/or UCI before or during the data link HO. The serving gNB may then send a request to the LMF and/or directly to the target cell/gNB for a new PRS configuration associated with one or more target cells/gNB. The LMF or target cell/gNB may forward the associated PRS configuration to the serving gNB for supporting positioning mobility/service continuity. The WTRU may receive a new PRS configuration and/or an indication to use/activate a (new) PRS (pre) configuration from a serving gNB via RRC signaling, DL MAC CE, and/or Downlink Control Information (DCI). The new PRS configuration may be received by the WTRU in an RRC reconfiguration message (e.g., with a HO command) or in a different message before/during the data link HO. The WTRU may then perform measurements of DL-PRS using the received/activated new PRS configuration and send measurement reports to the current serving gNB.

In some cases, the WTRU may receive new/updated PRS configurations when sending location services continuity reports. For example, the WTRU may receive a new/updated PRS configuration from a network (e.g., an LMF and/or RAN entity and/or base station) based on a location service continuity report sent by the WTRU. For example, the WTRU may indicate information related to the ID of the target/neighbor cell and/or RRM measurements associated with the target/neighbor cell in the location service continuity report, regardless of whether the target cell/gNB uses the same or different PRS configuration available at the WTRU. The WTRU may send information related to WTRU mobility attributes, such as speed, direction, and/or orientation, in a location service continuity report. In another example, the WTRU may send the mobility state indication to the network in an LPP measurement report or in a separate location mobility report. For example, the WTRU may send a location service continuity report when triggered by one or more of the above-described trigger conditions.

The location service continuity report may be sent via the serving gNB periodically or based on one or more conditions described above (e.g., when RSRP of the neighboring cell is above a threshold, when triggered by a data link HO). For example, as the WTRU speed increases, the WTRU may increase the periodicity of transmission for location services continuity reports to provide a more accurate assessment of the WTRU's location to the network. For example, when the WTRU experiences a data link HO, the WTRU may change from a first reporting periodicity to a second reporting periodicity, wherein the second periodicity may be higher than the first periodicity. In another example, the WTRU may be configured with a group consisting of one or more TRPs/gnbs associated with PRS configurations available at the WTRU. The WTRU may also be configured with a flag associated with one or more TRP/gnbs that instructs the WTRU to send a location service continuity report to the network when the WTRU detects a TRP/gNB ID with the flag.

In response to sending the positioning service continuity report, the WTRU may receive a new/updated PRS configuration, possibly along with information about when to start using the new PRS configuration and to stop/release using the existing PRS configuration. The new/updated PRS configuration may be received prior to and/or independent of the data link HO procedure. The reception may be based on a determination of WTRU position within a positioning region (e.g., a region associated with a TRP/gNB group in which an existing PRS configuration is applied and which may be used by the WTRU for positioning measurements). The reception may also be based on coordination between the TRP/gNB and the LMF. For example, when the WTRU experiences a HO to a different cell, the WTRU may periodically receive new/updated PRS configurations.

Resources (including at least location service continuity reports and/or measurement reports) for transmitting location information to the network may be received by the WTRU from the serving gNB. These resources may be received as dynamic grants or configuration grants based on resource requests sent by the WTRU (e.g., scheduling Request (SR)/Buffer Status Report (BSR) or RRC assistance information). In one example, the WTRU may send a request for configuration authorization to the serving cell for sending location information. The WTRU may also indicate the use of configuration grants during/after the HO for transmitting positioning information including measurements made during the HO. In this case, the serving gNB may transmit a context associated with the configuration grant to the target gNB and indicate to the WTRU certain conditions for using the configuration grant. For example, upon HO to the target gNB, the WTRU may use the same configuration grant for at least the initial transmission and/or possibly for a certain validity duration.

In another solution, the LMF may receive an indication of the WTRU mobility state from the RAN when the WTRU experiences a data link HO to the target cell (where the target cell may be within an existing PRS configuration available at the WTRU). Based on the mobility state, the LMF may send an update to the WTRU including the updated PRS configuration. In this case, the updated PRS configuration may contain information about one or more new TRP/gnbs that the WTRU may use for PRS measurements.

For example, the updated PRS configuration received by the WTRU may also include information related to TRP/gNB that is of higher importance/priority for the WTRU to make PRS measurements and to increase positioning accuracy. In one example, when the WTRU experiences a HO from the source cell to the target cell, the importance of the source cell in the updated PRS configuration switches from a higher value to a lower value because the previous source cell becomes the neighbor cell after the HO.

The updated PRS configuration may be received by the WTRU periodically or based on a mobility state. For example, updated PRS configurations may be received more frequently with higher periodicity when the WTRU moves at a higher speed or the rate of HO to one or more target cells is higher.

In some cases, the WTRU uses PRS configuration of the target gNB prior to HO in the coverage area of the source gNB. For example, a WTRU configured with a new PRS configuration associated with a target TRP/gNB may use the new PRS configuration while still connected with the source TRP/gNB over the data/RRC link. In this case, the new PRS configuration of the target TRP/gNB may be used by the WTRU to perform positioning measurements while in the coverage area of the source TRP/gNB prior to the data link HO. When using the new PRS configuration, the WTRU may expand, release, and/or suspend the existing PRS configuration, e.g., possibly when the WTRU is within coverage of the source TRP/gNB.

The WTRU may begin using the new PRS configuration based on various PRS usage trigger factors configured in the WTRU. An exemplary trigger for starting to use a new PRS configuration may include receipt of a new PRS configuration. In this example, the WTRU may use the new PRS configuration immediately or for a duration of a certain configuration. In this case, for example, the WTRU may start a timer upon reception and use the new PRS configuration when the timer expires.

Another exemplary trigger for starting to use the new PRS configuration may include RRM/PRS measurements of the target cell. For example, the WTRU may use the new PRS configuration when the RSRP of the SSB and/or neighbor cell RS is above a threshold and/or remains above the threshold for the duration of the configuration. Also, the WTRU may begin using the new PRS configuration when the RSRP measurement of the PRS received from the target cell is above a threshold.

Another exemplary trigger for starting to use the new PRS configuration may include target cell ID detection. For example, the WTRU may use the new configuration when the target cell ID is detected in the SIB/SSB received from the target cell.

Another example trigger for starting to use a new PRS configuration may include receiving an indication from a network. For example, the WTRU may begin using the new PRS configuration upon receiving the indication from the LMF (e.g., in an LPP location request) or the RAN (e.g., in a MAC CE or DCI).

Another exemplary trigger for starting to use a new PRS configuration may include a priority. For example, the new PRS configuration may be used when a priority associated with the new PRS configuration is higher than or equal to an existing PRS configuration or other data transmission/reception.

Another exemplary trigger for starting to use a new PRS configuration may include data/signaling transmission. For example, the WTRU may begin using the new PRS configuration when data/signaling transmission/reception is completed over a dedicated resource bearer/signaling resource bearer (DRB/SRB). Alternatively or additionally, the WTRU may begin using the new PRS configuration upon determining that there is no buffered or pending data/signaling transmission/reception in a subsequently configured duration/slot.

Another exemplary trigger for initiating use of a new PRS configuration may include a data link HO trigger. For example, the WTRU may use the new PRS configuration before or after transmission of RRM measurement reports containing neighbor cell measurements (possibly for triggering a data link HO). Alternatively, the WTRU may begin using the new PRS configuration upon receipt of a HO command, which may contain an explicit or implicit indication to begin using the new PRS configuration.

Another exemplary trigger for starting to use a new PRS configuration may include alignment with a measurement gap configuration. For example, the WTRU may use the new PRS configuration when sending a request for a measurement gap (e.g., in RRC) or receiving a measurement gap configuration associated with the new PRS configuration of the target TRP/gNB/cell. In this case, the request and/or response to the measurement gap configuration may be performed by the WTRU via the serving TRP/gNB.

When using the new PRS configuration, the WTRU may extend, stop and/or release the existing PRS configuration, or continue to use the new and existing PRS configurations with at least an overlap of one or more time/frequency resources for PRS. Possible combinations of new and existing PRS configuration uses may be received by the WTRU in assistance information/configuration updates from the network or determined by the WTRU. For example, the WTRU may determine a new PRS configuration with use of existing PRS configurations with at least one or more overlaps of time/frequency resources between the configurations for improving positioning accuracy. In this case, the WTRU may use one or more combinations of PRS configurations when determining that the positioning accuracy achieved by measurements using the existing PRS configuration is below an accuracy threshold (e.g., due to interference or fluctuations in the WTRU radio environment).

Fig. 2 is a system diagram illustrating a WTRU receiving a Downlink (DL) Positioning Reference Signal (PRS) from a target TRP/gNB when connected to a source TRP/gNB, according to one embodiment.

Referring to fig. 2, a first coverage area 208 associated with a source TRP/gNB 202 may overlap with a second coverage area 206 associated with a target TRP/gNB 204. After the HO in the coverage area 206 of the target TRP/gNB204, the WTRU 200 may use the PRS configuration of the source TRP/gNB 202. For example, a WTRU 200 configured with a new PRS configuration associated with a target TRP/gNB204 may continue to use the existing PRS configuration associated with the source TRP/gNB 202 after performing a data link HO to the target TRP/gNB204 and/or establishing a data/RRC connection with the target TRP/gNB. In this case, the WTRU 200 may use the PRS configuration of the source TRP/gNB 202 to perform positioning measurements while in the coverage area 206 of the target TRP/gNB204 after the data link HO.

The WTRU 200 may release/update the existing PRS configuration associated with the source TRP/gNB 202 based on various trigger conditions configured in the WTRU 200. One exemplary trigger condition for releasing/updating an existing PRS configuration may include receipt of a new PRS configuration. For example, the WTRU 200 may release/update the existing PRS configuration upon receiving a new PRS configuration of the target TRP/gNB204 from the target TRP/gNB 204.

Another exemplary trigger condition for releasing/updating existing PRS configurations may include RRM/PRS measurements of the source cell. For example, the WTRU 200 may release/update the existing PRS configuration when the RSRP of the SSB and/or the source cell RS is below a threshold and/or remains below a threshold for the duration of the configuration. Also, the WTRU 200 may release/update the existing PRS configuration when the RSRP measurement of the PRS received from the source cell is below a threshold.

Another example trigger condition for releasing/updating an existing PRS configuration may include receiving an indication from a network. For example, the WTRU 200 may release/update the existing PRS configuration and begin using the new PRS configuration upon receiving the indication from the LMF (e.g., in an LPP location request) or the RAN (e.g., in a MAC CE or DCI).

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include expiration of a timer. For example, the WTRU 200 may release/update the existing PRS configuration for a specific duration during/at the time of performing a data link HO to a target cell. In this case, the WTRU 200 may start a timer upon receiving a HO command/RRC reconfiguration message from the source TRP/gNB 202 or upon sending a RACH/Radio Resource Control (RRC) message to the target TRP/gNB 204 for connection establishment. The WTRU 200 may then release/update the existing PRS configuration when the configured timer expires.

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include a priority. For example, an existing PRS configuration may be released/updated when a priority associated with the new PRS configuration is higher than or equal to an existing PRS configuration or other data transmission/reception.

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include data/signaling transmission. For example, the WTRU 200 may release/update the existing PRS configuration when data/signaling transmission/reception is completed through the DRB/SRB and/or it is determined that there is no buffered or pending data/signaling transmission/reception for the duration of the subsequent configuration when connected to the target TRP/gNB 204.

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include a data link HO trigger. For example, the WTRU 200 may release/update the existing PRS configuration before or after transmitting RRM measurement reports containing neighbor cell measurements for triggering a data link HO. Alternatively, the WTRU 200 may release/update the existing PRS configuration upon receipt of a HO command, which may contain an explicit or implicit indication to release the existing PRS configuration.

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include alignment with a measurement gap configuration. For example, the WTRU 200 may release/update the existing PRS configuration when a request for a measurement gap is sent (e.g., in RRC) or a measurement gap configuration associated with a new PRS configuration of the target TRP/gNB/cell is received. In this case, for example, the request and/or response to the measurement gap configuration may be performed by the WTRU 200 via the target TRP/gNB 204.

Another exemplary trigger condition for releasing/updating an existing PRS configuration may include a reply/fail condition. For example, after receiving the new PRS configuration, the WTRU 200 may revert to using the existing PRS configuration without release when the new PRS configuration fails to meet certain positioning accuracy conditions (e.g., RSRP of PRS measured below a threshold) or due to other failure conditions of the new PRS configuration. For example, the WTRU 200 may also revert to the existing PRS configuration when it cannot receive the measurement gap configuration associated with the PRS configuration of the target TRP/gNB 204.

Upon releasing/updating the existing PRS configuration, the WTRU 200 may begin to perform positioning measurements in the coverage area 206 of the target TRP/gNB 204 using the new PRS configuration. For example, the WTRU 200 may use the new PRS configuration when transmitting and/or receiving a measurement gap configuration associated/aligned with the new PRS configuration of the target TRP/gNB 204.

In examples where both the source TRP/gNB 202 and the target TRP/gNB 204 use the same PRS configuration, the WTRU 200 may continue to use the existing PRS configuration after HO without releasing or updating the configuration. In this case, the WTRU 200 may receive an indication (e.g., in a HO command) from the source TRP/gNB 202, possibly suspending measurements using the existing measurement gap configuration during the HO and/or resuming measurements using the same measurement gap configuration after the HO. In this case, the WTRU 200 may indicate the use of the existing measurement gap configuration to the target TRP/gNB 204 explicitly (e.g., in RACH messages, RRC signaling, MAC CE, and/or UCI) or implicitly by resuming measurements made using the existing measurement gap configuration when performing the HO.

Fig. 3 is a system diagram illustrating a WTRU receiving DL-PRS from a source gNB when connected to a target gNB.

Referring to fig. 3, a first coverage area 308 associated with a source TRP/gNB 302 may overlap with a second coverage area 306 associated with a target TRP/gNB 204. The WTRU 300 may use a PRS configuration of the source TRP/gNB 302 and a PRS configuration of the target TRP/gNB 304 during a data link HO. For example, a WTRU 300 configured with a new PRS configuration associated with the target TRP/gNB 304 and an existing PRS configuration associated with the source TRP/gNB 302 may use both PRS configurations during a data link HO. For example, the use of these two PRS configurations may be intended for increasing positioning measurement accuracy and reliability.

In this case, the WTRU 300 may perform positioning measurements based on PRSs received from the source TRP/gNB 302 and the target TRP/gNB 304 using both PRS configurations. To use both PRS configurations, the WTRU 300 may begin using the new PRS configuration while continuing to use the existing PRS configuration prior to HO. In this case, for example, the WTRU 300 may send a request to the serving gNB to extend/change the existing measurement gap configuration such that the updated measurement gap configuration spans both the existing PRS configuration and the new PRS configuration.

For example, to support one or more signaling/functions associated with a data link HO, the WTRU 300 may suspend measurements using the extended measurement gap configuration for a duration during the HO. For example, upon completion of the HO, the WTRU 300 may resume making measurements using the extended measurement gap configuration until a condition for releasing/updating the PRS configuration of the source TRP/gNB 302 is met (e.g., the RSRP of the PRS falls below a threshold). In this case, after releasing/updating the PRS configuration of the source TRP/gNB 302, the WTRU 300 may revert to a new PRS configuration using the target TRP/gNB 304, possibly along with an associated reduced/updated measurement gap configuration. The WTRU 300 may transition from using the extended measurement gap configuration to the reduced/updated measurement gap configuration based on sending an explicit request to the target gNB to change the measurement gap configuration or by implicitly using the measurement gap configuration aligned with the new PRS configuration.

Fig. 4 is a system diagram illustrating a WTRU receiving DL-PRS from a source gNB and a target gNB during a HO according to one embodiment.

Referring to fig. 4, a first coverage area 408 associated with a source TRP/gNB 402 may overlap with a second coverage area 406 associated with a target TRP/gNB 404. The WTRU 400 may determine the use of PRS configurations based on the measurement gap configuration. For example, in implementations where measurement gap configuration is applied to perform PRS measurements, the WTRU 400 may send a request to the serving gNB to request configuration/configuration information for measurement gaps associated with new PRS configurations of one or more target gnbs/cells. In this case, upon receiving the new PRS configuration, a request for configuration of measurement gaps may be sent in RRC signaling, MAC CE, and/or UCI. For example, the determination of the size/length (e.g., in the time and/or frequency domain) of the measurement gap configuration may be based on the new and/or existing PRS configuration. For example, when the WTRU 400 is configured with a suitable and efficient measurement gap configuration, the WTRU 400 may use an existing or new PRS configuration to perform positioning measurements.

In one example, a WTRU 400 that may be configured with a measurement gap configuration for performing measurements using an existing PRS configuration may suspend measurements using the measurement gap configuration according to a new PRS configuration. In this case, the WTRU may perform various operations. For example, the WTRU 400 may perform operations that require suspension/release of measurement gap configurations associated with existing PRS configurations. In this case, the WTRU 400 may be configured by the network with rules for determining how/when to suspend/release the existing measurement gap configuration. Hereinafter, suspending/releasing the measurement gap configuration may refer to the WTRU 400 suspending/stopping PRS measurements using the measurement gap configuration. In one example, suspending/releasing the measurement gap configuration may correspond to updating the measurement gap configuration. For example, the WTRU 400 may suspend/release the measurement gap configuration when one or more conditions associated with using PRS configuration are met. For example, the WTRU 400 may send a request for a new measurement gap configuration to the network while suspending/releasing the existing measurement gap configuration. For example, when the WTRU 400 pauses the existing measurement gap configuration without releasing, the WTRU 400 may return to using the measurement gap configuration for PRS measurements when a request for a new measurement gap is sent.

Another operation that may be performed by the WTRU 400 may require dynamically updating the measurement gap. For example, the WTRU 400 may dynamically update the measurement gap configuration upon receiving a new PRS configuration and/or determining an updated measurement gap configuration. In this case, the updated measurement gap configuration may be a new measurement gap configuration that may not contain any overlapping time/frequency resources that overlap with the time/frequency resources of the previously configured measurement gap. For example, the WTRU 400 may determine a new measurement gap configuration based on the received new PRS configuration. Alternatively, the updated measurement gap configuration may contain one or more overlapping time/frequency resources or extend an existing measurement gap configuration. The WTRU 400 may send an indication to the network indicating an updated measurement gap configuration (e.g., an incremental change from an existing measurement gap configuration).

In one example, a request to suspend/release/update an existing measurement gap configuration may be explicitly sent in the same request to configure a new measurement gap configuration. In this case, the response received by the WTRU 400 may include commands to suspend/release/update the existing measurement gap and configure the new measurement gap. In another example, the request to suspend/release the existing measurement gap is implicitly indicated via a request for a new measurement gap configuration. Alternatively, the request and response for suspending/releasing/updating the existing measurement gap configuration and the new measurement gap configuration may be performed via separate signaling.

In another example, the WTRU 400 may begin using the new measurement gap configuration upon receiving a response from the network (e.g., the source TRP/gNB 402 or the target TRP/gNB 404) containing information about the measurement gap configuration (e.g., time/frequency resources associated with the measurement or the ID of the measurement gap). The WTRU 400 may cease using the existing measurement gap configuration after sending the request or upon receiving a new measurement gap configuration from the network. Alternatively, the WTRU 400 may cease using the existing measurement gap configuration upon expiration of a configured timer, which may be set after sending the request or receiving a network response containing the new measurement gap configuration.

In another example, a WTRU 400 configured with a measurement gap configuration associated with the PRS configuration of a target TRP/gNB 404 may perform measurements of PRSs received from the target TRP/gNB 404 when the WTRU 400 is under the coverage of the source TRP/gNB 402. In another example, when the WTRU 400 is under the coverage of the target TRP/gNB 404, the WTRU 400 may use a measurement gap configuration associated with the existing PRS configuration of the source TRP/gNB 402 to measure PRSs received from the source TRP/gNB 402 after HO.

In another example, the WTRU 400 may suspend/release measurement gap configurations, including measurement gaps associated with existing and/or new PRS configurations, to ensure that signaling/functionality associated with the data link HO may be supported during the HO. In this case, the data link HO signaling/functions may include transmission of RRM measurement reports, reception of RRC reconfiguration messages/HO commands, reception of synchronization signals (e.g., primary Synchronization Signals (PSS), secondary Synchronization Signals (SSS)) from the target cell, and/or transmission of connection setup messages (e.g., RACH/RRC signaling). In one example, the WTRU 400 may suspend measurement gap configuration and measure PRSs received from the target cell to support HO signaling/functions during HO when configured with measurement gaps associated with the new PRS configuration. In another example, the WTRU 400 may suspend/release the measurement gap configuration associated with the existing PRS configuration and make measurements on PRSs received from the source cell to support signaling/functionality during HO. Upon completion of the HO signaling, the WTRU 400 may then resume the suspended measurement gap configuration to perform PRS measurements. The WTRU 400 may continue to use the measurement gap configuration after HO until one or more release conditions associated with releasing the measurement gap configuration (e.g., a trigger for using a new PRS configuration, expiration of a timer, and/or network indication) are met.

In another example, the WTRU 400 may be configured with one or more priority rules for using measurement gap configuration when the configuration overlaps with signaling/functionality associated with HO. For example, when the WTRU 400 sends RRM measurement reports to the serving gNB in RRC signaling, the priority rule may indicate to suspend/release the measurement gap configuration associated with the positioning measurement, possibly because the priority assigned to RRC signaling is higher than the priority assigned to positioning measurement. For example, when a higher priority is assigned for positioning measurements, the WTRU 400 may resume positioning measurements using configured measurement gaps upon sending RRC signaling or after receiving an RRC reconfiguration message containing HO commands from the serving gNB. In this case, for example, different HO-related signaling/functions may be associated with different priority values, and the WTRU 400 may support one or more signaling/functions, including priority order based positioning measurements and reporting.

In another example, when the WTRU 400 is triggered by one or more data link signaling/functions associated with the HO, a priority rule configured in the WTRU 400 may indicate that the WTRU 400 should not suspend/release the measurement gap configuration associated with the positioning measurement. In this case, for example, when signaling/functionality associated with the data link HO is performed on an active bandwidth portion (BWP), which may/may not overlap with the bandwidth/resources associated with PRS measurements, the WTRU 400 may continue to perform PRS measurements using the configured measurement gap configuration while continuing to transmit/receive HO-related signaling during the HO. For example, upon completion of the HO procedure (e.g., WTRU 400 establishes a connection with target TRP/gNB 404), WTRU 400 may revert to performing (e.g., performing only) PRS measurements using the configured measurement gap configuration. In this example, for example, the rule for performing PRS measurements or transmission/reception of data/signaling on active BWP may be skipped in order to ensure that positioning accuracy is maintained, and also in order to avoid any positioning gaps.

To reduce the delay associated with the signaling/procedure for configuring the measurement gap configuration, the WTRU 400 may be preconfigured with one or more measurement gap configurations by the source gNB. The measurement gap pre-configuration may be associated with existing and/or new PRS configurations. By sending an indication (e.g., an identifier) related to the measurement gap to the target TRP/gNB 404 in a RACH message and/or RRC signaling, the WTRU 400 may trigger activation of a preconfigured measurement gap during HO. In this case, the WTRU 400 may be configured with one or more RACH resources/preambles by the serving gNB for different measurement gap pre-configurations. During/upon HO to the target TRP/gNB 404, the WTRU 400 may determine a measurement gap configuration to be used at the target TRP/gNB 404. For example, when the WTRU 400 may use a new PRS configuration associated with the target TRP/gNB 404 after HO, the WTRU 400 may send a RACH message to the target TRP/gNB 404 using RACH resources/preambles corresponding to the new measurement gap configuration. In this case, the transmission of the corresponding RACH message by WTRU 400 would indicate to the network to begin using the new PRS configuration and indicate the associated measurement gap configuration at target TRP/gNB 404. In another example, where the WTRU 400 uses an existing PRS configuration associated with the source TRP/gNB 402, the WTRU 400 may send RACH messages to the target TRP/gNB 404 using RACH resources/preambles corresponding to the existing/previous measurement gap configuration. The transmission of the corresponding RACH message by WTRU 400 will indicate the use of the existing PRS configuration and the associated measurement gap configuration after HO to the target TRP/gNB 404.

In another example, where the WTRU 400 uses a new PRS configuration associated with the target TRP/gNB 404 prior to HO, context associated with a measurement gap configuration aligned with the new PRS configuration may be transferred from the target TRP/gNB 404 to the source TRP/gNB 402 (e.g., via an Xn interface). In this case, WTRU 400 may receive an indication from source TRP/gNB 402 that may indicate an identifier of the configured measurement gap configuration so that WTRU 400 may use the new PRS configuration with the measurement gap configuration prior to HO.

In another example, where the WTRU 400 may continue to use the existing PRS configuration associated with the source TRP/gNB 402 after a HO to the target TRP/gNB 404, context associated with measurement gap configurations aligned with the existing/previous PRS configuration prior to the HO may be transferred from the source TRP/gNB 402 to the target TRP/gNB 404 (e.g., via an Xn interface). In this case, the WTRU 400 may send an indication (e.g., in RRC signaling, RACH, MAC CE, and/or UCI) to the target TRP/gNB 404 at HO, which may contain an identifier of the configured measurement gap configuration so that the WTRU 400 may use the existing PRS configuration with the measurement gap after HO.

In various implementations (including those described above with reference to fig. 2-4), the WTRU may send information about the positioning measurements to the serving gNB/cell in the RAN to assist the data link HO. For example, the WTRU may assist the RAN in performing a conventional data link HO based on the location measurement. In this case, a WTRU that may receive PRSs from one or more target/neighbor cells may send positioning information for a measurement report containing PRS measurements to a serving gNB. For example, the additional information that the WTRU may include in the measurement report for the auxiliary RAN may include a change in distance between the WTRU determined based on PRS measurements and the target/neighboring TRP/gNB that may be within a certain duration. The serving gNB may use PRS measurement reports and/or range change information reported by the WTRU to determine at least one target TRP/gNB to which the WTRU may potentially perform a data link HO.

The positioning information sent by the WTRU may also be used by the RAN to assist in the conditional HO procedure. In this case, one or more candidate target gnbs for the HO may be selected, e.g., based on positioning information sent by the WTRU. The serving gNB may then also provide certain conditions (e.g., one or more thresholds associated with the RSRP of PRS and/or RRM measurements) to the WTRU for evaluation before determining a target gNB for performing the data link HO. Alternatively, the WTRU may send an early request for a data link HO to the target cell to the serving cell based on PRS measurements and/or distance measurements. For example, a request sent by the WTRU may trigger a HO preparation procedure between the serving gNB and the indicated target gNB.

The WTRU may use the validity condition to determine PRS configurations to apply during mobility. In some examples, the WTRU may use validity conditions associated with one or more PRS configurations to determine when to start and/or stop using PRS configurations associated with the source base station/gNB/cell and the target base station/gNB/cell during mobility. For example, the validity conditions may be received by the WTRU from a network (e.g., network entity, base station, LMF, and/or gNB, etc.) in (i) one or more LPP messages (e.g., LPP provide assistance data messages, (ii) LPP request location information messages, etc., (iii) location service request messages (e.g., for MT-LR, delayed MT-LR, and/or MO-LR), and/or (iv) AS layer messages (e.g., via RRC signaling, MAC CE, and/or DCI):

(1) PRS configuration may effectively use one or more region validity conditions (e.g., region validity information) (e.g., cell ID, RAN notification Region (RNA), and/or CN region). In some examples, the WTRU may be configured with a first set of PRS configurations to be used by the WTRU when in a first validity area (e.g., under coverage of a first set of cells/gnbs/base stations) and a second set of PRS configurations to be used by the WTRU when in a second validity area (e.g., under coverage of a second set of cells/gnbs/base stations);

(2) PRS configuration may effectively use one or more time validity conditions (e.g., time validity information) (e.g., duration from a start time to an expiration time). For example, the WTRU may start a timer (apply expiration period) upon receiving an indication to begin using PRS configuration (e.g., via LPP location request and/or HO command), and may use the configuration to make PRS measurements if the timer/expiration period is valid for the duration of the configuration and/or does not expire;

(3) One or more mobility conditions of the WTRU (e.g., mobility information (e.g., the WTRU may be configured using one or more PRSs when (i) the WTRU speed is below/above a configured speed threshold, and/or (ii) the amount and/or rate of movement/orientation of the WTRU is increased/decreased by a threshold);

(4) One or more radio environment conditions of the WTRU (e.g., radio environment information (e.g., the WTRU may change from a first set of one or more PRS configurations to a second set when (i) measured RSRP on PRS or non-positioning RS/channels (e.g., CSI-RS, SSB) associated with the first set is above/below an RSRP threshold, (ii) a number of detected multipaths is above/below a threshold, and/or (iii) a non-line-of-sight (NLOS) condition is detected, etc.);

(5) The RRC state condition of the WTRU (e.g., whether the WTRU is in CONNECTED state, INACTIVE state, or IDLE state) (e.g., when operating in a different RRC state before, during, and/or after HO, the WTRU may change from using a first set of one or more PRS configurations to a second set). As an example, the WTRU may use a first set of PRS configurations when operating in an RRC CONNECTED state, may use a second set of PRS configurations when operating in a RRC INACTIVE state, and/or may use a third set of PRS configurations when operating in an RRC IDLE state. For example, the first, second, and third groups associated with different RRC states may include or include a subset of PRS configurations, which may be common across all groups. Alternatively, PRS configurations may be mutually exclusive across different groups associated with different RRC states.

When the WTRU determines that one or more PRS configurations are no longer valid (e.g., one or more validity conditions indicate that one or more PRS configurations are due) or are not met, the WTRU may perform any of the following:

(1) To the network (e.g., the WTRU may send information or an indication to the network indicating the PRS configuration identifier/ID and/or an expiration status of the configuration). The WTRU may indicate to update the PRS configuration and/or update one or more validity conditions associated with the indicated PRS configuration. For example, the information or indication sent to the network may be sent in or AS LPP messages, PRS on demand messages (e.g., to network entities, base stations, LMFs, and/or gnbs, etc.), and/or AS layer messages (e.g., via RRC, MAC CE, and/or UCI, etc.);

(2) Changing to an alternative valid PRS/SRSp configuration (e.g., when a first PRS configuration is determined to be no longer valid, the WTRU may use a second PRS configuration that may be determined to satisfy its validity condition; and/or

(3) When the first validity condition, e.g., expires and the second validity condition is found to be active during expiration of the first validity condition, the WTRU may change the first validity condition (e.g., associated with the first PRS configuration) to be similar to or the same as the second validity condition (e.g., associated with the second PRS configuration).

After or upon receiving the PRS configuration and the associated one or more validity conditions, the WTRU may perform PRS measurements using the configuration determined to be valid when or after receiving and/or detecting the trigger. For example, the trigger may include receiving any of the following: (i) LPP messages (e.g., LPP requests for location information), (ii) location service requests (e.g., MO-LR, MT-LR, and/or deferred MT-LT, etc.), and/or AS layer messages (e.g., via RRC signaling, MAC CE, and/or DCI).

In some representative embodiments, the WTRU may determine whether to begin using the new PRS configuration before or after the data link HO. A representative procedure may be implemented for the WTRU to determine whether to begin using the new PRS configuration associated with the target gNB/cell before or after the data link HO. For example, the representative process may avoid any positioning gaps, and may be based on one or more PRS configurations and/or one or more positioning mobility configurations. These configurations may include or may indicate or may include information (e.g., rules/conditions) indicating when to release/stop an existing PRS configuration and when to begin using a new PRS configuration during mobility. For example, the WTRU may receive one or more PRS configurations (e.g., a first PRS configuration associated with a serving cell and a second PRS configuration associated with a target cell) and a positioning mobility configuration from the LMF. The WTRU may receive a first RAN configuration (e.g., from a serving gNB) based on information related to the first PRS configuration provided by the WTRU to the serving base station/gNB (e.g., information including or indicating (i) a Measurement Gap (MG) configuration (e.g., for making PRS measurements), (ii) a CG configuration (e.g., for sending positioning reports)). The WTRU may perform PRS measurements using a first PRS configuration and a received RAN configuration while under coverage of a serving cell/gNB/base station (e.g., within a coverage area). If the positioning mobility configuration indicates that the second PRS configuration was started to be used prior to the data link HO and one or more associated conditions are met (e.g., the RSRP of the serving cell is below an RSRP threshold and/or the RSRP of a neighboring cell (e.g., a neighboring cell or a cell near the WTRU) is above the same or a different RSRP threshold), the WTRU may perform any of the following: (1) Determining a second RAN configuration (e.g., MG configuration or CG configuration) associated with the second PRS configuration, (2) sending information or an indication to the serving base station/gNB indicating the determined second RAN configuration associated with the second PRS configuration. The WTRU may, upon receiving information or an indication to use/activate a second RAN configuration (e.g., MG configuration or CG configuration), e.g., from a serving base station/gNB/cell: (i) Stopping and/or releasing using the first PRS configuration and/or the first RAN configuration, and/or (ii) starting to perform PRS measurements using the second PRS configuration and/or the second RAN configuration while within a coverage area of a serving cell (e.g., under a coverage area of the serving cell).

If the positioning mobility configuration indicates that the first PRS configuration continues to be used after the data link HO to the target base station/gNB/cell and its associated conditions are met (e.g., the RSRP of the neighbor cell is above an RSRP threshold), the WTRU may: (1) determining a second RAN configuration (e.g., MG configuration or CG configuration) associated with the second PRS configuration, (2) sending information or an indication to the serving base station or gNB after the data link HO indicating the determined second RAN configuration associated with the second PRS configuration and continued use of the first RAN configuration (e.g., MG configuration or CG configuration), (3) performing PRS measurements using the first PRS configuration and/or the first RAN configuration during and/or after the HO, (4) if information or an indication to use/activate the second RAN configuration (e.g., MG configuration or CG configuration) is received from the target base station/gNB/cell, the WTRU may: (i) Stopping and/or releasing use of the first PRS configuration and/or the first RAN configuration, and/or (ii) starting to perform PRS measurements using the second PRS configuration and/or the second RAN configuration when the WTRU is within a coverage area of a target base station/gNB/cell (e.g., when under a coverage area of the target cell).

The WTRU may send a measurement report to the network (e.g., base station, gNB, LMF, and/or network entity), which may include information indicating one or more PRS measurements and/or timing/duration information to start and/or stop use of the first PRS configuration and/or the second PRS configuration.

In some representative embodiments, the WTRU may dynamically switch between different positioning methods during HO.

A representative procedure for a WTRU to switch from a first location method (e.g., multiple RTTs) to a second location method (e.g., DL-TDoA) during HO may be implemented, for example, to ensure location service continuity. For example, the WTRU may receive configuration information associated with a first positioning method (e.g., a multi-RTT method) and a second positioning method (e.g., a DL-TDoA method) and trigger information indicating one or more trigger conditions/rules for starting/stopping use of the second positioning method (e.g., during or after HO).

The WTRU may perform PRS measurements or SRSp transmissions using the indicated configuration associated with the first positioning method. The WTRU may if a trigger condition for starting use of the second positioning method is met (e.g., the RSRP of the target/neighbor cell is above the RSRP threshold, and/or a HO command is received from the serving base station/gNB): (1) suspending use of the first positioning method, (2) starting use of the second positioning method (e.g., by performing PRS measurements using PRS configurations associated with the second positioning method), (3) sending information or an indication to the network (e.g., LMF and/or serving base station/gNB) indicating that trigger conditions/rules are met, and/or (4) sending a measurement report containing/including measurement information (e.g., which may be provided until such time as the first positioning method is suspended), and so forth.

If a trigger condition/rule for stopping the use of the second positioning method is met (e.g., RSRP of the source cell/gNB/base station is below the RSRP threshold, or a HO complete message is sent to the target cell/gNB/base station), the WTRU may: (1) ceasing to use the second positioning method, (2) resuming use of the first positioning method, and/or (3) sending information or an indication to the network (e.g., network entity, gNB, base station, and/or LMF) indicating that the trigger condition/rule is met, and/or (3) sending a measurement report containing/including measurement/measurement information (e.g., which may be provided until such time as the first positioning method is resumed), and so forth.

The WTRU may send a measurement report to the network (e.g., LMF or another network entity) that includes information indicating PRS measurements and/or timing for suspending/resuming use of the first positioning method and/or the second positioning method.

In some representative embodiments, the WTRU may select PRS configurations to use during mobility based on one or more validity conditions/rules.

A representative procedure for WTRU selection of PRS configurations to be used during mobility may be implemented (e.g., based on detection of one or more configured region validity conditions (e.g., based on one or more cell IDs)). For example, the WTRU may receive one or more PRS configurations and/or one or more region validity conditions indicating a mapping between one or more cell IDs in a validity region and associated PRS configurations. If one or more cell IDs indicated in the area availability condition are detected (e.g., RSRP of the detected cell is above an RSRP threshold during mobility), the WTRU may perform any of the following: (1) selecting a PRS configuration that matches at least one of the detected one or more cell IDs, (2) sending information or an indication to an LMF (e.g., a network entity) indicating the detected one or more cell IDs and/or the selected PRS configuration, (3) performing PRS measurements using the selected PRS configuration, and/or (4) sending a measurement report to a network (e.g., an LMF or another network entity) including information indicating timing of PRS measurements and/or use of different PRS configurations during mobility (e.g., mobility events such as HO and/or re-establishment procedures), and so forth.

In some representative embodiments, the WTRU may send one or more location reports to the LMF or other network entity during mobility, e.g., based on a reporting configuration.

Representative procedures in which the WTRU sends one or more location reports (e.g., based on a reporting configuration and/or detection of one or more mobility triggers) to the LMF may be implemented. For example, the WTRU may receive information (e.g., information including/regarding the cell ID to report and/or the periodicity of reporting) indicating one or more PRS configurations and/or one or more reporting configurations. The reporting configuration may be associated with one or more mobility triggers. The WTRU may perform PRS measurements using the received information indicating PRS configuration. If a mobility trigger is detected (e.g., neighbor cell ID is detected, and/or WTRU speed increases above a speed threshold), the WTRU may: (1) select a reporting configuration that matches the mobility trigger, (2) send a positioning report to the LMF or network entity (e.g., based on the selected reporting configuration (e.g., using a reporting periodicity associated with the indicated reporting configuration)), and/or (3) send a measurement report to the network (e.g., the LMF or network entity) that includes PRS measurements and/or timing of use of different reporting configurations during mobility (e.g., mobility events).

In some representative embodiments, the WTRU may use a first PRS configuration associated with the source base station/gNB/cell before and/or during HO (e.g., data link HO) and may use a second PRS configuration associated with the target gNB/cell after HO (e.g., data link HO). For example, the representative process may avoid any positioning gaps and may be based on one or more PRS configurations and/or one or more RSRP thresholds associated with PRS measurements. For example, the WTRU may receive configuration information from a network (e.g., a base station, a gNB, an LMF, and/or a network entity) indicating one or more PRS configurations. The configuration information may indicate, for example, any of the following: (1) A first PRS configuration associated with a source base station/gNB/cell, (2) a second PRS configuration associated with a target base station/gNB/cell; (3) One or more RSRP thresholds, the first RSRP value and the second RSRP threshold of which may be associated with measurements of PRS resources in the first PRS configuration and/or the second PRS configuration; and/or (4) one or more RRM RSRP thresholds associated with measurements of RRM resources (e.g., CSI-RS and/or SSB, etc.) of the source base station/gNB/cell and/or the target/neighbor base station/gNB/cell. The WTRU may receive further information from the serving base station/gNB/cell (e.g., source base station/gNB/cell) indicating: (1) Configuration and/or (2) activation indication/information, e.g., for triggering use of a first Measurement Gap (MG) configuration (e.g., for making measurements of PRS resources in a first PRS configuration). The WTRU may (1) perform measurements on PRS resources in a first PRS configuration and/or (2) perform measurements using a first MG configuration.

On a condition that a measured RSRP of PRS resources in the first PRS configuration is below a first RSRP threshold and/or a measured RSRP of RRM resources associated with a target base station/gNB/cell is above the first RRM RSRP threshold, the WTRU may send an indication/information to a serving base station/gNB/cell (e.g., source base station/gNB/cell) indicating to continue to use the first MG configuration during and/or after the HO (e.g., data link HO); and may send information associated with the second MG configuration (e.g., for measuring PRS resources in the second PRS configuration, e.g., after releasing/deactivating the first MG configuration). The WTRU may receive information from the serving base station/gNB/cell indicating use of the first MG configuration during and/or after the HO (e.g., data link HO) (e.g., via (1) an acknowledgement message in response to or after the WTRU sent information and/or (2) an indication message indicating not to release the first MG configuration after receiving the HO command). The WTRU may perform measurements of PRS resources in the first PRS configuration during and/or after a HO (e.g., a data link HO) and/or perform measurements using the first MG configuration.

On a condition that the measured RSRP of the resources in the first PRS configuration is below a second RSRP threshold and/or the measured RSRP of the RRM resources associated with the target base station/gNB/cell is above the second RRM RSRP threshold, the WTRU may send information indicating that the serving base station/gNB/cell (which may be, for example, the target base station/gNB/cell) requests a handover to the second MG configuration. The WTRU may receive information from the serving base station/gNB (which may be, for example, a target base station/gNB/cell) indicating the configuration and/or an activation indication to trigger use of the second MG configuration. The WTRU may perform measurements on PRS resources in a second PRS configuration and/or perform measurements using a second MG configuration. The WTRU may send one or more measurement reports to the network (e.g., base station, gNB, LMF, and/or network entity). For example, the measurement report may include timing information (e.g., a timestamp) indicating when the WTRU switched from using the first PRS configuration to the second PRS configuration.

In certain representative embodiments, methods, processes, apparatuses, and systems may be implemented to switch a WTRU from a first PRS configuration to a second PRS configuration after a HO (e.g., a PRS configuration based on multiple configurations associated with different base stations/gnbs/cells and/or thresholds (e.g., RSRP thresholds)). For example, the WTRU may switch from a first PRS configuration to a second PRS configuration (e.g., after a HO and/or another mobility event) based on PRS configurations of configurations associated with different base stations, gnbs, and/or cells. The handover may be further based on an RSRP threshold.

In various embodiments, based on the configured one or more PRS configurations and a threshold associated with PRS measurements (e.g., an RSRP threshold), the WTRU may use PRS configurations associated with previous serving base stations/gNB/cells (e.g., source base stations/gNB/cells) during and/or after a data link HO prior to switching to a second PRS configuration associated with the serving base stations/gNB/cells (e.g., target/neighbor gNB/cells), e.g., to avoid positioning gaps (e.g., any positioning gaps).

In some examples, the WTRU may receive one or more of the following from the network (e.g., LMF, gNB, and/or base station):

(1) A plurality of PRS configurations (e.g., a first PRS configuration and a second PRS configuration) (e.g., the first PRS configuration may be associated with a first base station, a gNB, and/or a cell (e.g., a source cell) that may be a serving base station, a gNB, and/or a cell, and the second PRS configuration may be associated with a second base station, a gNB, and/or a cell that may be a neighboring/non-serving base station, a gNB, and/or a cell (e.g., a target cell); and/or

(2) The PRS associated with the measurement of signals received from the base station/gNB/cell/TRP configures a handover threshold (e.g., the threshold may correspond to an RSRP value, an RSSI value, and/or an RSRQ value, etc.), and for example, the signals received from the base station/gNB/cell/TRP may correspond to PRS and/or non-PRS signals (e.g., RRM signals, CSI-RS, SSB signals, SRS, etc.). For example, the WTRU may use the PRS configuration switching threshold to switch from the first PRS configuration to the second PRS configuration when an RSRP value of a signal received from a base station/gNB/cell/TRP is above/below an RSRP threshold, or the like.

The WTRU may send an indication to a network/cell (e.g., a network entity such as an LMF, a base station, a gNB, a cell, and/or an AMF) to request a measurement gap configured to perform measurements on PRS resources associated with a first PRS configuration. For example, the WTRU may receive an indication from the first base station/gNB/cell, for example, that includes and/or contains information indicating the first measurement gap configuration.

The WTRU may perform a first set of one or more measurements on PRSs using a first PRS configuration and a first measurement gap configuration. During mobility, the WTRU may determine whether: (1) Performing HO from the first base station/gNB/cell to the second base station/gNB/cell, performing cell selection or performing cell reselection; and/or (2) switch from the first PRS configuration to the second PRS configuration based on detecting one or more of the following events:

(1) The RRM measurements of the neighboring cells (e.g., CSI-RS and/or SSB of the neighboring cells) are above/below one or more RRM thresholds, e.g., configured by the network (e.g., network entity, LMF, AMF, gNB, and/or base station, etc.). The RRM measurement/RRM threshold may be based on RSRP, RSSI, RSRQ, and/or the like;

(2) For example, when monitoring System Information Blocks (SIBs) and/or when performing neighbor cell measurements, one or more SIBs associated with neighbor/target cells and/or SIB-related information (e.g., cell ID, posSIB) is detected; and/or

(3) For example, when one or more PRS configurations are used, PRS measurements above/below one or more thresholds (e.g., using RSRP, RSSI, and/or RSRQ, etc.) (e.g., when the RSRP of a PRS received from a source cell (e.g., a first cell) is below a first RSRP threshold and/or above a second RSRP threshold, the WTRU may determine to HO from the first cell to the second cell and/or to switch from the first PRS configuration to the second PRS configuration, where PRS received from the source cell may be associated with the first PRS configuration, when the RSRP of a PRS received from a neighbor/target cell (e.g., a second cell) is above the first RSRP threshold and/or below the second RSRP threshold, the WTRU may determine to HO from the first cell to the second cell and/or to switch from the first PRS configuration to the second PRS configuration, where PRS received from the neighbor/target cell may be associated with the second PRS configuration), and so on.

The WTRU may: (1) sending an indication to the first base station/gNB/cell indicating HO, (2) performing cell selection or reselection from the first base station/gNB/cell to the second base station/gNB/cell, and/or (3) switching from using the first PRS configuration to the second PRS configuration based on detection of one or more event/trigger conditions (e.g., event/trigger conditions described above), and so forth. The WTRU may indicate (e.g., also indicate) to the network (e.g., network entity, LMF, and/or serving first base station/gNB/cell) a request to maintain a first PRS configuration after HO and/or to maintain a first measurement gap configuration associated with the first base station/gNB/cell.

An indication to maintain the first PRS configuration and/or the first measurement gap configuration may be sent by the WTRU, for example, due to one or more of: (1) For example, an indication from a network (e.g., an LMF or other network entity) that the WTRU may send an indication to request continued use of the first PRS configuration (e.g., after receiving an indication from the LMF (e.g., after receiving assistance data and/or configuration), which indicates continued use of the first PRS configuration after HO (e.g., when under coverage of a neighbor/target base station/gNB/cell)); and/or (2) PRS measurements (e.g., the WTRU may send an indication when PRS measurements made by the WTRU using the first PRS configuration and/or the second PRS configuration are, for example, above a first RSRP threshold and/or below a second RSRP threshold).

The WTRU may receive a HO request/command from a first base station/gNB/cell to handover to a second base station/gNB/cell. The WTRU may receive an indication along with the HO request/command and/or in a separate indication (e.g., RRC message and/or MAC CE, etc.) from the first base station/gNB/cell indicating that the first measurement gap configuration is maintained after the HO is performed. For example, upon or after receiving the HO request/command, the WTRU may perform a HO, and after the HO, the second base station/gNB/cell (e.g., target cell) may become the serving cell and the first cell may become the non-serving cell.

The WTRU may perform a second set of measurements on PRSs using the first PRS configuration and the first measurement gap configuration. The WTRU may then perform one or more of the following based on the second set of PRS measurements: (1) The WTRU may perform a third set of measurements on PRSs using the first PRS configuration and the first measurement gap configuration on a condition that the second set of PRS measurements is greater than or equal to a PRS configuration handover threshold; (2) On the condition that the second set of PRS measurements is less than or equal to the PRS configuration switching threshold, the WTRU may send an indication to the serving base station/gNB/cell to request configuration and/or activate a measurement gap associated with the second PRS configuration. The WTRU may receive information/indications from the serving base station/gNB/cell that includes or includes configuration information and/or activation indications for configuration using the second measurement gap. The WTRU may perform a fourth set of measurements on PRSs using a second PRS configuration and a second measurement gap configuration.

After performing measurements on PRSs during HO, the WTRU may send measurement reports to the network (e.g., LMF and/or serving base station/gNB) indicating at least a third set of PRS measurements and/or a fourth set of PRS measurements made by the WTRU. For example, if switching between different PRS configurations, the WTRU may send information/indications (e.g., IDs of first PRS configuration and/or second PRS configuration) indicating which PRS configurations to use during HO and/or timing information (e.g., a timestamp) indicating when the WTRU switches from using the first PRS configuration to the second PRS configuration.

Representative procedure/method for supporting location service continuity for UL-based positioning

In one class of solutions, the WTRU performs location service continuity based on UL-SRSp transmissions. For example, the WTRU may perform UL-based positioning by transmitting UL-SRSp during mobility and while experiencing a data link HO from a source/serving TRP/gNB/cell to one or more target TRP/gNB/cells. The resources used to transmit the SRSp are allocated to the WTRU by the network (e.g., serving gNB). Typically, one or more neighboring cells/TRP/gnbs are configured by a network (e.g., an LMF and/or RAN entity and/or base station) to receive and measure SRSp transmitted by the WTRU. When the WTRU experiences a data link HO from the source gNB to the target gNB, the WTRU may be instructed by the serving gNB to release resources for SRSp transmission. The WTRU may then be reconfigured with the same or different SRSp resources by the target gNB after HO. In addition, it is possible that the network may reconfigure one or more existing TRP/gnbs or add new TRP/gnbs for receiving SRSp transmitted by the WTRU based on WTRU mobility and/or HO so that the location of the WTRU may be determined with high accuracy.

In another class of solutions, the WTRU may send a location related report to the network for updating the TRP/gNB, which may receive the UL-SRSp transmitted by the WTRU. For example, the WTRU may be configured to determine and send a location related report to the network regarding whether one or more target/neighbor cells are capable of receiving SRSp transmitted by the WTRU during WTRU mobility. In this case, the WTRU may be configured with a mapping between the SRSp and a group including one or more target TRP/cells (e.g., cell IDs) configured to receive the SRSp transmitted by the WTRU. Since the WTRU may also be configured to make RRM measurements, possibly for facilitating data link HO, the WTRU may determine/detect target/neighbor cells based on the RRM measurements and identify the corresponding cell ID. The WTRU may then report to the serving cell when determining whether the target cell is within an existing mapping between srsps configured in the WTRU and a cell list of measurable srsps. For example, the WTRU may report (e.g., in RRC signaling, UL MAC CE, and/or UCI) to the serving cell indicating one or more detected target cell IDs that are not present in the mapping that shows the association between SRSp configured in the WTRU and the target cell list. Based on the report sent by the WTRU, the network may configure a new target cell for receiving and measuring SRSp. The WTRU may receive an updated mapping that may include the new target cell in the cell list. For example, the WTRU may also receive a new/updated SRSp configuration for support during mobility.

To minimize the delay associated with a new target cell configured to receive SRSp transmitted by the WTRU, the WTRU may be configured with one or more location service continuity conditions that the WTRU may monitor and report to the network when triggered by these conditions. For example, the WTRU may be configured with a UL-based positioning measurement threshold such that RSRP measurements made on SSBs, CSI-RSs, and/or PRSs transmitted by the target cell may exceed the threshold and/or remain above the threshold for a duration. The measurement threshold configured for UL-based positioning may be lower than or equal to the threshold configured for RRM measurements associated with the data link HO. Alternatively or additionally, the WTRU may be configured with service continuity conditions related to the detection of a new target cell ID, in which case the WTRU may detect the new target cell ID (e.g., in SIB/SSB) during mobility or when an obstruction between the WTRU and the target cell is cleared. Alternatively or additionally, the WTRU may be configured with service continuity conditions related to WTRU mobility attributes, such as a change in WTRU speed, direction, orientation, etc. by a predetermined or dynamically determined threshold.

The WTRU may indicate information (e.g., target cell ID, measurements) related to location service continuity conditions when reported to the network. Transmitting the report when the location service continuity condition is triggered in advance may enable the network to perform reconfiguration of the target TRP/gNB/cell with low delay and/or before the WTRU experiences a HO.

In another solution, a WTRU configured with a mapping between srsps and associated TRP/gNB/cells that may receive srsps transmitted by the WTRU may send a request to a serving gNB to change an existing SRSp configuration. In this case, the WTRU may send a request to the serving gNB to change/update the SRSp, for example, when one or more of the configured location service continuity conditions described above are detected. The WTRU may then receive the updated/new SRSp configuration from the serving gNB. For example, the WTRU may receive a new/updated SRSp configuration when signaling associated with the data link HO (e.g., RRC reconfiguration message and/or HO command) is received.

In another class of solutions, the WTRU may be configured with SRSp usage rules for using SRSp configuration. For example, the WTRU may be (pre) configured with one or more resources/resource sets associated with the SRSp configuration and an SRSp usage rule indicating when and how to start/stop using the triggering and validity of the SRSp configuration. In this case, the WTRU may receive SRSp configuration and/or SRSp usage conditions from the RAN. Alternatively or additionally, the WTRU may receive the SRSp configuration from the RAN and at least a portion of the SRSp usage rules from the LMF. The SRSp usage rules received by the WTRU may be associated with at least one SRSp configuration. The SRSp usage rules may indicate that transmission of an associated SRSp configuration (e.g., an ID of the SRSp configuration) is started/stopped when triggered by various conditions.

Exemplary conditions for starting/stopping transmission of an associated SRSp configuration include detection of a target/neighbor cell ID. For example, the rule of configuration may indicate that the first SRSp configuration is used when a target cell ID (e.g., in SIB/SSB) within a set of TRP/gnbs associated with the first SRSp configuration is detected. For example, similar rules may apply for using the second SRSp configuration.

Another exemplary condition for starting/stopping transmission of an associated SRSp configuration includes RRM/PRS measurements of one or more target TRP/gnbs. For example, the configured rules may indicate that a first SRSp configuration is used when the measured RSRP value (e.g., on the received SSB and/or PRS) is above/below a first threshold and a second SRSp configuration is used when the measured RSRP value is above/below a second threshold.

Another exemplary condition for starting/stopping transmission of an associated SRSp configuration includes a validity area. For example, one or more SRSp configurations pre-configured in the WTRU may be associated with a validity area consisting of a set of one or more TRP/gnbs. In this case, the WTRU may use the first SRSp configuration whenever the WTRU moves or experiences a HO from the source cell to the target cell within the validity area (e.g., one or more target TRP/gNB/cell IDs detected by the WTRU or experiencing a data link HO are within the validity area group). Based on the rules of configuration, the WTRU may cease using the first SRSp configuration and begin using the second SRSp configuration when a different TRP/gNB is detected during mobility.

Another exemplary condition for starting/stopping transmission of an associated SRSp configuration includes a validity time. For example, one or more SRSp configurations may be associated with a validity duration. The WTRU may start/stop using the SRSp configuration based on the setting/expiration of a timer for the validity duration of the configuration.

Another exemplary condition for starting/stopping transmission of an associated SRSp configuration includes one or more WTRU mobility attributes. For example, the configured rule may indicate that the first SRSp configuration is used when the WTRU speed is within a first range (e.g., upper and lower threshold speed values). The rule may also indicate that a second SRSp configuration is used when the WTRU speed is within a second range.

For example, in the event that one or more trigger conditions are not met (e.g., the WTRU detects a new target cell ID that is outside of one of the TRP/gNB groups and associated srsps configured in the WTRU), the WTRU may send an indication to the network to request a new SRSp configuration and/or new SRSp usage rules.

In another class of solutions, the WTRU may receive SRSp configurations associated with the target gNB via the serving gNB before/during HO. For example, the WTRU may be configured with an SRSp configuration by the source gNB, which may be determined based on coordination with the target gNB during WTRU mobility. In one example, the WTRU may be configured with SRSp for UL-based positioning by the source/serving gNB. When the WTRU experiences a potential data link HO to the target gNB, the source gNB may ensure support for location service continuity, where the WTRU may continue to transmit SRSp before and/or during HO without interruption.

The WTRU may indicate support for location service continuity to the network and, possibly based on the indication, the serving gNB may determine appropriate resources and SRSp configurations to allocate to the WTRU. The WTRU may send the indication to support location service continuity in a separate message (e.g., in RRC signaling, UL MAC CE, and/or UCI) or along with RRM measurements to facilitate data link HO.

The serving gNB may identify a target gNB based on the WTRU indication/report and coordinate with the target gNB (e.g., via HO signaling over Xn) to determine SRSp configurations to provide to the WTRU. In this case, a WTRU that may be configured with a first SRSp configuration may receive a second SRSp configuration to be used during and after the data link HO. For example, the second SRSp configuration may be associated with resources allocated by the target gNB, which may be indicated to the serving gNB during the HO procedure. The WTRU may receive the second SRSp configuration prior to or in conjunction with the RRC reconfiguration message containing the HO command. The WTRU may also receive one or more conditions associated with when to start/stop using the second SRSp configuration. For example, the WTRU may begin using the second SRSp configuration upon receiving a HO command from the serving cell and/or releasing the first SRSp configuration. For example, the WTRU may cease using the second SRSp configuration upon receiving an RRC reconfiguration indication from the target gNB, which may be received after the HO and/or after establishing a connection with the target gNB.

In another example, the WTRU may use the first SRSp configuration before HO to the target gNB (e.g., before and/or after receiving a HO command) and begin using the second SRSp configuration immediately after HO (e.g., after transmitting RACH and/or RRC signaling for connectivity establishment with the target gNB). For example, receiving an SRSp configuration prior to experiencing a data link HO may enable a WTRU to support location service continuity for UL-based positioning with low latency.

In another class of solutions, the WTRU may assist the RAN in performing a data link HO based on the SRSp transmission. For example, the WTRU may assist in performing a data link HO from the source cell to the target cell based on the selection of the appropriate SRSp configuration and the transmission of the selected SRSp. The WTRU may be (pre) configured with one or more SRSp configurations for supporting UL-based positioning. The WTRU may also be configured with one or more rules indicating when to start/stop using the SRSp (pre) configuration. In this case, the rules may indicate that the first SRSp configuration is used until the target gNB/cell ID is detected (e.g., via RRM measurements, or neighboring cell SIBs), and then the second SRSp configuration is used. The receipt of the SRSp at the serving and/or target gnbs (e.g., using a second SRSp configuration) may trigger the data link HO procedure.

In another example, the WTRU may select the SRSp configuration from the (pre) configuration set based on an indication from the network indicating support Condition HO (CHO). In this case, the WTRU may select an SRSp configuration that may have a different Tx power level (e.g., higher than an existing SRSp intended for a conventional HO) so that the SRSp may be received by multiple TRPs/gnbs with better RSRP. For example, the RAN may then identify a potential target gNB for CHO by determining a subset of target gnbs that may receive srsps transmitted by the WTRU above a certain RSRP threshold. For example, the WTRU may then receive conditions associated with CHO procedures from the serving gNB, which may be used by the WTRU to evaluate and/or determine a target gNB for HO.

In some representative embodiments, the WTRU may determine an SRSp configuration to be used during mobility (e.g., detection of a configured mobility trigger).

A representative procedure for the WTRU to determine SRSp configuration to use for UL positioning during mobility (e.g., detection of a configured mobility trigger) may be implemented. For example, the WTRU may send information or an indication to the serving base station/gcb (e.g., to indicate the capability/capability information of the WTRU to support location service continuity during mobility).

The WTRU may receive any of the following: (1) one or more SRSp configurations, (2) one or more validity conditions associated with the SRSp configurations (e.g., RAN notification area and/or TA timer/timing information, etc.), and/or (3) one or more SRSp usage rules (e.g., detection based on mobility trigger) indicating when to start and/or stop using the SRSp configurations (e.g., one or more RSRP measurements and/or receipt of HO commands for neighboring cells above the RSRP threshold).

If a mobility trigger is detected, the WTRU may: (1) Selecting an SRSp configuration that satisfies one or more validity conditions, and/or (2) sending information or an indication to the serving base station/gNB indicating the selected SRPp configuration. The WTRU may perform the SRSp transmission using the selected SRSp configuration based on the SRSp usage rules, e.g., after or upon receiving information or indication from the gNB, base station, and/or network entity indicating activation of the SRSp configuration.

Representative procedure/method for supporting location service continuity based on handover between different location methods

In some representative embodiments, the WTRU may support a location service continuity procedure with LPP. For example, the WTRU may receive one or more RAN configurations associated with a location to be applied during mobility. The WTRU may use one or more validity conditions to determine PRS configurations to apply during mobility.

In some representative embodiments, the WTRU may determine whether to begin using the new PRS configuration before or after the data link HO.

In some representative embodiments, the WTRU may dynamically switch between different positioning methods during HO.

In some representative embodiments, the WTRU may select PRS configurations to use during mobility based on validity conditions.

In some representative embodiments, the WTRU may send one or more location reports to the LMF or other network entity during mobility based on the reporting configuration.

In some representative embodiments, the WTRU may determine the SRSp configuration to use during mobility based on detection of configured mobility triggers.

Fig. 5 is a graphical illustration depicting timing of operations before, during, and after HO, according to one embodiment.

Referring to fig. 5, a wtru may switch to a different location method during HO to ensure location service continuity. For example, the WTRU may switch from the first positioning method at 500A to the second positioning method at 502 for the duration 504 of the data link HO, possibly back to the first positioning method at 500B after the HO. In this case, the WTRU may be configured to perform DL and UL based positioning methods (e.g., multiple RTTs) by the serving gNB. For this multi-RTT positioning method, the WTRU may perform measurements on DL-PRSs received from a set of TRP/gnbs for a first duration and transmit UL-srsps to the set of TRP/gnbs for a second duration. For example, the positioning information of the WTRU may be determined based on RTT taken by PRS and SRSp to traverse between the network node and the WTRU.

In order to support location service continuity, the WTRU may be configured with at least a second location method in addition to the first location method in the case where location related measurements may be supported when undergoing a data link HO. For example, where the WTRU is configured with multiple RTTs as the first positioning method, the WTRU may also be configured by the network with DL-PRS based or UL-SRSp based as the second positioning method performed at 504. The WTRU may also be configured with one or more location service continuity conditions as described above for determining when to switch from the first method to the second method. In one example, the WTRU may be configured to perform multi-RTT positioning by measuring DL-PRS and transmitting UL-SRSp before detecting a positioning service continuity condition (e.g., receipt of RRC reconfiguration message/HO command), and may switch to performing measurement (e.g., measurement only) of DL-PRS for the duration of the HO. Upon establishing a connection with the target gNB (e.g., upon performing RRC signaling transmission/reception), the WTRU may switch back to performing multiple RTTs.

For example, a temporary handoff from a first positioning method at 500A to a second positioning method at 504 during HO may allow for a modest degradation in positioning accuracy and reliability performance. When switching from one positioning method to another, the WTRU may send an indication to the network (LMF and/or RAN) in RRC signaling, MAC CE, and/or UCI. For example, the WTRU may send an indication to instruct handover to another positioning method along with signaling associated with the data link HO (e.g., RRC signaling including measurement reports, RACH messages). For example, the WTRU may be configured to use and switch between one or more different second positioning methods during the HO, wherein the different positioning methods used by the WTRU may be related/aligned with signaling associated with the data link HO.

In one example, the WTRU may be configured to use the DL-TDoA location method prior to HO, and during HO the WTRU may switch to using the multi-RTT method. Upon completion of the HO, the WTRU may switch back to using DL-TDoA. Achieving a certain positioning accuracy by using DL-ToA may require timing synchronization between WTRU and TRP/gcb. For example, since there may be a certain duration during the HO during which the WTRU may lose synchronization with the serving gNB and/or may not synchronize with the target gNB, the WTRU may use a positioning method during the HO that may have looser synchronization requirements with the network, such as a multi-RTT or DL-AoD method. In this case, a second positioning method with relaxed synchronization may be used in the associated duration where the WTRU may not synchronize with the network and/or based on a synchronization related trigger. For example, the WTRU may then switch to using the DL-TDoA method when synchronization is established with the target gNB.

In another example, the handover point may be determined by the WTRU based on monitoring of WTRU mobility attributes and/or WTRU radio environment with/without network assistance. For example, when the WTRU detects an increase in delay or a decrease in positioning measurement accuracy (e.g., RSRP of PRS is below a threshold) while measuring DL-PRS (possibly due to an increase in WTRU speed), the WTRU may switch to performing UL-SRSp transmissions for a duration while performing HO. The WTRU may then switch back to measuring DL-PRS when sending a handover indication to the network after HO.

In the case of using a multi-RTT method including both DL-based and UL-based methods, the WTRU may be (pre) configured with DL-PRS configuration and UL-SRSp configuration, and both configurations may be activated prior to HO. When the WTRU experiences a HO, one of these methods/configurations may be deactivated for the duration of the HO and then activated when the HO is complete. Signaling associated with activating/deactivating one or more positioning methods may be received by the WTRU from the network in RRC signaling, MAC CE, and/or DCI. For example, in the case when the WTRU determines activation/deactivation of a location method based on detection of one or more location service continuity conditions, the WTRU may send an activation/deactivation indication to the network in RRC signaling, MAC CE, and/or UCI.

Representative procedures/methods implemented in a WTRU to support location services continuity

Fig. 6 is a flow chart illustrating a representative method implemented by a WTRU.

Referring to fig. 6, an exemplary method 600 implemented in WTRUs 102, 200, 300, 400, and 500 may support location service continuity. At block 610, the WTRU 102 may receive configuration information indicating a configuration for supporting location service continuity during a HO. For example, and as further detailed herein, the WTRUs 102, 200, 300, 400, and 500 may receive a configuration for performing support of location service continuity for DL location and/or UL location. Alternatively or additionally, the WTRUs 102, 200, 300, 400, and 500 may receive information/configuration for switching between positioning methods prior to and/or during a data link HO. The operation may proceed from block 610 to block 620.

At block 620, the WTRUs 102, 200, 300, 400, and 500 may support location service continuity based at least in part on the configuration by determining one or more transmissions to perform. For example, the WTRUs 102, 200, 300, 400, and 500 may use a new PRS configuration associated with a target gNB/base station under the coverage of and/or when connected to a source gNB/base station as previously described with reference to fig. 2. Alternatively or additionally, the WTRUs 102, 200, 300, 400, and 500 may use existing PRS configurations associated with a source gNB/base station under the coverage of and/or when connected to a target gNB/base station as previously described with reference to fig. 3. Alternatively or additionally, the WTRUs 102, 200, 300, 400, and 500 may use the existing PRS configuration associated with the source gNB/base station and the new PRS configuration associated with the target gNB/base station during the data link HO as previously described with reference to fig. 4. Alternatively or additionally, the WTRUs 102, 200, 300, 400, and 500 may use a first positioning method prior to the data link HO and switch to a second positioning method during the data link HO, as previously described with reference to fig. 5. The operation may proceed from block 620 to block 630.

At block 630, the WTRUs 102, 200, 300, 400, and 500 may assist the radio access network in data link HO by performing one or more transmissions according to the configuration. For example, in supporting location service continuity for DL positioning, the WTRUs 102, 200, 300, 400, and 500 may send information about the positioning measurements to the radio access network to assist the data link HO. Alternatively or additionally, the WTRUs 102, 200, 300, 400, and 500 may perform UL-SRSp transmissions while supporting location service continuity for DL positioning.

In some implementations, the WTRUs 102, 200, 300, 400, and 500 support positioning service continuity for DL positioning and the configuration is at least one PRS configuration. In these implementations, the method 600 may include various operations or steps specific to these implementations. For example, the method may include performing positioning service continuity based on PRS/RRM measurements and/or sending a request for a new PRS configuration message to a serving gNB/base station. Alternatively or additionally, the method may include at least one of transmitting a positioning service continuity report and/or receiving a new PRS configuration or an updated PRS configuration in response to the positioning service continuity report. Alternatively or additionally, the method may include using PRS configuration of the target gNB in the coverage area of the source gNB/base station prior to the data link HO, using PRS configuration of the source gNB/base station in the coverage area of the target gNB/base station after the data link HO, and/or using PRS configuration of the source gNB/base station and PRS configuration of the target gNB/base station during the data link HO. Alternatively or additionally, the method may include determining, based on the measurement gap configuration, a use of two or more PRS configurations including at least a PRS configuration of the source gNB/base station and a PRS configuration of the target gNB/base station, and/or transmitting information about positioning measurements to the radio access network to assist the data link HO.

In some implementations, the WTRUs 102, 200, 300, 400, and 500 support location service continuity for UL location and the configuration includes one or more SRSp configurations and SRSp usage rules for using the one or more SRSp configurations. In these implementations, the method 600 may include various operations or steps specific to these implementations. For example, the method may include performing location service continuity based on UL-SRSp transmissions and/or transmitting location related reports to the radio access network for updating TRP/gnbs, which may receive UL-srsps transmitted by WTRUs 102, 200, 300, 400, and 500. Alternatively or additionally, the method may include receiving, via the serving gNB/base station, an SRSp configuration associated with the target gNB/base station at least one of before or during the data link HO. Alternatively or additionally, the method may comprise assisting the radio access network in performing the data link HO based on the transmission of the UL-SRSp.

In some embodiments, the WTRUs 102, 200, 300, 400, and 500 may use a first positioning method prior to a data link handoff and may switch to a second positioning method during the data link handoff.

Fig. 7 is a flow chart illustrating another exemplary method implemented by a WTRU.

Referring to fig. 7, the exemplary method 700 may include the WTRUs 102, 200, 300, 400, and 500 receiving information indicating: (1) a first Positioning Reference Signal (PRS) configuration associated with a first cell, (2) a second PRS configuration associated with a second cell, and (3) a Measurement Gap (MG) configuration. At block 720, the WTRUs 102, 200, 300, 400, and 500 may perform a first PRS measurement on a first transmission from a first cell using a first PRS configuration and an MG configuration. At block 730, the WTRUs 102, 200, 300, 400, and 500 may send a request to a first Network Entity (NE) associated with a first cell, the request including information indicating to maintain an MG configuration after performing a Mobility Event (ME) associated with a second cell. At block 740, the WTRUs 102, 200, 300, 400, and 500 may receive information indicating: (1) Executing the ME associated with the second cell, and (2) maintaining the MG configuration after executing the ME. At block 750, the WTRUs 102, 200, 300, 400, and 500 may perform a second PRS measurement on a first transmission or further transmission from a first cell using a first PRS configuration and an MG configuration after performing the ME. At block 760, the WTRUs 102, 200, 300, 400, and 500 may send information indicating a second PRS measurement to a second NE associated with the first cell.

For example, WTRUs 102, 200, 300, 400, and 500 may receive (e.g., from a base station, LMF, and/or NE): (1) a first PRS configuration; (2) A second PRS configuration (e.g., where a first PRS configuration may be associated with a first cell (e.g., a source cell) and a second PRS configuration may be associated with a second cell (e.g., a target cell); (3) PRS switching thresholds, and (4) one or more Reference Signal Received Power (RSRP) thresholds (e.g., a first RSRP threshold and a second RSRP threshold). The WTRUs 102, 200, 300, 400, and 500 may perform a first PRS measurement (e.g., of PRSs from a first cell) using a first PRS configuration and a first MG configuration (received from the first cell).

When one or more first PRS measurements meet RSRP threshold criteria (e.g., when PRS measurements are above a first threshold and/or below a second threshold), WTRUs 102, 200, 300, 400, and 500 may send a request to a first cell to maintain a first MG configuration after HO.

The WTRUs 102, 200, 300, 400, and 500 may receive a HO indication from a first cell indicating a HO to a second cell, and an indication to maintain a first MG configuration during and/or after the HO.

After the HO to the second cell, the WTRUs 102, 200, 300, 400, and 500 may perform a second PRS measurement. The second PRS measurements may be performed/made using a first PRS configuration and a first MG configuration of the first cell.

The WTRUs 102, 200, 300, 400, and 500 may determine whether the second PRS measurement meets (e.g., is less than) a PRS switching threshold. If the PRS switching threshold is not met, the WTRUs 102, 200, 300, 400, and 500 may send reports (e.g., to the LMF). The report may include an indication of the second PRS measurements and/or a first PRS configuration Identifier (ID) used during the HO. If the PRS switching threshold is met, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following: (1) Transmitting a request for a second MG gap configuration associated with a second PRS configuration to a second cell; (2) receiving information indicative of a second MG configuration; (3) Performing a third PRS measurement using a second PRS configuration and a second MG configuration; (4) A report is sent (e.g., to the LMF) that includes an indication of the second PRS measurement, the third PRS measurement, and/or the second PRS configuration ID and a time (e.g., a timestamp) indicating when the WTRU switched from the first PRS configuration to the second PRS configuration.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may determine to send a request to the first cell indicating to maintain MG configuration after the ME is performed.

In some embodiments, the first NE associated with the first cell and the second NE associated with the first cell may be one base station, or the first NE may be a first base station and the second NE may be a Location Management Function (LMF) entity.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following on the condition that the second PRS measurement does not meet the PRS ME threshold: (1) Sending a request for further MG configuration to a first NE associated with a second cell; (2) receiving information indicative of further MG configuration; (3) Performing a third PRS measurement on transmissions from the second cell using the second PRS configuration and a further MG configuration; and/or (4) send further information to a second NE associated with the second cell indicating any of: (1) a third PRS measurement, (2) a second PRS configuration, and/or (3) a time when the WTRU starts to use the second PRS configuration.

In some embodiments, the first NE associated with the first cell and the second NE associated with the first cell may be a single base station, or the first NE associated with the first cell may be a first base station and the second NE associated with the first cell may be an LMF entity. The first NE associated with the second cell and the second NE associated with the second cell may be another single base station, or the first NE associated with the second cell may be the second base station and the second NE associated with the second cell may be an LMF entity.

In certain representative embodiments, the ME may be any of the following: (1) switching; or (2) reselection, and the WTRUs 102, 200, 300, 400, and 500 may perform a handover or reselection of the WTRUs 102, 200, 300, 400, and 500 to the second cell.

In some embodiments, the further information may be included in a location services continuity report. The WTRUs 102, 200, 300, 400, and 500 may receive new PRS configurations or updated PRS configurations in response to or after a location service continuity report. The new PRS configuration or the updated PRS configuration may be associated with a target NE or a first NE associated with a second cell.

In some representative embodiments, performing the second PRS measurement on the first transmission or the further transmission from the first cell using the first PRS configuration and the MG configuration after performing the ME may include the WTRUs 102, 200, 300, 400, and 500 performing the first PRS measurement on the first transmission from the first cell using the first PRS configuration associated with the first cell in a coverage area of the second cell after the data link handover.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform further PRS measurements on transmissions from a second cell in a coverage area of a first cell using a second PRS configuration associated with the second cell prior to performing ME.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform (1) further PRS measurements on transmissions from a first cell using a first PRS configuration of the first cell and (2) further PRS measurements on transmissions from a second cell using a second PRS configuration of the second cell during ME.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may switch from the first positioning method to the second positioning method during ME.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may receive information indicating the use, activation, or deactivation of one or more of the PRS configurations.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may trigger the performance of the second PRS measurement in response to or after the ME. For example, (1) execution of the first PRS measurements may use the first PRS configuration and the MG configuration prior to execution of the ME, and/or (2) execution of the second PRS measurements may use the first PRS configuration and the MG configuration during at least a first portion of the ME. The WTRUs 102, 200, 300, 400, and 500 may perform further PRS measurements (1) during at least a second portion of the ME and/or (2) after performing the ME using a second PRS configuration and a second MG configuration.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following: (1) receiving information associated with: (i) a first positioning operation, (ii) a second positioning operation, and/or (iii) one or more trigger conditions for starting and/or stopping use of the second positioning operation; and/or (2) initiate use of the second positioning operation if one or more trigger conditions are met to begin use of the second positioning operation. For example, (1) execution of the first PRS measurements may use a first PRS configuration associated with a first positioning operation and/or (2) execution of the second PRS measurements may use a second PRS configuration associated with a second positioning operation.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform the second PRS measurements using a second PRS configuration associated with a second positioning operation in response to the ME or triggered after the ME. For example, (1) execution of the first PRS measurements may use a first PRS configuration (i) before execution of the ME and/or (ii) during at least a first portion of the ME, and/or (2) execution of the second PRS measurements may use a second PRS configuration (i) during at least a second portion of the ME and/or (ii) after execution of the ME.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may receive report configuration information indicating a plurality of report configurations. For example, each reporting configuration indicated may be associated with a trigger condition type associated with the ME. The WTRUs 102, 200, 300, 400, and 500 may send location reports to the LMF entity based on the trigger condition type associated with the ME. For example, the trigger condition type associated with the ME may include any of the following: (1) A speed related trigger condition associated with WTRUs 102, 200, 300, 400, and 500; (2) a rate related trigger condition associated with the WTRU; (3) A movement direction related trigger condition associated with WTRUs 102, 200, 300, 400, and 500; (4) Orientation related trigger conditions associated with WTRUs 102, 200, 300, 400, and 500; (5) Environmental related trigger conditions associated with WTRUs 102, 200, 300, 400, and 500; (6) Indoor/outdoor status related triggers associated with WTRUs 102, 200, 300, 400, and 500; and/or (7) neighbor cells detect/discover related trigger conditions.

In certain representative embodiments, a first reporting configuration of the indicated plurality of reporting configurations may include first periodicity information and a second reporting configuration of the indicated plurality of reporting configurations may include different second periodicity information.

Fig. 8 is a flow chart illustrating a further exemplary method implemented by a WTRU.

Referring to fig. 8, the representative method 800 may include the WTRUs 102, 200, 300, 400, and 500 receiving information indicating: (1) a first Positioning Reference Signal (PRS) configuration associated with a first cell, (2) a second PRS configuration associated with a second cell, and (3) a first Measurement Gap (MG) configuration associated with the first cell. At block 820, the WTRUs 102, 200, 300, 400, and 500 may perform a first PRS measurement on a first transmission from a first cell using a first PRS configuration and an indicated first MG configuration prior to a Handover (HO). At block 830, the WTRUs 102, 200, 300, 400, and 500 may determine whether to use the indicated first MG configuration or a further MG configuration associated with the second cell on a HO-occurring condition. At block 840, the WTRUs 102, 200, 300, 400, and 500 may send a request for further MG configuration to a first Network Entity (NE) associated with the second cell if the further MG configuration is to be used. At block 850, the WTRUs 102, 200, 300, 400, and 500 may receive information indicating further MG configurations. At block 860, the WTRUs 102, 200, 300, 400, and 500 may perform second PRS measurements on transmissions from the second cell using the second PRS configuration and further MG configuration after the HO. At block 870, the WTRUs 102, 200, 300, 400, and 500 may send information to a second NE associated with a second cell indicating any of: (1) a second PRS measurement, (2) a second PRS configuration, and/or (3) a time (e.g., a timestamp) at which the WTRU starts to use the second PRS configuration.

In some representative embodiments, determining whether to use the indicated first MG configuration associated with the first cell or the further MG configuration associated with the second cell may include determining whether the first PRS measurement meets a PRS ME threshold.

In some representative embodiments, the information sent to the second NE associated with the second cell may be included in a location services continuity report. In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may receive new PRS configurations or updated PRS configurations in response to or after a location service continuity report. For example, the new PRS configuration or the updated PRS configuration may be associated with a target NE or a first NE associated with a second cell.

In some representative embodiments, (1) the first NE associated with the first cell and the second NE associated with the first cell may be a single base station, or (2) the first NE associated with the first cell may be a first base station and the second NE associated with the first cell may be an LMF entity.

In some embodiments, (1) the first NE associated with the second cell and the second NE associated with the second cell may be another single base station, or (2) the first NE associated with the second cell may be the second base station and the second NE associated with the second cell may be an LMF entity.

Fig. 9 is a flow chart illustrating an additional exemplary method implemented by a WTRU.

Referring to fig. 9, the exemplary method 900 may include the WTRUs 102, 200, 300, 400, and 500 receiving information indicating: (1) A Positioning Reference Signal (PRS) configuration associated with a first cell, and (2) a Measurement Gap (MG) configuration. At block 920, the WTRUs 102, 200, 300, 400, and 500 may receive information indicating that a Mobility Event (ME) associated with the second cell is to be performed. At block 930, the WTRUs 102, 200, 300, 400, and 500 may perform a first PRS measurement on one or more transmissions from a first cell using a PRS configuration and an MG configuration. For example, execution of PRS measurements may occur before and after execution of the indicated ME.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following: (1) Transmitting a request to the first cell, the request including preference information indicating that MG configuration is maintained after execution of an ME associated with the second cell; and/or (2) receiving acknowledgement information indicating that the following is acknowledged: (i) The ME associated with the second cell will be executed, and (ii) the MG configuration is maintained after execution of the ME.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following: (1) After performing the ME, performing a second PRS measurement on a first transmission or further transmission from the first cell using the first PRS configuration and the MG configuration; and/or (2) send information indicative of the second PRS measurements to a Network Entity (NE) of the second cell.

Fig. 10 is a flowchart illustrating yet another representative method implemented by a WTRU.

Referring to fig. 10, the exemplary method 1000 may include, at block 1010, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information indicating: (1) One or more sounding reference signal (SRSp) configurations for positioning and (2) one or more validity conditions. At block 1020, the WTRUs 102, 200, 300, 400, and 500 may select the indicated SRSp configuration if one or more indicated validity conditions associated with the indicated SRSp configuration are met. At block 1030, the WTRUs 102, 200, 300, 400, and 500 may send an uplink transmission including one or more srsps to a Network Entity (NE) according to the selected SRSp configuration.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may receive location information associated with the WTRUs 102, 200, 300, 400, and 500 from the NE. For example, the positioning information may be derived from SRSp measurements of uplink transmissions.

In certain representative embodiments, each SRSp configuration may be associated with a set of indicated validity conditions including any one of: (1) one or more zone-related conditions; (2) One or more time-related conditions and/or (3) one or more mobility-related attribute conditions. For example, the one or more zone-related conditions may include any of the following: (1) The detected cell identifiers associated with coverage areas of cells for serving WTRUs 102, 200, 300, 400, and 500 correspond to the cell identifiers associated with the respective SRSp configurations; (2) The detected Radio Access Network (RAN) notification areas of WTRUs 102, 200, 300, 400, and 500 correspond to RAN notification areas associated with respective SRSp configurations; (3) The detected geographic areas of the WTRUs 102, 200, 300, 400, and 500 correspond to the geographic areas associated with the respective SRSp configurations; (4) The determined area identifiers of WTRUs 102, 200, 300, 400, and 500 correspond to the area identifiers associated with the respective srsps. The detected cell identifier may correspond to a cell identifier associated with a respective SRSp configuration.

As a second example, the one or more time-related conditions may include any of the following: (1) A time during a time period after the trigger condition is satisfied; (2) A time (e.g., a time stamp) after the end of the period of time from when the trigger condition is satisfied; and/or (3) a time during a time window after the trigger condition is satisfied.

As a third example, the one or more mobility-related attribute conditions may include any of the following: (1) The detected speeds or rates of the WTRUs 102, 200, 300, 400, and 500 satisfy the speed or rate conditions associated with the respective SRSp configurations; (2) The determined speed or rate of change of the WTRUs 102, 200, 300, 400, and 500 satisfies the speed or rate of change condition associated with the corresponding SRSp configuration; (3) The expected speeds or rates of the WTRUs 102, 200, 300, 400, and 500 satisfy the speed or rate conditions associated with the corresponding SRSp configuration; (4) The expected speed or rate of change of the WTRUs 102, 200, 300, 400, and 500 satisfies the speed or rate of change condition associated with the corresponding SRSp configuration; (5) The detected direction of movement of the WTRUs 102, 200, 300, 400, and 500 satisfies the direction of movement condition associated with the respective SRSp configuration; (6) The expected directions of movement of the WTRUs 102, 200, 300, 400, and 500 satisfy the direction of movement conditions associated with the respective SRSp configuration; (7) The detected orientations of WTRUs 102, 200, 300, 400, and 500 satisfy the orientation conditions associated with the respective SRSp configurations; (8) The expected orientations of WTRUs 102, 200, 300, 400, and 500 satisfy the orientation conditions associated with the respective SRSp configurations; (9) The determined environmental states experienced by the WTRUs 102, 200, 300, 400, and 500 satisfy the environmental conditions associated with the respective SRSp configurations; (10) The expected environmental states that the WTRUs 102, 200, 300, 400, and 500 will experience satisfy the environmental conditions associated with the respective SRSp configurations; (11) The determined indoor/outdoor status of the WTRUs 102, 200, 300, 400, and 500 satisfies the indoor/outdoor conditions associated with the respective SRSp configuration; and/or (12) the expected indoor/outdoor status of the WTRUs 102, 200, 300, 400, and 500 satisfies the indoor/outdoor status conditions associated with the corresponding SRSp configuration.

Fig. 11 is a flow chart illustrating a further exemplary method implemented by a WTRU.

Referring to fig. 11, an exemplary method 1100 may include, at block 1110, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information associated with: (1) a first positioning operation, (2) a second positioning operation, and (3) one or more trigger conditions for starting and/or stopping use of the second positioning operation. At block 1120, the WTRUs 102, 200, 300, 400, and 500 may perform any of a first PRS measurement and/or a first SRSp transmission with a Network Entity (NE) associated with a first cell using a first configuration associated with a first positioning operation. At block 1130, the WTRUs 102, 200, 300, 400, and 500 may be configured to: (1) Initiating use of a second positioning operation, and (2) performing any of a second PRS measurement and/or a second SRSp transmission using a second configuration associated with the second positioning operation.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may trigger, after initiating the second positioning operation, to perform a second PRS measurement during a Mobility Event (ME) using a second configuration associated with the second positioning operation; synchronizing the WTRUs 102, 200, 300, 400, and 500 with the second cell; and performing further PRS measurements using further configurations after the WTRUs 102, 200, 300, 400, and 500 are synchronized with the second cell. In some embodiments, the execution of the first PRS measurements may use a first configuration before executing the ME.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may trigger, after initiating the second positioning operation, to perform a second SRSp transmission during a Mobility Event (ME) using a second configuration associated with the second positioning operation; synchronizing the WTRUs 102, 200, 300, 400, and 500 with a first NE associated with a second cell; and performing further SRSp transmissions using the further configuration after the WTRU synchronizes with the second cell. In some embodiments, execution of the first SRSp transmission may use the first configuration prior to execution of the ME. For example, the second positioning operation may correspond to a relaxed or stricter synchronization timing requirement relative to the first positioning operation.

In certain representative embodiments, the first positioning operation may comprise any one of the following operations: (1) downlink time difference of arrival operation; (2) uplink SRSp operation; (3) Multiple round trip time (multiple RTTs) operation and/or (4) downlink PRS operation. The second positioning operation may include any of the following different operations: (1) downlink time difference of arrival operation; (2) uplink SRSp operation; (3) multi-RTT operation and/or (4) downlink PRS operation.

In some representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may send information to a Network Entity (NE) indicating any of the following: (1) a second measurement; (2) timing information; (3) A timestamp indicating when the WTRU switched from using the first PRS configuration to the second PRS configuration; (4) a time difference between the received PRS and the transmitted SRSp; and/or (5) the measured RSRP of PRS.

Fig. 12 is a flow chart illustrating another additional representative method implemented by a WTRU (e.g., to support location service continuity).

Referring to fig. 12, the representative method 1200 may include, at block 1210, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information indicating at least: (1) A plurality of PRS configurations including a first PRS configuration associated with a first cell or a first base station and a second PRS configuration associated with a second cell, and (2) a first RAN configuration. At block 1220, the WTRU 102, 200, 300, 400, and 500 may perform PRS measurements using the indicated first PRS configuration and the indicated first RAN configuration on a condition that the WTRU 102, 200, 300, 400, and 500 is in a coverage area of a first cell or a first base station. At block 1230, the WTRUs 102, 200, 300, 400, and 500 may determine to initiate use of the second PRS configuration based on PRS measurements. At block 1240, the WTRUs 102, 200, 300, 400, and 500 may determine a second RAN configuration associated with the second PRS configuration from the received configuration information. At block 1250, the WTRUs 102, 200, 300, 400, and 500 may initiate performing PRS measurements using the second PRS configuration and the second RAN configuration.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform any of the following: (1) Transmitting information indicating the determined second RAN configuration to a serving base station as the first base station; and/or (2) receiving information from the serving base station confirming use or activation of the second RAN configuration.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may trigger the execution of PRS measurements based on a Mobility Event (ME). For example, the performing of PRS measurements may use a first PRS configuration and a first RAN configuration (1) prior to the ME and/or (2) during at least a first portion of the ME. In some embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform PRS measurements (1) during at least a second portion of the ME and/or (2) after the ME using a second PRS configuration and a second RAN configuration.

Fig. 13 is a flow chart illustrating yet another representative method implemented by a WTRU (e.g., to support location service continuity).

Referring to fig. 13, the exemplary method 1300 may include, at block 1310, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information associated with: (1) a first positioning operation, (2) a second positioning operation, and (3) one or more trigger conditions for starting and/or stopping use of the second positioning operation. At block 1320, the WTRUs 102, 200, 300, 400, and 500 may perform any of PRS measurements and/or SRSp transmissions using a first PRS configuration associated with a first positioning operation. At block 1330, the WTRUs 102, 200, 300, 400, and 500 may, if a trigger condition is met to begin using the second positioning operation: (1) Initiate use of a second positioning operation, and/or (2) perform any of PRS measurements and/or SRSp transmissions using a second PRS configuration associated with the second positioning operation.

In certain representative embodiments, the WTRUs 102, 200, 300, 400, and 500 may perform PRS measurements and/or SRSp transmissions using a second PRS configuration associated with a second positioning operation based on a Mobility Event (ME) trigger. For example, the execution of PRS measurements may use a first PRS configuration (1) before the ME and/or (2) during at least a first portion of the ME. As another example, the performing of PRS measurements may use a second PRS configuration (1) during at least a second portion of the ME and/or (2) after the ME.

Figure 14 is a flow chart illustrating a further representative method implemented by a WTRU (e.g., to support location service continuity).

Referring to fig. 14, the representative method 1400 may include, at block 1410, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information indicating: (1) One or more PRS configurations and (2) one or more zone availability conditions. At block 1420, the WTRUs 102, 200, 300, 400, and 500 may select one of the indicated PRS configurations that matches at least one of the detected cells on the condition that one or more cells with a cell ID indicated by a region validity condition are detected. At block 1430, the WTRU 102, 200, 300, 400, and 500 may send information to the network entity indicating the cell ID of the at least one detected cell and the selected PRS configuration. At block 1440, the WTRUs 102, 200, 300, 400, and 500 may perform PRS measurements using the selected PRS configuration.

Fig. 15 is a flow chart illustrating yet another additional exemplary method implemented by a WTRU.

Referring to fig. 15, an exemplary method 1500 may include, at block 1510, the WTRUs 102, 200, 300, 400, and 500 receiving configuration information indicating at least: (1) a first PRS configuration and a second PRS configuration; (2) A first set of thresholds associated with a first PRS configuration and (3) a second set of thresholds associated with a second PRS configuration. At block 1520, the WTRUs 102, 200, 300, 400, and 500 may perform a handover from the first base station to the second base station. For example, the indicated first PRS configuration associated with the first base station and the indicated first set of thresholds associated with the indicated first PRS configuration may be active during a handover. At block 1530, the WTRUs 102, 200, 300, 400, and 500 may switch from the active first PRS configuration associated with the first base station and the first set of thresholds associated with the indicated first PRS configuration to the indicated second PRS configuration associated with the second base station as a new active PRS configuration and to the indicated second set of thresholds associated with the indicated second PRS configuration as a new active threshold set after the switch.

Conclusion(s)

Although the features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with other features and elements. Additionally, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer readable medium for execution by a computer or processor. Examples of non-transitory computer readable storage media include, but are not limited to, read-only memory (ROM), random-access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks and Digital Versatile Disks (DVDs). A processor associated with the software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Furthermore, in the above embodiments, processing platforms, computing systems, controllers, and other devices including processors are indicated. These devices may include at least one central processing unit ("CPU") and memory. References to actions and symbolic representations of operations or instructions may be performed by various CPUs and memories in accordance with practices of persons skilled in the art of computer programming. Such acts and operations, or instructions, may be considered to be "executing," computer-executed, "or" CPU-executed.

Those of ordinary skill in the art will appreciate that the acts and symbolically represented operations or instructions include the manipulation of electrical signals by the CPU. The electrical system represents data bits that may result in a final transformation of the electrical signal or a reduction of the electrical signal and a retention of the data bits at memory locations in the memory system, thereby reconfiguring or otherwise altering the operation of the CPU and performing other processing of the signal. The memory location holding the data bit is a physical location having a particular electrical, magnetic, optical, or organic attribute corresponding to or representing the data bit. It should be understood that the exemplary embodiments are not limited to the above-described platforms or CPUs, and that other platforms and CPUs may also support the provided methods.

The data bits may also be maintained on computer readable media including magnetic disks, optical disks, and any other volatile (e.g., random access memory ("RAM")) or non-volatile (e.g., read only memory ("ROM")) mass storage system readable by the CPU. The computer readable media may comprise cooperating or interconnected computer readable media that reside exclusively on the processing system or are distributed among a plurality of interconnected processing systems, which may be local or remote relative to the processing system. It should be understood that the representative embodiments are not limited to the above-described memories, and that other platforms and memories may support the described methods.

In an exemplary embodiment, any of the operations, processes, etc. described herein may be implemented as computer readable instructions stored on a computer readable medium. The computer readable instructions may be executed by a processor of the mobile unit, the network element, and/or any other computing device.

There is little distinction between hardware implementations and software implementations of aspects of the system. The use of hardware or software is often (but not always, as in some contexts the choice between hardware and software may become important) a design choice representing a tradeoff between cost and efficiency. There may be various media (e.g., hardware, software, and/or firmware) that may implement the processes and/or systems and/or other techniques described herein, and the preferred media may vary with the context in which the processes and/or systems and/or other techniques are deployed. For example, if the implementer determines that speed and accuracy are paramount, the implementer may opt for a medium of mainly hardware and/or firmware. If flexibility is paramount, the implementer may opt for a particular implementation of mainly software. Alternatively, the implementer may opt for some combination of hardware, software, and/or firmware.

The foregoing detailed description has set forth various embodiments of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples. Where such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those skilled in the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a Digital Signal Processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), field Programmable Gate Arrays (FPGAs) circuits, any other type of Integrated Circuit (IC), and/or a state machine.

The present disclosure is not limited to the specific embodiments described in this patent application, which are intended as illustrations of various aspects. Many modifications and variations may be made without departing from the spirit and scope of the invention, as will be apparent to those skilled in the art.

Functionally equivalent methods and apparatus, other than those enumerated herein, which are within the scope of the present disclosure, will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It should be understood that the present disclosure is not limited to a particular method or system.

It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the terms "station" and its abbreviation "STA", "user equipment" and its abbreviation "UE" may mean, as referred to herein: (i) A wireless transmit and/or receive unit (WTRU), such as described below; (ii) Any of several embodiments of the WTRU, such as those described below; (iii) Devices with wireless capabilities and/or with wired capabilities (e.g., tethered) are configured with some or all of the structure and functionality of a WTRU, in particular, such as described below; (iii) A wireless-capable and/or wireline-capable device may be configured with less than all of the structure and functionality of a WTRU, such as described below; or (iv) etc. Details of an exemplary WTRU, which may represent any of the WTRUs described herein, are provided below with respect to fig. 1A-1D, fig. 2, and fig. 3.

In certain implementations, portions of the subject matter described herein can be implemented via an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP), and/or other integrated format. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and/or firmware would be well within the skill of one of skill in the art in light of this disclosure. Furthermore, those skilled in the art will appreciate that the mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative embodiment of the subject matter described herein applies regardless of the particular type of signal bearing media used to actually carry out the distribution. Examples of signal bearing media include, but are not limited to, the following: recordable type media (such as floppy disks, hard disk drives, CDs, DVDs, digital tapes, computer memory, etc.); and transmission type media such as digital and/or analog communications media (e.g., fiber optic cable, waveguide, wired communications link, wireless communications link, etc.).

The subject matter described herein sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Thus, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected," or "operably coupled," to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable," to each other to achieve the desired functionality. Specific examples of operably couplable include, but are not limited to, physically mateable and/or physically interactable components and/or wirelessly interactable components and/or logically interactable components.

With respect to substantially any plural and/or singular terms used herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. For clarity, various singular/plural permutations may be explicitly listed herein.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "comprising" should be interpreted as "including but not limited to," etc.). It will be further understood by those with skill in the art that if a specific number of an introduced claim recitation is intended, such intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, where only one item is contemplated, the term "single" or similar language may be used. To facilitate understanding, the following appended claims and/or the description herein may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation object by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation object to embodiments containing only one such recitation object. Even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should be interpreted to mean "at least one" or "one or more"). The same holds true for the use of definite articles used to introduce claim recitations. Furthermore, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations). In addition, in those instances where a convention analogous to "at least one of A, B and C, etc." is used, in general such a construction has the meaning that one having skill in the art would understand the convention (e.g., "a system having at least one of A, B and C" would include but not be limited to systems that have a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B and C together, etc.). In those instances where a convention analogous to "at least one of A, B or C, etc." is used, in general such a construction has the meaning that one having skill in the art would understand the convention (e.g., "a system having at least one of A, B or C" would include but not be limited to systems having a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B and C together, etc.). It should also be understood by those within the art that virtually any separate word and/or phrase presenting two or more alternative terms, whether in the specification, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "a or B" will be understood to include the possibilities of "a" or "B" or "a and B". In addition, as used herein, the term "…" followed by listing a plurality of items and/or a plurality of item categories is intended to include items and/or item categories "any one of", "any combination of", "any multiple of" and/or any combination of multiples of "alone or in combination with other items and/or other item categories. Furthermore, as used herein, the term "group" or "group" is intended to include any number of items, including zero. Furthermore, as used herein, the term "number" is intended to include any number, including zero.

Further, where features or aspects of the present disclosure are described in terms of markush groups, those skilled in the art will recognize thereby that the present disclosure is also described in terms of any individual member or subgroup of members of the markush group.

As will be understood by those skilled in the art, for any and all purposes (such as in terms of providing a written description), all ranges disclosed herein also encompass any and all possible sub-ranges and combinations of sub-ranges thereof. Any listed range can be readily identified as sufficiently descriptive and so that the same range can be divided into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily divided into a lower third, a middle third, an upper third, and the like. As will also be understood by those skilled in the art, all language such as "up to", "at least", "greater than", "less than", etc., include the recited numbers and refer to ranges that may be subsequently divided into sub-ranges as described above. Finally, as will be understood by those skilled in the art, the scope includes each individual number. Thus, for example, a group having 1 to 3 units refers to a group having 1, 2, or 3 units. Similarly, a group having 1 to 5 units refers to a group having 1, 2, 3, 4, or 5 units, or the like.

Furthermore, the claims should not be read as limited to the order or elements provided, unless stated to that effect. Furthermore, use of the term "means for … …" in any claim is intended to invoke 35 U.S. C. ≡112,6 or device plus function claims format, and any claims without the term "device for … …" are not intended to be so.

Throughout this disclosure, those skilled in the art will appreciate that certain representative embodiments can be used in alternative forms or in combination with other representative embodiments.

No element, act, or instruction used in the description of the present application should be construed as critical or essential to the application unless explicitly described as such. In addition, as used herein, the article "a" is intended to include one or more items. Where only one item is contemplated, the term "a" or similar language is used. In addition, as used herein, the term "… …" followed by listing a plurality of items and/or a plurality of item categories is intended to include items and/or item categories "any one of", "any combination of", "any multiple of" and/or any combination of multiples of "alone or in combination with other items and/or other item categories. Furthermore, as used herein, the term "group" is intended to include any number of items, including zero. In addition, as used herein, the term "number" is intended to include any number, including zero.

Furthermore, the claims should not be read as limited to the described order or elements unless stated to that effect. In addition, use of the term "apparatus" in any claim is intended to invoke 35 U.S. C. ≡112,any claims that do not have the term "means" are not intended to so.

Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a Digital Signal Processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, application Specific Integrated Circuits (ASICs), application Specific Standard Products (ASSPs), field Programmable Gate Arrays (FPGAs) circuits, any other type of Integrated Circuit (IC), and/or a state machine.

A processor associated with the software may be used to implement the use of a radio frequency transceiver in a Wireless Transmit Receive Unit (WTRU), a User Equipment (UE), a terminal, a base station, a Mobility Management Entity (MME) or an Evolved Packet Core (EPC) or any host computer. The WTRU may be used in combination with a module, and may be implemented in hardware and/or software including: software Defined Radio (SDR) and other components such as cameras, video camera modules, video phones, speakerphones, vibration devices, speakers, microphones, television transceivers, hands-free headsets, keyboards, and the like, Module, frequency Modulation (FM) radio unit, near Field Communication (NFC) module, liquid Crystal Display (LCD) display unit, organic Light Emitting Diode (OLED) display unit, digital music player,A media player, a video game player module, an internet browser, and/or any Wireless Local Area Network (WLAN) or Ultra Wideband (UWB) module.

Although the present invention has been described in terms of a communication system, it is contemplated that the system may be implemented in software on a microprocessor/general purpose computer (not shown). In some embodiments, one or more of the functions of the various components may be implemented in software that controls a general purpose computer.

In addition, while the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.

Claims (19)

1. A method implemented by a wireless transmit/receive unit (WTRU), the method comprising:

receiving information indicating: (1) a first Positioning Reference Signal (PRS) configuration associated with a first cell, (2) a second PRS configuration associated with a second cell, and (3) a Measurement Gap (MG) configuration;

Performing a first PRS measurement on a first transmission from the first cell using the first PRS configuration and the MG configuration;

transmitting a request to a first Network Entity (NE) associated with the first cell, the request comprising information indicating to maintain the MG configuration after performing a Mobility Event (ME) associated with the second cell;

receiving information indicating: (1) Executing the ME associated with the second cell, and (2) maintaining the MG configuration after executing the ME;

after performing the ME, performing a second PRS measurement on the first transmission or further transmission from the first cell using the first PRS configuration and the MG configuration; and

information indicating the second PRS measurements is sent to a second NE associated with the first cell.

2. The method of claim 1, further comprising determining to send the request to the first cell indicating that the MG configuration is maintained after the ME is executed.

3. The method of any of claims 1-2, wherein the first NE associated with the first cell and the second NE associated with the first cell are one base station or the first NE is a first base station and the second NE is a Location Management Function (LMF) entity.

4. The method of any of claims 1 to 3, wherein on condition that the second PRS measurement does not meet a PRS ME threshold:

sending a request for further MG configuration to a first NE associated with the second cell;

receiving information indicating the further MG configuration;

performing a third PRS measurement on transmissions from the second cell using the second PRS configuration and the further MG configuration; and

transmitting further information to a second NE associated with the second cell indicating any of: (1) the third PRS measurement, (2) the second PRS configuration, and/or (3) a time when the WTRU starts to use the second PRS configuration.

5. The method according to claim 4, wherein:

the first NE associated with the first cell and the second NE associated with the first cell are a single base station, or the first NE associated with the first cell is a first base station and the second NE associated with the first cell is a Location Management Function (LMF) entity; and is also provided with

The first NE associated with the second cell and the second NE associated with the second cell are another single base station, or the first NE associated with the second cell is a second base station and the second NE associated with the second cell is the Location Management Function (LMF) entity.

6. The method of any one of claims 1 to 5, wherein:

the ME is any one of the following: (1) switching; or (2) reselecting; and is also provided with

The method includes performing the handover or the reselection of the WTRU to the second cell.

7. The method of any one of claims 4, wherein:

the further information is included in a location services continuity report; and is also provided with

The method includes receiving a new PRS configuration or an updated PRS configuration in response to the positioning service continuity report, wherein the new PRS configuration or the updated PRS configuration is associated with a target NE or the first NE associated with the second cell.

8. The method of any of claims 1-7, wherein performing a second PRS measurement on the first transmission or the further transmission from the first cell using the first PRS configuration and the MG configuration after performing the ME comprises performing the first PRS measurement on the first transmission from the first cell using the first PRS configuration associated with the first cell in a coverage area of the second cell after a data link handover.

9. The method of any of claims 1-8, further comprising performing further PRS measurements on transmissions from the second cell in a coverage area of the first cell using the second PRS configuration associated with the second cell prior to performing the ME.

10. The method of any of claims 1 to 9, further comprising, during the ME, (1) performing further PRS measurements on the transmissions from the first cell using the first PRS configuration of the first cell, and (2) performing further PRS measurements on transmissions from the second cell using the second PRS configuration of the second cell.

11. The method of any of claims 1 to 10, further comprising switching from a first positioning method to a second positioning method during the ME.

12. The method of any of claims 1-11, further comprising receiving, by the WTRU, information indicating to use, activate, or deactivate one or more of the PRS configurations.

13. The method of any one of claims 1 to 12, the method further comprising:

triggering execution of the second PRS measurement in response to the ME,

Wherein:

(1) The performing of the first PRS measurement uses the first PRS configuration and the MG configuration prior to performing the ME, and (2) the performing of the second PRS measurement uses the first PRS configuration and the MG configuration during at least a first portion of the ME,

the method includes performing further PRS measurements using the second PRS configuration and the second MG configuration (1) during at least a second portion of the ME and (2) after performing the ME.

14. The method according to any one of claims 1 to 13, the method comprising:

receiving, by the WTRU, information associated with: (1) a first positioning operation, (2) a second positioning operation, and (3) one or more trigger conditions for starting and/or stopping use of the second positioning operation; and

initiating use of the second positioning operation on condition that the one or more trigger conditions are met to begin use of the second positioning operation,

wherein:

execution of the first PRS measurements uses the first PRS configuration associated with the first positioning operation and

execution of the second PRS measurements uses the second PRS configuration associated with the second positioning operation.

15. The method of claim 14, the method further comprising:

in response to the ME, triggering the use of the second PRS configuration associated with the second positioning operation to perform the second PRS measurement,

wherein:

(1) Prior to executing the ME and (2) during at least a first portion of the ME, execution of the first PRS measurements uses the first PRS configuration,

(1) The performing of the second PRS measurements uses the second PRS configuration during at least a second portion of the ME and (2) after the ME is performed.

16. The method of any one of claims 1 to 15, the method further comprising:

receiving, by the WTRU, report configuration information indicating a plurality of report configurations, wherein each of the indicated report configurations is associated with a trigger condition type associated with the ME; and

a location report is sent to a Location Management Function (LMF) entity according to the trigger condition type associated with the ME.

17. The method of claim 16, wherein the trigger condition type associated with the ME comprises any one of: (1) a speed related trigger condition associated with the WTRU; (2) a rate related trigger condition associated with the WTRU; (3) A movement direction related trigger condition associated with the WTRU; (4) an orientation related trigger condition associated with the WTRU; (5) an environment-related trigger condition associated with the WTRU; (6) An indoor/outdoor status related trigger condition associated with the WTRU; and/or

(7) The neighboring cells detect/discover related trigger conditions.

18. The method of claim 16, wherein a first reporting configuration of the indicated plurality of reporting configurations includes first periodicity information and a second reporting configuration of the indicated plurality of reporting configurations includes second, different periodicity information.

19. A wireless transmit/receive unit (WTRU) comprising a processor, transceiver, and memory configured to perform the method of any one of claims 1 to 18.