Methods, apparatuses and systems directed to idle / inactive mode positioning in nr

Abstract

To provide methods, apparatuses and systems for performing positioning of a wireless transmit / receive unit (WTRU) while the WTRU is in an idle mode and / or inactive mode.SOLUTION: In a method in a communication system for performing positioning including reporting in an idle / inactive mode thereby allowing increased positioning accuracy and decreased latency of location determination, a WTRU in an idle / inactive mode is configured to: transmit a positioning measurement report in various ways, including report transmission in a random-access channel (RACH) preamble, as an appendage to a RACH preamble, and / or in a physical uplink shared channel; transmit uplink-based positioning related reference signals; and transmit, e.g., downlink positioning measurement reports and / or reference signals (RSs) for uplink positioning measurements, over a dedicated physical channel.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present disclosure relates to network communications, including but not limited to methods, devices, systems, etc., aimed at performing positioning in idle and / or inactive modes in NR. [Background technology]

[0002] Positioning may enable the geographic location (position) of a mobile terminal to be determined. The location may be used to support Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network (E-UTRAN) functions, such as radio resource management. The location may also be used to support location-based services and / or applications, for example, for operators, subscribers, and third-party service providers. Examples of these services and applications include support for emergency calling, such as Internet Protocol Multimedia Subsystem (IMS) emergency calling over the Evolved Packet System (EPS), or supporting compliance with the Federal Communications Commission's (FCC) E-911 regulatory requirements, entitled "FCC Fourth Report and Order: Wireless E911 Location Accuracy Requirements." Other examples of services and applications using positioning include Google Maps, targeted advertising, and the like. Summary of the Invention

[0003] Disclosed herein are methods, apparatus, systems, etc. directed to performing positioning in idle and / or inactive modes (collectively, “idle / inactive modes”) in NR. In one embodiment, a wireless transmit / receive unit (WTRU) may perform positioning measurements in idle / inactive mode. In one embodiment, the WTRU may perform positioning measurements (e.g., downlink) and reporting in idle / inactive mode. Performing positioning measurements and reporting in idle / inactive mode may enable increased positioning accuracy and / or reduced latency of location determination. In one embodiment, the WTRU may transmit positioning measurement reports in a random access channel (RACH) preamble in idle / inactive mode. In one embodiment, the WTRU may transmit positioning measurement reports appended to the RACH preamble in idle / inactive mode. In one embodiment, the WTRU may transmit positioning measurement reports in a physical uplink shared channel (PUSCH) in idle / inactive mode. In one embodiment, the WTRU may be configured to transmit uplink-based positioning-related reference signals in idle / inactive mode. In one embodiment, the WTRU may be configured to transmit (e.g., downlink) positioning measurement reports and / or reference signals (RS) for uplink positioning measurements over a dedicated (e.g., new) physical channel while running in an idle / inactive mode.

[0004] Although various embodiments are described and / or claimed herein in which apparatus, systems, devices, etc. and / or any elements thereof are configured to perform operations, processes, algorithms, functions, etc. and / or any portions thereof, it is understood that any embodiment described and / or claimed herein presupposes that any apparatus, system, device, etc. and / or any elements thereof performs any operation, process, algorithm, function, etc. and / or any portion thereof (and vice versa). [Brief description of the drawings]

[0005] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, in which: Figures in such drawings, like the detailed description, are examples; thus, the figures and detailed description are not to be considered limiting, as other equally effective examples are possible and possible. Moreover, like reference numerals in the figures indicate like elements.

[0006] [Figure 1A] FIG. 1 is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented. [Figure 1B] 1A is a system diagram illustrating an example of a wireless transmit / receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A, according to one embodiment. [Figure 1C] 1B is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1A, according to one embodiment. [Figure 1D] FIG. 1B is a system diagram illustrating a further exemplary RAN and a further exemplary CN that can be used within the communication system illustrated in FIG. 1A, according to one embodiment. [Diagram 2] FIG. 1 is a system diagram illustrating an example of positioning based on Observed Time Difference of Arrival. [Diagram 3] FIG. 1 illustrates an example of idle / inactive mode positioning measurements. [Figure 4] A diagram showing an example of a signaling exchange for idle / inactive mode positioning measurements. [Diagram 5] FIG. 13 is a diagram showing an example of a one-message positioning report using a RACH preamble. [Figure 6] A diagram showing an example of a signaling exchange for preamble-based positioning measurement reporting. [Figure 7] FIG. 13 shows an example of a one-message downlink positioning measurement report with a report added to the PRACH preamble. [Figure 8]A diagram showing an example of a signaling exchange for idle / inactive mode positioning measurement reporting with reports appended to the RACH preamble. [Figure 9] FIG. 13 is a diagram showing an example of a two-message downlink positioning measurement report using PRACH and PUSCH. [Figure 10] FIG. 13 shows an example of a signaling exchange for two-message idle / inactive mode positioning measurement reporting using PRACH and PUSCH. [Figure 11] FIG. 1 illustrates an example of an uplink-based positioning update procedure. [Figure 12] FIG. 1 illustrates an example of uplink-based idle / inactive mode positioning using a common positioning-specific preamble. [Figure 13A] 1 illustrates an example of a first part of a signaling exchange for uplink-based idle / inactive mode positioning using a common positioning-specific preamble with contention resolution. [Figure 13B] FIG. 13B illustrates an example of a second portion of the signaling exchange of FIG. 13A. [Figure 14] 1 illustrates an example of a positioning preamble selection by a WTRU. [Figure 15] FIG. 13 is a diagram illustrating an example of a positioning report transmission. [Figure 16] FIG. 1 illustrates an example of idle / inactive mode positioning measurements. [Figure 17-18] 2A-2C are two diagrams showing two examples of positioning measurement reports in idle / inactive mode; [Figure 19-20] 2A-2C are two diagrams showing two examples of uplink-based positioning; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] A detailed description of exemplary embodiments will now be described with reference to various figures. While this description provides detailed examples of possible implementations, it should be noted that the details are for illustrative purposes and do not limit the scope of application. In the following detailed description, numerous specific details are described to provide a thorough understanding of the embodiments and / or examples described herein. However, it will be understood that such embodiments and examples may be practiced without some or all of the specific details described herein. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the following description. Furthermore, embodiments and examples not specifically described herein may be practiced in place of or in combination with the embodiments and other examples provided herein, as described, disclosed, or otherwise explicitly, implicitly, and / or inherently (collectively "provided")

[0008] Exemplary Communication Network 1A illustrates an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multi-access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources, including wireless bandwidth. For example, the communication system 100 may employ one or more channel access schemes, 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-Tailed Unique Word DFT-Spread OFDM (ZT UW DTS-s OFDM), Unique Word OFDM (UW-OFDM), Resource Block Filtered OFDM, Filter Bank Multi-Carrier (FBMC), etc.

[0009] 1A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a RAN 104 / 113, a CN 106 / 115, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, although it will 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. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a “station” and / or “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, mobile phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (IoT) devices, watches or other wearables, head mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronics devices, device networks operating with commercial and / or industrial wireless, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be referred to interchangeably as a UE.

[0010] The communication system 100 may also include a base station 114a and / or a 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 other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode-B, a home Node-B, a home eNode-B, a gNB, an NR Node-B, a site controller, an access point (AP), a wireless router, etc. Although the base stations 114a, 114b are each shown as a single element, it will be understood that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0011] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and / or the 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 a cell (not shown). These frequencies may be licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide wireless service coverage to a particular geographic area that may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In one embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming can be used to transmit and / or receive signals in a desired spatial direction.

[0012] The base stations 114a, 114b may communicate with one or more 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, microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0013] More specifically, as noted above, the 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, etc. For example, the base stations 114a and the WTRUs 102a, 102b, 102c of the RAN 104 / 113 may implement a radio technology, such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115 / 116 / 117 using Wideband CDMA (WCDMA). 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 ​​UL Packet Access (HSUPA).

[0014] In one 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 establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0015] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using New Radio (NR).

[0016] In one embodiment, 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 and from multiple types of base stations (e.g., eNBs and gNBs).

[0017] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement a wireless technology such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Global Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE (GERAN), or the like.

[0018] The base station 114b of FIG. 1A may be, for example, a wireless router, a Home Node-B, a Home eNode-B, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, etc. In one 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 one 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 picocell or femtocell. 1A, the base station 114b may be directly connected to the Internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106 / 115.

[0019] The RAN 104 / 113 may communicate with the CN 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 WTRUs 102a, 102b, 102c, 102d. The data may have various Quality of Service (QoS) requirements, such as different throughput requirements, delay requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, charging services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high level security functions, such as user authentication. Although not shown in FIG. 1A, it will be understood that the RAN 104 / 113 and / or the CN 106 / 115 may communicate directly or indirectly with other RANs that use the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also communicate with another RAN (not shown) that uses GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0020] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network providing plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and / or Internet Protocol (IP) of the TCP / IP Internet protocol suite. The 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 use the same RAT as the RANs 104 / 113 or a different RAT.

[0021] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications 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 wireless technology, and with a base station 114b, which may employ an IEEE 802 wireless technology.

[0022] 1B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1B, the WTRU 102 may include, among other things, 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 peripherals 138. It will be understood that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment.

[0023] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC) thereof, a state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other function that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although FIG. 1B depicts the processor 118 and the transceiver 120 as separate components, it will be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0024] The transmit / receive element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) 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 transmit and / or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0025] 1B as a single element, 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.

[0026] The transceiver 120 may be configured to modulate signals transmitted by the transmit / receive element 122 and demodulate signals received by the transmit / receive element 122. As mentioned above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0027] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128 (e.g., 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. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as non-removable memory 130 and / or 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. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, or the like. In other embodiments, the processor 118 may access information from and store data in memory that is not physically located on the WTRU 102, such as a server or home computer (not shown).

[0028] The processor 118 may receive power from the power source 134 and may be configured to distribute and / or control the power to other components within the WTRU 102. The power source 134 may be any suitable device for providing power to the WTRU 102. For example, the power source 134 may include one or more dry batteries (e.g., nickel cadmium (NiCd), nickel zinc (NiZn), nickel metal hydride (NiMH), lithium ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0029] 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 instead of information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or may determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may obtain location information by way of any suitable location determination method while remaining consistent with an embodiment.

[0030] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photos and / or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, and / or the like. The peripherals 138 may include one or more sensors, which may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, a direction sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0031] The WTRU 102 may include a full-duplex radio in which transmission and reception of some or all of the signals (e.g., associated with a particular subframe) on both the UL (e.g., for transmission) and downlink (e.g., for reception) may occur in parallel and / or simultaneously. The full-duplex radio may include an interference management unit 139 to reduce and / or substantially eliminate self-interference either via hardware (e.g., chokes) or a processor (e.g., signal processing via a separate processor (not shown) or processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for transmission and reception of some or all of the signals (e.g., associated with a particular subframe on either the UL (e.g., for transmission) or downlink (e.g., for reception)).

[0032] 1C is a system diagram illustrating the RAN 104 and the CN 106 according to one embodiment. As mentioned above, the RAN 104 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 using E-UTRA radio technology. The RAN 104 may also communicate with the CN 106.

[0033] The RAN 104 may include eNode-Bs 160a, 160b, 160c, although it will be understood that the 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 for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a may, for example, use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0034] Each of the eNode-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 the UL and / or DL, etc. As shown in FIG 1C, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0035] 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 is shown as part of the CN 106, it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0036] The MME 162 may be connected to each of the eNode-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 users of the WTRUs 102a, 102b, 102c, activating / deactivating bearers, selecting a particular serving gateway during initial attachment of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that use other radio technologies, such as GSM and / or WCDMA.

[0037] The SGW 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to and from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as fixing the user plane during inter-eNode-B handovers, triggering paging when DL data is available to the WTRUs 102a, 102b, 102c, managing and storing context for the WTRUs 102a, 102b, 102c, etc.

[0038] The SGW 164 may be connected to a PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0039] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional landline communications devices. For example, the CN 106 may include or 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.

[0040] Although the WTRU is depicted in FIGS. 1A-1D as a wireless terminal, in certain representative embodiments it is contemplated that such a terminal may use a wired communications interface (e.g., temporarily or permanently) with the communications network.

[0041] In an exemplary embodiment, the other network 112 may be a WLAN.

[0042] A WLAN in 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 into and / or out of the BSS. Traffic to the STA originating from outside the BSS may arrive through the AP and be delivered to the STA. Traffic originating from the STA to a destination outside the BSS may be sent to the AP and delivered to the respective destination. Traffic between STAs in the BSS may be transmitted through the AP. For example, a source STA may transmit traffic to the AP, and the AP may deliver the traffic to the destination STA. Traffic between STAs in the BSS may be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic may be transmitted (e.g., directly) between the source STA and the destination STA using a direct link setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z Tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and STAs within or using the IBSS (e.g., all STAs) may communicate directly with each other. The IBSS communication mode may be referred to herein as an "ad-hoc" communication mode.

[0043] When using 802.11ac infrastructure mode of operation or a similar mode of operation, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a width dynamically set via 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 a particular representative embodiment, carrier sense multiple access with collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. With CSMA / CA, STAs (e.g., all STAs), including the AP, may sense the primary channel. If the primary channel is detected / detected and / or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any time in a particular BSS.

[0044] High throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, through a combination of a primary 20 MHz channel with adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0045] A Very High Throughput (VHT) STA may support 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. A 40 MHz and / or 80 MHz channel may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining eight contiguous 20 MHz channels or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, after channel encoding, the data may be passed through a segment parser that may split the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time domain processing may be performed on each stream separately. The streams may be mapped to two 80 MHz channels, and the data may be transmitted by the transmitting STA. At the receiver of the receiving STA, the above operations for the 80+80 configuration may be reversed, and the combined data may be transmitted to the Medium Access Control (MAC).

[0046] Sub-1 GHz operating modes are supported by 802.11af and 802.11ah. The channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, while 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to representative embodiments, 802.11ah may support metered control / machine type communications such as MTC devices in macro coverage areas. MTC devices may have limited capabilities including specific features, e.g., support (e.g., support only) specific bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0047] WLAN systems that may support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, 802.11ah, etc., include a channel that may be designated as a primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by the STA from among all STAs operating in the BSS that support the smallest bandwidth operating mode. In an 802.11ah example, the primary channel for a STA (such as an MTC-type device) that supports (e.g., only supports) 1 MHz mode may be 1 MHz wide, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) setting may depend on the status of the primary channel. For example, if the primary channel is busy because a STA (that only supports a 1 MHz mode of operation) is transmitting to the AP, the entire available frequency band may be considered busy even though a large portion of the frequency band may remain idle and available.

[0048] In the United States, the available frequency bands that may be used with 802.11ah are 902MHz to 928MHz. In South Korea, the available frequency bands are 917.5MHz to 923.5MHz. In Japan, the available frequency bands are 916.5MHz to 927.5MHz. The total available bandwidth for 802.11ah is 6MHz to 26MHz depending on the country code.

[0049] 1D is a system diagram illustrating the RAN 113 and the CN 115 according to one embodiment. As mentioned above, the RAN 113 may communicate with the WTRUs 102a, 102b, 102c over the air interface 116 using NR radio technology. The RAN 113 may also communicate with the CN 115.

[0050] The RAN 113 may include gNBs 180a, 180b, 180c, although it will be understood that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating 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, the gNBs 180a, 108b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may transmit wireless signals to and / or receive wireless signals from the WTRU 102a, for example, using multiple antennas. 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 an unlicensed spectrum, and the remaining component carriers may be on a licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multipoint (CoMP) techniques. For example, the WTRU 102a may receive coordinated transmissions from the gNBs 180a and 180b (and / or gNB 180c).

[0051] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions related to a scalable numerology. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of different or scalable lengths (e.g., absolute times of different lengths that include and / or last for different numbers of OFDM symbols).

[0052] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c without accessing any other RAN (e.g., eNode-Bs 160a, 160b, 160c, etc.). In a standalone configuration, the WTRUs 102a, 102b, 102c may utilize one or more gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in unlicensed bands. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with a gNB 180a, 180b, 180c while communicating / connecting with another RAN, such as an eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement a DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-Bs 160a, 160b, 160c may act as a mobility anchor 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, 102c.

[0053] 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, handover decisions, scheduling of users in the UL and / or DL, support for network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data to User Plane Functions (UPFs) 184a, 184b, routing of control plane information to Access and Mobility Management Functions (AMFs) 182a, 182b, etc. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with each other via an Xn interface.

[0054] 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 is shown as part of the CN 115, it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0055] The AMF 182a, 182b may be connected to one or more gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may function as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, registration area, termination of NAS signaling, mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize the CN support of the WTRUs 102a, 102b, 102c based on the type of service being utilized by the WTRUs 102a, 102b, 102c. Different network slices may be established for different use cases, for example, services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services with machine-type communications (MTC) access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that use other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies like WiFi.

[0056] The SMFs 183a, 183b may be connected to the AMFs 182a, 182b in the CN 115 via an N11 interface. The SMFs 183a, 183b may also be connected to the UPFs 184a, 184b in the CN 115 via an N4 interface. The SMFs 183a, 183b may select and control the UPFs 184a, 184b and configure the routing of traffic through the 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 downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0057] The UPFs 184a, 184b may be connected to one or more gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks such as the Internet 110 to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPFs 184, 184b may perform other functions such as routing and forwarding packets, enforcing user plane policy, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing a mobility anchor, etc.

[0058] The CN 115 may facilitate communication with other networks. For example, the CN 115 may include or 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 an embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b via the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0059] 1A-1D and the corresponding description thereof, one or more, or all of the functions described herein with respect to one or more of the WTRUs 102a-d, base stations 114a-b, eNode-Bs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-ab, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or any other devices described herein may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0060] The emulation device may be designed to implement one or more tests of other devices in a lab environment and / or an operator network environment. For example, one or more emulation devices may perform one or more or all functions while fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices in the communication network. One or more emulation devices may perform one or more or all functions while 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 communication.

[0061] The one or more emulation devices may perform one or more functions, inclusive, while not implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in test scenarios in a test lab and / or in an undeployed (e.g., test) wired and / or wireless communication network to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and / or wireless communication via RF circuitry (which may include, e.g., one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0062] Exemplary Positioning Systems and Technologies Positioning may enable the location (e.g., geographic location) of the WTRU to be determined. In many location applications, precise positioning may be achieved by a combination of multiple technologies including, for example, any of the following: 1) Global Navigation Satellite System (GNSS) based solutions that provide precise location in outdoor scenarios; 2) wireless technologies that offer multiple design options for locating the device (e.g., any of LTE networks, Wi-Fi networks, terrestrial beacon systems (TBS), Bluetooth, etc.); 3) Inertial Measurement Units (IMUs) or sensors that track (e.g., vertical positioning with accelerometers, gyroscopes, magnetometers, and atmospheric pressure sensors, etc.) based on location (e.g., of a user).

[0063] The following terms are used herein for devices and / or network element nodes (e.g., WTRU, gNB, etc.) involved in positioning: When added to a network element, the suffix "based" means that the network element can calculate the position and that the network element can also provide measurements. When added to a network element, the suffix "assisted" means that the node can provide measurements but cannot perform a position calculation.

[0064] Two (eg, main) types of positioning may be supported: WTRU positioning and network positioning.

[0065] For WTRU positioning, the WTRU may (e.g., actively) support or assist in the calculation of its (e.g., geographic) location. WTRU positioning may include WTRU-assisted positioning and WTRU-based positioning. In WTRU-assisted positioning, the WTRU may perform (e.g., make) measurements and provide them to a network-connected device. The network device (e.g., an enhanced serving mobile location center, E-SMLC) may use these measurements to calculate the WTRU's location. In WTRU-based positioning, the WTRU may make measurements (and instead of or in addition to reporting the measurements to a network device), perform a position calculation, and provide (e.g., transmit) the WTRU-calculated location to the network (e.g., a network device or a set of interconnected network devices).

[0066] For network positioning, a network (eg, a network device or set of interconnected network devices) may use measurements or signals (eg, received) from a WTRU to determine the location of that WTRU.

[0067] According to an embodiment, WTRU positioning may include and / or be performed using a GNSS method, an Observed Time Difference of Arrival (OTDOA) method (which may be referred to herein as a “downlink positioning” method), an Enhanced Cell ID (E-CID) method, and any of modifications thereof.

[0068] According to an embodiment, network positioning may be performed including and / or using a time difference of arrival (UTDOA) method (which may be referred to herein as an "uplink positioning" method), and the like, along with modifications thereof.

[0069] Exemplary Global Navigation Satellite System Method As used herein, GNSS methods may refer to common satellite-based positioning methods (using any of the satellite systems such as GPS, Galileo, GLONASS, Beidou, etc.). Network-aided GNSS methods may rely on signals between a WTRU GNSS receiver (possibly of reduced complexity) and a (e.g., continuously) operating GNSS reference receiver network that may have clear sky visibility of the same GNSS constellation as the assisting WTRU. According to an embodiment, two aided modes may be supported: a WTRU-aided mode and a WTRU-based mode.

[0070] WTRU-assisted mode: The WTRU may perform GNSS measurements (e.g., any of pseudo-range, pseudo-Doppler, carrier phase range, etc.) and transmit these measurements to a network (e.g., a network device or set of interconnected network devices) where a position calculation can be performed.

[0071] WTRU-Based Mode: The WTRU performs GNSS measurements and may possibly use additional measurements from other (e.g., non-GNSS) sources and / or assistance data from a network (e.g., a network device or set of interconnected network devices) to calculate its own position (e.g., location). The content of the assistance data may differ depending on whether the WTRU operates in a WTRU-assisted or WTRU-based mode.

[0072] Exemplary Observed Time Difference of Arrival (OTDOA) Positioning Method - Downlink Positioning According to an embodiment, in an OTDOA positioning method, a WTRU may receive signals from a (e.g., reference) cell (e.g., typically a serving cell) and several (e.g., neighboring) cells. The WTRU may measure the (e.g., observed, detected) arrival time differences of these signals (e.g., between any neighboring cell and the reference cell) and report the reference signal time difference (RSTD) to a network (e.g., a network device or set of interconnected network devices). From knowledge of the positions (e.g., locations) of the cells, the fixed timing differences between them, and possibly other information, the network device (or set of devices) can derive the WTRU position, for example, by triangulation (e.g., considering that at least three cells are measured) and / or other types of methods.

[0073] 2 is a system diagram illustrating an example of positioning based on the OTDA method. Any time difference of arrival t3-t1, t2-t1 may determine candidate location hyperbolas 231, 221. The first hyperbolas 231 may correspond to a candidate location of a network element that may have measured the OTDA between the reference cell 20 and the first neighboring cell 21. The second hyperbolas 221 may correspond to a candidate location of a network element that may have measured the OTDA between the reference cell 20 and the second neighboring cell 22. The intersection of the first and second hyperbolas 231, 221 may be an estimated WTRU location 200. At least three timing measurements t1, t2, t3 (e.g., from the reference 20 and the two neighboring cells 21, 22) may enable the location (e.g., coordinates) of the WTRU to be obtained (e.g., estimated).

[0074] The time difference of arrival may be measured on a (e.g., predetermined, known) signal. Cell-specific reference signals (CRS), which may be transmitted by any cell 20, 21, 22 and known to any WTRU, may be candidates for this measurement. Positioning reference signals (PRS) may also be used, for example, to improve the accuracy of the OTDA method.

[0075] According to an embodiment, the WTRU may obtain a time difference of arrival using the CRS and / or PRS. For example, by detecting a particular RS and / or PRS from a base station (BS), the WTRU may obtain a time of arrival (TOA) of a subframe including the particular RS and / or PRS. In the embodiments described herein, the base station may be, for example, either an eNB or a gNB. A time difference of arrival (TDOA) for a neighboring cell 21, 22 may be calculated by subtracting the TOA of the neighboring cell 21, 22 from the TOA of the reference cell 20. According to an embodiment, the WTRU may perform a cross-correlation with a (e.g., known) sequence to determine the TOA of the CRS and / or PRS from the BS. The WTRU may obtain two TOAs for two BSs, respectively. The WTRU may obtain the TDOA by calculating the difference between both TOAs after considering different schedules of the CRS / PRS from different BSs.

[0076] Exemplary Enhanced Cell ID (E-CID) Positioning Method The E-CID positioning method is based on the Cell ID (CID) method. The CID method may refer to a network-based positioning method in which a network (e.g., a network device or a set of interconnected network devices) may determine the location of the WTRU using knowledge of which cell is the serving cell of the WTRU. The E-CID positioning method may improve the accuracy of the location by combining the cell knowledge with measurements made by the WTRU and the network, such as, for example, any of the following: round trip time (RTT) measurements that provide distance information, angle of arrival AOA / angle of departure (AOD) measurements that provide direction information, and reference signal received power (RSRP) measurements that may provide additional information. The E-CID positioning method may include, for example, one to at least three base stations. The measurements may be performed at the WTRU and / or the BS and reported to a (e.g., location) server, where, for example, the location of the WTRU may be calculated.

[0077] Exemplary Uplink Time Difference of Arrival (UTDOA) Positioning Method Example - Uplink Positioning According to an embodiment, an uplink positioning method (e.g., UTDOA) may utilize timing (e.g., measured, observed, detected) at multiple network location measurement units (LMUs) of uplink signals transmitted from a WTRU. The LMUs may measure the timing of received signals using, for example, assistance data received from a positioning server. The resulting measurements may be used to obtain (e.g., determine, estimate) the location of the WTRU.

[0078] New use cases and applications for 5G systems may drive stricter location expectations compared to traditional wireless systems: for example, WTRUs may need to be located with an accuracy of 0.3 m and a positioning service latency of 10 ms.

[0079] According to an embodiment, the positioning method may enable obtaining the location of the WTRU with an accuracy location capability equal to, for example, at least 0.3 m and a latency of, for example, up to 10 ms. Positioning services may also be useful in some NR use cases, such as when the WTRU is power limited. Such NR use cases may include, for example, any of Massive Machine Type Communications (mMTC) and Vehicle to Anything (V2X) applications.

[0080] Reducing the computational complexity and / or time of the positioning method may in turn reduce power consumption (e.g., positively impacting the charging and / or life of the WTRU's battery). The WTRU may be connected for limited periods to limit the attendant power consumption and preserve battery life / charging time, which may limit signaling opportunities for transmitting positioning indications. Positioning methods that support WTRU positioning during Radio Resource Control (RRC) idle / inactive modes may enable WTRU positioning and tracking of power-limited WTRUs. Positioning methods that support WTRU positioning in RRC idle / inactive modes may increase the accuracy of the positioning method.

[0081] Bounded (e.g., strict) latency for positioning measurement updates may be useful in some NR use cases. For example, establishing an RRC connection (e.g., sending information indicating measurements) before providing reports may result in additional reporting delays. Supporting WTRU positioning reporting directly from RRC idle / inactive mode may allow for reduced latency in NR positioning measurement and reporting (e.g., sending measurement reports).

[0082] According to embodiments, a measurement may be identified by a (e.g., unique) identifier (ID), which may be referred to herein as a "measurement ID." According to embodiments, a WTRU may be configured to perform multiple measurements. The measurement ID may identify a particular measurement among a set of measurements.

[0083] According to an embodiment, a measurement report may be identified by a (e.g., unique) identifier (ID), which may be referred to herein as a "measurement report ID." According to an embodiment, a WTRU may be configured to perform multiple measurement reports. The measurement report ID may identify a particular measurement report among a set of measurement reports between the network and the WTRU. When transmitted by the WTRU to the network, the measurement report ID may enable identification of the reporting configuration.

[0084] According to an embodiment, the WTRU may be identified by an (e.g., unique) identifier (ID), which may be referred to herein as a WTRU ID, a WTRU identifier, or a WTRU specific ID. The WTRU ID may be used to (e.g., uniquely) identify the WTRU (e.g., within a tracking area). The WTRU ID may be managed by the network (e.g., one of the AMF and MME) and may not be deleted when the WTRU moves to an idle / inactive state (e.g., while remaining in the same tracking area). According to an embodiment, the WTRU ID may be one of a System Architecture Evolution Temporary Mobile Subscription Identifier (S-TMSI), a 5G-S-TMSI, and a Positioning-TMSI (P-TMSI).

[0085] According to an embodiment, the WTRU may be temporarily identified by a temporary identifier, for example, for the purpose of encoding and decoding transmissions between the WTRU and the BS. The temporary WTRU identifier may be any of the following: a Cell Radio Network Temporary Identifier (C-RNTI), a Temporary Cell RNTI (T-CRNTI), a Random Access RNTI (RA-RNTI), a Temporary Positioning RNTI (TP-RNTI). The TP-RNTI may be temporarily assigned by the (e.g., reference) BS for the purpose of identifying transmissions between the (e.g., reference) BS and the WTRU. The TP-RNTI may be local to (e.g., managed, assigned by) any of the AMF, MME, positioning server, and gNB. The TP-RNTI may, for example, (e.g., uniquely) identify the WTRU (e.g., within a tracking area).

[0086] Downlink positioning measurement and configuration example According to an embodiment, while in an active (e.g., RRC connected) mode, the WTRU may be configured by (e.g., receiving configuration information) from a BS to perform DL positioning measurements (e.g., applying the configuration information). For example, the WTRU may be configured to perform measurements and / or be scheduled to perform measurements in any WTRU RRC state (e.g., connected, idle, inactive). DL positioning measurements may be performed using reference signals (RSs) received from a serving and / or neighboring BS on either a periodic, semi-periodic, or aperiodic basis. The WTRU may utilize the RSs to obtain (e.g., estimate) various parameters related to WTRU positioning (e.g., any of RTT, AOA, RSTD, etc.). The WTRU may obtain (e.g., estimate) positioning using broadcast RSs transmitted by (e.g., received from) one or any number of BSs. The RS may include reference signals (e.g., any of a Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Demodulation Reference Signal (DMRS) on a common Physical Downlink Control Channel (PDCCH), CRS, PRS, etc.) that may be broadcast or otherwise transmitted / received from the BS. According to embodiments, the transmission of the RS by the BS may occur, for example, in time coordination with other transmitting BSs (e.g., any of simultaneously, synchronously, asynchronously, etc.). According to embodiments, the transmission of the RS from different BSs may occur in a common band or across multiple bands. According to embodiments, the measurement of the (e.g., transmitted) RS may be configured by the (e.g., network / serving) BS according to a (e.g., desired) schedule (e.g., any of periodic, aperiodic, semi-periodic, etc.). In other words, the WTRU may be configured to receive configuration information, which may indicate a time schedule on which the RS may be transmitted (and, in turn, measured). According to embodiments, the measurement observations may be configured on a schedule that is the same or different from the schedule of the RS transmission. For example, the measurement observations may be configured as a subset (eg, a portion) of all RS transmissions (eg, every other transmission, every third transmission, etc.).The periodicity of the schedule may be maintained by various methods (e.g., by any of the following: System Frame Number (SFN), an internal WTRU clock, a GNSS / GPS synchronized clock). The WTRU may be configured (e.g., receive configuration information) to store one or more measurements while in an idle / inactive mode (e.g., store the last N measurements, where N is an integer value).

[0087] According to an embodiment, a WTRU in idle / inactive mode may monitor any of the broadcast channels (e.g., any of the common PDCCH or physical broadcast control channel (PBCH), etc. to receive an indication that the WTRU may initiate an RRC connection (e.g., any of the CN or RAN pages). According to an embodiment, the WTRU may initiate (e.g., send) an RRC connection request via a conventional random access channel (RACH) procedure (e.g., any of the two-step and four-step RACH procedures). When the WTRU is in the RRC connected mode, the WTRU may reconfigure (e.g., receive an information indication) to terminate or modify its idle / inactive mode positioning measurements (e.g., operable when the WTRU is in idle / inactive mode) via any conventional RRC and / or location information service protocol messaging.

[0088] 3 illustrates an example procedure 300 for idle / inactive mode positioning measurements. For clarity and brevity, "IDLE mode positioning measurements" may be used interchangeably herein with "IDLE mode positioning measurements."

[0089] 3, in step 312, a WTRU in RRC connected mode 310 may be configured by the serving BS to perform (e.g., periodic) IDLE mode positioning measurements. In step 314, the WTRU may receive an RRC connection release command from the serving BS. In step 316, the WTRU may initialize a (e.g., IDLE mode positioning measurement) timer (e.g., corresponding to an IDLE / inactive mode positioning configuration received from the BS). In step 318, the WTRU may receive a Release RRC Connection message and may transition to an IDLE / inactive state 360. In step 362, the WTRU may monitor a (e.g., IDLE mode positioning measurement) timer. In step 364, it may be determined whether the (e.g., IDLE mode positioning measurement) timer has expired. At or after expiration of the timer, in step 366, the WTRU may receive a signal for measurement (e.g., any of the RS, PRS, Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS)) from any of the broadcast transmissions of the (e.g., observed) BSs. In step 368, the WTRU may calculate positioning measurement parameters (e.g., values) from the received signals. The WTRU may calculate measurements such as, for example, any of the RSTD between neighboring BSs and the AOA of the (e.g., received and measured) RS. If the WTRU completes positioning measurements, for example according to a configured observation measurement schedule (e.g., period), in step 370, the WTRU may reinitialize the IDLE mode positioning timer and may resume the idle / inactive mode procedure (e.g., the WTRU may transition to step 362).

[0090] 4 illustrates an example of signaling for idle / inactive mode positioning measurements 400. Configuration information for configuring a WTRU to perform idle / inactive mode positioning measurements may be received by the WTRU in RRC connected mode 412. The configuration information may include a measurement ID, a type of signal on which the measurement may be performed (e.g., any of RS, PRS, PSS, SSS, etc.,...), reference and neighboring (e.g., measurement) BSs, a measurement type (e.g., any of RTT, RSTD, AOA, etc.,...), and any of schedule information indicating time intervals during which the WTRU may perform positioning measurements (e.g., any of periodic, semi-periodic, aperiodic timing information). The WTRU may receive an RRC connection release 414 and may proceed (e.g., transition) to any of idle / inactive modes 418. The WTRU may receive a broadcast signal (e.g., PSS, SSS) 466 on which the WTRU may perform measurements 468 according to any embodiment of the configured idle / inactive mode positioning measurements.

[0091] Downlink positioning measurement reporting and configuration example According to an embodiment, while in an active (e.g., RRC connected) mode, the WTRU may be configured to transmit DL positioning measurement reports to the BS. The reports may be scheduled and / or transmitted in any WTRU RRC state (e.g., connected, idle, inactive). The reports may include and / or indicate information regarding measurements made from one or more possibly configured idle / inactive mode positioning measurements. The measurement reports may be configured to be transmitted and may be transmitted on any of a periodic, semi-periodic, and aperiodic basis.

[0092] According to an embodiment, the periodicity of the schedule can be maintained by various methods (e.g., any of the following): SFN, internal WTRU clock, GNSS / GPS synchronized clock. The WTRU can trigger, be triggered to provide, and / or provide (e.g., transmit) a positioning measurement report based on a (e.g., pre-configured) network event observed by the WTRU (e.g., any of the following): WTRU leaving a tracking area ID, WTRU reselecting a new BS, etc. The WTRU can trigger, be triggered to provide, and / or provide (e.g., transmit) a positioning measurement report based on a broadcast indication received from the BS (e.g., System Information Block (SIB) indication of a desired measurement report ID, etc.). The WTRU can be configured and provided (e.g., transmit) one, multiple, or a (e.g., mathematical) function of multiple measurements in a report (e.g., transmit a report with one measurement, the last N measurements, or an average of the last N measurements). The WTRU can be configured with a WTRU-specific identifier (ID) for the measurement report. The WTRU specific ID may be unique within a region of a network coverage area (eg, a BS, a tracking region, a PLMN, etc.). A WTRU measurement report may be configured with one or more measurement report IDs.

[0093] Example of one-message report using RACH preamble According to an embodiment, the WTRU may be configured to trigger, be triggered to transmit, and / or transmit its measurement reports on a (e.g., available) physical RACH (PRACH). The (e.g., target) PRACH may be selected by the WTRU according to one or more of a variety of criteria (e.g., any of the strongest associated PSS signal strength, the first available PRACH after a configured measurement indication, etc.).

[0094] According to an embodiment, the WTRU may trigger, be triggered to transmit, and / or transmit the report via the PRACH using a RACH preamble. The RACH preamble message may be WTRU specific or available for random access. The set of available RACH preambles may be configured for the WTRU while in active (e.g., RRC connected) mode or may be provided as system information (SI) that may be broadcast or requested by the BS monitoring the target PRACH resource. According to an embodiment, the RACH preamble may be associated with a WTRU specific ID (e.g., the RACH preamble seed may be a function of the WTRU specific ID, etc.). According to an embodiment, the RACH preamble may be associated with a WTRU measurement ID (e.g., a cyclic shift of the RACH preamble may be calculated as a function of the measurement ID, etc.). According to an embodiment, the measurement value of the measurement report may be associated with the RACH preamble generation (e.g., a binary sequence modulating the RACH preamble may be XORed with the measurement report field, etc.). According to an embodiment, the generated positioning RACH preamble can be transmitted in a target RACH preamble and can be received by one or more of a plurality of transmission / reception points (TRPs). The positioning RACH preamble can be received at one or more BSs.

[0095] FIG. 5 illustrates an example of a one-message positioning reporting procedure 500 using a RACH preamble. At step 512, the WTRU may be configured with an IDLE mode positioning measurement report (e.g., to report measurements in an idle / inactive mode). For example, the WTRU may receive a periodic WTRU positioning measurement report configuration while in the RRC connected mode 510. The positioning measurement report configuration may include, for example, a unique WTRU (e.g., specific) ID for the positioning area (e.g., S-TMSI, etc.) and a measurement report ID. At step 514, the WTRU may receive an RRC connection release initiate message from the serving BS. At step 516, the WTRU may initialize a (e.g., WTRU IDLE mode positioning measurement report) timer. At step 518, the WTRU may receive a release RRC connection message and may transition to an idle / inactive state 560. At step 562, the WTRU may monitor a (e.g., IDLE mode positioning report) timer. In step 564, it may be determined whether a (e.g., IDLE mode positioning report) timer has expired. In step 566, upon or after expiration of the timer, the WTRU may select a (e.g., appropriate) PRACH resource (e.g., the next available PRACH as determined by synchronization signal block (SSB) monitoring) for transmitting its positioning measurement report. In step 568, the WTRU may generate a positioning RACH preamble associated (e.g., uniquely) with its WTRU-specific ID and / or measurement ID. The RACH preamble may be generated using a seed that may be determined, for example, from a pseudo-random sequence as a function of any variable including, but not limited to, any of the following: a WTRU ID, a measurement ID, and an average of the last N measured positioning values. In step 570, the WTRU may transmit the (e.g., generated) RACH preamble in the (e.g., target) PRACH resource.In step 572, the WTRU may reinitialize the positioning measurement report timer and may resume the idle / inactive mode procedure (eg, the WTRU may transition to step 562).

[0096] FIG. 6 illustrates an example of a signaling exchange for preamble-based positioning measurement reporting 600. Configuration information for configuring the WTRU to perform idle / inactive mode positioning reporting may be received by the WTRU in RRC connected mode 612. The configuration information may include any of the following: WTRU ID (e.g., Positioning-TMSI), periodicity (e.g., time interval during which the WTRU may perform positioning measurement reporting), positioning-specific PRACH preamble, measurement report ID, etc.). The WTRU may receive RRC connection release 614 and proceed (e.g., transition) to any of the idle / inactive modes 618. The WTRU may send positioning measurement reports 620 to the BS in the RACH preamble according to the configured periodicity and / or according to any embodiment disclosed herein. The BS may forward the positioning measurement reports 622 to a location server.

[0097] Example of one message report added to the RACH preamble According to an embodiment, the WTRU may be configured to transmit its measurement reports on a (e.g., available) PRACH. The (e.g., target) PRACH may be selected by the WTRU according to one or more various criteria (e.g., any of the strongest associated PSS strength, the first available PRACH after a configured measurement indication, etc.).

[0098] According to an embodiment, the WTRU may transmit its positioning measurement report by encoding, modulating and / or appending the report to (e.g., at the end of) a RACH preamble transmitted in (e.g., selected) PRACH resource. According to an embodiment, the RACH preamble may indicate the presence of an appended report (e.g., a unique positioning-based RACH preamble). According to an embodiment, the RACH preamble may have an association with the WTRU (e.g., a RACH preamble generated as a function of S-TMSI). According to an embodiment, the RACH preamble may be shared by multiple WTRUs in the PRACH resource. According to an embodiment, the WTRU measurement report may include any of one or more associated report fields (e.g., any of a WTRU-specific ID, a measurement report ID, one or more measurements, etc.). According to an embodiment, the data may be appended with a calculated cyclic redundancy check on the data to be transmitted. According to an embodiment, the measurement report may be prepared for transmission by any of the following procedures. 1) The measurement report may be coded by any of various coding techniques (e.g., polar, low density parity check (LDPC), etc.). 2) The measurement report may be scrambled by one or more scrambling sequences (e.g., pseudorandom sequence generation (PRSG), etc.). 3) The measurement report may be modulated by one or more mapping methods (quadrature phase shift keying (QPSK), M-ary quadrature amplitude modulation (QAM), etc.). 4) The modulated measurement report may be appended with a RACH preamble by multiplexing in various ways (e.g., time and / or frequency). 5) The appended RACH preamble and the measurement report may be transmitted on the target PRACH resource.

[0099] FIG. 7 illustrates an example of a one-message downlink positioning measurement reporting procedure 700 with reports appended to the PRACH preamble. At step 712, the WTRU may be configured with IDLE mode positioning measurement reports (e.g., to report measurements in idle / inactive mode). For example, the WTRU may receive a periodic WTRU measurement report configuration while in RRC connected mode. The measurement report configuration may include a WTRU-specific identifier (ID) (e.g., unique to the positioning area (e.g., S-TMSI)) and any of the following measurement report IDs. At step 714, the WTRU may receive an RRC connection release message from the serving BS. At step 716, the WTRU may initialize a WTRU (e.g., IDLE mode positioning measurement report) timer. At step 718, the WTRU may receive a release RRC connection message and may transition to an idle / inactive state 760. At step 762, the WTRU may monitor a (e.g., IDLE mode positioning report) timer. In step 764, it may be determined whether a (e.g., IDLE mode positioning report) timer has expired. In step 766, upon or after expiration of the timer, the WTRU may select a (e.g., appropriate) PRACH resource (e.g., the next available PRACH as determined by SSB monitoring) for transmitting its positioning measurement report. In step 768, the WTRU may generate a positioning measurement report by appending (e.g., relevant) fields (e.g., any of a WTRU-specific ID, a measurement ID, one or more measurements, a CRC). In step 770, according to an embodiment, the WTRU may encode the data, e.g., using polarity and / or other encoding algorithms. According to an embodiment, the WTRU may scramble the data, e.g., using a PRSG generated, e.g., from a function of its own Cell Radio Network Temporary Identifier (C-RNTI).According to an embodiment, the WTRU may modulate the data as (e.g., QPSK) symbols and may multiplex the data to the RACH preamble (e.g., append the data to the RACH preamble). In step 772, the WTRU may transmit the RACH preamble appended with the positioning measurement report in the (e.g., target) PRACH resource. In step 774, the WTRU may reset its (e.g., IDLE mode positioning measurement report) timer and resume the WTRU idle / inactive mode procedure (e.g., the WTRU may transition to step 762).

[0100] FIG. 8 illustrates an example of a signaling exchange for idle / inactive mode positioning measurement reporting with a report appended with a RACH preamble 800. In FIG. 8, a signaling exchange may be performed between the network and the WTRU, and the WTRU may provide (e.g., transmit) a one-message-based positioning report appended with a RACH preamble (e.g., according to any disclosed embodiment). With reference to FIG. 8, configuration information for configuring the WTRU to perform idle / inactive mode positioning reporting may be received by the WTRU in RRC connected mode 812. The configuration information may include any of the following: WTRU ID (e.g., Positioning-TMSI), periodicity (e.g., time interval during which the WTRU may perform positioning measurement reporting), report encryption key, positioning-specific PRACH preamble, measurement report ID, etc. The WTRU may receive an RRC connection release 814 and may proceed (e.g., transition) to either idle / inactive mode 818. The WTRU may send the measurement report appended to the RACH preamble 822 to the BS 820 according to a configured periodicity and / or according to any embodiment disclosed herein. The BS may forward the positioning measurement report to a location server 824.

[0101] Example of two-message reporting using PRACH and PUSCH According to embodiments, the WTRU may be configured to transmit its measurement reports on an available PRACH. According to embodiments, the target PRACH may be selected by the WTRU according to any number of different criteria (e.g., any of the strongest associated PSS strength, the first available PRACH after a configured measurement indication, etc.).

[0102] According to an embodiment, the WTRU may transmit a RACH preamble in the target PRACH resource. According to an embodiment, the selected RACH preamble may be transmitted as either a contention-based RACH preamble or a contention-free RACH preamble. According to an embodiment, the RACH preamble may signal (e.g., uniquely) the WTRU's intent to transmit an idle / inactive mode positioning report. According to an embodiment, the set of available RACH preambles may be configured for the WTRU while in active (e.g., RRC connected) mode or may be provided as system information (SI) that may be broadcast and / or requested by the BS monitoring the target PRACH resource.

[0103] According to an embodiment, after transmitting the RACH preamble, the WTRU may monitor (e.g., receive) a common PDCCH for a RACH response (RAR). According to an embodiment, the RAR may include information indicating that the transmitted RACH preamble was received by the BS and may provide the WTRU with a temporary ID (e.g., T-CRNTI, etc.). According to an embodiment, the RAR may include, indicate, or otherwise provide (collectively "provide") information indicating, including, a timing advance (TA) for configuring the WTRU's uplink synchronization. The terms "including," "including information indicating," "indicating," and "providing" may be used interchangeably herein. According to an embodiment, the RAR may provide (e.g., include information indicating) reporting resources for the WTRU to transmit positioning measurement reports. According to an embodiment, the reporting resources may be either WTRU-specific and / or common (e.g., shared). According to an embodiment, the reporting resources may be transmitted on a separate physical channel (e.g., any of the Physical Uplink Control Channel (PUCCH), the Physical Uplink Shared Channel PUSCH, etc.). According to an embodiment, the reporting resource may have a configured time relationship to the RAR (eg, any of N slots, M subframes, etc., where N and M are integer values, for example).

[0104] According to an embodiment, the WTRU may transmit its positioning measurements on the configured reporting resources as provided / indicated in the RAR. According to an embodiment, the measurement report may include one or more fields (e.g., any of the following: WTRU-specific ID, measurement ID, one or more measurements, CRC, etc.). According to an embodiment, the measurement report may be prepared for transmission by any of the following procedures: 1) The measurement report may be encoded by various coding techniques (e.g., polarity, LDPC, etc.); 2) The measurement report may be scrambled by one or more scrambling sequences (e.g., PRSG, etc.); 3) The measurement report may be modulated by one or more mapping methods (e.g., QPSK, M-ary QAM, etc.); 4) The measurements may be multiplexed (e.g., any of the following: time, frequency, code multiplexed, etc.) with other physical channels (e.g., any of the following: PUSCH, PUCCH, PRACH, etc.) as part of an uplink transmission, or the measurement report may be transmitted individually.

[0105] According to an embodiment, the WTRU may reset its positioning measurement report timer and resume idle / inactive mode operation after the transmission (e.g., immediately after). According to an embodiment, the WTRU may monitor the PDCCH search space for an acknowledgement of the measurement report transmission and may resume idle / inactive mode operation (e.g., if an acknowledgement is received).

[0106] FIG. 9 illustrates an example of a two-message downlink positioning measurement reporting procedure 900 using PRACH and PUSCH. At step 912, the WTRU may be configured with an IDLE mode positioning measurement report (e.g., to report measurements in an idle / inactive mode). For example, the WTRU may receive a periodic WTRU measurement report configuration while in an RRC connected mode. According to the illustrated example, the measurement report configuration may include a WTRU (e.g., unique) ID (e.g., unique to a positioning area such as S-TMSI) and any of a measurement report ID. At step 914, the WTRU may receive an RRC connection release initiate message from the serving BS. At step 916, the WTRU may initialize a (e.g., WTRU IDLE mode positioning measurement report) timer. At step 918, the WTRU may receive a release RRC connection message and may transition to an idle / inactive state 960. At step 962, the WTRU may monitor a (e.g., IDLE mode positioning report) timer. In step 964, it may be determined whether a timer (e.g., IDLE mode positioning report) has expired. In step 966, the WTRU may select a (e.g., appropriate) PRACH resource for transmitting its positioning measurement report (e.g., the next available PRACH as determined by SSB monitoring), e.g., upon timer expiration. The WTRU may select a positioning-specific RACH preamble, which the WTRU may transmit in the target PRACH resource in step 968. In step 970, the WTRU may monitor a common PDCCH associated with the PRACH resource for (e.g., to receive, detect) an RAR. In step 972, it may be determined whether an RAR has been received by the WTRU.In step 974, the WTRU may decode the received RAR (e.g., indicating T-CRNTI, TA, UL grant), synchronize its uplink transmission according to the provided TA, and prepare a positioning measurement report to be transmitted in the provided uplink reporting resource (e.g., PUSCH). In step 976, the WTRU may obtain (e.g., generate) positioning measurements. The positioning measurement report may include any of a WTRU-specific ID (e.g., S-TMSI), a measurement ID, one or more measurements, and a CRC. The report may be generated according to the UL grant and may be transmitted on the granted resource in step 980. After transmitting the measurement report, in step 982, the WTRU may reset its positioning measurement report timer and may resume the idle / inactive mode procedure (e.g., the WTRU may proceed to step 960. If in step 972 it is determined that the RAR was received (e.g., within the appropriate time interval), the WTRU may proceed to step 966 to retransmit the positioning measurement report.

[0107] FIG. 10 illustrates an example of a signaling exchange for two-message downlink positioning measurement reporting using PRACH and PUSCH 1000. In FIG. 10, a signaling exchange may be performed between the network and the WTRU, and the WTRU may provide two-message idle / inactive mode positioning reporting using PRACH and PUSCH. With reference to FIG. 10, configuration information for configuring the WTRU to perform idle / inactive mode positioning reporting may be received by the WTRU in RRC connected mode 1012. The configuration information may include any of the following: WTRU ID (e.g., Positioning-TMSI), periodicity (e.g., time intervals at which the WTRU may perform positioning measurement reporting), positioning specific PRACH preamble, report encryption key, measurement report ID, etc.). The WTRU may receive an RRC connection release 1014 and may proceed (e.g., transition) to idle / inactive mode 1018. The WTRU may transmit a first positioning message MSG1 1020 requesting to send a positioning measurement report according to a configured periodicity, e.g., using a RACH preamble. The WTRU may receive a second positioning message MSG2 1022 in an RAR, e.g., including any of a temporary identifier, a UL grant, a TA, etc. The WTRU may transmit a third positioning message MSG3 1024 in a PUSCH according to the UL grant, the third positioning message MSG3 1024 including the WTRU ID and any of the positioning measurement reports according to any embodiment above. The BS may forward the positioning measurement report to the location server 1026.

[0108] Example of reconfiguring and terminating a measurement report According to an embodiment, the measurement reports may be terminated and / or reconfigured in various ways. The termination and / or reconfiguration of the measurement reports may be performed, for example, while the WTRU is in RRC connected mode. A WTRU in idle / inactive mode may monitor a broadcast channel, such as a common PDCCH or PBCH, to indicate that the WTRU may initiate an RRC connection (e.g., either CN and RAN paging). The WTRU may initiate an RRC connection request via a (e.g., conventional) RACH procedure (e.g., a two-step or four-step RACH procedure). If the WTRU is in RRC connected mode, the WTRU may reconfigure to terminate or change (e.g., modify) its idle / inactive mode positioning measurements via any of conventional RRC and location information service protocol messaging.

[0109] Modified PRACH Example for Uplink-Based Positioning According to an embodiment, uplink-based positioning may be triggered at a WTRU when it observes (e.g., detects) a change (e.g., any of RSRP, AoA, RTT, etc.) in a (e.g., received) downlink reference signal (e.g., any of PSS, SSS, DL-PRS, DMRS on a common PDCCH, etc.) received from one or more BSs (e.g., any of gNBs, eNBs, TRPs) within its tracking area. Detecting a change in the downlink signal received from a different BS may indicate a positioning change (e.g., a change in location) of the WTRU.

[0110] According to embodiments, the WTRU may be configured to transmit (e.g., periodic) uplink-based positioning-related measurements at (e.g., specific) times, e.g., while in an idle / inactive mode. According to embodiments, the WTRU may be configured with (e.g., idle / inactive mode) positioning update parameters (e.g., any of duration, start time, stop time, etc.), e.g., while the WTRU is in an active (e.g., RRC connected) mode, or may be provided as system information (SI). According to embodiments, in the case of (e.g., idle / inactive mode) positioning updates, the WTRU in idle / inactive mode may perform uplink reference signal transmission, e.g., of an uplink positioning reference signal. Although the embodiments are described herein for a WTRU in idle / inactive mode, they are not limited to a WTRU in idle / inactive mode, and may also be applicable to a WTRU in connected mode, e.g.,

[0111] Example of an uplink positioning reference signal using PRACH and PUSCH 11 illustrates an example of an uplink-based positioning update procedure 1100. According to the procedure, a WTRU 1110 in idle / inactive mode may be configured to perform a positioning update using allocated resources on the PRACH and / or PUSCH 1111. According to an embodiment, the WTRU 1110 may select a BS 1101 to perform an uplink-based positioning procedure in idle / inactive mode (e.g., based on downlink measurements of a downlink synchronization signal such as any of the PSS, SSS, DM-RS of a common PDCCH, etc.). The BS 1101 selected by the WTRU 1110 to initiate the uplink-based positioning procedure may be referred to herein as the reference BS 1101.

[0112] According to an embodiment, one or more preambles from a set of RACH preambles may be assigned for performing idle / inactive mode positioning. A preamble assigned for idle / inactive mode positioning, which may be referred to herein as a positioning preamble, may be used by the WTRU 1110 to transmit a positioning request. A positioning preamble may not be assigned for a contention-based RACH procedure and / or a contention-free RACH procedure. In other words, a positioning preamble may be different from other preambles assigned for (e.g., any other) RACH procedure. According to an embodiment, a preamble may be common to all or a set of WTRUs in a cell for performing idle / inactive mode positioning (e.g., contention-based idle / inactive mode positioning). According to an embodiment, a set of (e.g., positioning) resources may be assigned (e.g., uniquely) for positioning request transmission. For example, a positioning request may be transmitted by a transmission (e.g., of a preamble assigned for other purposes, such as idle / inactive mode positioning or a RACH procedure) in a (e.g., uniquely) assigned positioning resource. According to an embodiment, the time / frequency resources assigned for idle / inactive mode positioning may not be assigned for contention-based RACH procedures and / or contention-free RACH procedures. In other words, the time / frequency resources assigned for idle / inactive mode positioning request transmissions may be different from other time / frequency resources assigned for (e.g., any other) RACH procedures. According to an embodiment, the assignment (e.g., configuration) of preambles (and / or positioning resources) for idle / inactive mode positioning request transmissions may be communicated to the WTRU 1110 (e.g., in system information). According to an embodiment, the WTRU 1110 may receive (e.g., other) parameters, which may include any of the following: preamble power, positioning random access response (PRAR) window size, power ramping factor, and maximum number of retransmissions.

[0113] According to an embodiment, the WTRU 1110 may initiate an uplink-based positioning procedure in idle / inactive mode, for example after receiving an RRC connection release 1112. According to an embodiment, the WTRU 1110 may transmit a positioning MSG1 1114, which may be referred to herein as a positioning request, to the reference BS 1101. The positioning request 1114 may be conveyed (e.g., transmitted) using either transmitting a positioning-specific preamble and transmitting on a positioning-specific resource. According to an embodiment, the WTRU 1110 may select (e.g., randomly) one of the positioning-specific preambles (e.g., assigned for idle / inactive mode positioning). According to an embodiment, the WTRU 1110 may transmit a selected positioning-specific preamble to the reference BS 1101 using a (e.g., time / frequency) resource, or may transmit a (e.g., any) preamble (e.g., assigned for idle / inactive mode positioning or for other purposes such as RACH procedures) within a positioning-specific resource (e.g., specifically) reserved for positioning request transmission. According to an embodiment, the WTRU 1110 may send (e.g., transmit) a selected preamble sequence, e.g., within system information, using a PRACH configuration (e.g., time / frequency resource) that may be provided or configured by the reference BS 1101. According to an embodiment, the WTRU 1110 may be configured 1111 with any of a set of positioning-specific preambles and a set of positioning-specific resources for transmitting a positioning request.

[0114] According to an embodiment, after sending a positioning request 1114 (e.g., either a positioning preamble transmission and a transmission within a positioning resource), the WTRU 1110 may, for example, monitor for reception of a positioning MSG2 RAR 1116 (e.g., PRAR) within a PRAR (e.g., time) window 1115. The positioning random access response 1116 may be referred to herein as either a "positioning RAR" and a "PRAR". According to an embodiment, monitoring the PRAR may include monitoring a Radio Network Temporary Identifier (RNTI). The RNTI may be, for example, similar / similar to a Random Access RNTI (RA-RNTI), which is specific to the time / frequency resource used to transmit the positioning preamble in idle / inactive mode. According to an embodiment, monitoring the RNTI may include monitoring a control channel or downlink control information (DCI) masked or scrambled (e.g., with CRC scrambling) with the RNTI. According to an embodiment, a control channel or DCI may include the PRAR 1116 or may be associated with a data channel that may carry the PRAR. According to an embodiment, the PRAR 1116 may include information indicating to which transmitted preamble the PRAR 1116 may correspond or be intended. According to an embodiment, multiple PRARs (e.g., for different transmitted preambles that may have been transmitted by different WTRUs) may be transmitted simultaneously (e.g., on the same control or data channel).

[0115] According to an embodiment, the PRAR 1116 may include any of a Timing Advance (TA) value, a Temporary WTRU identifier (e.g., a Temporary Cell (T-CRNTI), a Bandwidth Partition (BWP), a set of resources (e.g., time / frequency resources) for transmitting a WTRU (e.g., unique) ID, and a UL configuration (e.g., time / frequency resources) for transmitting an uplink reference signal (e.g., any of an uplink positioning reference signal UL PRS, UL SRS, UL DM-RS). The UL configuration may include any of a bandwidth, a time / frequency resource, and several repeated reference signal transmissions (e.g., several repetitions). In a variant, in addition to or instead of the temporary WTRU identifier, a new set of identifiers may be assigned by the reference BS for inclusion in the PRAR 1116. The new identifiers may be local to (e.g., managed, assigned by) any of the AMF, MME, and positioning server (e.g., a Temporary Positioning RNTI (TP-RNTI). According to an embodiment, the WTRU (e.g., unique) ID is , e.g., S-TMSI, 5G-S-TMSI. According to embodiments, a (e.g., unique) identifier for performing idle / inactive mode positioning may be assigned to the WTRU, which may be referred to herein as Positioning-TMSI. Configuration of the Positioning-TMSI by the network may be performed during an active (e.g., RRC connected) state. According to embodiments, the Positioning-TMSI may be unique for a WTRU within its tracking area. According to embodiments, when the tracking area is changed, a new Positioning-TMSI may be assigned to the WTRU as part of a tracking area update procedure.

[0116] According to an embodiment, if the WTRU does not receive any response (e.g., including a PRAR and scrambled with the RA-RNTI) indicating a preamble transmitted by the WTRU 1110 within the PRAR window 1115, the WTRU 1110 may send another preamble (e.g., at a later time). The response (e.g., received or expected to be received in the PRAR window 1115) may include information indicating the preamble transmitted by the WTRU 1110 in the positioning request 1114. According to an embodiment, the later transmission may be at a higher power. The power may be limited to a maximum power. According to an embodiment, the WTRU 11110 may wait to receive a PRAR 1116 from the reference BS (e.g., until the end of the PRAR window 1115). According to an embodiment, the sequence of transmission and waiting may continue until the reference BS1 1101 can respond with a PRAR 1116 or until a maximum number of preamble transmissions can be reached. According to an embodiment, the reference BS may transmit in response to a single preamble transmission or multiple preamble transmissions, and the WTRU 1110 may receive the PRAR 1116.

[0117] According to an embodiment, if the WTRU 1110 receives a PRAR 1116 that may be intended for it (e.g., indicating a positioning preamble transmitted by the WTRU 1110 in the positioning request 1114), the WTRU 1110 may transmit a positioning MSG3 1118 that includes its (e.g., unique) WTRU ID and a repetition 1120 of the UL PRS transmission 1118 on the specified resources. According to an embodiment, the WTRU 1110 may use a temporary identifier (e.g., one of T-CRNTI, TP-RNTI) received in the PRAR 1116 to scramble its uplink transmission, which may include the (e.g., unique) WTRU ID. According to an embodiment, the WTRU 1110 may use its (e.g., unique) WTRU ID to obtain (e.g., generate) a WTRU-specific UL PRS. For example, the UL PRS may be obtained using a pseudo-random (PN) sequence, where the PN sequence generator may be initialized, for example, using the WTRU ID as one of the parameters. In another example, the UL PRS may be obtained, for example, by selecting a numerical sequence (such as, for example, but not limited to, a Zaddoff-Chu sequence) with good autocorrelation and cross-correlation properties and performing a binary operation, for example, XOR, between the selected numerical sequence and the WTRUID.

[0118] According to an embodiment, the WTRU 1110 may apply the indicated TA to its transmission (e.g., in the UL). According to an embodiment, the WTRU 1110 may repeat (e.g., be the same) UL PRS transmission 1118 N times (e.g., transmit N UL PRS repetitions, where N is an integer greater than 1), for example, as configured by the reference BS 1101 of granted resources. The number of repetitions may be selected to achieve a (e.g., desired) level of positioning accuracy.

[0119] According to an embodiment, the uplink transmission of the (e.g., unique) WTRU ID and UL PRS may be received by the reference BS 1101 and one or more neighboring BSs 1102. According to an embodiment, any number of neighboring BSs 1102 may be configured to receive the uplink transmission of the WTRU ID and UL PRS, for example, by the positioning server 1103. For example, after receiving a positioning preamble from the WTRU 1110, the reference BS 1101 may transmit 1130 an assigned temporary identifier (e.g., T-CRNTI or TP-RNTI) and UL configuration (associated with the WTRU ID and UL PRS) to the positioning server 1103, which may further transmit 1132 to the neighboring BSs 1102.

[0120] According to an embodiment, the reference BS 1101 and any number of configured neighbor BSs 1102, where uplink measurements may be performed, may extract a (e.g., unique) WTRU ID using a temporary WTRU identifier (e.g., any of T-CRNTI, TP-RNTI). According to an embodiment, the reference BS 1101 and any number of configured neighbor BSs 1102 may decode a WTRU-specific positioning reference signal using a (e.g., unique) WTRU ID. According to an embodiment, the reference BS 1101 and any number of configured neighbor BSs 1102 may perform measurements (e.g., any of RSRP and TOA) based on the decoded WTRU-specific positioning reference signal. According to an embodiment, the configuration of the measurements may be performed (e.g., determined and transmitted) by the positioning server 1103. According to an embodiment, the reference BS 1101 and any number of configured neighbor BSs 1102 may report 1140 the measurements with the (e.g., unique) WTRU ID to the positioning server 1103.

[0121] According to an embodiment, uplink transmissions of a reference signal (e.g., any of SRS, UL PRS, etc.) may be configured (e.g., periodic) to occur periodically with (e.g., specified, periodic) start and stop times. According to an embodiment, such (e.g., each) periodic occasion may include multiple transmissions of a reference signal (e.g., any of SRS, UL PRS, etc.) to achieve (e.g., a desired) measurement accuracy. According to an embodiment, at the end of (e.g., each) transmission burst including multiple reference signals constituting a single measurement, the reference BS 11101 may release 1136 the temporary identifier (e.g., any of T-CRNTI, TP-RNTI) assigned to the WTRU 1110 to a pool of available temporary identifiers. According to an embodiment, at the start of (e.g., the next periodic) uplink positioning reference signal burst transmission, the WTRU 1110 may transmit a positioning preamble and obtain a new temporary identifier.

[0122] According to an embodiment, the reference BS may optionally send an acknowledgement to the WTRU for which the measurement was recorded. The acknowledgement may be scrambled using the (e.g., unique) WTRU ID.

[0123] According to an embodiment, at a neighboring BS that may be configured by the positioning server to perform uplink measurements, the uplink measurements may be performed by a location measurement unit (LMU) integrated in the BS. According to an embodiment, the positioning server may store and / or update the positioning information of the WTRU using a (e.g., unique) WTRU ID.

[0124] An example of a WTRU procedure 1200 for performing uplink-based idle / inactive mode positioning is shown in FIG. 12. In step 1210, the WTRU may be configured with a set of positioning preambles. The configuration of the WTRU may be performed by transmitting configuration information (e.g., any of a set of positioning-specific preambles and a set of positioning-specific resources). According to an embodiment (not shown in FIG. 12), the WTRU may not receive any positioning configuration information (e.g., indicating any of a set of positioning-specific preambles and a set of positioning-specific resources). For example, the WTRU may use reserved (e.g., pre-assigned, pre-configured, default, etc.) positioning-specific preambles and / or resources. In step 1212, a change (e.g., fluctuation) in the cell's downlink measurements may be detected, indicating a change in the WTRU's location. In step 1212, periodic uplink-based positioning updates may occur. If any change in position is detected and a periodic uplink-based positioning update occurs, the WTRU may transmit (e.g., select) a positioning preamble on one or more time / frequency resources in step 1214. The WTRU may determine the RA-RNTI. In step 1216, the WTRU may wait (e.g., at least) a monitoring period of the PRAR window. In step 1218, the WTRU may detect a PRAR transmission. If no PRAR transmission is detected in step 1218 after the monitoring period, the WTRU may increase the transmit power by a (e.g., configurable) amount in step 1220 and proceed to step 1214. If a PRAR transmission is detected in step 1218 (e.g., within the PRAR window), the WTRU may extract any of the TA, TP-RNTI, and UL allocation from the PRAR in step 1222. In step 1224, the WTRU may send (eg, transmit) the WTRU ID (eg, Positioning-TMSI) scrambled with the TP-RNTI on the assigned UL resources.In step 1226, the WTRU may send (eg, transmit) a repetition of the WTRU positioning reference signal (eg, generated as a function of the WTRU ID) on the assigned resources.

[0125] According to an embodiment, two or more (several different) WTRUs can use the same preamble on the same PRACH resource for uplink-based positioning updates. Two or more WTRUs can receive the same PRAR message from the reference BS. Two or more WTRUs can transmit WTRU ID and ULPRS using the same resource. The reference BS and / or any number of neighboring BSs can decode (e.g., successfully) two or more WTRU IDs (using any of the assigned T-CRNTI, TP-RNTI) on the configured resource. According to an embodiment, any (e.g., each) BS can decode two or more WTRU IDs and can select one WTRU ID (e.g., randomly, any of the first decoded) to perform further measurements. According to an embodiment, any (e.g., each) BS can decode (e.g., WTRU-specific) positioning reference signals on the configured resource using the selected WTRU ID and can measure them.

[0126] An example of contention resolution in uplink-based idle / inactive mode positioning 1300 is shown in Figures 13A and 13B (collectively "Figure 13"). With reference to Figure 13, two WTRUs, namely WTRU1 and WTRU2, may select the same base station, BS1, and may transmit the same positioning preamble to BS1 using the same PRACH resource. Both the reference BS and the neighbor BS may select WTRU1 to perform measurements and may report the measurements to the positioning server.

[0127] As shown in FIG. 13A, WTRU1 and WTRU2 may receive either a periodic downlink synchronization signal, system information (e.g., a positioning-specific preamble) from either BS1 or BS2. WTRU1 and WTRU2 may perform downlink measurements 1312. As shown in FIG. 13, both WTRU1 and WTRU2 may select the same base station BS1 and may acquire (e.g., receive) a positioning preamble (and, e.g., additional (e.g., PRACH-related) information, etc.) 1314. Both WTRU1 and WTRU2 may initiate an uplink-based positioning update 1316 (e.g., based on the downlink measurements). Both WTRU1 and WTRU2 may select the same preamble and the same RACH resource to initiate a positioning update 1318. Both WTRU1 and WTRU2 may transmit the same (e.g., positioning) preamble 1320 over the same PRACH resource. Base station BS1 may assign 1322 a temporary identifier (one of T-CRNTI and TP-RNTI) and forward (e.g., transmit) 1324 the recipient WTRU ID and uplink configuration of the UL PRS. Base station BS1 may send a positioning update message 1325 to the positioning server. The positioning update message 1325 may include the temporary identifier (e.g., TP RNTI) and the uplink configuration. The positioning server may send a positioning request message 1326 to base station BS2. The positioning request message 1326 may include the temporary identifier (e.g., TP RNTI) and the recipient WTRU ID and uplink configuration of the UL PRS. The positioning server may send an acknowledgement message 1327 to acknowledge the positioning update message 1325.

[0128] As shown in FIG. 13B, base station BS1 may transmit a positioning RAR 1330 including the TA, T-CRNTI / TP-RNTI, and any of the UL configurations for transmitting the WTRU ID and UL PRS. The PRAR 1330 may be received by both WTRU1 and WTRU2. Both WTRU1 and WTRU2 may transmit their WTRU IDs scrambled 1332, for example, using the T-CRNTI (e.g., using the same time / frequency resources) on resources assigned to the PRAR. Base station BS1 may receive both WTRU IDs on the same time / frequency resources. Base station BS1 may decode (e.g., select) one of them (e.g., WTRU1) 1334. Base station BS2 may receive both WTRU IDs on the same resources. Base station BS2 may decode (e.g., select) one of them (e.g., WTRU1) 1336. Both WTRU1 and WTRU2 may transmit WTRU-specific positioning reference signals (UL PRS) 1338, 1339 on the same time / frequency resources. The UL PRS 1338, 1339 transmitted by both WTRU1 and WTRU2, respectively, may be different (e.g., each generated as a function of a WTRU ID (e.g., Positioning-TMSI) and may be received by both base stations BS1 and BS2 on the same time / frequency resources. Both base stations BS1, BS2 may decode and measure (e.g., only) the UL PRS of a selected WTRU (e.g., WTRU1) 1340. Both base stations BS1, BS2 may send measurement report messages 1342, 1343 including the WTRU ID of WTRU1 to the positioning server. Base stations BS1, BS2 may (optionally) send an acknowledgement message 1344 to WTRU1.

[0129] Example of uplink positioning reference signal using PRACH and PUSCH-beam-based system According to an embodiment, in case of beam-based transmission, the WTRU may be assigned (e.g., a list of) neighboring BSs (e.g., cell identities) on which uplink measurements may be performed. According to an embodiment, the uplink configuration (e.g., any of time / frequency resources, bandwidth, number of transmissions of UL PRS) for any (e.g., each) neighboring BS may be provided to the WTRU. According to an embodiment, the list of neighboring BSs with uplink configurations may be sent to the (e.g., requesting) WTRU by a reference BS (e.g., that may have received and detected a positioning-specific preamble from the requesting WTRU) in a PRAR message.

[0130] According to an embodiment, the reference BS may obtain the uplink configurations of the neighboring BSs from the positioning server. According to an embodiment, the reference BS may transmit angle of arrival (e.g., Rx beam identification) or angle of departure (e.g., Tx beam identification or SSB identification) information to the positioning server. According to an embodiment, the angle of arrival / angle of departure (e.g., beam identification or SSB identification) at the reference BS may be derived from the received positioning preamble of the requesting WTRU. According to an embodiment, the angle of arrival / angle of departure information from the reference BS may be used by the positioning server to allocate a list of neighboring BSs and their uplink configurations (e.g., time / frequency resources, bandwidth) to perform uplink positioning measurements of the requesting WTRU. According to an embodiment, the positioning server may request the neighboring BSs to transmit their scheduling configurations. According to an embodiment, the angle of arrival / angle of departure information from the reference BS may be used to derive the angle of arrival (e.g., Rx beam identification) at the neighboring BSs to receive the transmission of the requesting WTRU. According to an embodiment, the WTRU may report selected (e.g., best) beams (e.g., synchronization signal block (SSB) IDs) for one or more neighboring BSs (e.g., participating in uplink positioning measurements) to a reference BS. According to an embodiment, the WTRU may receive a message or command from a reference BS to report (e.g., selected, best) beams of one or more neighboring BSs. According to an embodiment, the WTRU may select (e.g., best) beams of different BSs based on its previous downlink measurements (e.g., measurements of downlink synchronization signals such as RSRP of SSBs). The reference BS may send information of selected (e.g., best) beams to a positioning server, which may forward it to the corresponding neighboring BSs. According to an embodiment, the positioning server may request the neighboring BSs to perform uplink measurements and report the results.

[0131] According to an embodiment, the WTRU may receive a list of neighboring BSs with uplink configurations according to the reference BS in the PRAR message. According to an embodiment, the requesting WTRU may send (e.g., transmit) its UL PRS using the uplink configuration received in the PRAR. According to an embodiment, the WTRU may select a set of neighboring BSs from the list of BSs provided (e.g., received) in the PRAR to send (e.g., transmit) its UL PRS. According to an embodiment, the WTRU may send (e.g., transmit) its UL PRS using the best beam for any (e.g., each) BS on the configured resources received in the PRAR.

[0132] Example of a one-message WTRU-specific reference signal using PRACH According to an embodiment, the WTRU may use (e.g., transmit) a (e.g., unique) preamble to perform uplink-based idle / inactive mode positioning. According to an embodiment, the (e.g., unique) preamble may be WTRU-specific, which may be assigned to the WTRU by the network (e.g., during the WTRU's RRC connected state) for transmitting the uplink-based idle / inactive mode positioning signal. According to an embodiment, the WTRU-specific preamble may be associated with a WTRU ID (e.g., any of S-TMSI, 5G-S-TMSI, Positioning-TMSI), which may be unique within a tracking region.

[0133] According to an embodiment, the WTRU may transmit a WTRU-specific preamble using one or more PRACH resources (e.g., time / frequency) of the BS. According to an embodiment, the RACH resources may be communicated (e.g., received) to the WTRU, e.g., in the system information. According to an embodiment, the WTRU may be assigned one or more specific time / frequency resources to send (e.g., transmit) a preamble to update its positioning information in idle / inactive mode. According to an embodiment, the network may, e.g., uniquely assign (e.g., specific) time / frequency resources to, e.g., one or more WTRUs in a (e.g., tracking) region. According to an embodiment, information of the specific time / frequency resources may be communicated to the WTRU, e.g., during a tracking region update procedure.

[0134] According to an embodiment, if the WTRU is configured to use a (e.g., unique) preamble, the WTRU-specific preamble configuration may be communicated (e.g., transmitted) by the positioning server to multiple BSs (e.g., within the WTRU's tracking area). According to an embodiment, if the WTRU is configured to send (e.g., transmit) a preamble using a specific time / frequency resource to update its positioning information in idle / inactive mode, the (e.g., specific) time / frequency resource configuration may be communicated by the positioning server to multiple BSs (e.g., within the WTRU's tracking area).

[0135] According to an embodiment, the WTRU may initiate an uplink-based positioning update, e.g., by transmitting a WTRU-specific preamble using one or more common PRACH resources and / or specific time / frequency resources, if configured. According to an embodiment, the WTRU may initiate an uplink-based positioning update, e.g., by transmitting a common PRACH or a positioning-specific preamble using one or more (e.g., specific) time / frequency resources.

[0136] According to an embodiment, following a WTRU transmission of one or more positioning preambles (e.g., either WTRU-specific and common), a BS that may detect the preamble and may be configured by the positioning server to perform uplink measurements may perform and report measurements to the positioning server.

[0137] Example of a one-message WTRU-specific reference signal using a PRACH beam-based system According to an embodiment, in case of beam-based transmission, the WTRU may use the best beam for any (e.g., each) BS to send (e.g., transmit) its WTRU-specific positioning preamble on the occasion of the RACH specific to each BS. According to an embodiment, the selection of the BS and the corresponding best beam for sending the WTRU-specific positioning preamble may be performed by the WTRU based on downlink measurements (e.g., measurements of a downlink synchronization signal such as RSRP of SSB). According to an embodiment, the time / frequency resources of any (e.g., each) selected BS may be communicated (e.g., received) to the WTRU, e.g., in the system information. According to an embodiment, the selection of the BS to send (e.g., transmit) the WTRU-specific positioning preamble may be communicated (e.g., received) to the WTRU, e.g., during a tracking area update procedure.

[0138] According to an embodiment, a WTRU may be assigned one or more specific time / frequency resources on any (e.g., each) BS for sending (e.g., transmitting) a preamble to update its positioning information in idle / inactive mode. According to an embodiment, a network may (e.g., uniquely) assign (e.g., specific) time / frequency resources to, for example, one or more WTRUs on any (e.g., each) BS in a tracking area. According to an embodiment, information of the specific time / frequency resources may be communicated to the WTRU, for example, during a tracking area update procedure. According to an embodiment, for any (e.g., each) BS, a WTRU may send (e.g., transmit) its one or more preambles using the specific time / frequency resources and best identified beam.

[0139] Example of a new physical channel for positioning According to an embodiment, the WTRU may transmit either a DL positioning measurement report and / or an RS for UL positioning measurements over a (e.g., dedicated) physical channel to perform positioning during an RRC idle / inactive mode. According to an embodiment, the positioning may be performed based on either an uplink signal and a downlink signal.

[0140] According to an embodiment, for downlink-based positioning, a WTRU in idle / inactive mode may perform positioning measurements (e.g., any of RSTD, OTDOA, etc.) on a (e.g., periodically timed) broadcast channel, such as any of SSB transmissions and reference signals (e.g., PRS) in NR. According to an embodiment, a WTRU in idle / inactive mode may report those measurements to a positioning server (e.g., E-SMLC), e.g., via a reference BS, e.g., using a new positioning physical random access channel (P-PRACH).

[0141] According to an embodiment, for uplink-based positioning, the WTRU may transmit a positioning signal (e.g., any of an RS, RACH preamble, synchronization signal, etc.) on a P-PRACH that may be monitored by a (e.g., local) BS, and the positioning measurement (e.g., UTDOA) may be forwarded to a positioning server (e.g., E-SMLC), for example, to determine the location of the WTRU.

[0142] Downlink-based positioning example According to an embodiment, the WTRU may transmit a positioning preamble within (e.g., assigned) time and frequency resources (e.g., one or more resource elements). While doing so, the WTRU may use the assigned positioning preamble. According to an embodiment, the positioning preamble may be obtained (e.g., constructed, calculated) using, for example, a numerical sequence having good autocorrelation and cross-correlation properties (e.g., without limitation, a Zaddoff-Chu sequence, etc.). According to an embodiment, the positioning preamble may be different from, and may use different time / frequency resources than, a RACH preamble used for any of initial access, cell reselection, etc.

[0143] According to an embodiment, the WTRU may use a (e.g., unique, same) positioning preamble within a transmission opportunity, which includes a set of contiguous time / frequency resources (e.g., positioning random access channel occasions (PROs)), which is identifiable even in the case of, for example, multiple simultaneous (e.g., separate) transmissions (e.g., multiple different transmissions occurring in the same time period). According to an embodiment, a (e.g., unique) positioning preamble may be assigned to the WTRU by the serving BS when the WTRU is in a connected state and may be unique within the cell. According to an embodiment, the positioning preamble may be associated with a preamble ID. According to an embodiment, the complete set of available positioning preambles may be divided into multiple groups (e.g., pools) to convey certain information to the reference BS. According to an embodiment, different time / frequency resources may be assigned to the WTRU to signal (e.g., indicate) a range of conditions to the reference BS.

[0144] According to an embodiment, after transmitting the positioning preamble, the WTRU may monitor the PDCCH for DCI scrambled using its own preamble ID. According to an embodiment, the DCI in the PDCCH may include resource allocation for the WTRU to transmit positioning information in a shared channel (e.g., PUSCH). According to an embodiment, the content of the DCI may include and / or indicate a temporary WTRU identifier (e.g., C-RNTI). According to an embodiment, the content of the DCI may include and / or indicate a modulation and coding scheme (MCS) assigned to the WTRU to use for uplink transmissions. According to an embodiment, the WTRU may append the positioning information (e.g., S-TMSI) to a (e.g., unique) identifier. According to an embodiment, the WTRU may append a (e.g., unique) identifier for the positioning information configuration. This message may be sent unencrypted or with an encryption key (e.g., either configured in RRC connected mode, pre-agreed, etc.).

[0145] According to an embodiment, if the WTRU does not receive a DCI scrambled with its own preamble ID within a (e.g., specific) period of time (e.g., based on a timer that starts after the positioning preamble is transmitted), the WTRU may abandon the current transmission process and wait for the next assigned positioning random access channel occasion (PRO).

[0146] According to embodiments, the WTRU may monitor a physical channel for an indication and / or determine that measurement reporting has been terminated by the network. According to embodiments, the indication may be sent to the WTRU, for example, over a dedicated physical channel while in RRC idle / inactive mode. According to embodiments, the WTRU may receive an indication from the network to initiate an RRC connection (e.g., paging, etc.) to terminate and / or reconfigure idle / inactive mode measurement reporting.

[0147] Uplink Synchronous Transmission Example According to an embodiment, a WTRU in idle / inactive mode and (e.g., periodically) monitoring a downlink broadcast channel (e.g., SSB transmissions) may determine the status of its own uplink synchronization and, for example, apply a timing advance to the positioning preamble transmission. According to an embodiment, UL synchronization may be configured via another channel (e.g., PRACH, etc.) and / or on the same channel as the previous occasion.

[0148] According to an embodiment, the WTRU may be configured by the network with a first (e.g., threshold) value for positioning measurements. According to an embodiment, if the downlink positioning measurements (e.g., OTDOA, RSTD, etc.) of a WTRU in idle / inactive mode differ from previous measurements by an amount less (e.g., smaller) than a (e.g., threshold) value, the WTRU may determine that it is uplink synchronized. According to an embodiment, if the WTRU is configured to perform multiple downlink-based positioning measurements associated with different BSs, the WTRU may determine that it is uplink synchronized with the serving cell (e.g., only) if all positioning measurements differ from previous values ​​by an amount less (e.g., smaller) than a (e.g., threshold) value.

[0149] According to an embodiment, the WTRU may be configured with multiple (e.g., threshold) values ​​for multiple positioning measurements. According to an embodiment, the WTRU may be configured with two (e.g., threshold) values ​​(one, e.g., for a reference cell and another, e.g., for a neighbor cell).

[0150] According to embodiments, the WTRU may be configured to perform measurements on multiple downlink transmissions (e.g., any of SSB, PRS, etc.) to obtain (achieve) a (e.g., desired) measurement accuracy. According to embodiments, the number and / or location of signals for measurements may be configured in the WTRU while in connected mode. According to embodiments, the WTRU may be configured to average multiple measurements from the same BS for reporting and comparison against a configured (e.g., threshold) value.

[0151] According to an embodiment, the WTRU may be configured with a second (e.g., threshold) value. According to an embodiment, if the difference between the WTRU's current positioning measurement (e.g., any of OTDOA, RSTD, etc.) and a previous measurement exceeds the first (e.g., threshold) value but is less than the second (e.g., threshold) value, the WTRU may determine (e.g., estimate) that its timing advance (TA) has changed by a first value (e.g., TA(current)=TA(previous)+1, TA(current)=TA(previous)−1). According to an embodiment, the WTRU may apply the new TA value to the uplink positioning preamble transmission.

[0152] According to an embodiment, the WTRU may determine that it is no longer uplink synchronized with the serving cell, for example, when (e.g., if) its current positioning measurements differ from previous measurements by more than (e.g., a maximum threshold) value, in which case the WTRU may not utilize (e.g., regular) PRO for positioning preamble transmissions.

[0153] According to an embodiment, WTRU transmissions in a normal PRO may be uplink synchronized and a small guard time (GT) may be configured by the network (e.g., GT=1*TA). Positioning preamble transmissions by the WTRU may have some timing misalignment due to some variations in the estimation of the relative position by the WTRU and small changes in the relative position and TA of the WTRU. According to an embodiment, configuring the PRO with a (e.g., small) GT may make it possible to avoid these variations in the estimation and breaking slot boundaries due to small relative position and TA changes. According to an embodiment, the GT may remain small (e.g., one or a few TAs), at least much smaller than the normal GT designed for large size cells (e.g., LTE GT=1032*TA).

[0154] Example of WTRU-specific positioning preamble reuse By assigning a different positioning preamble to each WTRU, the computational resources of the BS to perform cross-correlation for all possible preamble configurations may be large. By configuring the positioning preamble to be unique throughout a positioning region (e.g., a tracking region), the computational resources of the BS may be reduced. A positioning region may refer to an area where WTRUs in idle / inactive mode can use the same positioning preamble. Configuring a WTRU with a unique positioning preamble within a cell may reduce the search space of the BS within the positioning region, further reducing the computational resources of the BS to identify the WTRU transmitting the positioning preamble.

[0155] For WTRUs that may be configured to report periodic measurements in idle / inactive mode, preamble reuse in different PROs may enable further reduction of the preamble ID space. According to an embodiment, WTRUs that may transmit in the same PRO (e.g., only) depending on the configured positioning measurement reporting periodicity may be assigned a unique positioning preamble (the position preamble may only be unique in a given PRO). According to an embodiment, the positioning preamble may be reused (e.g., recycled) for the next group of WTRUs that may initiate a positioning measurement transmission procedure (e.g., transmit a positioning measurement report) using a subsequent PRO.

[0156] According to an embodiment, the WTRU may be configured for positioning measurements by a positioning server located in the network. According to an embodiment, the configuration may include any of the following: measurement type, measurement periodicity, measurement start time (e.g., in terms of frame, subframe, etc.), reporting periodicity, reporting start time, and a unique cell-specific positioning preamble ID. According to an embodiment, the WTRU may use the configured parameters to perform idle / inactive mode positioning measurements and reporting of measured quantities.

[0157] According to an embodiment, the (e.g., preferred) BS may determine a (e.g., unique) WTRU ID of the WTRU that transmitted the positioning preamble in the PRO based on the determination of the PRO identifier (e.g., the SFN where the PRO is located) and / or the WTRU positioning preamble ID. According to an embodiment, the (e.g., preferred) BS may transmit a DCI on a PDCCH scrambled using any combination of the cell ID and / or WTRU ID and the positioning preamble ID used by the WTRU. According to an embodiment, the DCI may include and / or indicate a resource allocation for the positioning report transmission.

[0158] Example of hierarchical division of positioning preamble According to an embodiment, the complete set of (e.g., available) positioning preambles may be divided into multiple (e.g., different) groups (e.g., pools) for use by WTRUs in idle / inactive mode to send positioning reports under different conditions, thereby allowing WTRUs in idle / inactive mode to implicitly signal different (e.g., preferred) BS conditions by selecting preambles from different (e.g., appropriate) groups.

[0159] According to an embodiment, one group of positioning preambles can be assigned to a BS (cell-specific positioning preambles). WTRUs can be assigned a positioning preamble ID before entering idle / inactive mode by their serving BS. For WTRUs in idle / inactive mode, the (e.g., preferred) BS can maintain a mapping between positioning preamble IDs and / or WTRU IDs. According to an embodiment, for periodic positioning reports, cell-specific positioning preambles can be reused by the BS across consecutive PROs to reduce the search space of the BS. In this case, the BS can maintain a mapping between WTRU IDs, positioning preamble IDs, and PRO identifiers (e.g., the SFN in which the PRO is located).

[0160] According to an embodiment, a (e.g., second) group of positioning preambles may be assigned for use by all BSs in a positioning area (PA common positioning preambles). A positioning area may include a group of BSs in an area. For example, a positioning area may be the same as a tracking area. According to an embodiment, a WTRU in idle / inactive mode may use this group of positioning preambles if either of the following first and second conditions are met: The first condition may include a positioning measurement that differs from a previous measurement by a value greater than a (e.g., given, maximum) value. The (e.g., given, maximum) value may be configurable and may have been previously configured by the network before the WTRU entered the idle / inactive mode. The second condition may include, for example, a determination by a WTRU in idle / inactive mode that its (e.g., preferred) BS may be updated based on the positioning measurement. A WTRU in idle / inactive mode may determine to update its (e.g., preferred) BS when, for example, the WTRU determines based on either its positioning measurements, RSRP / RSRQ measurements of SSB transmissions from multiple BSs, or that it is otherwise currently physically located near a BS different from the current (e.g., preferred) BS.

[0161] According to an embodiment, the PA-common positioning preamble may not be WTRU-specific. For example, a small group of such PA-common positioning preambles may be assigned for use by (e.g., all) WTRUs in a positioning area. If a WTRU uses a positioning preamble of this group, it may not be individually identifiable at the reference BS based on the positioning preamble alone. The WTRU may send its WTRU ID (e.g., S-TMSI, etc.) in a position report, e.g., a positioning message such as Positioning-Msg3 shown in FIG. 10 or FIG. 11, to resolve the ambiguity.

[0162] According to an embodiment, a WTRU in idle / inactive mode may be configured to use a positioning preamble for a PA common positioning preamble group, for example, selected (e.g., randomly, arbitrarily) from (e.g., available) preamble IDs. According to an embodiment, a WTRU in idle / inactive mode may be assigned a positioning preamble ID by the network before entering idle / inactive mode.

[0163] FIG. 14 illustrates an example of a procedure 1400 of positioning preamble selection by a WTRU to indicate a particular condition to a BS. With reference to FIG. 14, the WTRU may select a positioning preamble (e.g., one of cell-specific and PA-common positioning preambles) based on an estimate of a change in positioning measurements. According to an embodiment, different pools of preambles may be associated with different sizes of positioning reports. For example, a mapping may be created between a pool of preambles (e.g., available) and the size of the positioning report (e.g., to be requested / transmitted), e.g., a preamble from pool A for a short length positioning report, a preamble from pool B for a medium length positioning report, a preamble from pool C for a long length positioning report, etc. The WTRU may indicate the amount of resources requested for the positioning report by selecting (e.g., transmitting) a positioning preamble from the appropriate pool.

[0164] In step 1412, a WTRU in connected state may be configured with either a PA-common and an assigned cell-specific positioning preamble. In step 1414, the WTRU may be configured with (e.g., different periodic) resources for either the PA-common preamble, the short positioning report indication, or the long positioning report indication. In step 1416, the WTRU may be configured with a positioning measurement change threshold to trigger the use of the PA-common preamble. In step 1418, the WTRU may enter an idle / inactive state. In step 1420, it may be determined whether the change in the WTRU positioning measurements is greater than a (e.g., configured) threshold. If the change in the WTRU positioning measurements is greater than a (e.g., configured) threshold, the WTRU may transmit a PA-common positioning preamble in resources reserved for that purpose in step 1424. Otherwise (e.g., if the change in the WTRU positioning measurements is less than a (e.g., configured) threshold), it may be determined in step 1422 whether it is time to transmit a periodic positioning report. If it is time to send a periodic positioning report, it may be determined whether the WTRU may send a short positioning report in step 1426. If the WTRU wants to send a short positioning report, the WTRU may send an assigned cell-specific positioning preamble in resources reserved to indicate a short positioning report in step 1428. If the WTRU does not want to send a short positioning report, the WTRU may send an assigned cell-specific positioning preamble in resources reserved to indicate a long positioning report in step 1430. After sending the assigned cell-specific positioning preamble, the WTRU may monitor the PDCCH for the BS's response in step 1430.

[0165] FIG. 15 illustrates an example procedure 1500 of WTRU operation for idle / inactive mode positioning report transmission in idle / inactive mode using a new physical channel. With reference to FIG. 15, the WTRU may transmit an unscheduled report upon sensing that a positioning measurement has changed by more than a value (e.g., a pre-configured threshold) relative to a previous measurement. According to the illustrated example, the WTRU may be configured for periodic positioning reports.

[0166] In step 1512, the WTRU may start a response timer after transmitting the positioning preamble. In step 1514, the WTRU may monitor the PDCCH for a (e.g., cell) response. In step 1518, it may be determined whether the DCI is scrambled with the WTRU's positioning preamble ID and whether the cell ID is detected. If the DCI is scrambled with the WTRU's positioning preamble ID and the cell ID is detected, in step 1522, the WTRU may read the DCI to obtain a resource allocation for transmitting a positioning report. In step 1524, it may be determined whether the WTRU previously used a PA common preamble. If the WTRU did not previously use a PA common preamble, in step 1528, it may be determined whether the WTRU sent a cell-specific positioning preamble using a short reporting resource. If the WTRU transmitted a cell-specific positioning preamble using a short reporting resource, in step 1530, the WTRU may transmit periodic short positioning reports on the allocated resources. Otherwise, in step 1532, the WTRU may transmit a periodic long positioning report in the assigned resources. If, in step 1524, it is determined that the WTRU previously used a PA common preamble, in step 1526, the WTRU may transmit an aperiodic positioning report including the WTRU ID in the assigned resources. In step 1530, it may be determined whether periodic positioning reporting is configured. If periodic positioning reporting is set, in step 1534, the WTRU may wait until the next periodic reporting occasion. Otherwise, in step 1536, the WTRU may send (e.g., attempt) a positioning report (e.g., again) after a (e.g., minimum) retransmission interval if the (e.g., maximum) number of retransmissions is not exceeded. If, in step 1518, it is determined that the DCI is not scrambled with the WTRU's positioning preamble ID and / or the cell ID is not detected, in step 1520, it may be determined whether the response timer has expired.If the response timer has not expired, the WTRU may wait until the end of the next subframe in step 1516. Otherwise, the procedure may proceed to step 1530.

[0167] FIG. 16 illustrates an example of a procedure 1600 for idle / inactive mode positioning measurements. In step 1612, the WTRU may be configured to perform positioning measurements in any of idle and inactive modes. In step 1614, the WTRU may receive a signal while the WTRU is in any of idle and inactive modes. In one embodiment, the received signal may be any of PSS, SSS, DMRS, CRS, and PRS. In step 1616, at least one positioning measurement parameter may be obtained based on the received signal. In one embodiment, the at least one positioning measurement parameter may be any of RTT, AOA, and RSTD.

[0168] FIG. 17 illustrates an example of a procedure 1700 for idle / inactive mode positioning measurement reporting. In step 1712, the WTRU may be configured to perform positioning measurements in either idle mode or inactive mode. In step 1714, the WTRU may be configured to transmit a positioning measurement report in either idle mode or inactive mode. In one embodiment, the positioning measurement report may include at least one positioning measurement parameter. In step 1716, the WTRU may transmit a positioning measurement report in a RACH. In one embodiment, the positioning measurement report may be transmitted within a RACH preamble. In one embodiment, the positioning measurement report may be transmitted appended to the RACH preamble.

[0169] FIG. 18 illustrates an example of a procedure 1800 for idle / inactive mode positioning measurement reporting. In step 1812, the WTRU may be configured to perform positioning measurements in any of idle and inactive modes. In step 1814, the WTRU may be configured to transmit a positioning measurement report in any of idle and inactive modes. In step 1816, the WTRU may transmit information on the RACH indicating an intention to transmit a positioning measurement report. In step 1818, the WTRU may receive an RAR indicating an uplink reporting resource. In step 1820, the WTRU may transmit a positioning measurement report according to the uplink reporting resource. According to an embodiment, an apparatus including a circuit including any of a transmitter, a receiver, a processor, and a memory may be configured to perform a method according to any of FIG. 16, FIG. 17, and FIG. 18. In an embodiment, the apparatus may be any of a WTRU and a base station. According to an embodiment, an apparatus including a circuit including any of a transmitter, a receiver, a processor, and a memory may be configured to perform a method including complementary functions described in any of Figures 16, 17, and 18. According to an embodiment, any of the non-transitory computer-readable storage medium and computer programs may include instructions that, when executed by a computer, cause the computer to perform a method according to any of Figures 16, 17, and 18. According to an embodiment, any of the non-transitory computer-readable storage medium and computer programs may include instructions that, when executed by a computer, cause the computer to perform a method including complementary functions to functions described in any of Figures 16, 17, and 18.

[0170] FIG. 19 illustrates an example of a procedure 1900 for uplink-based positioning in a WTRU. In step 1912, the WTRU may transmit a positioning request. In step 1914, the WTRU may receive a PRAR indicating assigned resources for transmitting repetitions of an uplink positioning reference signal. In step 1916, the WTRU may transmit repetitions of the UL PRS on the assigned resources. In one embodiment, the WTRU may be in an idle mode and an inactive mode. In one embodiment, the positioning request transmission may be a transmission of a positioning specific preamble (e.g., in any resource) and a transmission in (e.g., any) positioning specific resource. In one embodiment, the WTRU may be configured (e.g., receive configuration information) with a set of positioning specific preambles, a set of positioning specific resources, a periodicity for transmitting the positioning request, and a start time and a stop time for transmitting the positioning request. In one embodiment, the positioning request may be transmitted after expiration of a timer and receipt of a downlink reference signal indicating a positioning change of the WTRU. In one embodiment, the positioning RAR may further include information indicating any of the following: a timing advance, a temporary WTRU ID, a bandwidth portion, a set of resources for transmitting the WTRU ID, and an uplink configuration for transmitting a repetition of the UL PRS. In one embodiment, the positioning RAR may further include several repetition transmissions of the UL PRS. In one embodiment, the temporary WTRU identifier may be any of the T-CRNTI and the TP-RNTI. In one embodiment, the WTRU ID may be any of the S-TMSI, the 5G-S-TMSI, and the Positioning-TMSI. In one embodiment, the UL PRS may be based on the WTRU ID. In one embodiment, the temporary WTRU identifier may be used to scramble the WTRU ID.

[0171] 20 illustrates an example of a procedure 2000 for uplink-based positioning in a base station. In step 2012, the BS may receive a positioning request from a WTRU. In step 2014, the BS may transmit a positioning RAR indicating allocated resources for the WTRU to transmit repetitions of the UL PRS. In step 2016, the BS may receive at least one UL PRS from the WTRU. In step 2018, the BS may obtain the location of the WTRU based on the received at least one UL PRS.

[0172] According to an embodiment, an apparatus including a circuit including any of a transmitter, a receiver, a processor, and a memory may be configured to perform the method according to any of Figures 19 and 20. In an embodiment, the apparatus may be any of a WTRU and a base station. According to an embodiment, any of a non-transitory computer-readable storage medium and a computer program may include instructions that, when executed by a computer, cause the computer to perform the method according to any of Figures 19 and 20.

[0173] conclusion Although the features and elements are described above in certain combinations, one skilled in the art will understand that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware embodied in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of 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, optical media such as CD-ROM disks, digital versatile disks (DVDs), and the like. A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

[0174] Although not explicitly described, the present embodiments may be used in any combination or subcombination. For example, the present principles are not limited to the variations described, and any arrangement of the variations and embodiments may be used. Furthermore, the present principles are not limited to the channel access methods described, and any other type of channel access method is compatible with the present principles.

[0175] Furthermore, any features, variations or embodiments described in the methods are compatible with an apparatus device including means for processing the disclosed methods, a device including a processor configured to process the disclosed methods, a computer program product including program code instructions, and a non-transitory computer readable storage medium storing program instructions.

[0176] Although the features and elements are described above in certain combinations, one skilled in the art will understand that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware embodied 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, optical media such as CD-ROM disks, digital versatile disks (DVDs), and the like. A processor in association with software may be used to implement a radio frequency transceiver for use in the WTRU 102, UE, terminal, base station, RNC, or any host computer.

[0177] Additionally, in the above embodiments, processing platforms, computing systems, controllers, and other devices including processors are described. These devices may include at least one central processing unit ("CPU") and memory. In accordance with the practices of those skilled in the art of computer programming, references to acts and symbolic representations of operations or instructions may be performed by various CPUs and memories. Such acts and operations or instructions may be referred to as being "executed," "executed by a computer," or "executed by a CPU."

[0178] Those skilled in the art will appreciate that the acts and symbolically represented operations or instructions include the manipulation of electrical signals by a CPU. The electrical system represents the data bits which may cause the resulting transformation or reduction of the electrical signals and the maintenance of the data bits in memory locations within the memory system, thereby reconfiguring or altering the operation of the CPU and other processing of the signals. The memory locations in which the data bits are maintained are physical locations that have specific electrical, magnetic, optical, or organic properties that correspond to or represent the data bits. It should be understood that representative embodiments are not limited to the above platforms or CPUs, and that other platforms and CPUs may support the provided methods.

[0179] 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 a CPU. The computer readable media may include cooperative or interconnected computer readable media that resides exclusively on a processing system or that is distributed among multiple interconnected processing systems that may be local or remote to a processing system. It will be appreciated that representative embodiments are not limited to the above memories, and that other platforms and memories may support the described methods.

[0180] In an example 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 a mobile unit, a network element, and / or any other computing device.

[0181] There is little difference between hardware and software implementations of aspects of the system. The use of hardware or software is generally (though not always, e.g., in that the choice between hardware and software may be significant in certain contexts) a design choice that represents a tradeoff between cost and efficiency. There may be a variety of vehicles (e.g., hardware, software, and / or firmware) in which the processes and / or systems and / or other technologies described herein may be affected, and the preferred vehicle may vary depending on the context in which the processes and / or systems and / or other technologies are being deployed. For example, if an implementer determines that speed and accuracy are paramount, the implementer may select a primarily hardware and / or firmware vehicle. If flexibility is paramount, the implementer may select a primarily software implementation. Alternatively, the implementer may select some combination of hardware, software, and / or firmware.

[0182] The foregoing detailed description illustrates various embodiments of devices and / or processes through the use of block diagrams, flow charts, and / or examples. To the extent that such block diagrams, flow charts, and / or examples include one or more functions and / or operations, it will be understood by those skilled in the art that each function and / or operation in such block diagrams, flow charts, or examples can be individually and / or collectively implemented by a wide range of hardware, software, firmware, or substantially any combination thereof. Suitable processors include, by way of example, general purpose processors, special purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application specific integrated circuits (ASICs), application specific standard products (ASSPs), field programmable gate array (FPGA) circuits, any other type of integrated circuit (IC), and / or state machines.

[0183] Although features and elements are provided above in specific combinations, one skilled in the art will understand that each feature or element can be used alone or in any combination with other features and elements. The present disclosure is not limited with respect to the specific embodiments described in this application, which are intended as illustrations of various aspects. As will be apparent to those skilled in the art, many variations and modifications can be made without departing from the spirit and scope of the present disclosure. No element, act, or instruction used in the description of this application should be construed as critical or essential to the invention unless expressly provided as such. In addition to the methods and devices recited herein, functionally equivalent methods and devices within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description. Such variations and modifications are intended to be within the scope of the appended claims. The present disclosure should be limited only by the terms of the appended claims, and the full scope of equivalents to which such claims are entitled. It is understood that this disclosure is not limited to any particular method or system.

[0184] It should also be understood that the terminology used herein is merely for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the terms "station" and its abbreviation "STA", "user equipment" and its abbreviation "UE" when referred to herein may mean (i) a wireless transmit and / or receive unit (WTRU) as described in detail, (ii) any of some embodiments of a WTRU as described in detail, (iii) a wireless and / or wired (e.g., tetherable) device configured with some or all of the structure and functionality of a WTRU, particularly as described in detail, (iii) a wireless and / or wired device configured with less than all of the structure and functionality of a WTRU, as described in detail, or (iv) others. Details of an exemplary WTRU that may represent any UE listed herein are provided below with respect to FIGS. 1A-1D.

[0185] In certain representative embodiments, some portions of the subject matter described herein may be implemented via application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), and / or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein may be equivalently implemented, in whole or in part, as one or more computer programs running on one or more computers (e.g., one or more programs running on one or more computer systems), one or more programs running on one or more processors (e.g., one or more programs running on one or more microcomputers), firmware, or virtually any combination thereof, and that designing circuitry and / or writing code for the software and / or firmware is within the skill of those skilled in the art in light of this disclosure. In addition, those skilled in the art will understand that the mechanisms of the subject matter described herein may be distributed as program products in various forms, and that the exemplary embodiments of the subject matter described herein apply regardless of the particular type of signal-bearing medium used to actually perform the distribution. Examples of signal bearing media include, but are not limited to: recordable type media such as floppy disks, hard disk drives, CDs, DVDs, digital tape, computer memory, etc., and transmission type media such as digital and / or analog communications media (e.g., fiber optic cables, wave guides, wired communications links, wireless communications links, etc.).

[0186] The subject matter described herein may depict different components that are included in or connected with different other components. It should be understood that such depicted architectures are merely examples, and that in fact many other architectures that achieve the same functionality may be implemented. In a conceptual sense, an arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality can be achieved. Thus, any two components herein that are combined to achieve a particular functionality may be considered to be "associated" with each other such that the desired functionality is achieved, regardless of the architecture or intermediate components. Similarly, any two components so associated may also be considered to be "operably connected" or "operably coupled" with each other to achieve the desired functionality, and any two components that may be so associated may also be considered to be "operably coupled" with each other to achieve the desired functionality. Specific examples of operably coupleable include, but are not limited to, physically coupleable and / or physically interacting components and / or wirelessly interacting and / or wirelessly interacting components and / or logically interacting and / or logically interacting components.

[0187] With respect to the use of virtually any plural and / or singular term herein, those of skill in the art may translate from the plural to the singular and / or from the singular to the plural as appropriate to the context and / or application. For clarity, various singular / plural permutations may be expressly set forth herein.

[0188] In general, it will be understood by those skilled in the art that the terms used herein, and particularly in the appended claims (e.g., the body 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 "includes" should be interpreted as "includes but is not limited to," etc.). Where a particular number of introduced claims are intended, such intent will be expressly set forth in the claim, and in the absence of such a statement, it will be further understood by those skilled in the art that no such intent exists. For example, where only one item is intended, the term "single" or similar language may be used. To aid in understanding, the following appended claims and / or description of this specification may include the use of the introductory phrases "at least one" and "one or more" to introduce the recitation of claims. However, the use of such phrases should not be construed as meaning that introducing a claim recitation with the indefinite article "a" or "an" limits any particular claim containing such an introduced claim recitation to embodiments including only one, even if the same claim includes the introductory phrase "one or more" or "at least one" and an indefinite article 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 applies to the use of definite articles used to introduce claim recitations.In addition, even if a particular number of an introduced claim recitation is explicitly recited, one skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation "two recitations" without other modifiers means at least two recitations, or more than two recitations).

[0189] Furthermore, where there is a convention similar to "at least one of A, B, and C, etc.", such a configuration is generally intended in the sense that a person skilled in the art would understand the convention (e.g., "a system having at least one of A, B, and C" includes, but is not limited to, a system having only A, a system having only B, a system having only C, a system having both A and B, a system having both A and C, a system having both B and C, and / or a system having both A, B, and C, etc.). Furthermore, where there is a convention similar to "at least one of A, B, or C, etc.", such a configuration is generally intended in the sense that a person skilled in the art would understand the convention (e.g., "a system having at least one of A, B, or C" includes, but is not limited to, a system having only A, a system having only B, a system having only C, a system having both A and B, a system having both A and C, a system having both B and C, and / or a system having both A, B, and C, etc.). Those skilled in the art will further appreciate that any disjunctive word and / or phrase, whether in the specification, claims, or drawings, that presents substantially two or more alternative terms, should be understood to contemplate the possibility of including either one term, either the other term, or both terms. For example, the phrase "A or B" will be understood to include the possibility of "A" or "B" or "A and B." Additionally, as used herein, the term "any" followed by a list of a plurality of items and / or a plurality of categories of items is intended to include "any," "any combination," "any plurality of," and / or "any combination of the plurality of items and / or categories of items, either individually or in combination with other items and / or items of other categories." Additionally, as used herein, the term "set" or "group" is intended to include any number of items, including zero. Additionally, as used herein, the term "number" is intended to include any number, including zero.

[0190] Additionally, when features or aspects of the disclosure are described in terms of a Markush group, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual members or subgroups of members of the Markush group.

[0191] As will be appreciated by those skilled in the art, in terms of providing a written description, all ranges disclosed herein encompass any and all possible subranges and combinations of subranges thereof. Any range described can be readily recognized as fully describing the same range and allowing it to be broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third, upper third, etc. As will be appreciated by those skilled in the art, all language such as "up to," "at least," "greater than," "less than," etc. includes the cited number and refers to a range that can then be broken down into smaller ranges as described above. Finally, as will be appreciated by those skilled in the art, a range includes each individual member. Thus, for example, a group having 1 to 3 cells refers to a group having 1, 2, or 3 cells. Similarly, a group having 1 to 5 cells refers to a group having 1, 2, 3, 4, or 5 cells, and so forth.

[0192] Moreover, the claims should not be construed as limited to the order or elements provided unless so stated. In addition, the use of the term "means for" in any claim is intended to invoke 35 U.S.C. ...

[0193] A processor in association with software may be used to implement a radio frequency transceiver for use in a wireless transmit / receive unit (WTRU), user equipment (UE), terminal, base station, mobility management entity (MME) or evolved packet core (EPC), or any host computer. The WTRU may be used in combination with hardware and / or software including software defined radios (SDRs) and modules implemented in other components, such as cameras, video camera modules, videophones, speakerphones, vibration devices, speakers, microphones, television transceivers, hands-free headsets, keyboards, Bluetooth modules, frequency modulation (FM) radio units, near field communications (NFC) modules, liquid crystal display (LCD) display units, organic light emitting diode (OLED) display units, digital music players, media players, video game player modules, Internet browsers, and / or wireless local area network (WLAN) or ultra-wideband (UWB) modules.

[0194] Although the invention has been described with respect to a communications system, it is contemplated that the system may be implemented in software on a microprocessor / general purpose computer (not shown). In particular embodiments, one or more of the functions of the various components may be implemented in software controlling a general purpose computer.

[0195] In addition, although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown, but rather various modifications in the details may be made within the scope and range of equivalents of the claims without departing from the invention.

[0196] Throughout this disclosure, those skilled in the art will understand that certain representative embodiments may be used in the alternative or in combination with other representative embodiments.

[0197] Although the features and elements are described above in certain combinations, one skilled in the art will understand that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware embodied 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, optical media such as CD-ROM disks, digital versatile disks (DVDs), and the like. A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

[0198] Additionally, in the above embodiments, processing platforms, computing systems, controllers, and other devices including processors are described. These devices may include at least one central processing unit ("CPU") and memory. In accordance with the practices of those skilled in the art of computer programming, references to acts and symbolic representations of operations or instructions may be performed by various CPUs and memories. Such acts and operations or instructions may be referred to as being "executed," "executed by a computer," or "executed by a CPU."

[0199] Those skilled 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 the data bits which may cause the transformation or reduction of the resulting electrical signals and the maintenance of the data bits in memory locations within the memory system, thereby reconfiguring or altering the operation of the CPU and other processing of the signals. The memory locations in which the data bits are maintained are physical locations that have particular electrical, magnetic, optical, or organic properties that correspond to or represent the data bits.

[0200] 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 a CPU. The computer readable media may include cooperative or interconnected computer readable media that resides exclusively on a processing system or that is distributed among multiple interconnected processing systems that may be local or remote to a processing system. It will be appreciated that representative embodiments are not limited to the above memories, and that other platforms and memories may support the described methods.

[0201] Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), an application specific standard product (ASSP), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), and / or a state machine.

[0202] Although the invention has been described with respect to a communications system, it is contemplated that the system may be implemented in software on a microprocessor / general purpose computer (not shown). In particular embodiments, one or more of the functions of the various components may be implemented in software controlling a general purpose computer.

[0203] In addition, although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown, but rather various modifications in the details may be made within the scope and range of equivalents of the claims without departing from the invention.

Claims

1. 1. A method implemented in a wireless transmit / receive unit (WTRU), comprising: Transmitting a positioning request; receiving a positioning random access response (positioning RAR) indicating allocated resources for transmitting repetitions of an uplink positioning reference signal (UL PRS); transmitting repetitions of the UL PRS on the assigned resources.

2. The method of claim 1 , wherein the WTRU is in one of an idle mode and an inactive mode.

3. The method according to any one of claims 1 to 2, wherein transmitting the positioning request comprises any of transmitting a positioning specific preamble and transmitting on a positioning specific resource.

4. The method of any one of claims 1 to 3, wherein the WTRU is configured with any of a set of positioning specific preambles and a set of positioning specific resources.

5. The method of any one of claims 1 to 4, wherein the WTRU is configured with a periodicity for transmitting positioning requests.

6. The method of any one of claims 1 to 5, wherein the WTRU is configured with periodic start and stop times for transmitting positioning requests.

7. The method according to any one of claims 1 to 6, wherein the positioning request is sent after expiry of a timer.

8. The method of any one of claims 1 to 7, wherein the positioning request is transmitted after receipt of a downlink reference signal indicating a change in the WTRU's positioning.

9. The method according to any one of claims 1 to 8, wherein the positioning RAR further includes information indicating any of the following: a timing advance, a temporary WTRU identifier, a bandwidth portion, a set of resources for transmitting a WTRU identifier, and an uplink configuration for transmitting a repetition of the UL PRS.

10. The method of claim 9 , wherein the positioning RAR further comprises several repeated transmissions of a UL PRS.

11. 10. The method of claim 9, wherein the temporary WTRU identifier is one of a Temporary Cell Radio Network Temporary Identifier (T-CRNTI) and a Temporary Positioning Radio Network Temporary Identifier (TP-RNTI).

12. The method of any one of claims 9 to 11, wherein the WTRU identifier is one of a System Architecture Evolution Temporary Mobile Subscription Identifier (S-TMSI), a 5G-S-TMSI, and a Positioning-TMSI.

13. The method of any one of claims 9 to 12, wherein the UL PRS is based on the WTRU identifier.

14. The method of any one of claims 9 to 13, wherein the temporary WTRU identifier is used to scramble the WTRU identifier.

15. 1. A method comprising: receiving a positioning request from a wireless transmit / receive unit (WTRU); transmitting a positioning random access response (positioning RAR) indicating allocated resources for the WTRU to transmit repetitions of an uplink positioning reference signal (UL PRS); receiving at least one UL PRS from the WTRU; and obtaining a location of the WTRU based on the received at least one UL PRS.

16. A computer readable storage medium comprising instructions which, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 15.

17. A computer program comprising instructions which, when executed by a computer, cause the computer to carry out the method according to any one of claims 1 to 15.

18. An apparatus including a circuit, the apparatus including any of a transmitter, a receiver, a processor, and a memory; receiving a positioning request from a wireless transmit / receive unit (WTRU); transmitting a positioning random access response (positioning RAR) indicating allocated resources for the WTRU to transmit repetitions of an uplink positioning reference signal (UL PRS); receiving at least one UL PRS from the WTRU; and obtaining a location of the WTRU based on the received at least one UL PRS.

19. The apparatus of claim 18 , wherein the apparatus is a base station.

20. The apparatus of claim 18 or 19, wherein the circuitry is configured to transmit configuration information to the WTRU indicating one of a set of positioning specific preambles and a set of positioning specific resources.

21. An apparatus including a circuit, the apparatus including any of a transmitter, a receiver, a processor, and a memory; Transmitting a positioning request; receiving a positioning random access response (positioning RAR) indicating allocated resources for transmitting repetitions of an uplink positioning reference signal (UL PRS); transmitting repetitions of the UL PRS on the assigned resources.

22. 22. The device of claim 21, wherein the device is in one of an idle mode and an inactive mode.

23. The apparatus of any one of claims 21 to 22, wherein transmitting the positioning request comprises any of transmitting a positioning specific preamble and transmitting on a positioning specific resource.

24. The apparatus of any one of claims 21 to 23, further configured to receive configuration information indicating any of a set of positioning specific preambles and a set of positioning specific resources.

25. The apparatus of any one of claims 21 to 24, further configured to receive configuration information indicating a periodicity for transmitting positioning requests.

26. The apparatus of any one of claims 21 to 25, further configured to receive configuration information indicating periodic start and stop times for transmitting positioning requests.

27. The apparatus of any one of claims 21 to 26, further configured to transmit the positioning request after expiration of a timer.

28. The apparatus of any one of claims 21 to 27, further configured to transmit the positioning request after receiving a downlink reference signal indicating a positioning change of the apparatus.

29. The apparatus according to any one of claims 21 to 28, wherein the positioning RAR further includes information indicating any of a timing advance, a temporary WTRU identifier, a bandwidth portion, a set of resources for transmitting a WTRU identifier, and an uplink configuration for transmitting repetitions of the UL PRS.

30. The apparatus of claim 29 , wherein the positioning RAR further comprises several repeated transmissions of a UL PRS.

31. 30. The apparatus of claim 29, wherein the temporary WTRU identifier is one of a Temporary Cell Radio Network Temporary Identifier (T-CRNTI) and a Temporary Positioning Radio Network Temporary Identifier (TP-RNTI).

32. The apparatus of any one of claims 29 to 31, wherein the WTRU identifier is one of a System Architecture Evolution Temporary Mobile Subscription Identifier (S-TMSI), a 5G-S-TMSI, and a Positioning-TMSI.

33. The apparatus of any one of claims 29 to 32, wherein the UL PRS is based on the WTRU identifier.

34. The apparatus of any one of claims 29 to 33, wherein the temporary WTRU identifier is used to scramble the WTRU identifier.

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