Uplink timing and timing advance determination for area-specific sounding reference signal (SRS) for positioning

Abstract

Techniques for wireless communication are disclosed. In an aspect, a user equipment (UE), when operating in a radio resource control (RRC) disconnected state and when residing on a first cell of a first sounding reference signal (SRS) validity region, transmits one or more region-specific SRSs, where the one or more region-specific SRSs are associated with a first uplink timing advance (TA); and when operating in the RRC non-connected state and when residing on the first cell of the first SRS validity region, the user equipment (UE) transmitting one or more physical layer uplink channels, where the one or more physical layer uplink channels are associated with a second uplink TA.

Description

Cross Reference to Related Applications

[0001] This patent application claims priority to Greek Patent Application No. 20230100289, filed April 5, 2023, entitled “UPLINK TIMING AND TIMING ADVANCE DETERMINATION FOR AREA-SPECIFIC SOUNDING REFERENCE SIGNALS (SRS) FOR POSITIONING,” which is assigned to the assignee of the present application and is hereby expressly incorporated by reference in its entirety. TECHNICAL FIELD

[0002] Aspects of the disclosure relate generally to wireless communication. BACKGROUND

[0003] Wireless communication systems have developed through several generations, including first-generation analog wireless telephones (1G), second-generation (2G) digital wireless telephones (including 2.5G and 2.75G networks), third-generation (3G) high speed data, Internet-capable wireless systems and fourth-generation (4G) long-term evolution (LTE) or WiMax systems. There are numerous types of wireless communication systems in current use, including cellular and personal communications service (PCS) systems. Examples of known cellular systems include the cellular analog advanced mobile phone system (AMPS), and digital cellular systems based on code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), the global system for mobile communications (GSM), etc.

[0004] The fifth generation (5G) wireless standard, referred to as New Radio (NR), enables higher data transfer speeds, greater numbers of connections, and better coverage than previous standards. According to the Next Generation Mobile Networks Alliance, 5G technology should provide bitrates on the order of 100 megabits per second (Mbps) to one gigabit per second (Gbps), with reduced latency and increased efficiency, compared to previous standards, to enable a wide range of new applications and services that were not possible with earlier wireless systems. These enhancements and improvements should enable 5G wireless technology to deliver a rich user experience for SUMMARY

[0005] The following presents a simplified summary of aspects related to one or more aspects disclosed herein. Thus, the following summary should not be considered an extensive overview relating to all contemplated aspects, nor should the following summary be considered to identify key or critical elements relating to all contemplated aspects or to delineate the scope associated with any particular aspect. Accordingly, the following summary has the sole purpose to present certain concepts relating to one or more aspects disclosed herein in a simplified form to precede the detailed description presented below.

[0006] In an aspect, a method of wireless communication performed by a user equipment (UE) includes receiving one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and transmitting one or more first zone-specific SRS based on the one or more SRS configurations and an uplink timing of the UE when operating in a radio resource control (RRC) inactive state and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone associated with the UE within which the UE is camped; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell based on a random access procedure with the cell on which the UE is camped, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0007] In an aspect, a method of wireless communication performed by a user equipment (UE) includes transmitting one or more region-specific sounding reference signal (SRS) when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone, wherein the one or more region-specific SRS are associated with a first uplink timing advance (TA), and transmitting one or more physical layer uplink channels when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0008] In an aspect, a user equipment (UE) includes one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: receive, via the one or more transceivers, one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, transmit, via the one or more transceivers, one or more first region-specific SRS based on the one or more SRS configurations and an uplink timing of the UE, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone associated with the UE; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell based on a random access procedure with the cell on which the UE is camped, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform short data transmission (SDT), non-region-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0009] In an aspect, a user equipment (UE) includes one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: transmit, via the one or more transceivers, one or more region-specific sounding reference signal (SRS) when operating in a radio resource control (RRC) -connected state and when camped on a first cell of a first SRS validity zone, wherein the one or more region-specific SRS are associated with a first uplink timing advance (TA); and transmit, via the one or more transceivers, one or more physical layer uplink channels when operating in the RRC-connected state and when camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0010] In an aspect, a user equipment (UE) includes means for receiving one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and means for transmitting, when operating in a radio resource control (RRC) -connected state and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, one or more first region-specific SRS based on the one or more SRS configurations and an uplink timing of the UE, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone associated with the UE; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell based on a random access procedure with the cell on which the UE is camped, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform short data transmission (SDT), non-region-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0011] In an aspect, a user equipment (UE) includes means for transmitting one or more region-specific sounding reference signal (SRS) when operating in a radio resource control (RRC) idle mode and when camped on a first cell of a first SRS validity zone, wherein the one or more region-specific SRS are associated with a first uplink timing advance (TA); and means for transmitting one or more physical layer uplink channels when operating in the RRC idle mode and when camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0012] In an aspect, a non-transitory computer-readable medium stores computer- executable instructions that, when executed by a user equipment (UE), cause the UE to: receive one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and transmit one or more first region-specific SRS based on the one or more SRS configurations and an uplink timing of the UE when operating in a radio resource control (RRC) idle mode and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone with which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure of the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform short data transmission (SDT), non-region-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0013] In an aspect, a non-transitory computer-readable medium stores computer- executable instructions that, when executed by a user equipment (UE), cause the UE to: transmit one or more zone-specific sounding reference signals (SRSs) when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone, wherein the one or more zone-specific SRSs are associated with a first uplink timing advance (TA); and transmit one or more physical layer uplink channels when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0014] Other objects and advantages associated with aspects disclosed herein will be apparent to those skilled in the art based on the accompanying drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0015] The accompanying drawings are presented to aid in the description of various aspects of the disclosure and are provided solely for illustration of various aspects.

[0016] Figure 1 An example wireless communication system in accordance with aspects of the present disclosure is illustrated.

[0017] Figure 2A , Figure 2B and Figure 2C An example wireless network structure in accordance with aspects of the present disclosure is illustrated.

[0018] Figure 3A , Figure 3B and Figure 3C are simplified block diagrams of several example aspects of components that can be employed in a user equipment (UE), a base station, and a network entity, respectively, and configured to support communications as taught herein.

[0019] Figure 4 Different radio resource control (RRC) states available in new radio (NR) in accordance with aspects of the present disclosure are illustrated.

[0020] Figure 5 Examples of various positioning methods supported in new radio (NR) in accordance with aspects of the present disclosure are illustrated.

[0021] Figure 6 is a diagram illustrating an example frame structure in accordance with aspects of the present disclosure.

[0022] Figure 7A and Figure 7BAn example postpone mobile terminated location request (MT LR) procedure for downlink and uplink based positioning methods according to aspects of the present disclosure is illustrated.

[0023] Figure 8 An example radio resource control (RRC) “SRS-PosRRC-Inactive” IE according to aspects of the present disclosure is illustrated.

[0024] Figure 9A And Figure 9B An example postpone MT LR procedure for downlink and uplink based positioning methods with positioning SRS pre-configuration according to aspects of the present disclosure is illustrated.

[0025] Figure 10 is a diagram illustrating example UE mobility scenarios through multiple zones according to aspects of the present disclosure.

[0026] Figure 11 is a diagram illustrating preconfigured positioning sounding reference signal (SRS) structures according to aspects of the present disclosure.

[0027] Figure 12 And Figure 13 An example method of wireless communication according to aspects of the present disclosure is illustrated. DETAILED DESCRIPTION

[0028] Aspects of the present disclosure are provided in the following description and related drawings directed to various examples provided for illustrative purposes. Alternative aspects can be devised without departing from the scope of the present disclosure. Additionally, well-known elements of the present disclosure will not be described or will be omitted so as not to obscure the relevant details of the examples.

[0029] Various aspects generally relate to uplink sounding reference signal (SRS) transmissions for positioning. Some aspects more specifically relate to determining a timing advance (TA) for transmitting uplink SRSs in SRS validity areas. In some examples, a user equipment (UE) receives one or more SRS configurations associated with one or more SRS validity areas, each SRS validity area of the one or more SRS validity areas including one or more cells. While operating in a radio resource control (RRC) inactive state and while camped on a first cell of a first SRS validity area of the one or more SRS validity areas, the UE transmits one or more first area-specific SRSs based on the one or more SRS configurations, a downlink reference timing, and a first value of an uplink TA of the UE. In an aspect, the first value of the uplink TA is determined based on one of a plurality of uplink TA derivation rules, where the plurality of uplink TA derivation rules includes: (1) a first uplink TA derivation rule including obtaining a value of the uplink TA from a latest serving cell within a SRS validity area associated with the UE; (2) a second uplink TA derivation rule including permitting the UE to autonomously adjust a value of the uplink TA; and (3) a third uplink TA derivation rule including obtaining the value of the uplink TA from a cell on which the UE is camped. In an aspect, the one of the plurality of uplink TA derivation rules: (1) applies to all cells in a first sub-area of a plurality of sub-areas of the first SRS validity area that contains the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-area-specific SRS transmission, or both; or (4) is determined based on whether a change in the downlink reference timing has exceeded a threshold.

[0030] In some examples, while operating in an RRC inactive state and while camped on a first cell of a first SRS validity area, a UE can transmit one or more area-specific SRSs, where the one or more area-specific SRSs are associated with a first uplink TA. While operating in the RRC inactive state and while camped on the first cell of the first SRS validity area, the UE can also transmit one or more physical layer uplink channels, where the one or more physical layer uplink channels are associated with a second uplink TA.

[0031] Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. In some examples, by determining an appropriate uplink TA value for the zone-specific SRS, the described techniques can be used to reduce interference of the zone-specific SRS to other uplink channels.

[0032] The words “exemplary” and / or “example” are used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” and / or “example” is not necessarily to be construed as preferred or advantageous over other aspects. Likewise, the term “aspects of the disclosure” does not require that all aspects of the disclosure include the discussed feature, advantage or mode of operation.

[0033] Those skilled in the art will appreciate that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that can be referenced throughout the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof, depending in part on the particular applications, embodiments, and / or technologies involved. Further, some of the embodiments described herein can be implemented in software and / or firmware, which can be stored in any non-transitory computer-readable medium.

[0034] Further, many aspects are described in terms of sequences of actions to be performed by, for example, elements of a computing device. It will be recognized that various actions described herein can be performed by specific circuits (e.g., application specific integrated circuits (ASICs)), by program instructions being executed by one or more processors, or by a combination of both. Additionally, the sequence(s) of actions described herein can be considered to be embodied entirely within any form of non-transitory computer-readable storage medium having stored therein a corresponding set of computer instructions that, upon execution, would cause or instruct an associated processor of a device to perform the functionality described herein. Thus, the various aspects of the disclosure can be embodied in a number of different forms, all of which have been contemplated to be within the scope of the claimed subject matter. In addition, for each of the aspects described herein, the corresponding form of the aspect can be described herein as, for example, “logic configured to” perform the described action.

[0035] As used herein, the terms “user equipment” (UE) and “base station” are not intended to be specific or otherwise limited to any particular radio access technology (RAT), unless otherwise indicated. In general, a UE can be any wireless communication device (e.g., a mobile phone, router, tablet computer, laptop computer, consumer asset-positioning device, wearable device (e.g., smartwatch, glasses, augmented reality (AR) / virtual reality (VR) headset, etc.), vehicle (e.g., automobile, motorcycle, bicycle, etc.), Internet of Things (IoT) device, etc.) used by a user to communicate over a wireless communication network. A UE can be mobile or can (e.g., at certain times) be stationary, and can communicate with a radio access network (RAN). As used herein, the term “UE” can be referred to interchangeably as an “access terminal” or “AT,” a “client device,” a “wireless device,” a “subscriber device,” a “subscriber terminal,” a “subscriber station,” a “user terminal,” or “UT,” a “mobile device,” a “mobile terminal,” a “mobile station,” or variations thereof. Generally, UEs can communicate with one another directly (e.g., using a direct wireless connection implemented according to one or more wireless communication standards) or indirectly (e.g., via a network access device such as a base station). Of course, UEs can also communicate with other types of devices (e.g., via a network access device and / or network) including, but not limited to, core network devices (e.g., location server), Internet servers, other devices via the Internet, and / or other devices via a private network.

[0036] A base station can operate according to one of a number of RATs to communicate with UEs depending on the network in which it is deployed, and can be alternatively referred to as an access point (AP), a network node, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), a new radio (NR) NodeB (also referred to as a gNB or gNodeB), etc. Base stations can be used to support wireless access by UEs, including supporting data, voice, and / or signaling connections for the UEs depending on the capabilities of the base stations and the needs of the UEs. In some systems, base stations can provide only edge node signaling functions, while in other systems, they can provide additional control and / or network management functions. A communication link through which UEs can send signals to a base station is called an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). A communication link through which the base station can send signals to UEs is called a downlink (DL) or forward link channel (e.g., a paging channel, a control channel, a broadcast channel, a forward traffic channel, etc.). As used herein, the term “traffic channel” (TCH) can refer to an uplink / reverse or downlink / forward traffic channel.

[0037] The term “base station” can refer to a single physical transmission-reception point (TRP) or multiple physical TRPs that can or can not be co-located. For example, where the term “base station” refers to a single physical TRP, the physical TRP can be an antenna of the base station corresponding to a cell (or cell sector) of the base station. Where the term “base station” refers to multiple co-located physical TRPs, the physical TRPs can be an array of antennas of the base station (e.g., as in a multiple-input multiple-output (MIMO) system or where the base station employs beamforming). Where the term “base station” refers to multiple non-co-located physical TRPs, the physical TRPs can be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transmission medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, the non-co-located physical TRPs can be the serving base station receiving the measurement report from the UE and a neighbor base station whose reference radio frequency (RF) signal the UE is measuring. Because, as used herein, a TRP is a point from or to which the base station sends and receives wireless signals, references to transmissions from or receptions at a base station should be understood to refer to particular TRPs of the base station.

[0038] In some implementations that support positioning of UEs, a base station can not support wireless access by a UE (e.g., can not support data, voice, and / or signaling connections for the UE), but can instead transmit reference signals to the UE to be measured by the UE and / or can receive and measure signals transmitted by the UE. Such a base station can be referred to as a positioning beacon (e.g., where it transmits signals to the UE) and / or as a location measurement unit (e.g., where it receives and measures signals from the UE).

[0039] An “RF signal” comprises an electromagnetic wave of a given frequency that transports information through the space between a transmitter and a receiver. As used herein, a transmitter can transmit a single “RF signal” or multiple “RF signals” to a receiver. However, due to the propagation characteristics of RF signals over multipath channels, the receiver can receive multiple “RF signals” corresponding to each transmitted RF signal. The same transmitted RF signal on different paths between the transmitter and receiver can be referred to as a “multipath” RF signal. As used herein, where the term “signal” clearly refers to a wireless signal or an RF signal according to the context, an RF signal can also be referred to as a “wireless signal” or simply a “signal.”

[0040] Figure 1An example wireless communications system 100 in accordance with aspects of the present disclosure is illustrated. The wireless communications system 100, which can also be referred to as a wireless wide area network (WW AN), can include various base stations 102, labeled “BS” and various UEs 104. The base stations 102 can include macro cell base stations (high power cellular base stations) and / or small cell base stations (low power cellular base stations). In an aspect, the macro cell base station can include eNBs and / or ng-eNBs (where the wireless communications system 100 corresponds to an LTE network), or gNBs (where the wireless communications system 100 corresponds to an NR network), or a combination of both, and the small cell base stations can include femtocells, pico cells, micro cells, and the like.

[0041] The base stations 102 can collectively form a RAN and interface with a core network 170 (e.g., an evolved packet core (EPC), or a 5G core (5GC)) through backhaul links 122 (e.g., SI, X2, Xn, etc. interfaces), and with one or more location servers 172 (e.g., location management function (LMF) or secure user plane location (SUPL) location platform (SLP)) through the core network 170. The location server 172 can be part of the core network 170 or can be external to the core network 170. The location server 172 can be integrated with the base stations 102. The UEs 104 can communicate directly with the location server 172, either directly or indirectly via the base stations 102. For example, the UEs 104 can communicate with the location server 172 via a base station 102 that is currently serving the UE 104. The UEs 104 can also communicate with the location server 172 through another path, such as via an application server (not shown), via another network, such as via a wireless local area network (WLAN) access point (AP) (e.g., the AP 150 described below), etc. The communication between the UEs 104 and the location server 172 can be represented as an indirect connection (e.g., through the core network 170, etc.) or a direct connection (e.g., as shown via the direct connection 128) for signaling purposes, with intermediate nodes (if any) omitted from the signaling diagrams for the sake of clarity.

[0042] The base stations 102 can perform functions such as, but not limited to, orchestrating the delivery of user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations 102 can communicate with one another directly or indirectly (e.g., through the EPC / 5GC) over backhaul links 134, which can be wired or wireless.

[0043] The base stations 102 can wirelessly communicate with the UEs 104. Each of the base stations 102 can provide communication coverage for a respective geographic coverage area 110. In an aspect, one or more of the cells can be supported by the base station 102 in each of the geographic coverage areas 110. A “cell” is a logical communication entity used for communication to UEs (e.g., through some frequency resource, which can be referred to as a carrier frequency, a component carrier, a carrier, or a frequency band, etc.) and can be associated with an identifier (e.g., a physical cell identifier (PCI), an enhanced cell identifier (ECI), a virtual cell identifier (VCI), a cell global identifier (CGI), etc.) used to distinguish the cell from other cells operating on the same or different carrier frequencies within the same or different geographic coverage areas 110. In some cases, different cells can be configured according to different protocol types (e.g., machine type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or other protocol types) that can provide access for different types of UEs. Because a cell is supported by a particular base station, the term “cell” can refer to either or both of a logical communication entity and a base station supporting the logical communication entity, depending on context. In addition, since a TRP is typically a physical transmission point of a cell, the terms “cell” and “TRP” can be used interchangeably. In some cases, the term “cell” can also refer to a geographic coverage area of a base station (e.g., a sector) as well, as long as a carrier frequency can be detected and used for communication within the geographic coverage area 110.

[0044] While the geographic coverage areas 110 of the neighboring macro cell base stations 102 can partially overlap (e.g., in the handover region), some of the geographic coverage areas 110 can substantially overlap with larger geographic coverage areas 110. For example, small cell base stations 102' (labeled “SC” for “small cell”) can have a geographic coverage area 110' that substantially overlaps with one or more of the geographic coverage areas 110 of the macro cell base stations 102. A network that includes both small cell and macro cell base stations can be known as a heterogeneous network. A heterogeneous network can also include Home eNBs (HeNBs), where an HeNB can provide service to a restricted group known as a closed subscriber group (CSG).

[0045] The communication links 120 between the base stations 102 and the UEs 104 can include uplink (also referred to as reverse link) transmissions from a UE 104 to a base station 102 and / or downlink (DL) (also referred to as forward link) transmissions from a base station 102 to a UE 104. The communication links 120 can use MIMO antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication links 120 can be through one or more carrier frequencies. Allocation of carriers can be asymmetric with respect to downlink and uplink (e.g., more or less carriers can be allocated for downlink than for uplink).

[0046] Wireless communications system 100 can also include a WLAN access point (AP) 150 in communication with WLAN stations (STAs) 152 via communication links 154 in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in an unlicensed frequency spectrum, the WLAN STAs 152 and / or the WLAN AP 150 can perform clear channel assessment (CCA) or listen before talk (LBT) procedures to ensure the channel is available prior to communicating.

[0047] The small cell base stations 102' can operate in a licensed and / or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell base stations 102' can employ LTE or NR technology and use the same 5 GHz unlicensed frequency spectrum as used by the WLAN AP 150. The small cell base stations 102' employing LTE / 5G in an unlicensed frequency spectrum can boost coverage of the access network and / or increase capacity of the access network. NR in an unlicensed frequency spectrum can be referred to as NR-U. LTE in an unlicensed frequency spectrum can be referred to as LTE-U, License Assisted Access (LAA), or MulteFire ® .

[0048] The wireless communications system 100 can also include millimeter wave (mmW) base stations 180 that can operate in mmW frequencies and / or near mmW frequencies in communication with UEs 182. Extremely high frequency (EHF) is the part of the radio frequency spectrum between 30 GHz and 300 GHz. EHF has a wavelength of 1 millimeter to 10 millimeters. Radio waves in this band can be referred to as a millimeter wave. Near mmW can extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, which is also referred to as centimeter wave. Communications using the mmW / near mmW radio frequency band have high path loss and a relatively short range. The mmW base stations 180 and the UEs 182 can utilize beamforming (transmit and / or receive) over mmW communication links 184 to compensate for the extremely high path loss and short range. Further, it should be appreciated that in alternative configurations, one or more base stations 102 can also transmit using mmW or near mmW and beamforming. Thus, it should be appreciated that the foregoing merely illustrates example configurations and should not be construed as limiting various aspects disclosed herein.

[0049] Transmit beamforming is a technique for focusing the RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts a signal, it broadcasts the signal in all directions (omni-directionally). With transmit beamforming, the network node determines where a given target device (e.g., a UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster and stronger RF signal (in terms of data rate) for the receiving device. To change the direction of the RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters in the broadcast. For example, the network node can use an array of antennas (referred to as a “phased array” or “antenna array”), which in effect moves the beam without actually moving the antennas. Specifically, the RF current from the transmitter is fed to the individual antennas with the correct phase relationship so that the radio waves from the separate antennas add together to increase the radiation in a desired direction, while cancelling to suppress radiation in undesired directions.

[0050] The transmit beams can be quasi co-located, meaning that they appear to have the same parameters to a receiver (e.g., a UE), regardless of whether the network node’s own transmit antennas are physically co-located. In NR, there are four types of quasi co-location (QCL) relationships. Specifically, a given type of QCL relationship means that certain parameters about a second reference RF signal on a second beam can be derived from information about a source reference RF signal on a source beam. Thus, if the source reference RF signal is QCL Type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, average delay, and delay spread of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type C, the receiver can use the source reference RF signal to estimate the Doppler shift and average delay of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type D, the receiver can use the source reference RF signal to estimate the spatial receive parameters of a second reference RF signal transmitted on the same channel.

[0051] In receive beamforming, the receiver uses a receive beam to amplify an RF signal detected on a given channel. For example, the receiver can increase a gain setting and / or adjust a phase setting of an antenna array in a particular direction to amplify (e.g., increase a gain level of) an RF signal received from that direction. Thus, when a receiver is said to beamform in a certain direction, this means that the beam gain in that direction is high relative to the beam gain along other directions, or that the beam gain in that direction is the highest compared to the beam gains of all other receive beams available to the receiver in that direction. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal to interference plus noise ratio (SINR), etc.) of the RF signal received from that direction.

[0052] The transmit beams and receive beams can be spatially related. Spatial relation means that parameters for a second beam (e.g., a transmit beam or a receive beam) for a second reference signal can be derived from information about a first beam (e.g., a receive beam or a transmit beam) for a first reference signal. For example, a UE can use a particular receive beam to receive a reference downlink reference signal (e.g., a synchronization signal block (SSB)) from a base station. The UE can then form a transmit beam for transmitting an uplink reference signal (e.g., a sounding reference signal (SRS)) to that base station based on parameters of the receive beam.

[0053] Note that depending on the entity forming the “downlink” beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming a downlink beam to transmit a reference signal to a UE, the downlink beam is a transmit beam. However, if the UE is forming a downlink beam, the downlink beam is a receive beam to receive the downlink reference signal. Similarly, depending on the entity forming the “uplink” beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming an uplink beam, the uplink beam is an uplink receive beam, while if the UE is forming an uplink beam, the uplink beam is an uplink transmit beam.

[0054] The electromagnetic spectrum is often subdivided based on frequency / wavelength into various classes, bands, channels, and so forth. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz to 7. 125 GHz) and FR2 (24.25 GHz to 52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as a “Sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often (interchangeably) referred to as a “millimeter wave” band in documents and articles, despite being different from the “millimeter wave” frequencies designated by the INTERNATIONAL TELECOMMUNICATION UNION (ITU) as 27-300 GHz. Regardless of the nomenclature, this band of frequencies is commonly referred to in the industry as a “millimeter wave” band because the wavelengths range from 1-10 millimeters— compared to Sub-6 GHz wavelengths that range from 300 mm to 1 mm. ® The extremely high frequency (EHF) band (30 GHz to 300 GHz) has been identified as a “millimeter wave” band by the INTERNATIONAL TELECOMMUNICATION UNION (ITU).

[0055] The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7. 125 GHz to 24.25 GHz). Bands falling within FR3 can inherit FR1 and / or FR2 characteristics, and thus can effectively extend the characteristics of FR1 and / or FR2 to mid-band frequencies. Moreover, even higher bands are currently under exploration to extend 5G NR operation beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6 GHz to 71 GHz), FR4 (52.6 GHz to 114.25 GHz), and FR5 (114.25 GHz to 300 GHz). Each of these higher bands falls within the EHF band of frequencies.

[0056] With the above aspects in mind, unless specifically stated otherwise, it should be understood that if the term “sub-6 GHz” or the like is used herein, it can be broadly interpreted to denote frequencies that can be less than 6 GHz, can be within FR1, or can include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that if the term “millimeter wave” or the like is used herein, it can be broadly interpreted to denote frequencies that can include mid-band frequencies, can be within FR2, FR4, FR4-a, or FR4-1, and / or FR5, or can be within the EHF frequency band.

[0057] In a multi-carrier system, such as 5G, one of the carrier frequencies is referred to as the “primary carrier” or “anchor carrier” or “primary serving cell” or “PCell” and the remaining carrier frequencies are referred to as “secondary carriers” or “secondary serving cells” or “SCells.” In carrier aggregation, the anchor carrier is the carrier operating on the primary frequency (e.g., FR1) used by the UE 104 / 182 and the cell in which the UE 104 / 182 performs an initial radio resource control (RRC) connection establishment procedure or initiates a RRC connection reestablishment procedure. The primary carrier carries all common and UE-specific control channels and can be a carrier in a licensed frequency (although this is not always the case). The secondary carrier is a carrier operating on a second frequency (e.g., FR2) that can be configured and can be used to provide additional radio resources once an RRC connection is established between the UE 104 and the anchor carrier. In some cases, the secondary carrier can be a carrier in an unlicensed frequency. The secondary carrier can contain only necessary signaling information and signals, e.g., those that are UE-specific can not be present in the secondary carrier since both the primary uplink and primary downlink carriers are typically UE-specific. This means that different UEs 104 / 182 in a cell can have different downlink primary carriers. The same is true for the uplink primary carrier. The network is able to change the primary carrier for any UE 104 / 182 at any time. This is done, for example, to balance the load on different carriers. Since a “serving cell” (whether a PCell or an SCell) corresponds to a carrier frequency / component carrier through which a certain base station communicates, the terms “cell,” “serving cell,” “component carrier,” “carrier frequency,” etc. can be used interchangeably.

[0058] For example, still referring to Figure 1One of the frequencies used by the macrocell base station 102 can be an anchor carrier (or "PCell"), and other frequencies used by the macrocell base station 102 and / or mmW base station 180 can be secondary carriers ("SCells"). Simultaneous transmission and / or reception of multiple carriers enables the UE 104 / 182 to significantly increase its data transmission and / or reception rate. For example, two 20 MHz aggregated carriers in a multi-carrier system would theoretically result in doubling the data rate as compared to a single 20 MHz carrier (i.e., 40 MHz).

[0059] The wireless communications system 100 can also include a UE 164 that can communicate with macro cell base station 102 over a communication link 120 and / or with mmW base station 180 over a mmW communication link 184. For example, the macro cell base station 102 can support a PCell and one or more SCells for the UE 164, and the mmW base station 180 can support one or more SCells for the UE 164.

[0060] In some cases, the UEs 164 and 182 can be capable of sidelink communication. Sidelink-capable UEs (SL-UEs) can communicate with base station 102 using a Uu interface (i.e., the air interface between a UE and a base station) over communication link 120. SL-UEs (e.g., UEs 164, 182) can also directly communicate with each other using a PC5 interface (i.e., the air interface between sidelink-capable UEs) over wireless sidelink 160. Wireless sidelink (or simply "sidelink") is an adaptation of the core cellular network (e.g., LTE, NR) standard that allows for direct communication between two or more UEs without communicating through a base station. Sidelink communication can be unicast or multicast, and can be used for device-to-device (D2D) media sharing, vehicle-to-vehicle (V2V) communications, vehicle-to-everything (V2X) communications (e.g., cellular V2X (cV2X) communications, enhanced V2X (eV2X) communications, etc.), emergency rescue applications, etc. One or more of the SL-UEs in a group of SL-UEs utilizing sidelink communication can be within the geographic coverage area 110 of a base station 102. Other SL-UEs in such a group can be outside the geographic coverage area 110 of a base station 102, or be unable to receive transmissions from base stations 102 for other reasons. In some cases, groups of SL-UEs communicating via sidelink communication can utilize a one-to-many (1 :M) system, where each SL-UE transmits to every other SL-UE in the group. In some cases, the base station 102 facilitates scheduling of resources for sidelink communications. In other cases, sidelink communications are performed between SL-UEs without the involvement of base station 102.

[0061] In an aspect, the sidelink 160 can operate over a wireless communication medium of interest that can be shared with other wireless communications between other vehicles and / or infrastructure access points and other RATs. A "medium" can include one or more time, frequency, and / or space communication resources (e.g., encompassing one or more channels across one or more carriers) associated with wireless communications between one or more transmitter / receiver pairs. In an aspect, the medium of interest can correspond to at least a portion of an unlicensed frequency band that is shared between various RATs. Although different licensed frequency bands have been reserved for certain communication systems (e.g., by government entities such as the Federal Communications Commission (FCC) of the United States), these systems, particularly those employing small cell access points, have recently extended operations into unlicensed frequency bands such as the Unlicensed National Information Infrastructure (U-NII) band used by Wireless Local Area Network (WLAN) technologies, most notably the IEEE 802.1 lx WLAN technologies commonly referred to as "Wi-Fi." Example systems of this type include different variations of CDMA systems, TDMA systems, FDMA systems, Orthogonal FDMA (OFDMA) systems, Single-Carrier FDMA (SC-FDMA) systems, etc.

[0062] Note that although Figure 1 Only two of these UEs are illustrated as SL-UEs (i.e., UE 164 and UE 182), but any of the illustrated UEs can be SL-UEs. Further, although only UE 182 is described as being capable of beamforming, any of the illustrated UEs, including UE 164, can be capable of beamforming. Where the SL-UEs are capable of beamforming, they can beamform toward one another (i.e., toward other SL-UEs), toward other UEs (e.g., UE 104), toward base stations (e.g., base station 102, base station 180, small cell 102', access point 150), etc. Thus, in some cases, UE 164 and UE 182 can utilize beamforming over sidelink 160.

[0063] In Figure 1 example, the illustrated UEs (for simplicity, only UE 164 and UE 182 are Figure 1Any of the UEs 104 (shown as a single UE 104) can receive signals 124 from one or more Earth orbiting space vehicles (SVs) 112, such as satellites. In an aspect, the SVs 112 can be part of a satellite positioning system of which the UEs 104 can use as an independent source of location information. A satellite positioning system typically includes a system of transmitters (e.g., SVs 112) positioned in orbit about the Earth that transmit signals (e.g., signals 124) that a receiver (e.g., a UE 104) can use to determine its location on or above the Earth based, at least in part, on known positions of the transmitters and the times of arrival of the signals from the transmitters. Such transmitters typically transmit signals marked with a repeating pseudo-random noise (PN) code of a set number of chips. While typically located in SVs 112, transmitters can sometimes be located on ground-based control stations, base stations 102, and / or other UEs 104. The UEs 104 can include one or more specialized receivers designed specifically for use in receiving signals 124 for the purpose of deriving geographic location information from the SVs 112.

[0064] In a satellite positioning system, the use of signals 124 can be augmented by various satellite-based augmentation systems (SBAS) that can be associated with one or more global and / or regional navigation satellite systems or that can otherwise enable the use of one or more global and / or regional navigation satellite systems. For example, an SBAS can include an augmentation system(s) that provides integrity information, differential corrections, etc. to one or more global and / or regional navigation satellite systems, such as the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multi

[0065] In an aspect, the SVs 112 additionally or alternatively can be part of one or more non-terrestrial networks (NTNs). In an NTN, the SVs 112 connect to an Earth station (also referred to as a ground station, NTN gateway, or gateway), which in turn connects to elements in the 5G network, such as a modified base station 102 (without a terrestrial antenna) or a network node in the 5GC. This element in turn will provide access to other elements in the 5G network and ultimately to entities outside the 5G network, such as Internet web servers and other user equipment. In this way, the UEs 104 can receive communication signals (e.g., signals 124) from the SVs 112 in lieu of or in addition to communication signals from terrestrial base stations 102.

[0066] The wireless communications system 100 can also include one or more UEs, such as UE 190, that connects indirectly to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links (referred to as “sidelinks”). In Figure 1 In an example, the UE 190 has a D2D P2P link 192 with one of the UEs 104 connected to one of the base stations 102 (e.g., with which it can indirectly obtain cellular connectivity), and a D2D P2P link 194 with WLAN STA 152 connected to the WLAN AP 150 (with which it can indirectly obtain WLAN-based Internet connectivity). In an example, the D2D P2P links 192 and 194 can be supported with any well-known D2D RAT (such as LTE Direct (LTE-D), WI-FI DIRECT (Wi-Fi), BLUETOOTH®, Bluetooth ® , Bluetooth ® , etc.).

[0067] Figure 2A An example wireless network structure 200 is illustrated. For example, a 5GC 210 (also referred to as a Next Generation Core (NGC)) can be functionally

[0068] Another optional aspect can include a location server 230 that can communicate with the 5GC 210 to provide location assistance for UEs 204. The location server 230 can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternately can each correspond to a single server. The location server 230 can be configured to support one or more location services for UEs 204 that can connect to the location server 230 via the core network, the 5GC 210, and / or via the Internet (not illustrated). Further, the location server 230 can be integrated into a component of the core network, or alternately can be external to the core network (e.g., a third party server, such as an original equipment manufacturer (OEM) server or a service server).

[0069] Figure 2B Another example wireless network structure 240 is illustrated. A 5GC 260 (which can correspond to the 5GC 210) is shown that includes an AMF 262, a UDM 264, and a location management function (LMF) 266. The AMF 262 can communicate with a base station 220 (which can correspond to the base stations 220a, 220b, 220c) over an N2 interface 268. The base station 220 can also communicate with a UE 204 over an Uu interface 270. The AMF 262 can also communicate with the UDM 264 over an N8 interface 272. The AMF 262 can also communicate with the LMF 266 over an N3gpp interface 274. Figure 2AThe 5GC210 in the document can be functionally considered as a control plane function provided by the Access and Mobility Management Function (AMF) 264 and a user plane function provided by the User Plane Function (UPF) 262, which work together to form the core network (i.e., 5GC 260). The functions of AMF264 include: registration management, connection management, reachability management, mobility management, lawful interception, transmission of session management (SM) messages between one or more UEs 204 (e.g., any of the UEs described herein) and the Session Management Function (SMF) 266, transparent proxy service for routing SM messages, access authentication and access authorization, transmission of short message service (SMS) messages between UE 204 and the Short Message Service Function (SMSF) (not shown), and Security Anchoring Functionality (SEAF). AMF264 also interacts with the Authentication Server Function (AUSF) (not shown) and UE 204, and receives an intermediate key established as a result of the UE 204's authentication process. In the case of UMTS (Universal Mobile Telecommunications System) Subscriber Identity Module (USIM) authentication, AMF 264 retrieves security material from the AMF. AMF 264 also includes Security Context Management (SCM). The SCM receives a key from the SEAF and uses this key to derive an access network-specific key. AMF 264 functionality also includes location service management for regulatory services, transmission of location service messages between UE 204 and Location Management Function (LMF) 270 (which acts as location server 230), transmission of location service messages between NG-RAN 220 and LMF 270, Evolved Packet System (EPS) bearer identifier allocation for EPS interoperability, and UE 204 mobility event notification. Furthermore, AMF 264 also supports non-3GPP... ® (Third Generation Partner Program) Access network functionality.

[0070] Functions of the UPF 262 include acting as an anchor point (when applicable) for intra- / inter-RAT mobility, acting as a external protocol data unit (PDU) session point of interconnect to a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) handling for user plane (e.g., uplink / downlink rate enforcement, reflective QoS marking in the downlink), uplink traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in the uplink and downlink, downlink packet buffering and downlink data notification triggering, and transmitting and forwarding of one or more “end markers.” The UPF 262 can also support transfer of location services messages between the UE 204 and a location server, such as the SLP 272, over the user plane.

[0071] Functions of the SMF 266 include session management, UE Internet protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering at the UPF 262 for proper

[0072] Another optional aspect can include an LMF 270, which can be in communication with the 5GC 260 to provide location assistance for UEs 204. The LMF 270 can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternately can each correspond to a single server. The LMF 270 can be configured to support one or more location services for UEs 204, which can connect to the LMF 270 via the core network, 5GC 260, and / or via the Internet (not illustrated). The SLP 272 can support similar functions as the LMF 270, but whereas the LMF 270 can communicate with the AMF 264, NG-RAN 220, and UEs 204 over the control plane (e.g., using interfaces and protocols intended to carry signaling messages, rather than voice or data), the SLP 272 can communicate with UEs 204 and external clients (e.g., third-party servers 274) over the user plane (e.g., using protocols intended to carry voice and / or data, such as transmission control protocol (TCP) and / or IP).

[0073] Yet another optional aspect can include a third party server 274 that can communicate with the LMF 270, the SLP 272, the 5GC 260 (e.g., via the AMF 264 and / or the UPF 262), the NG-RAN 220, and / or the UE 204 to obtain location information (e.g., a location estimate) for the UE 204. Thus, in some cases, the third party server 274 can be referred to as a Location Services (LCS) client or an external client. The third party server 274 can be implemented as a number of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternatively can each correspond to a single server.

[0074] The user plane interface 263 and control plane interface 265 connect the 5GC 260, and in particular the UPF 262 and AMF 264, respectively, to one or more gNBs 222 and / or ng-eNBs 224 in the NG-RAN 220. The interface between gNBs 222 and / or ng-eNBs 224 and AMF 264 is referred to as the “N2” interface, while the interface between gNBs 222 and / or ng-eNBs 224 and UPF 262 is referred to as the “N3” interface. The gNBs 222 and / or ng-eNBs 224 of the NG-RAN 220 can communicate with one another directly via a backhaul connection 223 referred to as an “Xn-C” interface. One or more of the gNBs 222 and / or ng-eNBs 224 can communicate with one or more UEs 204 over a wireless interface referred to as the “Uu” interface.

[0075] The functionality of a gNB 222 can be divided between a gNB central unit (gNB-CU) 226, one or more gNB distributed units (gNB-DUs) 228, and one or more gNB radio units (gNB-RUs) 229. The gNB-CU 226 is a logical node that includes base station functionality other than that specifically allocated to the gNB-DUs 228, including transfer of user data, mobility control, radio access network sharing, positioning, session management, etc. More specifically, the gNB-CU 226 typically hosts the radio resource control (RRC), service data adaptation protocol (SDAP), and packet data convergence protocol (PDCP) protocols of the gNB 222. The gNB-DU 228 is a logical node that typically hosts the radio link control (RLC) and medium access control (MAC) layers of the gNB 222. Its operation is controlled by the gNB-CU 226. One gNB-DU 228 can support one or more cells, and one cell is supported by only one gNB-DU 228. The interface 232 between the gNB-CU 226 and the one or more gNB-DUs 228 is referred to as the “Fl” interface. The physical (PHY) layer functionality of the gNB 222 is typically hosted by one or more standalone gNB-RUs 229 that perform functions such as power amplification and signal transmission / reception. The interface between the gNB-DU 228 and the gNB-RU 229 is referred to as the “Fx” interface. Thus, the UE 204 communicates with the gNB-CU 226 via the RRC layer, the SDAP layer, and the PDCP layer, with the gNB-DU 228 via the RLC layer and the MAC layer, and with the gNB-RU 229 via the PHY layer.

[0076] Deployments of communication systems, such as 5G NR systems, can be arranged in a variety of ways with various components or constituent parts. In a 5G NR system or network, a network node, network entity, mobility element of a network, RAN node, core network node, network element, or network equipment, such as a base station or one or more elements (or one or more components) performing base station functionality, can be implemented in an aggregated or disaggregated architecture. For example, a base station, such as a Node B (NB), an evolved NB (eNB), an NR base station, a 5G NB, an access point (AP), a transmission reception point (TRP), or a cell, etc., can be implemented as an aggregated base station (also referred to as a standalone base station or a monolithic base station) or a disaggregated base station.

[0077] A disaggregated base station can be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A disaggregated base station can be configured to utilize a protocol stack that is physically or logically distributed between two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs). In some aspects, a CU can be implemented within a RAN node, and one or more DUs can be co-located with the CU, or alternatively, can be geographically or virtually distributed in one or more other RAN nodes. The DUs can be implemented to be in communication with one or more RUs. Each of the CU, DU, and RU can also be implemented as virtual units, i.e., a virtual central unit (VCU), virtual distributed unit (VDU), or virtual radio unit (VRU).

[0078] Base station type operations or network designs can take into account the disaggregated nature of base station functionality. For example, a disaggregated base station can be utilized in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (such as the network configuration by the O-RAN ALLIANCE ® Disaggregation can include distributing functionality across two or more units at various physical locations, as well as virtually distributing functionality of at least one unit, which can enable flexibility in network design. The various units of a disaggregated base station or disaggregated RAN architecture can be configured for wired or wireless communication with at least one other unit.

[0079] Figure 2C An example disaggregated base station architecture 250 is illustrated in accordance with aspects of the present disclosure. The disaggregated base station architecture 250 can include one or more central units (CUs) 280 (e.g., gNB-CUs 226) that can communicate with a core network 267 (e.g., 5GC 210, 5GC 260) directly via a backhaul link, or indirectly through one or more disaggregated base station units, such as a near real-time (near-RT) RAN intelligent controller (RIC) 259 via an E2 link or a non-RT RIC 257 associated with a service management and orchestration (SMO) framework 255, or both. The CUs 280 can be in communication with one or more DUs 285 (e.g., gNB-DUs 228) via respective fronthaul links, such as an Fl interface. The DUs 285 can be in communication with one or more radio units (RUs) 287 (e.g., gNB-RUs 229) via respective front-haul links. The RUs 287 can be in communication with respective UEs 204 via one or more radio frequency (RF) access links. In some implementations, a UE 204 can be simultaneously served by multiple RUs 287.

[0080] Each of these units (i.e., CU 280, DU 285, RU 287, and near-RT RIC 259, non-RT RIC 257, and SMO framework 255) can include or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via wired or wireless transmission mediums. The associated processor or controller providing instructions to the communication interfaces of each of these units or to these units can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or transmit signals to one or more of the other units over a wired transmission medium. Additionally, the units can include a wireless interface that can include a receiver, a transmitter, or a transceiver (such as a RF transceiver) configured to receive or transmit signals, or both, to one or more of the other units over a wireless transmission medium.

[0081] In some aspects, CU 280 can host one or more higher layer control functions. Such control functions can include RRC, PDCP, or service data adaptation protocol (SDAP), among others. Each control function can utilize an interface configured to communicate signals with other control functions hosted by CU 280. CU 280 can be configured to handle user plane functionality (i.e., central unit-user plane (CU-UP)), control plane functionality (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some implementations, CU 280 can be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP units can communicate bi-directionally with the CU-CP units via an interface, such as an El interface. CU 280 can be implemented to communicate with DU 285 as needed for network control and signaling.

[0082] DU 285 can correspond to a logical unit that includes one or more base station functions for controlling operation of one or more RUs 287. In some aspects, DU 285 can be at least partially in accordance with a functional split, such as a functional split by the third generation partnership project (3GPP ®to host one or more of the RLC layer, the MAC layer, and one or more high-PHY layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, etc.). In some aspects, the DU 285 can also host one or more low-PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 285 or with control functions hosted by the CU 280.

[0083] Lower layer functionality can be implemented by one or more RUs 287. In some deployments, an RU 287 controlled by a DU 285 can correspond to a logical node that hosts RF processing functions or low-PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, or physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on a functional split, such as a lower layer functional split. In such an architecture, an RU 287 can be implemented to handle over-the-air (OTA) communications with one or more UEs 204. In some implementations, real-time and non-real-time aspects of control plane and user plane communications with an RU 287 can be controlled by a corresponding DU 285. In some scenarios, this configuration can enable implementation of DUs 285 and CUs 280 in a cloud-based RAN architecture, such as a vRAN architecture.

[0084] The SMO framework 255 can be configured to support RAN deployment and orchestration of non-virtualized network elements and virtualized network elements. For non- virtualized network elements, the SMO framework 255 can be configured to support deployment of dedicated physical resources for RAN coverage requirements, which can be managed via an operations and maintenance interface, such as an Ol interface. For virtualized network elements, the SMO framework 255 can be configured to interact with a cloud computing platform, such as an Open Cloud (O-Cloud) 269, to perform network element lifecycle management, such as to instantiate a virtualized network element, via a cloud computing platform interface, such as an 02 interface. Such virtualized network elements can include, but are not limited to, the CU 280, the DU 285, the RU 287, and the near-RT RIC 259. In some implementations, the SMO framework 255 can communicate with hardware aspects of a 4G RAN, such as an Open eNB (O-eNB) 261, via an Ol interface. Additionally, in some implementations, the SMO framework 255 can communicate directly with one or more RUs 287 via an Ol interface. The SMO framework 255 can also include a non-RT RIC 257 configured to support functionality of the SMO framework 255.

[0085] The non-RT RIC 257 can be configured to include logical functions that enable non-real-time control and optimization of RAN elements and resources, including model training and update, AI / ML workflow or policy-based steering of applications / features in the near-RT RIC 259. The non-RT RIC 257 can be coupled to or in communication with the near-RT RIC 259, such as via an Al interface. The near-RT RIC 259 can be configured to include logical functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions by way of an interface, such as via an E2 interface, that connects one or more CUs 280, one or more DUs 285, or both, and an O-eNB with the near-RT RIC 259.

[0086] In some implementations, to generate AI / ML models to be deployed in the near-RT RIC 259, the non-RT RIC 257 can receive parameters or external enrichment information from an external server. Such information can be utilized by the near-RT RIC 259 and can be received at the SMO framework 255 or the non-RT RIC 257 from non-network data sources or from network functions. In some examples, the non-RT RIC 257 or the near-RT RIC 259 can be configured to tune RAN behavior or performance. For example, the non-RT RIC 257 can monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions by way of the SMO framework 255, such as via reconfiguration of Ol, or via creation of RAN management policies, such as Al policies.

[0087] Figure 3A 、 Figure 3B and Figure 3C A number of example components are illustrated by corresponding blocks, which can be combined in UE 302 (which can correspond to any of the UEs described herein), base station 304 (which can correspond to any of the base stations described herein), and network entity 306 (which can correspond to or embody any of the network functions described herein, including location server 230 and LMF 270, or alternatively can be independent from such network functions). For example, blocks can represent Figure 2A and Figure 2BThe depicted NG-RAN 220 and / or 5GC 210 / 260 infrastructure, such as a dedicated network, in support of operations as described herein. It will be appreciated that these components can be implemented in different implementations of different types of devices (e.g., in ASICs, in SoCs, etc.) in the communication system. The illustrated components can also be incorporated into other devices in the communication system. For example, other devices in the system can include components similar to those described as providing similar functionality. Also, a given device can contain one or more of the components. For example, a device can include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0088] The UE 302 and the base stations 304 each include one or more wireless wide area network (WWAN) transceivers 310 and 350, respectively, that provide the components (e.g., components for transmitting, for receiving, for measuring, for tuning, for preventing transmitting, etc.) for communicating over one or more wireless communication networks (not shown), such as an NR network, an LTE network, a GSM network, and / or the like. The WWAN transceivers 310 and 350 can each be connected to one or more antennas 316 and 356, respectively, for communicating with other network nodes, such as other UEs, access points, base stations (e.g., eNBs, gNBs), etc., via the wireless communication medium (e.g., a set of time / frequency resources in a particular frequency spectrum) according to at least one designated RAT (e.g., NR, LTE, GSM, etc.). The WWAN transceivers 310 and 350 can be variously configured for transmitting and encoding signals 318 and 358 (e.g., messages, indications, information, and / or the like), respectively, and, conversely, for receiving and decoding signals 318 and 358 (e.g., messages, indications, information, pilots, and / or the like), respectively, in accordance with the designated RAT. Specifically, the WWAN transceivers 310 and 350 include one or more transmitters 314 and 354, respectively, for transmitting and encoding signals 318 and 358, respectively, and one or more receivers 312 and 352, respectively, for receiving and decoding signals 318 and 358, respectively.

[0089] At least in some cases, the UE 302 and the base stations 304 each also include one or more short-range wireless transceivers 320 and 360, respectively. The short-range wireless transceivers 320 and 360 can be connected to one or more antennas 326 and 366, respectively, and provide components (e.g., components for transmitting, for receiving, for measuring, for tuning, for preventing transmitting, etc.) for communicating with other communication devices over a short-range wireless ® , ZIGBEE ® , Z-WAVE ®The short-range transceivers 320 and 360 can be configured in various ways to communicate with other network nodes (such as other UEs, access points, base stations, etc.) using PC5, Dedicated Short Range Communication (DSRC), Wireless Access for Vehicle Environments (WAVE), Near Field Communication (NFC), Ultra Wideband (UWB), etc.) and other network nodes (such as other UEs, access points, base stations, etc.). These components include (e.g., components for transmitting, components for receiving, components for measuring, components for tuning, components for blocking transmission, etc.). The short-range transceivers 320 and 360 can be configured in different ways to transmit and encode signals 328 and 368 (e.g., messages, indications, information, etc.) according to a specified RAT, and conversely, to receive and decode signals 328 and 368 (e.g., messages, indications, information, pilots, etc.). Specifically, the short-range transceivers 320 and 360 each include: one or more transmitters 324 and 364 for transmitting and encoding signals 328 and 368, respectively; and one or more receivers 322 and 362 for receiving and decoding signals 328 and 368, respectively. As specific examples, the short-range wireless transceivers 320 and 360 can be Wi-Fi transceivers, Bluetooth transceivers, etc. ® Transceiver, Zigbee ® and / or Z-WAVE ® Transceivers, NFC transceivers, UWB transceivers, or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceivers.

[0090] In at least some cases, UE 302 and base station 304 also include satellite signal receivers 330 and 370. Satellite signal receivers 330 and 370 may be connected to one or more antennas 336 and 376, respectively, and may provide components for receiving and / or measuring satellite positioning / communication signals 338 and 378, respectively. Where satellite signal receivers 330 and 370 are satellite positioning system receivers, satellite positioning / communication signals 338 and 378 may be Global Positioning System (GPS) signals, Global Navigation Satellite System (GLONASS) signals, etc. ® The signals received by satellite signal receivers 330 and 370 may include Galileo signals, BeiDou signals, Indian Regional Navigation Satellite System (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. When satellite signal receivers 330 and 370 are non-terrestrial network (NTN) receivers, satellite positioning / communication signals 338 and 378 may be communication signals originating from a 5G network (e.g., carrying control and / or user data). Satellite signal receivers 330 and 370 may include any suitable hardware and / or software for receiving and processing satellite positioning / communication signals 338 and 378, respectively. Satellite signal receivers 330 and 370 may request information and operations from other systems as needed, and in at least some cases, perform calculations using measurements obtained by any suitable satellite positioning system algorithm to determine the locations of UE 302 and base station 304, respectively.

[0091] The base stations 304 and network entities 306 each include one or more network transceivers 380 and 390, respectively, which provide means for communicating (e.g., means for transmitting, means for receiving, etc.) with other network entities (e.g., other base stations 304, other network entities 306) over a network. For example, a base station 304 can employ the one or more network transceivers 380 to communicate with other base stations 304 or network entities 306 over one or more wired or wireless backhaul links. As another example, a network entity 306 can employ the one or more network transceivers 390 to communicate with one or more base stations 304 over one or more wired or wireless backhaul links, or with other network entities 306 over one or more wired or wireless core network interfaces.

[0092] Transceivers can be configured to communicate over wired or wireless links. Transceivers, whether wired or wireless, include transmitter circuitry (e.g., the transmitters 314, 324, 354, 364) and receiver circuitry (e.g., the receivers 312, 322, 352, 362). In some implementations, the transceivers can be integrated devices (e.g., implementing the transmitter circuitry and receiver circuitry in a single device), can include separate transmitter circuitry and separate receiver circuitry in some implementations, or can be implemented in other manners in other implementations. The transmitter circuitry and receiver circuitry of wired transceivers (e.g., the network transceivers 380 and 390 in some implementations) can be coupled to one or more wired network interface ports. The wireless transmitter circuitry (e.g., the transmitters 314, 324, 354, 364) can include or be coupled to a plurality of antennas (e.g., the antennas 316, 326, 356, 366), such as an antenna array, which permits the respective device (e.g., the UE 302, the base station 304) to perform transmit “beamforming,” as described herein. Similarly, the wireless receiver circuitry (e.g., the receivers 312, 322, 352, 362) can include or be coupled to a plurality of antennas (e.g., the antennas 316, 326, 356, 366), such as an antenna array, which permits the respective device (e.g., the UE 302, the base station 304) to perform receive beamforming, as described herein. In an aspect, the transmitter circuitry and receiver circuitry can share the same plurality of antennas (e.g., the antennas 316, 326, 356, 366), such that the respective device can only receive or transmit at a given time, not both at the same time. Wireless transceivers (e.g., the WWAN transceivers 310 and 350, the short-range wireless transceivers 320 and 360) can also include a network listen module (NLM) or the like for performing various measurements.

[0093] As used herein, various wireless transceivers (e.g., transceivers 310, 320, 350, and 360 in some implementations, as well as network transceivers 380 and 390) and wired transceivers (e.g., network transceivers 380 and 390 in some implementations) can generally be referred to as “transceivers,” “at least one transceiver,” or “one or more transceivers.” Thus, whether a particular transceiver is a wired or wireless transceiver can be inferred from the type of communication being performed. For example, backhaul communications between network devices or servers typically involve signaling via wired transceivers, while wireless communications between a UE (e.g., UE 302) and a base station (e.g., base station 304) will typically involve signaling via wireless transceivers.

[0094] The UEs 302, the base stations 304, and the network entities 306 also include other components that can be used in conjunction with the operations disclosed herein. The UEs 302, the base stations 304, and the network entities 306 each include one or more processors 332, 384, and 394, for providing functionality, such as wireless communication functionality, and for providing other processing functionality. Accordingly, the processors 332, 384, and 394 can provide means for processing, such as means for determining, means for calculating, means for receiving, means for transmitting, means for indicating, etc. In an aspect, the processors 332, 384, and 394 can include, for example, one or more general purpose processors, multi-core processors, central processing units (CPUs), ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGAs), other programmable logic devices or processing circuitry, or various combinations thereof.

[0095] The UE 302, the base stations 304, and the network entity 306 each include memory circuitry implementing memory 340, 386, and 396 (e.g., including a memory device, respectively) to maintain information (e.g., information indicative of reserved resources, thresholds, parameters, etc.). Accordingly, the memory 340, 386, and 396 can provide a means for storing, a means for retrieving, a means for maintaining, etc. In some cases, the UE 302, the base stations 304, and the network entity 306 can each include a positioning component 342, 388, and 398, respectively. The positioning component 342, 388, and 398 can be hardware circuits that are part of, or coupled to, the processors 332, 384, and 394, respectively, which, when executed, cause the UE 302, the base stations 304, and the network entity 306 to perform the functionality described herein. In other aspects, the positioning component 342, 388, and 398 can be external to the processors 332, 384, and 394 (e.g., part of a modem processing system, integrated with another processing system, etc.). Alternatively, the positioning component 342, 388, and 398 can be memory modules stored in the memory 340, 386, and 396, respectively, which, when executed by the processors 332, 384, and 394 (or a modem processing system, another processing system, etc.) cause the UE 302, the base stations 304, and the network entity 306 to perform the functionality described herein. Figure 3A Possible locations for the positioning component 342 are illustrated, which can be part of, for example, the one or more WWAN transceivers 310, the memory 340, the one or more processors 332, or any combination thereof, or can be a standalone component. Figure 3B Possible locations for the positioning component 388 are illustrated, which can be part of, for example, the one or more WWAN transceivers 350, the memory 386, the one or more processors 384, or any combination thereof, or can be a standalone component. Figure 3C Possible locations for the positioning component 398 are illustrated, which can be part of, for example, the one or more network transceivers 390, the memory 396, the one or more processors 394, or any combination thereof, or can be a standalone component.

[0096] The UE 302 can include one or more sensors 344 coupled to the one or more processors 332 to provide means for sensing or detecting movement and / or orientation information unrelated to motion data derived from signals received by the one or more WWAN transceivers 310, the one or more short-range wireless transceivers 320, and / or the satellite signal receiver 330. By way of example, the sensors 344 can include an accelerometer (e.g., a micro-electrical mechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), and / or any other type of movement detection sensor. Moreover, the sensors 344 can include multiple different types of devices and combine their outputs in order to provide motion information. For example, the sensors 344 can use a combination of a multi-axis accelerometer and an orientation sensor to provide the ability to calculate positioning in two-dimensional (2D) and / or three-dimensional (3D) coordinate systems.

[0097] Further, the UE 302 includes a user interface 346 that provides means for providing indications (e.g., audible and / or visual indications) to a user and / or for receiving user input (e.g., upon the user actuating a sensing device, such as a keypad, a touch screen, a microphone, etc.). Although not shown, the base station 304 and the network entity 306 can also include user interfaces.

[0098] Referring to the one or more processors 384 in more detail, in the downlink, IP packets from the network entity 306 can be provided to the processor 384. The one or more processors 384 can implement functionality for a RRC layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The one or more processors 384 can provide RRC layer functionality associated with broadcasting of system information (e.g., master information block (MIB), system information blocks (SIBs)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with the transfer of upper layer PDUs, error correction through automatic repeat request (ARQ), concatenation, segmentation, and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization.

[0099] The transmitter 354 and receiver 352 can implement layer 1 (LI) functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, can include error detection on the transport channels, forward error correction (FEC) coding / decoding of the transport channels, interleaving, rate matching, mapping to physical channels, modulation / demodulation of physical channels, and MIMO antenna processing. The transmitter 354 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols can then be split into parallel streams. Each stream can then be mapped to a orthogonal frequency division multiplexing (OFDM) subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and / or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM symbol stream is spatially precoded to produce multiple spatial streams if multiple spatial streams are

[0100] At the UE 302, the receiver 312 receives a signal through its respective antenna 316. The receiver 312 recovers information modulated onto an RF carrier and provides the information to the one or more processors 332. The transmitter 314 and the receiver 312 implement layer 1 functionality associated with various signal processing functions. The receiver 312 can perform spatial processing on the information to recover any spatial streams destined for the UE 302. If multiple spatial streams are destined for the UE 302, they can be combined by the receiver 312 into a single OFDM symbol stream. The receiver 312 then converts the OFDM symbol stream from the time-domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 304. These soft decisions can be based on channel estimates computed by the channel estimator. The soft decisions are then decoded and de-interleaved to recover the data and control signals that were originally transmitted on the physical channel. The data and control signals are then provided to the one or more processors 332, which implement layer 3 (L3) and layer 2 (L2) functionality.

[0101] In the downlink, the one or more processors 332 provide demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the core network. The one or more processors 332 are also responsible for error detection.

[0102] Similar to the functionality described in connection with the downlink transmission by the base station 304, the one or more processors 332 provide RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression / decompression, and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transmission channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), priority handling, and logical channel prioritization.

[0103] Channel estimates derived by the channel estimator from the reference signals or feedback transmitted by the base station 304 can be used by the transmitter 314 to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the transmitter 314 can be provided to different antenna 316. The transmitter 314 can modulate an RF carrier with a respective spatial stream for transmission.

[0104] The uplink transmissions are processed at the base station 304 in a manner similar to that described in connection with the receiver function at the UE 302. The receiver 352 receives information from the respective antennas 356. The receiver 352 recovers information modulated onto an RF carrier and provides the information to the one or more processors 384.

[0105] In the uplink, the one or more processors 384 provide demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 302. IP packets from the one or more processors 384 can be provided to the core network. The one or more processors 384 are also responsible for error detection.

[0106] For convenience, the UE 302, base station 304, and / or network entity 306 are referred to as Figure 3A , Figure 3B and Figure 3CThe UE 302, the base station 304, or both, can include various components not specifically depicted in FIG. 3, such as the network controllers, memory, power supplies, and other components used to fabricate the respective devices. These components are not specifically depicted in FIG. 3 but can be included in one or both of the UE 302 and the base station 304. The UE 302, the base station 304, or both, can include various components, which can be configured according to various examples described herein. However, it is to be understood that the illustrated components can have different functionality in different designs. In particular, Figures 3A-3C Various components in the UE 302, the base station 304, or both, can be optional in alternative configurations, and various aspects include configurations that can vary due to design choice, cost, use of the device, or other considerations. For example, in the case of the UE 302, Figure 3A , a particular implementation of the UE 302 can omit the WWAN transceiver 310 (e.g., a wearable device or a tablet computer or personal computer (PC) or laptop can have Wi-Fi and / or Bluetooth ® capabilities without cellular capability), or can omit the short-range wireless transceiver 320 (e.g., cellular-only, etc.), or can omit the satellite signal receiver 330, or can omit the sensor 344, etc. In another example, in the case of the base station 304, Figure 3B , a particular implementation of the base station 304 can omit the WWAN transceiver 350 (e.g., a Wi-Fi “hotspot” access point without cellular capability), or can omit the short-range wireless transceiver 360 (e.g., cellular-only, etc.), or can omit the satellite signal receiver 370, etc. For brevity, examples of various alternative configurations are not provided herein, but would be readily understood by one of skill in the art.

[0107] The various components of the UE 302, the base station 304, and the network entity 306 can be communicatively coupled to each other by data buses 334, 382, and 392, respectively. In an aspect, the data buses 334, 382, and 392 can form, or be part of, a communication interface of the UE 302, the base station 304, and the network entity 306, respectively. For example, in cases where different logical entities are embodied in the same device (e.g., gNB and location server functionality combined into the same base station 304), the data buses 334, 382, and 392 can provide for communication between the different logical entities.

[0108] Figure 3A , Figure 3B and Figure 3C The components of the UE 302, the base station 304, and the network entity 306 can be implemented in various ways. In some implementations, Figure 3A , Figure 3B and Figure 3CThe components of the network entity 306 can be implemented in one or more circuits such as, for example, one or more processors and / or ASICs (which can include one or more processors). Here, each circuit can use and / or incorporate at least one memory component for storing information or executable code used by the circuit to provide the functionality. For example, some or all of the functionality represented by blocks 390 through 398 can be implemented by a processor and memory component of the network entity 306 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor component). For simplicity, various operations, acts, and / or functions are described herein as being performed by a UE, a base station, a network entity, etc. However, as will be appreciated, such operations, acts and / or functions can actually be performed by specific components or combinations of components (such as the processors 332, 384, 394, transceivers 310, 320, 350, and 360, memories 340, 386, and 396, positioning components 342, 388, and 398, etc.) of the UE 302, base station 304, network entity 306, etc.

[0109] In some designs, the network entity 306 can be implemented as a component of a core network. In other designs, the network entity 306 can be distinct from the operation of a network operator or cellular network infrastructure (e.g., NG RAN 220 and / or 5GC 210 / 260). For example, the network entity 306 can be a component of a private network that can be configured to communicate with the UE 302 via the base station 304 or independent of the base station 304 (e.g., through a non-cellular communication link such as Wi-Fi).

[0110] After the random access procedure, the UE is in an RRC connected state. The RRC protocol is used over the air interface between the UE and the base station. The main functions of the RRC protocol include connection setup and release functions, broadcast of system information, radio bearer setup, reconfiguration, release, RRC connection mobility procedures, paging notification and release, and outer loop power control. In LTE, the UE can be in one of two RRC states (connected or idle), but in NR, the UE can be in one of three RRC states (connected, idle, or inactive). The different RRC states have different radio resources associated with the states that the UE can use when in a given state. Note that, as above, the different RRC states are typically capitalized; however, this is not a requirement, and the states can also be written in lower case.

[0111] Figure 4 is a diagram 400 of the different RRC states (also referred to as RRC modes) available in NR in accordance with aspects of the present disclosure. When the UE powers on, the UE initially is in an RRC disconnected / idle state 410. After a random access procedure, the UE moves to an RRC connected state 420. If there is no activity at the UE for a short time, the UE can suspend its session by moving to an RRC inactive state 430. The UE can resume its session by performing a random access procedure to transition back to the RRC connected state 420. Thus, the UE needs to perform a random access procedure to transition to the RRC connected state 420 regardless of whether the UE is in the RRC idle state 410 or the RRC inactive state 430.

[0112] Operations performed in the RRC idle state 410 include public land mobile network (PLMN) selection, broadcast of system information, cell reselection mobility, paging for mobile terminated data (initiated and managed by 5GC), discontinuous reception (DRX) for core network paging (configured by non-access stratum (NAS)). Operations performed in the RRC connected state 420 include 5GC (e.g., 5GC 260) and NG-RAN (e.g., NG-RAN 220) connection setup (both control plane and user plane), UE context storage at the NG-RAN and the UE, NG-RAN knowledge of the cell to which the UE belongs, transfer of unicast data to / from the UE, and network-controlled mobility. Operations performed in the RRC inactive state 430 include broadcast of system information, cell reselection for mobility, paging (initiated by NG-RAN), RAN-based notification area (RNA) management (by NG-RAN), DRX for RAN paging (configured by NG-RAN), 5GC and NG-RAN connection setup for the UE (both control plane and user plane), UE context storage in the NG-RAN and the UE, and NG-RAN knowledge of the RNA to which the UE belongs.

[0113] NR supports multiple cellular network-based positioning techniques, including downlink-based, uplink-based, and downlink-and-uplink-based positioning methods. Downlink-based positioning methods include observed time difference of arrival (OTDOA) in LTE, downlink time difference of arrival (DL-TDOA) in NR, and downlink angle of departure (DL-AoD) in NR. Figure 5 Examples of various positioning methods in accordance with aspects of the disclosure are illustrated. In an OTDOA or DL-TDOA positioning procedure illustrated in scenario 510, a UE measures the differences between the times of arrival (ToAs) of reference signals (e.g., positioning reference signals (PRS)) received from pairs of base stations (referred to as reference signal time difference (RSTD) or time difference of arrival (TDOA) measurements) and reports these differences to a positioning entity. More specifically, the UE receives the identifiers (IDs) of a reference base station (e.g., a serving base station) and multiple non-reference base stations in assistance data. The UE then measures the RSTD between the reference base station and each non-reference base station. Based on the known locations of the involved base stations and the RSTD measurements, a positioning entity (e.g., a UE for UE-based positioning or a location server for UE-assisted positioning) can estimate the location of the UE.

[0114] For DL-AoD positioning illustrated in scenario 520, a positioning entity determines the angles between a UE and the transmitting base stations using measurement reports from the UE of received signal strength measurements for multiple downlink transmit beams. The positioning entity can then estimate the location of the UE based on the determined angles and the known locations of the transmitting base stations.

[0115] Uplink-based positioning methods include uplink time difference of arrival (UL-TDOA) and uplink angle of arrival (UL-AoA). UL-TDOA is similar to DL-TDOA but is based on uplink reference signals (e.g., sounding reference signals (SRS)) transmitted by the UE to multiple base stations. Specifically, the UE transmits one or more uplink reference signals, which are measured by a reference base station and multiple non-reference base stations. Each base station then reports the time of reception of the reference signal (referred to as the relative time of arrival (RTOA)) to a positioning entity (e.g., a location server) that knows the locations and relative timings of the involved base stations. Based on the reported RTOA of the reference base station and the reported RTOA of each non-reference base station, the known locations of the base stations, and their known timing offsets, the positioning entity can estimate the location of the UE using TDOA.

[0116] For UL-AoA positioning, one or more base stations measure the received signal strength of one or more uplink reference signals (e.g., SRS) received from a UE on one or more uplink receive beams. The positioning entity uses the signal strength measurements and the angles of the receive beams to determine an angle between the UE and the base station. Based on the determined angle and the known locations of the base stations, the positioning entity can then estimate the location of the UE.

[0117] Downlink and uplink based positioning methods include Enhanced Cell-ID (E-CID) positioning and multi-round trip time (RTT) positioning (also referred to as “multi-cell RTT” and “multi-RTT”). In an RTT procedure, a first entity (e.g., a base station or a UE) transmits a first RTT-related signal (e.g., a PRS or an SRS) to a second entity (e.g., a UE or a base station), which transmits a second RTT-related signal (e.g., an SRS or a PRS) back to the first entity. Each entity measures the time difference between the time of arrival (ToA) of the received RTT-related signal and the transmission time of the transmitted RTT-related signal. This time difference is referred to as a receive-to-transmit (Rx-Tx) time difference. The Rx-Tx time difference measurement can be made or adjusted to include only the time difference between the closest time slot boundaries of the received and transmitted signals. Both entities can then communicate their Rx-Tx time difference measurements to a location server (e.g., LMF 270), which computes the round trip propagation time (i.e., RTT) between the two entities from the two Rx-Tx time difference measurements (e.g., as the sum of the two Rx-Tx time difference measurements). Alternatively, one entity can communicate its Rx-Tx time difference measurement to the other entity, which then computes the RTT. The distance between the two entities can be determined from the RTT and the known speed of signal (e.g., the speed of light). For multi-RTT positioning illustrated by scenario 530, a first entity (e.g., a UE or a base station) performs an RTT positioning procedure with multiple second entities (e.g., multiple base stations or UEs) to enable determination of the location of the first entity (e.g., using multilateration) based on the distances to the second entities and the known locations of the second entities. RTT and multi-RTT methods can be combined with other positioning techniques, such as UL-AoA and DL-AoD, to improve location accuracy, as illustrated by scenario 540.

[0118] The E-CID positioning method is based on radio resource management (RRM) measurements. In E-CID, the UE reports the serving cell ID, timing advance (TA), and identifiers of detected neighbor base stations, estimated timing, and signal strengths. The location of the UE is then estimated based on this information and the known locations of the base stations.

[0119] To assist in positioning operations, a location server (e.g., location server 230, LMF 270, SLP 272) can provide assistance data to a UE. For example, the assistance data can include identifiers of base stations (or cells / TRPs of base stations) from which to measure reference signals, reference signal configuration parameters (e.g., including a number of consecutive time slots comprising a PRS, a periodicity of consecutive time slots comprising a PRS, a muting sequence, a frequency hopping sequence, a reference signal identifier, a reference signal bandwidth, etc.), and / or other parameters applicable to a particular positioning method. Alternatively, the assistance data can originate directly from the base stations themselves (e.g., in periodically broadcasted overhead messages, etc.). In some cases, a UE can be able to detect neighboring network nodes without the use of assistance data.

[0120] In the case of OTDOA or DL-TDOA positioning procedures, the assistance data can also include an expected RSTD value and an associated uncertainty or search window around the expected RSTD. In some cases, the expected RSTD can have a value range of + / - 500 microseconds (ps). In some cases, the uncertainty of the expected RSTD can have a value range of + / - 32 ps when any of the resources used for positioning measurements are in FR1. In other cases, the uncertainty of the expected RSTD can have a value range of + / - 8 ps when all of the resources used for positioning measurements are in FR2.

[0121] A location estimate can be referred to by other names, such as a position estimate, location, fix, fix, etc. A location estimate can be geodetic and include coordinates (e.g., latitude, longitude, and possibly altitude), or can be civic and include a street address, postal address, or some other spoken description of a location. A location estimate can be further defined relative to some other known location or defined in absolute terms (e.g., using latitude, longitude, and possibly altitude). A position estimate can include an expected error or uncertainty (e.g., by including an area or volume within which the location is expected to be included with some specified or default confidence).

[0122] Various frame structures can be used to support downlink and uplink transmissions between network nodes (e.g., base stations and UEs). Figure 6 is a diagram 600 illustrating example frame structures in accordance with aspects of the present disclosure. The frame structures can be downlink or uplink frame structures. Other wireless communication technologies can have different frame structures and / or different channels.

[0123] LTE (and in some cases NR) utilizes orthogonal frequency division multiplexing (OFDM) with a cyclic prefix on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. Specifically, LTE and NR divide the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, etc. Each subcarrier can be modulated with data. In general, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing of the adjacent subcarriers can be fixed, and the total number of subcarriers (K) can be dependent on the system bandwidth. The spacing of the subcarriers can be 15 kilohertz (kHz) in some cases. The total number of subcarriers in some cases can be 1200 for a 20 megahertz (MHz) system bandwidth. The system bandwidth can be partitioned into sub-bands. For example, a sub-band can cover 1.08 MHz (i.e., 6 resource blocks), and there can be 1, 2, 4, 8, or 16 sub-bands for a 1.25, 2.5, 5, 10, or 20 MHz system bandwidth, respectively.

[0124] LTE supports a single numerology (subcarrier spacing (SCS), symbol length, etc.). In contrast, NR can support multiple numerologies (µ), e.g., 15 kHz (µ=0), 30 kHz (µ=1), 60 kHz (µ=2), 120 kHz (µ=3), and 240 kHz (µ=4) or larger subcarrier spacing can be available. In each subcarrier spacing, there are 14 symbols per slot. For 15 kHz SCS (µ=0), there is one slot per subframe, 10 slots per frame, a slot duration of 1 millisecond (ms), a symbol duration of 66.7 microseconds (µs), and a maximum nominal system bandwidth (in MHz) with a 4K FFT size of 50. For 30 kHz SCS (µ=1), there are two slots per subframe, 20 slots per frame, a slot duration of 0.5 ms, a symbol duration of 33.3 µs, and a maximum nominal system bandwidth (in MHz) with a 4K FFT size of 100. For 60 kHz SCS (µ=2), there are four slots per subframe, 40 slots per frame, a slot duration of 0.25 ms, a symbol duration of 16.7 µs, and a maximum nominal system bandwidth (in MHz) with a 4K FFT size of 200. For 120 kHz SCS (µ=3), there are eight slots per subframe, 80 slots per frame, a slot duration of 0.125 ms, a symbol duration of 8.33 µs, and a maximum nominal system bandwidth (in MHz) with a 4K FFT size of 400. For 240 kHz SCS (µ=4), there are 16 slots per subframe, 160 slots per frame, a slot duration of 0.0625 ms, a symbol duration of 4.17 µs, and a maximum nominal system bandwidth (in MHz) with a 4K FFT size of 800.

[0125] In Figure 6 examples, a numerology of 15 kHz is used. Thus, in the time domain, a frame of 10 ms is divided into 10 equal size subframes with each subframe of 1 ms and each subframe including one slot. In Figure 6 time is represented horizontally (on the X axis) with time increasing from left to right, while frequency is represented vertically (on the Y axis) with frequency increasing (or decreasing) from bottom to top.

[0126] A resource grid can be used to represent the time slots, each time slot including one or more time-concurrent resource blocks (RBs) (also referred to as physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into multiple resource elements (REs). An RE can correspond to one symbol length in the time domain and one subcarrier in the frequency domain. In Figure 6An RB can contain 12 consecutive subcarriers in the frequency domain and seven consecutive symbols in the time domain for normal cyclic prefix, or six consecutive symbols in the time domain for extended cyclic prefix, for a total of 84 or 72 REs, respectively. The number of bits carried by each RE depends on the modulation scheme.

[0127] Some of the REs can carry reference (pilot) signals (RS). These reference signals can include positioning reference signals (PRS), tracking reference signals (TRS), phase tracking reference signals (PTRS), cell-specific reference signals (CRS), channel state information reference signals (CSI-RS), demodulation reference signals (DMRS), primary synchronization signals (PSS), secondary synchronization signals (SSS), synchronization signal blocks (SSBs), sounding reference signals (SRS), etc., depending on whether the illustrated frame structure is used for uplink or downlink communications. Figure 6 Example locations of REs carrying reference signals are illustrated (labeled “R”).

[0128] A set of resource elements (REs) used for the transmission of a PRS is referred to as a “PRS resource.” The set of resource elements can span multiple PRBs in the frequency domain and “N” (such as 1 or more) consecutive symbols within a slot in the time domain. In a given OFDM symbol in the time domain, a PRS resource occupies consecutive PRBs in the frequency domain.

[0129] The transmission of a PRS resource within a given PRB has a particular comb size (also referred to as “comb density”). The comb size “N” represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the PRS resource configuration. Specifically, for a comb size “N,” the PRS is transmitted in every Nth subcarrier of one symbol of the PRB. For example, for comb-4, for each symbol of the PRS resource configuration, the REs corresponding to every fourth subcarrier (such as subcarriers 0, 4, 8) are used to transmit the PRS of the PRS resource. Currently, comb sizes of comb-2, comb-4, comb-6, and comb-12 are supported for DL-PRS. Figure 6 An example PRS resource configuration for comb-4 (which spans four symbols) is illustrated. That is, the locations of the shaded REs (labeled “R”) indicate a comb-4 PRS resource configuration.

[0130] Currently, DL-PRS resources use a full frequency domain interlaced pattern that can span 2, 4, 6, or 12 consecutive symbols within a slot. A DL-PRS resource can be configured in any downlink or flexible (FL) symbol of a slot that is configured by higher layers. There can be a constant energy per resource element (EPRE) for all REs of a given DL-PRS resource. The following are the per-symbol frequency offsets for comb sizes 2, 4, 6, and 12 over 2, 4, 6, and 12 symbols. 2-symbol comb-2: {0, 1}; 4-symbol comb-2: {0, 1, 0, 1}; 6-symbol comb-2: {0, 1, 0, 1, 0, 1}; 12-symbol comb-2: {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}; 4-symbol comb-4: {0, 2, 1, 3} (as in the example of Figure 6 {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}; 6-symbol comb-6: {0, 3, 1, 4, 2, 5}; 12-symbol comb-6: {0, 3, 1, 4, 2, 5, 0, 3, 1, 4, 2, 5}; and 12-symbol comb-12: {0, 6, 3, 9, 1, 7, 4, 10, 2, 8, 5, 11}.

[0131] A “PRS resource set” is a set of PRS resources used to transmit PRS signals, where each PRS resource has a PRS resource ID. Further, the PRS resources in a PRS resource set are associated with the same TRP. A PRS resource set is identified by a PRS resource set ID and is associated with a particular TRP (identified by a TRP ID). Further, the PRS resources in a PRS resource set have the same periodicity, common muting pattern configuration, and same repetition factor (such as “PRS-ResourceRepetitionFactor”) across slots. The periodicity is the time from a first repetition of a first PRS resource of a first PRS instance to the same first repetition of the same first PRS resource of a next PRS instance. The periodicity can have a length selected from {2^µ*{4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots, where µ = 0, 1, 2, 3. The repetition factor can have a length selected from {1, 2, 4, 6, 8, 16, 32} slots.

[0132] A PRS resource ID in a PRS resource set is associated with a single beam (or beam ID) transmitted from a single TRP (where one TRP can transmit one or more beams). That is, each PRS resource in a PRS resource set can be transmitted on a different beam, and thus, a “PRS resource” (or simply “resource”) can also be referred to as a “beam.” Note that this does not have any implications as to whether the TRP and beam on which the PRS is transmitted are known to the UE.

[0133] A “PRS instance” or “PRS occasion” is one instance of a periodically repeating time window (such as a set of one or more consecutive slots) in which PRS is expected to be transmitted. A PRS occasion can also be referred to as a “PRS positioning occasion,” “PRS positioning instance,” “positioning occasion,” “positioning instance,” “positioning repetition,” or simply “occasion,” “instance,” or “repetition.”

[0134] A “positioning frequency layer” (also simply referred to as a “frequency layer”) is a set of one or more PRS resource sets across one or more TRPs that have the same values for certain parameters. Specifically, the set of PRS resource sets have the same subcarrier spacing and cyclic prefix (CP) type (meaning that all numerologies supported for physical downlink shared channel (PDSCH) are also supported for PRS), the same Point A, the same value of downlink PRS bandwidth, the same starting PRB (and center frequency), and the same comb size. The Point A parameter takes the value of the parameter “ARFCN-ValueNR” (where “ARFCN” stands for “absolute radio frequency channel number”) and is an identifier / code that specifies a pair of physical radio channels for transmission and reception. The downlink PRS bandwidth can have a granularity of four PRBs, with a minimum value of 24 PRBs and a maximum value of 272 PRBs. Currently, up to four frequency layers have been defined, and up to two PRS resource sets per TRP per frequency layer can be configured.

[0135] The concept of a frequency layer is somewhat analogous to the concepts of component carriers and bandwidth parts (BWPs), but with the difference that component carriers and BWPs are used by one base station (or macrocell base station and small cell base station) to transmit data channels, whereas a frequency layer is used by several (typically three or more) base stations to transmit PRS. A UE can indicate the number of frequency layers that it can support when the UE communicates its positioning capabilities to the network, such as during an LTE Positioning Protocol (LPP) session. For example, a UE can indicate whether it can support one or four positioning frequency layers.

[0136] In an aspect, Figure 6The reference signal carried on the REs marked "R" can be a SRS. SRS transmitted by a UE can be used by a base station to obtain channel state information (CSI) for the transmitting UE. CSI describes how RF signals propagate from the UE to the base station and represents the combined effects of scattering, attenuation, and power decay with distance. The system uses SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc.

[0137] The set of REs used for the transmission of SRS is referred to as an "SRS resource" and can be identified by the parameter "SRS-ResourceId." The set of resource elements can span multiple PRBs in the frequency domain and "N" (e.g., one or more) consecutive symbols within a slot in the time domain. In a given OFDM symbol, an SRS resource occupies one or more consecutive PRBs. An "SRS resource set" is a group of SRS resources used for the transmission of SRS signals and is identified by an SRS resource set ID ("SRS-ResourceSetId").

[0138] The transmission of an SRS resource within a given PRB has a specific comb size (also referred to as "comb density"). The comb size "N" represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the SRS resource configuration. Specifically, for a comb size "N," the SRS is transmitted in every Nth subcarrier of one symbol of a PRB. For example, for comb-4, for each symbol of the SRS resource configuration, the REs corresponding to every fourth subcarrier (such as subcarriers 0, 4, 8) are used to transmit the SRS of the SRS resource. In Figure 6 In the example of FIG. 3, the illustrated SRS is comb-4 spanning four symbols. That is, the locations of the shaded SRS REs indicate a comb-4 SRS resource configuration.

[0139] Currently, SRS resources with comb size of comb-2, comb-4, or comb-8 can span 1, 2, 4, 8, or 12 consecutive symbols within a slot. The following are the per-symbol frequency offsets for the currently supported SRS comb patterns. 1-symbol comb-2: {0}; 2-symbol comb-2: {0, 1}; 2-symbol comb-4: {0, 2}; 4-symbol comb-2: {0, 1, 0, 1}; 4-symbol comb-4: {0, 2, 1, 3} (as in Figure 64-symbol comb-2: {0, 1, 0, 1}; 8-symbol comb-2: {0, 1, 0, 1, 0, 1, 0, 1}; 12-symbol comb-2: {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}; 4-symbol comb-4: {0, 2, 1, 0}; 8-symbol comb-4: {0, 2, 1, 0, 0, 2, 1, 0}; 12-symbol comb-4: {0, 2, 1, 0, 0, 2, 1, 0, 0, 2, 1, 0}; 4-symbol comb-8: {0, 4, 2, 0}; 8-symbol comb-8: {0, 4, 2, 0, 0, 4, 2, 0}; and 12-symbol comb-8: {0, 4, 2, 0, 0, 4, 2, 0, 0, 4, 2, 0}.

[0140] In general, as noted above, the UE transmits SRS to enable a receiving base station (a serving base station or a neighboring base station) to measure the channel quality (i.e., CSI) between the UE and the base station. However, SRS can also be specifically configured as an uplink positioning reference signal for uplink-based positioning procedures, such as uplink time difference of arrival (UL-TDOA), round trip time (RTT), uplink angle of arrival (UL-AoA), etc. As used herein, the term “SRS” can refer to SRS configured for channel quality measurement or SRS configured for positioning purposes. When it is necessary to distinguish between the two types of SRS, the former can be referred to herein as “SRS for communication” and / or the latter can be referred to as “SRS for positioning” or “positioning SRS.”

[0141] Several enhancements to the prior definition of SRS have been proposed for “SRS for positioning” (also referred to as “UL-PRS”), such as new staggering patterns within an SRS resource (in addition to single-symbol / comb-2), new comb types for SRS, new sequences for SRS, larger number of SRS resource sets per component carrier, and larger number of SRS resources per component carrier. In addition, the parameters “SpatialRelationInfo” and “PathLossReference” are to be configured based on a downlink reference signal or SSB from a neighboring TRP. Further, one SRS resource can be transmitted outside of an active BWP, and one SRS resource can span multiple component carriers. Also, SRS can be configured in RRC connected state and transmitted only within an active BWP. In addition, there can be no frequency hopping, no repetition factor, single antenna port, and new lengths of SRS (e.g., 8 and 12 symbols). There can also be open loop power control and no closed loop power control, and comb-8 (i.e., SRS transmitted every eighth subcarrier in the same symbol) can be used. Finally, a UE can transmit from multiple SRS resources through the same transmit beam for UL-AoA. All of these are features outside of the current SRS framework, which is configured by RRC higher layer signaling (and potentially triggered or activated by MAC control element (MAC-CE) or downlink control information (DCI)).

[0142] Note that the terms “positioning reference signal” and “PRS” generally refer to specific reference signals used for positioning in NR and LTE systems. However, as used herein, the terms “positioning reference signal” and “PRS” can also refer to any type of reference signal that can be used for positioning, such as but not limited to: PRS as defined in LTE and NR, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, etc. Furthermore, the terms “positioning reference signal” and “PRS” can refer to downlink positioning reference signals, uplink positioning reference signals, or sidelink positioning reference signals, unless otherwise indicated by the context. If further differentiation of the type of PRS is needed, downlink positioning reference signals can be referred to as “DL-PRS”, uplink positioning reference signals (e.g., SRS for positioning, i.e., PTRS) can be referred to as “UL-PRS”, and sidelink positioning reference signals can be referred to as “SL-PRS”. Furthermore, for signals that can be transmitted in downlink, uplink, and / or sidelink (e.g., DMRS), these signals can be prepended with “DL”, “UL”, or “SL” to differentiate the direction. For example, “UL-DMRS” can be different from “DL-DMRS”.

[0143] Low power high accuracy positioning (LPHAP) techniques have been introduced that permit a UE to perform positioning operations while in RRC inactive state. With small data transmission (SDT) features, a UE can also transmit data and / or NAS signaling while remaining in RRC inactive state, allowing the UE to participate in downlink and uplink based and / or uplink based positioning procedures, not just downlink based positioning procedures.

[0144] The deferred mobile terminated location request (MT-LR) procedure provides an efficient means for location tracking of mobile devices or assets. In the initialization phase, the target device can be provided with positioning instructions (e.g., positioning method to use, QoS, etc.) and possibly assistance data. The target device then monitors for event occurrences, performs location measurements upon detecting an event, and provides the location results to the network. Multiple event types can be supported, such as entering, leaving, or staying within a predefined geographical area, moving more than a certain predefined distance from a previous location, or periodic location. Procedures have been defined to allow the UE to remain in RRC inactive state during the positioning measurement and event reporting phase.

[0145] Figure 7A and Figure 7BAn example deferred mobile terminating location request (MT-LR) procedure for downlink and uplink based positioning methods (e.g., multi-RTT) is illustrated in accordance with aspects of the present disclosure. The procedure consists of two event reports: Event Report #1 (Stage 3-10) for requesting / configuring SRS for positioning as Figure 7A illustrated, and Event Report #2 (Stage 12-16) for reporting position measurements as Figure 7B illustrated.

[0146] At Stage 1, Stage 1-21 of the deferred 5GC-MT-LR procedure for periodic or triggered location events specified in 3GPP Technical Specification (TS) 23.273, clause 6.3.1, which is publicly available and incorporated herein by reference in its entirety, is performed. The LMF 270 can perform one or more positioning procedures at Stage 15 of the deferred 5GC-MT-LR procedure for periodic or triggered location events (Stage 15 of the deferred 5GC-MT-LR procedure for periodic or triggered location events specified in 3GPP TS 23.273, clause 6.3.1) to request and obtain UE 204 positioning capabilities or to provide any necessary assistance data to the target device. The location services (LCS) periodic triggered location invocation at Stage 16 of the deferred 5GC-MT-LR procedure for periodic or triggered location events (Stage 16 of the deferred 5GC-MT-LR procedure for periodic or triggered location events specified in 3GPP TS 23.273, clause 6.3.1) includes an embedded LPP Request Location Information message indicating allowed or required multi-RTT position measurements for each location event reported.

[0147] At some point in time, the last serving gNB releases the UE 204 from RRC connected to RRC inactive with an “RRCRelease” with “SuspendConfig”.

[0148] At Stage 2, the UE 204 monitors for the occurrence of the triggered or periodic event requested during Stage 1.

[0149] At stage 3, when the event is detected (or slightly earlier), the UE 204 transmits, via small data transmission (SDT), an RRC UL Information Transfer message containing the UL NAS transport message along with a RRC Resume Request to the receiving gNB. The UE 204 includes the LCS Event Report in the payload container of the UL NAS transport message, and the deferred routing identifier received during stage 1 in the additional information of the UL NAS transport message. The LCS Event Report includes an embedded LPP Request Assistance Data message with the IE “NR-Multi-RTT-RequestAssistanceData” and “nr-AdType” set to “ul-srs” to request UL-SRS for multi-RTT positioning. Note that the receiving gNB at stage 3 of the UE 204 execution can be the same or different from the last serving gNB where the UE 204 was released to RRC Inactive state.

[0150] At stage 4, the receiving gNB forwards the LCS Event Report with the LPP Request Assistance Data message to the serving AMF 264 in a Next Generation Application Protocol (NGAP) Uplink NAS Transport message. The AMF 264 determines the LMF 270 from the deferred routing identifier received in the additional information IE of the UL NAS transport message, and forwards the LCS Event Report with the embedded LPP message to the LMF 270 via the Namf_Communication_N1MessageNotify service operation. The AMF 264 also includes the payload container type and the related identifier set to the deferred routing identifier. Note that if the anchor gNB has not changed from the last serving gNB to the receiving gNB, the LCS Event Report can be forwarded from the receiving gNB to the last serving gNB via the Xn Application Protocol (XnAP) message RRC Transfer. Subsequent downlink / uplink messages can also be forwarded between the last serving gNB to the receiving gNB via the XnAP message RRC Transfer.

[0151] At stage 5, the LMF 270 transmits a New Radio Positioning Protocol Type A (NRPPa) Positioning Information Request message to the receiving gNB to request UL-SRS for the target device (i.e., the UE 204).

[0152] At stage 6, the receiving gNB determines the resources available for UL-SRS.

[0153] At stage 7, the receiving gNB provides the UL-SRS configuration information to the LMF 270 in a NRPPa Positioning Information Response message.

[0154] At stage 8, the LMF 270 transmits an NRPPa Measurement Request including the UL-SRS measurement configuration to the gNB group.

[0155] At stage 9, the LMF 270 transmits a supplemental service (SS) LCS event report acknowledgement to the receiving gNB. Then, at stage 9b, the receiving gNB provides the SS event report acknowledgement to the UE 204 via a subsequent DL SDT.

[0156] At stage 10, the receiving gNB transmits an “RRCRelease” message with “suspendConfig” to keep the UE 204 in RRC Inactive state. The “RRCRelease” message includes the UL-SRS configuration.

[0157] At stage 11, the UE 204 performs DL-PRS measurements and each configured TRP performs UL-SRS measurements.

[0158] At stage 12, the UE 204 transmits an RRC UL information transfer message containing an UL NAS transport message along with an RRC resume request via an SDT. The UE 204 includes the LCS event report and LPP Provide Location Information message in the payload container of the UL NAS transport message and the deferred routing identifier received during stage 1 in the additional information of the UL NAS transport message.

[0159] At stage 13, the receiving gNB transmits the LCS event report with the LPP Provide Location Information message in an NGAP uplink NAS transport message to the serving AMF 264. The AMF 264 determines the LMF 270 from the deferred routing identifier received in the additional information IE of the UL NAS transport message and forwards the LCS event report with the embedded LPP message to the LMF 270 via a trigger Namf_Communication_N1MessageNotify service operation. The AMF 264 also includes the payload container type and the related identifier set to the deferred routing identifier.

[0160] At stage 14, after performing the UL-SRS measurements, the gNB provides the UL measurements to the LMF 270 in an NRPPa Measurement Response message.

[0161] At stage 15, when all LPP Provide Location Information messages have been received, the LMF 270 transmits an SS LCS event report acknowledgement to the receiving gNB. Then, at stage 15b, the receiving gNB provides the SS event report acknowledgement to the UE 204 via a subsequent DL SDT.

[0162] At stage 16, the receiving gNB transmits an "RRCRelease" message with "suspendConfig" to keep the UE 204 in RRC Inactive state.

[0163] At stage 17, stages 28-31 of the deferred 5GC-MT-LR procedure for periodic or triggered location event specified in TS 23.273, clause 6.3.1 are performed.

[0164] In the foregoing procedure, whenever an event report is triggered (e.g., when a periodic timer expires), a new positioning SRS can be "negotiated" between the LMF and the serving / receiving gNB (as at stages 3-10 in Figure 7A This results in a large signaling activity for periodic events with a relatively small periodicity (e.g., 15 seconds to 30 seconds), for example, and thus additional latency and processing, which can also adversely affect the power consumption at the target device.

[0165] To reduce the amount of SRS configuration signaling, it has been proposed to pre-configure a positioning SRS. This assumes that a positioning SRS can be provided once, e.g., at stage 1 of the initialization phase of the deferred MT-LR procedure (stages 1-2 in Figure 7A The positioning SRS can then be activated when needed. Instead of transmitting an event report to the LMF 270 at stages 3 and 4 in Figure 7A The UE 204 can potentially transmit a request to activate the pre-configured positioning SRS directly to the NG-RAN 220 (receiving gNB) using lower layer signaling (e.g., MAC Control Element (CE) (MAC-CE)). In this case, stages 5-7 and 9a in Figure 7A may not be needed or can be simplified.

[0166] However, due to mobility, the UE can request "SRS activation" in a cell different from the cell from which the pre-configured positioning SRS has been received. In general, the SRS for positioning is UE- and location-specific. The positioning SRS configuration is currently only valid in the cell in which the UE has received the SRS configuration. This is due to the fact that the SRS configuration includes parameters that depend (at least roughly) on the UE location, such as spatial relation information and path loss reference information (both are provided for neighboring cells, and the neighboring cells are typically different for different serving cells), and information determined by the receiving / serving gNB, such as timing advance information. Currently, the UE will release the positioning SRS configuration when cell reselection occurs. However, since the positioning SRS configuration also includes parameters that can be valid for a larger part (multiple cells) of the network, at least parts of the SRS configuration can be pre-configured.

[0167] To enable pre-configuration of positioning SRS, the positioning SRS parameters can be divided into two parts. The first part (referred to as “part (a)”) is a set of parameters that are valid for multiple cells. The area where this set of parameters is valid can be indicated by a list of cell IDs. This list of cell IDs can be considered as an “area ID” where the set of positioning SRS parameters are applicable or valid. The second part (referred to as “part (b)”) is a set of location / cell specific parameters. Part (a) for SRS for positioning configuration can be pre-configured, while part (b) will be provided in the SRS activation message.

[0168] Figure 8 is a diagram 800 illustrating a pre-configured positioning SRS structure according to aspects of the present disclosure. As shown, each pre-configured positioning SRS includes an identifier. Figure 8

[0169] The positioning SRS configuration for RRC inactive state currently includes the following parameters as specified in 3GPP TS 38.331, which is publicly available and incorporated herein in its entirety by reference. The “SRS-PosResourceSet” includes the “srs-PosResourceSetId,” “srs-PosResourceIdList,” “resourceType,” “alpha,” “p0,” and “pathlossReferenceRS-Pos” parameters. The “srs-PosResourceSetId” parameter indicates the ID of this resource set. It is unique in the context of the BWP where the positioning SRS is defined. The “srs-PosResourceIdList” parameter indicates the IDs of the SRS for positioning resources used in this “SRS-PosResourceSet.” The “resourceType” parameter defines the time domain behavior of the SRS resource configuration (e.g., periodic, semi-persistent, aperiodic). The “alpha” parameter indicates the value of the positioning SRS power control, which defines the fractional path loss compensation. The UE multiplies the alpha value with the path loss estimate. For full path loss compensation, alpha is equal to 1. The “p0” parameter indicates the value of the positioning SRS power control, which can be described as the “expected received power” at the TRP. That is, the SRS used for positioning transmit power determination is based on p0 + alpha x PL, where PL is the path loss estimate. The “pathlossReferenceRS-Pos” parameter defines the reference DL signal to be used for path loss estimation. The downlink reference signal can be an SSB or a DL-PRS from the serving TRP or a neighboring TRP.

[0170] ​The “SRS-PosResource” includes the “srs-PosResourceId,” “transmissionComb,” “resourceMapping,” “freqDomainShift,” “freqHopping,” “groupOrSequenceHopping,” “resourceType,” “sequenceId,” and “spatialRelationInfoPos” parameters. The “srs-PosResourceId” parameter indicates the SRS for positioning identity that defines a specific positioning SRS resource. The “transmissionComb” parameter defines the comb size N (e.g., N = 2, 4, or 8) of the positioning SRS, the comb offset (0...N-1) of the first symbol of the positioning SRS resource, and the cyclic shift used to generate the reference sequence. The “resourceMapping” (which includes “startPosition” and “nrofSymbols”) defines the first OFDM symbol position (e.g., 0, 1, 2,..., 13) of the positioning SRS resource in a slot and the number of symbols (e.g., 1, 2, 4, 8, or 12) of the positioning SRS resource. The “freqDomainShift” parameter defines the frequency domain location of the positioning SRS resource. The “freqHopping” parameter (or “c-SRS”) defines the bandwidth of the positioning SRS resource. The “groupOrSequenceHopping” parameter defines whether to use group hopping or sequence hopping. The hopping pattern is used to randomize the reuse of sequences in the system. The “resourceType” parameter defines the positioning SRS resource type (periodic, semi-persistent, aperiodic) and the periodicity of the semi-persistent and periodic positioning SRS. The “sequenceId” parameter defines the sequence ID used to initialize the pseudo-random group and sequence hopping. The “spatialRelationInfoPos” parameter defines the spatial relation between the reference signal and the target SRS. The reference signal can be an SSB, a CSI-RS, a DL-PRS, or an SRS.

[0171] Additional parameters include BWP information that defines the BWP configuration for the SRS used for positioning, including the frequency domain location and the bandwidth of the bandwidth part, the subcarrier spacing, and the cyclic prefix. The “inactivePosSRS-TimeAlignmentTimer” parameter indicates the timer value for the SRS used for positioning transmission. The “inactivePosSRS-RSRP-changeThreshold” parameter indicates the RSRP threshold for the increase / decrease of the RSRP for the time alignment verification.

[0172] The possible set of part (a) parameters that can be valid for multiple cells can include: “SRS-PosResourceSet”, “srs-PosResourceSetld”, “srs-PosResourceList”, “resourceType”, “SRS-PosResource”, “srs-PosResourceld”, “transmissionComb”, “resourceMapping” (“startPosition”, “nrofSymbols”), “freqDomainShift”, “freqHopping” (“c-SRS”), “groupOrSequenceHopping”, “resourceType”, and “sequenceId”. The possible set of part (b) parameters that are valid for a single (serving / receiving) cell can include: “alpha”, “p0”, “pathlossReferenceRS-Pos”, “spatialRelationlnfoPos”, BWP information, time alignment timer (e.g., timing advance timer), and RSRP change threshold. However, the implementation / deployment is free to divide the SRS parameters for positioning into the two sets (part (a) and part (b)) as needed. In special cases, all parameters can be eligible for “part (a)” SRS, e.g., when no pathloss reference or spatial relation, etc., is needed.

[0173] The pre-configuration would include the part (a) parameter set. The remaining parameters (part (b)) would be provided during the SRS activation procedure. Figure 7A and Figure 7B The illustrated procedure can then be modified as shown in Figure 9A and Figure 9B

[0174] Figure 9A and Figure 9B An example deferred MT LR procedure for downlink and uplink based positioning methods (e.g., multi-RTT) with positioning SRS pre-configuration is illustrated in accordance with aspects of the present disclosure. At stage 1, stage 1-21 of the deferred 5GC-MT-LR procedure for periodic or triggered location event specified in 3GPP TS 23.273, clause 6.3.1 is performed. Stages la, lb, and lc can be performed during the deferred MT-LR configuration phase of the deferred 5GC-MT-LR procedure for periodic or triggered location event (e.g., during stage 15 of the deferred 5GC-MT-LR procedure for periodic or triggered location event specified in 3GPP TS 23.273, clause 6.3.1). ​

[0175] At stage la, the LMF 270 transmits an NRPPa Position Information Request message including a request for preconfigured positioning SRSs to the serving gNB 222. The request can include one or more "Requested SRS Transmission Characteristics" IEs, each defining a desired positioning SRS configuration. The LMF 270 can include a path loss reference, spatial relation, and SSB information for each gNB in the area. This "assistance information" can be used by the serving / receiving gNB 222 to compile the part (b) parameters valid for the current UE position at a later time. For example, for each considered cell ID, the assistance information can include a list of neighboring cells with SSB or DL-PRS information that can be used as a path loss reference or spatial relation for positioning SRSs.

[0176] At stage lb, the serving gNB 222 determines one or more positioning SRS configurations and provides these configurations to the target device (UE 204) for the target device to transmit positioning SRSs at a later time (i.e., the target device does not transmit any positioning SRSs while preconfigured). Each positioning SRS configuration has an associated identifier as Figure 8 illustrated. Each positioning SRS can have a validity time and / or a validity area. The "validity area" can be defined by a list of cell IDs defining where the SRS configuration is applicable / valid.

[0177] At stage lc, the serving gNB 222 provides the set of preconfigured positioning SRSs to the LMF 270 (e.g., one or more "SRS Configuration" IEs, where each positioning SRS has an associated ID as Figure 8 illustrated).

[0178] At stage 3, after detecting the event (or earlier), the UE 204 transmits an SRS activation request message along with an RRC resume request to the receiving gNB 222. The SRS activation request message can include the identifiers of the desired preconfigured SRS configurations (e.g., in priority order) to activate.

[0179] At stage 4, the receiving gNB 222 identifies the last serving gNB 222 using the Inactive Radio Network Temporary Identifier (I-RNTI) and retrieves the UE context (including preconfigured positioning SRS information) by means of the Xn-AP Retrieve UE Context procedure. The receiving gNB 222 determines the positioning SRS configuration based on the pre-configuration during stage 1. The receiving gNB 222 can determine part (b) parameters such as pathloss reference information (e.g., “alpha”, “p0”, “pathlossReferenceRS-Pos”) or spatial relation information (e.g., “spatialRelationlnfoPos”) of the positioning SRS valid for the receiving gNB 222. The receiving gNB 222 can also determine the time alignment timer and RSRP change threshold (e.g., “inactivePosSRS-TimeAlignmentTimer”, “inactivePosSRS-RSRP-changeThreshold”). The receiving gNB 222 can use the assistance information received from the LMF 270 at stage la to determine the above set of SRS parameters.

[0180] At stage 5, the receiving gNB 222 can then transmit to the UE 204 an SRS activation message including the ID of the preconfigured SRS to be activated, and part (b) SRS information (e.g., pathloss reference, spatial relation, timing advance (TA) timer, and RSRP change threshold). The SRS activation message can be an RRC message or a MAC-CE or DCI. The UE 204 then starts transmitting the positioning SRS according to the activated configuration.

[0181] At stage 6, the receiving gNB 222 transmits to the LMF 270 an NRPPa Positioning Information Update message including the ID of the activated positioning SRS.

[0182] At stage 7, the LMF 270 transmits to the gNB / TRP group an NRPPa Measurement Request message including the positioning SRS measurement configuration (i.e., based on the ID received at stage 6).

[0183] At stage 8, the receiving gNB 222 transmits to the UE 204 an RRC Release message to release the UE 204 to the RRC Inactive state. If stage 5 does not occur, the RRC Release message includes the SRS activation message. The various network entities then perform stages 11-17 illustrated in Figure 7B

[0184] with Figure 7A and Figure 7B ​The processes illustrated in the middle would not require the signaling for SRS configuration (stages 5, 6, 7, and 9), thus reducing the latency of SRS configuration, and thus reducing power consumption (i.e., reducing the UE “wake-up time” between stage 3 and stage 10 in Figure 7A ).

[0185] The preconfigured SRS assistance data can consist of multiple preconfigured SRS configurations, where each preconfigured SRS configuration is applicable to a different SRS validity area within the network. Each preconfigured SRS configuration can be associated with an area identifier (ID). The area ID includes a list of cells on which the UE can camp (in RRC inactive state) or to which the UE can connect (in RRC connected state). The applicable area ID at the UE location is selected based on the cell on which / to which the UE camps / connects. The preconfigured SRS configuration is valid / selected if the UE camps on or connects to one of the cells indicated in the cell list in the area ID.

[0186] Figure 10 is a diagram 1000 illustrating an example UE mobility scenario through multiple SRS validity areas, in accordance with aspects of the present disclosure. In the example of Figure 10 , there are six area IDs (labeled “AreaID1” through “AreaID6”), each including multiple cells (labeled “PCI1” through “PCI16”). Note that while Figure 10 a single cell / PCI per physical cell site is illustrated, this is for simplicity and as will be appreciated, a cell site can support multiple cells. Further, in the example of Figure 10 , certain cells can belong to more than one area ID. For example, PCI4 can belong to both AreaID1 and AreaID2. Similarly, PCI7 can belong to both AreaID3 and AreaID4.

[0187] For SRS configuration, referring to Figure 10 , the UE can be configured with a preconfigured SRS configuration for each of AreaID1 through AreaID6. Since the UE is currently in AreaID4, the preconfigured SRS configuration associated with AreaID4 is valid / selected if the UE camps on or connects to one of the cells (e.g., PCI3, PCI7, PCI11, PCI15) associated with areaID4.

[0188] To enable greater network control over the transmission of positioning SRS (or SRS for positioning) after cell reselection, an LPP “Area-ID-CellList” information element (IE) has been introduced for (pre-)configured positioning SRS. The “Area-ID-CellList” IE for positioning SRS will be UE-specific compared to DL-PRS assistance data validity. If the UE camps on a cell whose ID is included in the “Area-ID-CellList” IE, the UE will be permitted to continue (associated) positioning SRS transmission in the new cell after cell reselection. That is, if the UE is engaged in an uplink-based or downlink-and-uplink-based positioning procedure in which the UE transmits positioning SRS and hands over / re-attaches to a different cell, the UE can continue to transmit the same positioning SRS as long as that cell is included in the “Area-ID-CellList” IE.

[0189] Figure 11 An example RRC “SRS-PosRRC-Inactive” IE 1100 according to aspects of the present disclosure is illustrated. This IE configures the UE with one or more positioning SRS configurations to use while in the RRC Inactive state 430. Specifically, the “SRS-PosRRC-Inactive” IE provides a set of up to “maxPreConfig” positioning SRS configurations, where each configuration can be identified by the “srs-PosID” field. The “srs-ValidityArea” field provides a list of cell IDs in which the SRS configuration is valid. If the UE reselects to a cell included in the LPP “Area-ID-CellList” IE, the UE is permitted to continue SRS transmission during and after cell reselection. Note that the “Area-ID-CellList” IE can not necessarily coincide with the RNA, but can be a dedicated, UE-specific uplink positioning area.

[0190] The RRC “SRS-PosRRC-Inactive” IE avoids interruption of SRS transmission at cell reselection, which reduces the amount of SRS configuration signaling needed, reduces latency of the positioning session, and thus reduces power consumption at the target device.

[0191] A UE transmits SRS and other uplink transmissions according to its uplink timing. Simply put, uplink timing is the downlink reference timing plus an uplink timing advance (TA). The downlink reference timing (or simply “downlink timing”) is defined as the time of the (in time) first detected path of a corresponding downlink frame received from a reference cell (e.g., the UE’s serving cell or the cell on which the UE is camping). The uplink TA takes into account the round-trip propagation delay between the UE and the reference cell, with UEs closer to the cell having a shorter propagation delay and thus a smaller TA, and UEs further away from the cell having a longer propagation delay and thus a larger TA.

[0192] The uplink TA helps to ensure that uplink transmissions from all UEs are synchronized when received by a cell. When a UE is in an RRC connected state, its serving cell configures it with an uplink TA. However, in the case of moving from cell to cell while in an RRC inactive or idle state, the uplink TA can be different for the cell on which the UE is currently camping. This can become a problem in the case that the UE is configured to transmit SRS for positioning while in an RRC inactive state, as for example the transmission can not occur at the time expected by the network and / or can interfere with other uplink transmissions from other UEs.

[0193] In some cases, it is feasible to configure the UE in RRC inactive state with a TA timer that is specific to the positioning SRS validity area. For example, the TA timer can have a larger value when the UE is in RRC inactive state than when the UE is in RRC connected state. In addition, it is feasible to use an area-specific RSRP change threshold for TA verification.

[0194] There are different options, referred to herein as “uplink TA derivation rules” (or “TA derivation rules” or “derivation rules” or simply “rules”), for determining the uplink timing for transmitting SRS for positioning by a UE in RRC inactive state within a positioning SRS validity area. As a first option or rule, the UE can maintain the uplink TA obtained from the last serving cell within the validity area. In this case, as the UE moves, the uplink TA value should remain constant within the area. However, since the downlink timing can change, the uplink timing can also change, and this change can be abrupt if the UE suddenly changes the cell used for downlink timing determination.

[0195] As a second TA derivation rule, the UE can autonomously adjust the uplink TA. How the UE adjusts the TA can depend on the UE implementation or based on the TA from the last serving cell and the downlink time difference measurements from the SSBs of the last serving cell and the new camped cell. In this case, as the UE moves, the uplink timing should remain constant within the SRS validity area. However, since the downlink timing can change, the uplink TA value will also change such that the resulting sum (i.e., the uplink timing) remains the same.

[0196] As a third TA derivation rule, the UE can maintain multiple uplink TA values. In this case, the UE can perform a random access procedure (e.g., a random access channel (RACH) procedure) to a new cell and receive a TA value for the new cell. As the UE moves around, the UE should track the uplink TA value associated with each cell.

[0197] The present disclosure provides a variety of uplink TA solutions for the above scenarios. Specifically, the UE can support one or more different options for determining the uplink TA within the SRS validity area. As a first option, for example, for a first subset of cells in the SRS validity area, the UE can maintain the same uplink TA value, and for another subset of cells, the UE can maintain the same uplink timing. In this case, the SRS validity area can be divided into subsets, or sub-areas, of cells, and different rules (e.g., the same uplink TA value or the same uplink timing) can apply to different sub-areas within the same SRS validity area. That is, the TA derivation rule for each sub-area can be independent of the TA derivation rule for other sub-areas of the SRS validity area.

[0198] As a second option, for each SRS validity area, the UE is configured to apply one or the other uplink TA derivation rule. That is, there is a configuration in the area-specific SRS parameters that indicates which TA derivation rule (e.g., the same uplink TA value or the same uplink timing) should be applied. In this case, the SRS validity area is characterized by the way in which the uplink TA is maintained.

[0199] As a third option, depending on whether the UE is configured to perform SDT or non-area-specific SRS transmission, the UE can select the first TA derivation rule (constant uplink TA), the second TA derivation rule (autonomous uplink TA adjustment), or the third TA derivation rule (multiple uplink TAs).

[0200] As a fourth option, the UE can be configured to keep the same uplink TA value as long as the change in downlink reference timing compared to the initial downlink reference timing value does not exceed a configured threshold. In this case, the UE is permitted to adjust the uplink TA value to ensure that the change in downlink reference timing is less than the threshold.

[0201] This fourth option has different sub-options. Each sub-option indicates the uplink timing for the UE in RRC inactive state to transmit SRS for positioning within the SRS positioning validity area. The first sub-option combines the first TA derivation rule and the second TA derivation rule described above (i.e., constant uplink TA and autonomous uplink TA adjustment). In this case, the UE maintains the TA obtained from the last serving cell within the SRS validity area as long as the change in downlink reference timing does not exceed a threshold (e.g., X nanoseconds (ns)), otherwise the UE can autonomously adjust the uplink TA.

[0202] The second sub-option combines the first TA derivation rule and the third TA derivation rule described above (i.e., constant uplink TA and multiple TA values). In this case, the UE maintains the uplink TA obtained from the last serving cell within the SRS validity area as long as the change in downlink reference timing does not exceed a threshold. Otherwise, the UE can perform a random access procedure to obtain a new uplink TA value.

[0203] The third sub-option also combines the first TA derivation rule and the second TA derivation rule described above (i.e., constant uplink TA and autonomous uplink TA adjustment), but in reverse order. In this case, the UE can autonomously adjust the TA obtained from the last serving cell within the SRS validity area such that the change in uplink timing does not exceed a threshold (e.g., Y ns).

[0204] The fourth sub-option combines the first TA derivation rule, the second TA derivation rule, and the third TA derivation rule described above. In this case, the UE can autonomously adjust the TA obtained from the last serving cell within the SRS validity area. In this case, the change in uplink timing should not exceed a threshold (e.g., Y ns), otherwise the UE can perform a random access procedure to obtain a new TA value.

[0205] As a fourth option, the TA derivation rule to apply can be determined based on whether a change in the UE’s uplink timing would exceed a threshold. Here, the UE can measure the new downlink reference timing, and if using that new downlink reference timing would result in a change in uplink timing that exceeds a threshold, the UE selects the TA derivation rule accordingly. For example, if the downlink reference time changes by 500 ns, and the UE attempts to change the uplink TA by -300 ns (e.g., the UE can not be able to compensate more), the change in uplink timing would be 200 ns (i.e., 500 - 300 = 200 ns), which can exceed the allowed threshold.

[0206] The present disclosure also provides techniques for handling uplink timing and / or uplink TA values when transmitting new SRS for positioning and / or other physical layer channels. In RRC inactive state, the UE can have to transmit one or more of the following signals and channels: (1) SRS for positioning without area-specific configuration (like traditional positioning SRS); (2) SDT uplink channel (e.g., PUSCH); and / or (3) area-specific SRS for positioning. Special handling can be needed if the area-specific SRS for positioning is handled differently in terms of uplink timing and TA validity.

[0207] As a first option, transmitting SRS for positioning in a new cell (i.e., a new cell that the UE has camped on) should follow the first TA derivation rule or the second TA derivation rule (i.e., constant uplink TA and autonomous uplink TA adjustment) described above. This means that transmitting SRS for positioning in the new cell will use the TA value from the previous serving cell. However, any other uplink channel will follow the uplink timing / TA value of the new cell that the UE camps on. Thus, two TA values can be needed, one for area-specific SRS for positioning and one for non-area-specific SRS or other uplink channels.

[0208] As a first sub-option, if the UE does not support two TA values in a cell (i.e., does not support transmitting according to two different TA values in the same cell), transmitting area-specific SRS for positioning can follow the TA of other channels. In other words, if the UE is configured with both area-specific SRS and any other legacy transmission (e.g., SDT, non-area-specific SRS, etc.), the new TA derivation rule does not apply. Alternatively, as long as area-specific SRS is configured, all uplink channels will have to follow the new TA derivation rule described above.

[0209] As a second sub-option, in case the UE supports maintaining two TA values in a cell (which can be reported to the network as UE capability), then for each time slot, only a single TA can be used. In this case, it can not be allowed (by the network) to configure a zone-specific SRS in the same time slot as other channels, or a priority rule can be defined. For example, the priority rule can be to drop the zone-specific SRS in case it occurs in the same time slot as other channels, or to update the TA used in that time slot so that a single TA is adopted (referred to as "TA override"). Alternatively, multiple TA values can be allowed within the same time slot, but in this case, there should be a time-domain gap between the two uplink channels with different TA values. If the gap is not present, or is not sufficient to allow the two TA values, one of the two channels is dropped.

[0210] As a second option, the UE can follow the third TA derivation rule described above (i.e., multiple TA values). In this case, when the UE moves to a new cell, it performs a random access procedure to obtain a new uplink TA value. This value should then be applied to all channels scheduled to be transmitted in a time slot (e.g., zone-specific SRS, non-zone-specific SRS, and other uplink channels).

[0211] Figure 12 An example method 1200 of wireless communication in accordance with aspects of the present disclosure is illustrated. In an aspect, method 1200 can be performed by a UE (e.g., any of the UEs described herein).

[0212] At 1210, the UE receives one or more SRS configurations associated with one or more SRS validity zones, where each SRS validity zone of the one or more SRS validity zones includes one or more cells. In an aspect, operation 1210 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, memory 340, and / or positioning component 342, any or all of which can be considered means for performing this operation.

[0213] At 1220, while operating in an RRC inactive state and while camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, the UE transmits one or more first zone-specific SRS based on the one or more SRS configurations and an uplink timing of the UE, where the uplink timing of the UE is equal to a sum of a downlink reference timing and a first value of an uplink TA of the UE. In an aspect, operation 1220 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, memory 340, and / or positioning component 342, any or all of which can be considered means for performing this operation.

[0214] In an aspect, the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining the value of the uplink TA from a latest serving cell within a SRS validity zone associated with the UE; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust the value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell based on a random access procedure with the cell on which the UE is camped.

[0215] In an aspect, the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform an SDT, a non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0216] Figure 13 An example method 1300 of wireless communication in accordance with aspects of the present disclosure is illustrated. In an aspect, method 1300 can be performed by a UE (e.g., any of the UEs described herein).

[0217] At 1310, the UE transmits one or more zone-specific SRS while operating in a RRC non-connected state and while camped on a first cell of a first SRS validity zone, where the one or more zone-specific SRS are associated with a first uplink TA. In an aspect, operation 1310 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, memory 340, and / or positioning component 342, any or all of which can be considered means for performing this operation.

[0218] At 1320, the UE transmits one or more physical layer uplink channels while operating in the RRC non-connected state and while camped on the first cell of the first SRS validity zone, where the one or more physical layer uplink channels are associated with a second uplink TA. In an aspect, operation 1320 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, memory 340, and / or positioning component 342, any or all of which can be considered means for performing this operation.

[0219] As will be appreciated, a technical advantage of methods 1200 and 1300 is determining an appropriate uplink TA for transmitting a positioning SRS in a positioning SRS validity zone.

[0220] In the detailed description above, various features are grouped together in examples. This manner of disclosure should not be understood as an intention that the example clauses are to be taken exclusively, and that features are to be understood only in the context of the example clause specifying the feature. Rather, various aspects of the disclosure can include fewer than all features of any single disclosed example clause. Therefore, the following clauses should be construed in this manner: as the description is to be read to include in the description not only single examples employing each and every feature recited in that clause, but also is to be read to include in the description each and every combination of the features recited in that clause. Although each dependent clause can refer to a particular combination of features of one of the example clauses, aspects of that dependent clause are not limited to the particular combination of features of that one clause. It is to be understood that other example clauses can include a combination of features from any of the dependent clauses or independent clauses. The various aspects disclosed herein expressly contemplate these combinations, unless it is explicitly stated or is readily apparent from the explicit statements that a particular combination is not intended (e.g., contradictory aspects, such as defining an element as both an electrical insulator and an electrical conductor). Moreover, it is also contemplated that aspects of a clause can be included in any other independent clause, even if the clause does not directly depend on the independent clause.

[0221] The various embodiments are described in the following numbered clauses:

[0222] Clause 1. A method of wireless communication performed by a user equipment (UE), the method comprising: receiving one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and transmitting one or more first zone-specific SRS based on the one or more SRS configurations and an uplink timing of the UE while operating in a radio resource control (RRC) non-connected state and while camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone in which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure with the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0223] Clause 2. The method of clause 1, wherein: the uplink TA derivation rule applies to all cells in the first sub-zone of the plurality of sub-zones of the first SRS validity zone, and a different uplink TA derivation rule applies to all cells in a different sub-zone of the plurality of sub-zones of the first SRS validity zone.

[0224] Clause 3. The method of any one of clauses 1-2, wherein: the uplink TA derivation rule is indicated in the one or more SRS configurations, and the one or more SRS configurations indicate different uplink TA derivation rules for the one or more SRS validity zones.

[0225] Clause 4. The method of any of clauses 1-3, wherein the uplink TA derivation rule is determined based on whether the UE is configured to perform SDT, non-area specific SRS transmission, or both.

[0226] Clause 5. The method of any of clauses 1-4, wherein the uplink TA derivation rule is determined based on whether a change in the downlink reference timing has exceeded the first threshold.

[0227] Clause 6. The method of clause 5, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the second uplink TA derivation rule.

[0228] Clause 7. The method of any of clauses 5-6, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0229] Clause 8. The method of any of clauses 5-7, wherein the uplink TA derivation rule comprises the second uplink TA derivation rule to prevent a change in the uplink timing of the UE from exceeding the second threshold.

[0230] Clause 9. The method of clause 8, wherein based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0231] Clause 10. The method of any of clauses 8-9, wherein the second uplink TA derivation rule is applied by adjusting the uplink TA such that the uplink timing of the UE remains constant within the second threshold.

[0232] Clause 11. The method of any of clauses 5-10, wherein the downlink reference timing is for a latest serving cell within the first SRS validity area.

[0233] Clause 12. The method of any of clauses 1-11, wherein an uplink transmission time of the one or more first area-specific SRS is the downlink reference timing plus the first value of the uplink TA.

[0234] Clause 13. The method of any of clauses 1-12, wherein the one or more first region-specific SRS comprise positioning SRS.

[0235] Clause 14. The method of any of clauses 1-13, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0236] Clause 15. A method of wireless communication performed by a user equipment (UE), comprising: transmitting one or more region-specific SRS when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first sounding reference signal (SRS) validity region, wherein the one or more region-specific SRS are associated with a first uplink timing advance (TA); and transmitting one or more physical layer uplink channels when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity region, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0237] Clause 16. The method of clause 15, wherein: the first uplink TA is for a latest serving cell within the first SRS validity region, and the second uplink TA is for the first cell.

[0238] Clause 17. The method of clause 16, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more region-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0239] Clause 18. The method of clause 16, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more region-specific SRS and the one or more physical layer uplink channels are transmitted based on the first uplink TA, and the second uplink TA is the same as the first uplink TA.

[0240] Clause 19. The method of any of clauses 16 to 18, wherein: a value of the first uplink TA is determined based on an uplink TA derivation rule, and the uplink TA derivation rule comprises: (1) a first uplink TA derivation rule comprising obtaining the value of the first uplink TA from the latest serving cell within the first SRS validity zone; or (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the first uplink TA.

[0241] Clause 20. The method of any of clauses 16 and 19, wherein: the UE supports at least two uplink TAs within a cell, and the one or more zone-specific SRSs and the one or more physical layer uplink channels are scheduled to be transmitted in a same slot.

[0242] Clause 21. The method of clause 20, further comprising: based on the one or more zone-specific SRSs and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot, preventing the one or more zone-specific SRSs from being transmitted in the same slot.

[0243] Clause 22. The method of any of clauses 20 to 21, wherein: based on the one or more zone-specific SRSs and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot, both the one or more zone-specific SRSs and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0244] Clause 23. The method of any of clauses 20 to 22, wherein: the UE supports the one or more zone-specific SRSs and the one or more physical layer uplink channels being transmitted in the same slot based on different uplink TAs, and a time gap is scheduled between the one or more zone-specific SRSs and the one or more physical layer uplink channels in the same slot to permit the one or more zone-specific SRSs and the one or more physical layer uplink channels to be transmitted in the same slot.

[0245] Clause 24. The method of any of clauses 20 to 22, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, there is no time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot, the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0246] Clause 25. The method of any of clauses 20 to 24, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, and the one or more zone-specific SRS or the one or more physical layer uplink channels are not transmitted in the same slot based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot without a time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels.

[0247] Clause 26. The method of any of clauses 16 to 25, wherein: the one or more zone-specific SRS are transmitted in a first slot based on the first uplink TA, and the one or more physical layer uplink channels are transmitted in a second slot based on the second uplink TA.

[0248] Clause 27. The method of any of clauses 15 to 26, wherein: both the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0249] Clause 28. The method of any of clauses 15 to 27, wherein the second uplink TA is obtained based on a random access procedure with the first cell.

[0250] Clause 29. The method of any of clauses 15 to 28, wherein the one or more physical layer uplink channels comprise: one or more non-zone-specific SRS, one or more short data transmissions (SDTs), or any combination thereof.

[0251] Clause 30. The method of any of clauses 15 to 29, wherein the one or more region-specific SRS comprise positioning SRS.

[0252] Clause 31. The method of any of clauses 15 to 30, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0253] Clause 32. A user equipment (UE), comprising: one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: receive, via the one or more transceivers, one or more sounding reference signal (SRS) configurations associated with one or more SRS validity regions, wherein each SRS validity region of the one or more SRS validity regions comprises one or more cells; and while operating in a radio resource control (RRC) non-connected state and while camped on a first cell of a first SRS validity region of the one or more SRS validity regions, transmit, via the one or more transceivers, one or more first region-specific SRS based on the one or more SRS configurations and an uplink timing of the UE, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity region in which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure with the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-region of the first SRS validity region containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-region-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0254] Clause 33. The UE of clause 32, wherein: the uplink TA derivation rule applies to all cells in the first sub-region of the plurality of sub-regions of the first SRS validity zone, and a different uplink TA derivation rule applies to all cells in a different sub-region of the plurality of sub-regions of the first SRS validity zone.

[0255] Clause 34. The UE of any of clauses 32 to 33, wherein: the uplink TA derivation rule is indicated in the one or more SRS configurations, and the one or more SRS configurations indicate different uplink TA derivation rules for the one or more SRS validity zones.

[0256] Clause 35. The UE of any of clauses 32 to 34, wherein the uplink TA derivation rule is determined based on whether the UE is configured to perform an SDT, a non-zone-specific SRS transmission, or both.

[0257] Clause 36. The UE of any of clauses 32 to 35, wherein the uplink TA derivation rule is determined based on whether a change in the downlink reference timing has exceeded the first threshold.

[0258] Clause 37. The UE of clause 36, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the second uplink TA derivation rule.

[0259] Clause 38. The UE of any of clauses 36 to 37, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0260] Clause 39. The UE of any of clauses 36 to 38, wherein the uplink TA derivation rule comprises the second uplink TA derivation rule to prevent a change in the uplink timing of the UE from exceeding the second threshold.

[0261] Clause 40. The UE of clause 39, wherein based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0262] Clause 41. The UE of any of clauses 39 to 40, wherein the second uplink TA derivation rule is applied by adjusting the uplink TA such that the uplink timing of the UE remains constant within the second threshold.

[0263] Clause 42. The UE of any of clauses 36 to 41, wherein the downlink reference timing is for a latest serving cell within the first SRS validity zone.

[0264] Clause 43. The UE of any of clauses 32 to 42, wherein an uplink transmission time of the one or more first zone-specific SRSs is the downlink reference timing plus the first value of the uplink TA.

[0265] Clause 44. The UE of any of clauses 32 to 43, wherein the one or more first zone-specific SRSs comprise positioning SRSs.

[0266] Clause 45. The UE of any of clauses 32 to 44, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0267] Clause 46. A user equipment (UE), comprising: one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: transmit, via the one or more transceivers, one or more zone-specific sounding reference signals (SRSs) when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone, wherein the one or more zone-specific SRSs are associated with a first uplink timing advance (TA); and transmit, via the one or more transceivers, one or more physical layer uplink channels when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0268] Clause 47. The UE of clause 46, wherein: the first uplink TA is for a latest serving cell within the first SRS validity zone, and the second uplink TA is for the first cell.

[0269] Clause 48. The UE of clause 47, wherein: the UE does not support multiple uplink TAs within a cell, the one or more zone-specific SRS and the one or more physical layer uplink channels are both transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0270] Clause 49. The UE of clause 47, wherein: the UE does not support multiple uplink TAs within a cell, the one or more zone-specific SRS and the one or more physical layer uplink channels are both transmitted based on the first uplink TA, and the second uplink TA is the same as the first uplink TA.

[0271] Clause 50. The UE of any of clauses 47 to 49, wherein: a value of the first uplink TA is determined based on an uplink TA derivation rule, and the uplink TA derivation rule comprises: (1) a first uplink TA derivation rule comprising obtaining the value of the first uplink TA from the latest serving cell within the first SRS validity zone; or (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the first uplink TA.

[0272] Clause 51. The UE of any of clauses 47 and 50, wherein: the UE supports at least two uplink TAs within a cell, and the one or more zone-specific SRS and the one or more physical layer uplink channels are scheduled to be transmitted in a same slot.

[0273] Clause 52. The UE of clause 51, wherein the one or more processors are further configured to: prevent transmission of the one or more zone-specific SRS in the same slot based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot.

[0274] Clause 53. The UE of any of clauses 51 to 52, wherein: based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot, both the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0275] Clause 54. The UE of any of clauses 51-53, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, and a time gap is scheduled between the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot to permit transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot.

[0276] Clause 55. The UE of any of clauses 51-53, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, there is no time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot, the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0277] Clause 56. The UE of any of clauses 51-55, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, and there is no time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot, the one or more zone-specific SRS or the one or more physical layer uplink channels are not transmitted in the same slot.

[0278] Clause 57. The UE of any of clauses 47-56, wherein: the one or more zone-specific SRS are transmitted in a first slot based on the first uplink TA, and the one or more physical layer uplink channels are transmitted in a second slot based on the second uplink TA.

[0279] Clause 58. The UE of any of clauses 46-57, wherein: both the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0280] Clause 59. The UE of any of clauses 46 to 58, wherein the second uplink TA is obtained based on a random access procedure with the first cell.

[0281] Clause 60. The UE of any of clauses 46 to 59, wherein the one or more physical layer uplink channels comprise one or more non-area specific SRS, one or more short data transmissions (SDTs), or any combination thereof.

[0282] Clause 61. The UE of any of clauses 46 to 60, wherein the one or more area specific SRS comprise positioning SRS.

[0283] Clause 62. The UE of any of clauses 46 to 61, wherein the RRC non-connected state comprises an RRC inactive state or an RRC idle state.

[0284] Clause 63. A user equipment (UE), the user equipment (UE) comprising: means for receiving one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and means for transmitting one or more first zone-specific SRS based on the one or more SRS configurations and an uplink timing of the UE while operating in a radio resource control (RRC) idle state and while camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone in which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure with the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0285] Clause 64. The UE of clause 63, wherein: the uplink TA derivation rule applies to all cells in the first sub-zone of the plurality of sub-zones of the first SRS validity zone, and a different uplink TA derivation rule applies to all cells in a different sub-zone of the plurality of sub-zones of the first SRS validity zone.

[0286] Clause 65. The UE of any of clauses 63 to 64, wherein: the uplink TA derivation rule is indicated in the one or more SRS configurations, and the one or more SRS configurations indicate different uplink TA derivation rules for the one or more SRS validity zones.

[0287] Clause 66. The UE of any of clauses 63 to 65, wherein the uplink TA derivation rule is determined based on whether the UE is configured to perform SDT, non-area specific SRS transmissions, or both.

[0288] Clause 67. The UE of any of clauses 63 to 66, wherein the uplink TA derivation rule is determined based on whether a change in the downlink reference timing has exceeded the first threshold value.

[0289] Clause 68. The UE of clause 67, wherein: based on the change in the downlink reference timing being less than the first threshold value, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold value, the uplink TA derivation rule comprises the second uplink TA derivation rule.

[0290] Clause 69. The UE of any of clauses 67 to 68, wherein: based on the change in the downlink reference timing being less than the first threshold value, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold value, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0291] Clause 70. The UE of any of clauses 67 to 69, wherein the uplink TA derivation rule comprises the second uplink TA derivation rule to prevent a change in the uplink timing of the UE from exceeding the second threshold value.

[0292] Clause 71. The UE of clause 70, wherein based on the change in the downlink reference timing exceeding the first threshold value, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0293] Clause 72. The UE of any of clauses 70 to 71, wherein the second uplink TA derivation rule is applied by adjusting the uplink TA such that the uplink timing of the UE remains constant within the second threshold value.

[0294] Clause 73. The UE of any of clauses 67 to 72, wherein the downlink reference timing is for a latest serving cell within the first SRS validity area.

[0295] Clause 74. The UE of any of clauses 63 to 73, wherein an uplink transmission time of the one or more first area-specific SRS is the downlink reference timing plus the first value of the uplink TA.

[0296] Clause 75. The UE of any of clauses 63 to 74, wherein the one or more first region-specific SRS comprise positioning SRS.

[0297] Clause 76. The UE of any of clauses 63 to 75, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0298] Clause 77. A user equipment (UE), comprising: means for transmitting one or more region-specific SRS when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity region, wherein the one or more region-specific SRS are associated with a first uplink timing advance (TA); and means for transmitting one or more physical layer uplink channels when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity region, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0299] Clause 78. The UE of clause 77, wherein: the first uplink TA is for a latest serving cell within the first SRS validity region, and the second uplink TA is for the first cell.

[0300] Clause 79. The UE of clause 78, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more region-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0301] Clause 80. The UE of clause 78, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more region-specific SRS and the one or more physical layer uplink channels are transmitted based on the first uplink TA, and the second uplink TA is the same as the first uplink TA.

[0302] Clause 81. The UE of any of clauses 78 to 80, wherein: a value of the first uplink TA is determined based on an uplink TA derivation rule, and the uplink TA derivation rule comprises: (1) a first uplink TA derivation rule comprising obtaining the value of the first uplink TA from the latest serving cell within the first SRS validity zone; or (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the first uplink TA.

[0303] Clause 82. The UE of any of clauses 78 and 81, wherein: the UE supports at least two uplink TAs within a cell, and the one or more zone-specific SRSs and the one or more physical layer uplink channels are scheduled to be transmitted in a same slot.

[0304] Clause 83. The UE of clause 82, further comprising: means for preventing transmission of the one or more zone-specific SRSs in the same slot based on the one or more zone-specific SRSs and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot.

[0305] Clause 84. The UE of any of clauses 82 to 83, wherein: based on the one or more zone-specific SRSs and the one or more physical layer uplink channels being scheduled to be transmitted in the same slot, both the one or more zone-specific SRSs and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0306] Clause 85. The UE of any of clauses 82 to 84, wherein: the UE supports transmission of the one or more zone-specific SRSs and the one or more physical layer uplink channels in the same slot based on different uplink TAs, and a time gap is scheduled between the one or more zone-specific SRSs and the one or more physical layer uplink channels in the same slot to permit transmission of the one or more zone-specific SRSs and the one or more physical layer uplink channels in the same slot.

[0307] Clause 86. The UE of any of clauses 82 to 84, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot without a time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels, the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted in the same slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0308] Clause 87. The UE of any of clauses 82 to 86, wherein: the UE supports transmitting the one or more zone-specific SRS and the one or more physical layer uplink channels in the same slot based on different uplink TAs, and based on the one or more zone-specific SRS and the one or more physical layer uplink channels being scheduled in the same slot without a time gap between the one or more zone-specific SRS and the one or more physical layer uplink channels, the one or more zone-specific SRS or the one or more physical layer uplink channels are not transmitted in the same slot.

[0309] Clause 88. The UE of any of clauses 78 to 87, wherein: the one or more zone-specific SRS are transmitted in a first slot based on the first uplink TA, and the one or more physical layer uplink channels are transmitted in a second slot based on the second uplink TA.

[0310] Clause 89. The UE of any of clauses 77 to 88, wherein: both the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0311] Clause 90. The UE of any of clauses 77 to 89, wherein the second uplink TA is obtained based on a random access procedure with the first cell.

[0312] Clause 91. The UE of any of clauses 77 to 90, wherein the one or more physical layer uplink channels comprise: one or more non-zone-specific SRS, one or more short data transmissions (SDTs), or any combination thereof.

[0313] Clause 92. The UE of any of clauses 77 to 91, wherein the one or more area-specific SRS comprise positioning SRS.

[0314] Clause 93. The UE of any of clauses 77 to 92, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0315] Clause 94. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: receive one or more sounding reference signal (SRS) configurations associated with one or more SRS validity areas, wherein each SRS validity area of the one or more SRS validity areas comprises one or more cells; and while operating in a radio resource control (RRC) non-connected state and while camped on a first cell of a first SRS validity area of the one or more SRS validity areas, transmit one or more first area-specific SRS based on the one or more SRS configurations and an uplink timing of the UE, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity area with which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell with which the UE is camped based on a random access procedure of the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-area of a plurality of sub-areas of the first SRS validity area that contains the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-area-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

[0316] Clause 95. The non-transitory computer-readable medium of Clause 94, wherein: the uplink TA derivation rule applies to all cells in the first sub-region of the plurality of sub-regions of the first SRS validity zone, and a different uplink TA derivation rule applies to all cells in a different sub-region of the plurality of sub-regions of the first SRS validity zone.

[0317] Clause 96. The non-transitory computer-readable medium of any one of Clauses 94-95, wherein: the uplink TA derivation rule is indicated in the one or more SRS configurations, and the one or more SRS configurations indicate different uplink TA derivation rules for the one or more SRS validity zones.

[0318] Clause 97. The non-transitory computer-readable medium of any one of Clauses 94-96, wherein the uplink TA derivation rule is determined based on whether the UE is configured to perform an SDT, a non-zone-specific SRS transmission, or both.

[0319] Clause 98. The non-transitory computer-readable medium of any one of Clauses 94-97, wherein the uplink TA derivation rule is determined based on whether a change in the downlink reference timing has exceeded the first threshold.

[0320] Clause 99. The non-transitory computer-readable medium of Clause 98, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the second uplink TA derivation rule.

[0321] Clause 100. The non-transitory computer-readable medium of any one of Clauses 98-99, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0322] Clause 101. The non-transitory computer-readable medium of any one of Clauses 98-100, wherein the uplink TA derivation rule comprises the second uplink TA derivation rule to prevent a change in the uplink timing of the UE from exceeding the second threshold.

[0323] Clause 102. The non-transitory computer-readable medium of clause 101, wherein based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

[0324] Clause 103. The non-transitory computer-readable medium of any of clauses 101 to 102, wherein the second uplink TA derivation rule is applied by adjusting the uplink TA such that the uplink timing of the UE remains constant within the second threshold.

[0325] Clause 104. The non-transitory computer-readable medium of any of clauses 98 to 103, wherein the downlink reference timing is for a latest serving cell within the first SRS validity zone.

[0326] Clause 105. The non-transitory computer-readable medium of any of clauses 94 to 104, wherein an uplink transmission time of the one or more first zone-specific SRSs is the downlink reference timing plus the first value of the uplink TA.

[0327] Clause 106. The non-transitory computer-readable medium of any of clauses 94 to 105, wherein the one or more first zone-specific SRSs comprise positioning SRSs.

[0328] Clause 107. The non-transitory computer-readable medium of any of clauses 94 to 106, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0329] Clause 108. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: transmit one or more zone-specific sounding reference signals (SRSs) while operating in a radio resource control (RRC) non-connected state and while camped on a first cell of a first SRS validity zone, wherein the one or more zone-specific SRSs are associated with a first uplink timing advance (TA); and transmit one or more physical layer uplink channels while operating in the RRC non-connected state and while camped on the first cell of the first SRS validity zone, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

[0330] Clause 109. The non-transitory computer-readable medium of clause 108, wherein: the first uplink TA is for a latest serving cell within the first SRS validity zone, and the second uplink TA is for the first cell.

[0331] Clause 110. The non-transitory computer-readable medium of clause 109, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more zone-specific SRSs and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0332] Clause 111. The non-transitory computer-readable medium of clause 109, wherein: the UE does not support multiple uplink TAs within a cell, both the one or more zone-specific SRSs and the one or more physical layer uplink channels are transmitted based on the first uplink TA, and the second uplink TA is the same as the first uplink TA.

[0333] Clause 112. The non-transitory computer-readable medium of any of clauses 109 to 111, wherein: a value of the first uplink TA is determined based on an uplink TA derivation rule, and the uplink TA derivation rule comprises: (1) a first uplink TA derivation rule comprising obtaining the value of the first uplink TA from the latest serving cell within the first SRS validity zone; or (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the first uplink TA.

[0334] Clause 113. The non-transitory computer-readable medium of any of clauses 109 and 112, wherein: the UE supports at least two uplink TAs within a cell, and the one or more zone-specific SRSs and the one or more physical layer uplink channels are scheduled to be transmitted in a same time slot.

[0335] Clause 114. The non-transitory computer-readable medium of clause 113, further comprising computer-executable instructions that, when executed by the UE, cause the UE to: refrain from transmitting the one or more zone-specific SRSs in the same time slot based on the one or more zone-specific SRSs and the one or more physical layer uplink channels being scheduled to be transmitted in the same time slot.

[0336] Clause 115. The non-transitory computer-readable medium of any of Clauses 113-114, wherein: the one or more region-specific SRS and the one or more physical layer uplink channels are scheduled to be transmitted in the same time slot based on the one or more region-specific SRS and the one or more physical layer uplink channels, both are transmitted in the same time slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0337] Clause 116. The non-transitory computer-readable medium of any of Clauses 113-115, wherein: the UE supports the one or more region-specific SRS and the one or more physical layer uplink channels to be transmitted in the same time slot based on different uplink TAs and a time gap is scheduled between the one or more region-specific SRS and the one or more physical layer uplink channels in the same time slot to permit the one or more region-specific SRS and the one or more physical layer uplink channels to be transmitted in the same time slot.

[0338] Clause 117. The non-transitory computer-readable medium of any of Clauses 113-115, wherein: the UE supports the one or more region-specific SRS and the one or more physical layer uplink channels to be transmitted in the same time slot based on different uplink TAs, there is no time gap between the one or more region-specific SRS and the one or more physical layer uplink channels based on the one or more region-specific SRS and the one or more physical layer uplink channels being scheduled in the same time slot, the one or more region-specific SRS and the one or more physical layer uplink channels are transmitted in the same time slot based on a same uplink TA, and the first uplink TA and the second uplink TA are the same uplink TA.

[0339] Clause 118. The non-transitory computer-readable medium of any of Clauses 113-117, wherein: the UE supports the one or more region-specific SRS and the one or more physical layer uplink channels to be transmitted in the same time slot based on different uplink TAs and there is no time gap between the one or more region-specific SRS and the one or more physical layer uplink channels based on the one or more region-specific SRS and the one or more physical layer uplink channels being scheduled in the same time slot, the one or more region-specific SRS or the one or more physical layer uplink channels are not transmitted in the same time slot.

[0340] Clause 119. The non-transitory computer-readable medium of any of clauses 109 to 118, wherein: the one or more region-specific SRSs are transmitted in a first time slot based on the first uplink TA, and the one or more physical layer uplink channels are transmitted in a second time slot based on the second uplink TA.

[0341] Clause 120. The non-transitory computer-readable medium of any of clauses 108 to 119, wherein: both the one or more region-specific SRSs and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

[0342] Clause 121. The non-transitory computer-readable medium of any of clauses 108 to 120, wherein the second uplink TA is obtained based on a random access procedure with the first cell.

[0343] Clause 122. The non-transitory computer-readable medium of any of clauses 108 to 121, wherein the one or more physical layer uplink channels comprise: one or more non-region-specific SRSs, one or more short data transmissions (SDTs), or any combination thereof.

[0344] Clause 123. The non-transitory computer-readable medium of any of clauses 108 to 122, wherein the one or more region-specific SRSs comprise positioning SRSs.

[0345] Clause 124. The non-transitory computer-readable medium of any of clauses 108 to 123, wherein the RRC non-connected state comprises: an RRC inactive state or an RRC idle state.

[0346] Those skilled in the art will understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that can be referenced throughout the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0347] Moreover, those skilled in the art will appreciate that the functions of the various example logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various example components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0348] The various illustrative logical blocks, modules, and circuits described in connection with the aspects disclosed herein can be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an ASIC, a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0349] The methods, sequences, and / or algorithms described in connection with the aspects disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in Random-Access Memory (RAM), flash memory, Read-Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal (e.g., an UE). In the alternative, the processor and the storage medium can reside as discrete components in a user terminal.

[0350] In one or more example aspects, the functions described can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions can be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0351] While the foregoing disclosure shows illustrative aspects of the disclosure, it should be noted that various changes and modifications could be made therein without departing from the scope of the disclosure as defined by the appended claims. For example, the functions, steps and / or actions of the methods described herein need not be performed in any particular order. Furthermore, although elements of the disclosure can be described or claimed in particular combinations, each combination should be considered as separate and discrete embodiments of the disclosure, rather than the practice of a combination. Additionally, it should be noted that none of the elements of the disclosure are required, unless explicitly recited by the claims. Also, as used herein, the terms “set,” “group,” and the like are intended to include one or more elements, and the terms “a,” “an,” and “the” are not intended to refer to one and only one unless otherwise explicitly stated. Furthermore, to the extent that the terms “includes,” “including,” “has,” “having” and / or “contains,” “containing,” are used, such terms are intended to be open-ended terms that also mean “comprising.” As used herein, the terms “based on” and “based upon” are intended to be open-ended terms that are to be interpreted as “based at least in part on” unless explicitly stated otherwise. Also, as used herein, the term “or” is intended to be the inclusive, open-ended term that can be used interchangeably with “and / or,” unless explicitly stated otherwise (e.g., if used in a series of two items, “or” can be interpreted as “one or the other, but not both,” while “and / or” can be interpreted as “one, the other, or both”). In addition, although process steps, algorithms or actions may be described or claimed in a particular sequential order, such processes can be configured to work in different sequences or manners, as long as the functionality remains the same. As such, any process claim that includes steps in a particular order is intended to embrace any additional process steps that mayaffect the functionality of the process, as long as such steps are performed in any suitable order. Additionally, although process steps, algorithms or actions may be described or claimed as being performed in a particular order, such processes can be configured to work in different sequences or manners, as long as the functionality remains the same. As such, any process claim that includes steps in a particular order is intended to embrace any additional process steps that mayaffect the functionality of the process, as long as such steps are performed in any suitable order.

Claims

1. A user equipment (UE), the user equipment (UE) comprising: one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: receive, via the one or more transceivers, one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, transmit, via the one or more transceivers, one or more first zone-specific SRSs based on the one or more SRS configurations and an uplink timing of the UE, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone in which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust a value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure with the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-zone of a plurality of sub-zones of the first SRS validity zone containing the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform a short data transmission (SDT), a non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

2. The UE of claim 1, wherein: the uplink TA derivation rule is indicated in the one or more SRS configurations, and the one or more SRS configurations indicate different uplink TA derivation rules for the one or more SRS validity zones.

3. The UE of claim 1, wherein the uplink TA derivation rule is determined based on whether a change in the downlink reference timing has exceeded the first threshold.

4. The UE of claim 3, wherein: ​ based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the second uplink TA derivation rule.

5. The UE of claim 3, wherein: based on the change in the downlink reference timing being less than the first threshold, the uplink TA derivation rule comprises the first uplink TA derivation rule, and based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

6. The UE of claim 3, wherein the uplink TA derivation rule comprises the second uplink TA derivation rule to prevent a change in the uplink timing of the UE from exceeding the second threshold.

7. The UE of claim 6, wherein based on the change in the downlink reference timing exceeding the first threshold, the uplink TA derivation rule comprises the third uplink TA derivation rule.

8. The UE of claim 6, wherein the second uplink TA derivation rule is applied by adjusting the uplink TA such that the uplink timing of the UE remains constant within the second threshold.

9. The UE of claim 3, wherein the downlink reference timing is for a latest serving cell within the first SRS validity zone.

10. The UE of claim 1, wherein an uplink transmission time of the one or more first zone-specific SRSs is the downlink reference timing plus the first value of the uplink TA.

11. The UE of claim 1, wherein the one or more first zone-specific SRSs comprise positioning SRSs.

12. The UE of claim 1, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

13. A user equipment (UE), the user equipment (UE) comprising: one or more memories; one or more transceivers; and one or more processors communicatively coupled to the one or more memories and the one or more transceivers, the one or more processors configured to: when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first sounding reference signal (SRS) validity zone, transmit, via the one or more transceivers, one or more zone-specific SRSs, wherein the one or more zone-specific SRSs are associated with a first uplink timing advance (TA); and when operating in the RRC non-connected state and when camped on the first cell of the first SRS validity zone, transmit, via the one or more transceivers, one or more physical layer uplink channels, wherein the one or more physical layer uplink channels are associated with a second uplink TA.

14. The UE of claim 13, wherein: the first uplink TA is for a latest serving cell within the first SRS validity zone, and the second uplink TA is for the first cell.

15. The UE of claim 13, wherein: both the one or more zone-specific SRS and the one or more physical layer uplink channels are transmitted based on the second uplink TA, and the first uplink TA is the same as the second uplink TA.

16. The UE of claim 13, wherein the second uplink TA is obtained based on a random access procedure with the first cell.

17. The UE of claim 13, wherein the one or more physical layer uplink channels comprise: one or more non-zone-specific SRS, one or more short data transmissions (SDTs), or any combination thereof.

18. The UE of claim 13, wherein the one or more zone-specific SRS comprise positioning SRS.

19. The UE of claim 13, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

20. A method of wireless communication performed by a user equipment (UE), the method comprising: receiving one or more sounding reference signal (SRS) configurations associated with one or more SRS validity zones, wherein each SRS validity zone of the one or more SRS validity zones comprises one or more cells; and transmitting one or more first zone-specific SRS based on the one or more SRS configurations and an uplink timing of the UE when operating in a radio resource control (RRC) non-connected state and when camped on a first cell of a first SRS validity zone of the one or more SRS validity zones, wherein the first value of the uplink TA is determined based on an uplink TA derivation rule, the uplink TA derivation rule comprising: (1) a first uplink TA derivation rule comprising obtaining a value of the uplink TA from a latest serving cell within an SRS validity zone in which the UE is associated; (2) a second uplink TA derivation rule comprising permitting the UE to autonomously adjust the value of the uplink TA; or (3) a third uplink TA derivation rule comprising obtaining the value of the uplink TA from a cell on which the UE is camped based on a random access procedure with the cell, and wherein the uplink TA derivation rule: (1) applies to all cells in a first sub-region of the first SRS validity zone that contains the first cell; (2) is indicated in the one or more SRS configurations; (3) is determined based on whether the UE is configured to perform short data transmission (SDT), non-zone-specific SRS transmission, or both; (4) is determined based on whether a change in the downlink reference timing exceeds a first threshold; or (5) is determined based on whether a change in the uplink timing of the UE exceeds a second threshold.

Images