Reference signal received power (RSRP) variation threshold reference and relations to timing access (TA) validance procedure for area-

Abstract

Techniques for wireless communication are disclosed. In an aspect, a user equipment (UE) obtains a first downlink reference timing and a first reference signal received power (RSRP) measurement from a first cell, where the first RSRP measurement is a first reference RSRP; determining that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) disconnected state; and obtaining, while in the RRC non-connected state, a second downlink timing and a second RSRP measurement from the second cell based on the first downlink reference timing having changed beyond a threshold, where the second RSRP measurement is a second reference RSRP.

Description

[0001] Cross Reference to Related Applications

[0002] This Patent Application claims the benefit of U.S. Provisional Application No. 63 / 494,729, entitled “REFERENCE SIGNAL RECEIVED POWER (RSRP) CHANGE THRESHOLD REFERENCE AND RELATION TO THE TIMING ADVANCE (TA) VALIDITY PROCEDURE FOR AREA-SPECIFIC SOUNDING REFERENCE SIGNALS (SRS) FOR POSITIONING,” filed April 6, 2023, and U.S. Non-Provisional Application No. 18 / 612,323, entitled “REFERENCE SIGNAL RECEIVED POWER (RSRP) CHANGE THRESHOLD REFERENCE AND RELATION TO THE TIMING ADVANCE (TA) VALIDITY PROCEDURE FOR AREA-SPECIFIC SOUNDING REFERENCE SIGNALS (SRS) FOR POSITIONING,” filed March 21, 2024, each of which is assigned to the assignee hereof and is hereby expressly incorporated by reference herein in its entirety. TECHNICAL FIELD

[0003] Aspects of the disclosure relate generally to wireless communication. BACKGROUND

[0004] Wireless communication systems have developed through various generations, including first-generation analog wireless phone services, second-generation (2G) digital wireless phone services (including interim 2.5G and 2.75G networks), third-generation (3G) high speed data, Internet-capable wireless services, and fourth-generation (4G) services (e.g., Long-Term Evolution (LTE) or WiMax). There are presently many different types of wireless communication systems in 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 access (GSM), and others.

[0005] 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 SUMMARY

[0006] The following presents a simplified summary relating 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 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.

[0007] In one aspect, a method of wireless communication performed by a user equipment (UE) includes obtaining, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, where the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determining that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtaining, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed by more than a threshold, where the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0008] In an aspect, a user equipment (UE) includes a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor configured to: obtain, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtain, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0009] In an aspect, a user equipment (UE) includes means for obtaining, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; means for determining that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and means for obtaining, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0010] 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: obtain, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtain, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0011] Other objects and advantages associated with the aspects disclosed herein will be apparent to those skilled in the art based on the accompanying drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0012] The accompanying drawings are presented to aid in the description of various aspects of the disclosure and are provided solely for illustration of the various aspects and are not intended as a definition of the limits of those aspects.

[0013] Figure 1 An example wireless communication system in accordance with aspects of the present disclosure is illustrated.

[0014] Figure 2A 、 Figure 2B and Figure 2C An example wireless network structure in accordance with aspects of the present disclosure is illustrated.

[0015] 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.

[0016] Figure 4 Different radio resource control (RRC) states available in New Radio (NR) in accordance with aspects of the present disclosure are illustrated.

[0017] Figure 5 Examples of various positioning methods supported in New Radio (NR) in accordance with aspects of the present disclosure are illustrated.

[0018] Figure 6 is a diagram illustrating an example frame structure in accordance with aspects of the present disclosure.

[0019] Figure 7A and Figure 7B Example deferred mobile terminated location request (MT-LR) procedures for downlink and uplink based positioning methods in accordance with aspects of the present disclosure are illustrated.

[0020] Figure 8 An example RRC “SRS-PosRRC-Inactive” IE in accordance with aspects of the present disclosure is illustrated.

[0021] Figure 9A and Figure 9B Example deferred MT-LR procedures for downlink and uplink based positioning methods in accordance with aspects of the present disclosure employing positioning SRS pre-configuration are illustrated.

[0022] Figure 10 is a diagram illustrating an example UE mobility scenario through multiple zones in accordance with aspects of the present disclosure.

[0023] Figure 11 is a diagram illustrating a preconfigured positioning sounding reference signal (SRS) structure in accordance with aspects of the present disclosure.

[0024] Figure 12 is a diagram illustrating a fourth rule for determining a valid timing advance (TA) and a new reference signal received power (RSRP) for RSRP change calculation, in accordance with aspects of the present disclosure.

[0025] Figure 13 An example method of wireless communication is illustrated in accordance with aspects of the present disclosure. DETAILED DESCRIPTION

[0026] Aspects of the present disclosure are provided in the following description and related drawings addressed to various examples provided for illustration 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 in order to not obscure the relevant details of the present disclosure.

[0027] Various aspects generally relate to wireless positioning. Some aspects more specifically relate to a timing advance (TA) validity procedure for positioning transmitted area-specific sounding reference signals (SRS). In some examples, in cases where an area-specific SRS configuration for positioning is employed, if a user equipment (UE) determines that a downlink reference time has changed, the UE can autonomously adjust a previous valid TA, a new valid TA can be received, or the UE can determine that a new valid TA is equal to or very similar to the previous valid TA. More specifically, the UE can obtain a first downlink reference timing and a first reference signal received power (RSRP) measurement from a first cell, where the first RSRP measurement is a first reference RSRP for RSRP change calculation. The UE can then determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state. The UE can then obtain a second downlink timing and a second RSRP measurement from the second cell while in the RRC non-connected state based on the first downlink reference timing having changed more than a threshold, where the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0028] 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 providing rules for UE behavior when the UE determines that a downlink reference time has changed, the described techniques can be used to enable the UE to autonomously adjust a reference RSRP when adjusting a valid TA.

[0029] 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.

[0030] 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, the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or combinations of both.

[0031] Furthermore, 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, and that the disclosed aspects can not be limited to any particular type of

[0032] 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 noted. 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 device-to-device (D2D) protocol, e.g., Bluetooth, WiFi Direct, LTE D2D, etc. UEs can also communicate with other devices, e.g., servers, using wired or wireless communication protocols.

[0033] A base station can operate according to one of several 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) Node B (also referred to as a gNB or gNodeB), etc. Base stations can be used primarily to support wireless access by UEs, including supporting data, voice, and / or signaling connections for the supported UEs. In some systems, a base station can provide only edge node signaling functions, while in other systems it can provide additional control and / or network management functionality. A UE can communicate with a base station via downlink and uplink signals. Downlink signals can be transmitted by a base station to a UE, and uplink signals can be transmitted by a UE to a base station. Transmissions by a base station to a UE can be referred to as transmissions on a downlink channel, and transmissions by a UE to a base station can be referred to as transmissions on an uplink channel. A UE can also communicate with other UEs, e.g., using a device-to-device (D2D) protocol, e.g., Bluetooth, WiFi Direct, LTE D2D, etc.

[0034] 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) signals 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 interpreted to refer to particular TRPs of the base station.

[0035] In some implementations that support positioning of UEs, a base station can not support wireless access by UEs (e.g., can not support data, voice, and / or signaling connections for UEs), but can instead transmit reference signals to UEs to be measured by the UEs and / or can receive and measure signals transmitted by UEs. Such a base station can be referred to as a positioning beacon (e.g., where signals are transmitted to UEs) and / or as a location measurement unit (e.g., where signals from UEs are received and measured).

[0036] 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 it is clear from the context that the term “signal” refers to a wireless signal or an RF signal, an RF signal can also be referred to as a “wireless signal” or simply a “signal.”

[0037] 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.

[0038] 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.

[0039] The base stations 102 can perform functions such as, but not limited to, those described below with respect to one or more of: transport 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.

[0040] Base station 102 can wirelessly communicate with UE 104. Each base station in base station 102 can provide communication coverage for a corresponding geographic coverage area 110. In one aspect, one or more cells can be supported by base station 102 in each geographic coverage area 110. A “cell” is a logical communication entity used to communicate with a base station (e.g., via a frequency resource, referred to as a carrier frequency, component carrier, carrier, or frequency band, etc.) and can be associated with an identifier (e.g., Physical Cell Identifier (PCI), Enhanced Cell Identifier (ECI), Virtual Cell Identifier (VCI), Cell Global Identifier (CGI), etc.) used to distinguish cells operating via the same or different carrier frequencies. In some cases, different cells can be configured according to different protocol types that can provide access for different types of UEs (e.g., Machine Type Communication (MTC), Narrowband IoT (NB-IoT), Enhanced Mobile Broadband (eMBB), or other protocol types). Because a cell is supported by a specific base station, the term “cell” can refer to either or both of the logical communication entity and the base station supporting the logical communication entity, depending on the context. Furthermore, since the TRP is typically the 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 the geographical coverage area of ​​a base station (e.g., a sector), as long as the carrier frequency can be detected and used for communication within a portion of the geographical coverage area 110.

[0041] While the geographic coverage areas 110 of adjacent macro cell base stations 102 may partially overlap (e.g., in handover areas), some areas within geographic coverage areas 110 may substantially overlap with larger geographic coverage areas 110. For example, a small cell base station 102' (labeled "SC" for "small cell") may have a geographic coverage area 110' that substantially overlaps with the geographic coverage areas 110 of one or more macro cell base stations 102. A network that includes both small cell base stations and macro cell base stations can be referred to as a heterogeneous network. A heterogeneous network may also include a home eNB (HeNB) that can provide service to a restricted group referred to as a Closed Subscriber Group (CSG).

[0042] The communication link 120 between base station 102 and UE 104 may include uplink (also known as reverse link) transmission from UE 104 to base station 102 and / or downlink (DL) (also known as forward link) transmission from base station 102 to UE 104. The communication link 120 may use MIMO antenna techniques, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may use one or more carrier frequencies. Carrier allocation may be asymmetric for the downlink and uplink (e.g., more or fewer carriers may be allocated to the downlink compared to the uplink).

[0043] The 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 prior to communicating to determine whether the channel is available.

[0044] The small cell base stations 102' can operate in a licensed 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. The NR in unlicensed spectrum can be referred to as NR-U. The LTE in unlicensed spectrum can be referred to as LTE-U, License Assisted Access (LAA), or MulteFire ® .

[0045] 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 to communicate with UEs 182. Extremely high frequency (EHF) is the part of the radio frequency spectrum that lies between 30 GHz and 300 GHz. It lies just beyond the band of microwaves; it is around 1 millimeter to 10 millimeters wavelength, respectively. 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 the centimeter wave band. Communications using the mmW / near mmW radio frequency band have extremely 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 the mmW communication links 184 to compensate for the extremely high path loss and short range. Further, it should be appreciated that in an alternative configuration one or more base stations 102 can also transmit using mmW or near mmW and beamforming. Thus, it should be understood that the preceding illustration is merely examples and should not be construed as limiting various aspects disclosed herein.

[0046] Transmit beamforming is a technique used to focus the RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts a RF 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 in relation 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 directionality 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 that broadcast the RF signal. For example, the network node can use an array of antennas (referred to as a “phased array” or “antenna array”), which in effect does not move the antennas, but the RF beams can be “steered” to point in different directions. Specifically, the RF current from the transmitters 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 one another in an undesired direction.

[0047] Transmit beams can be quasi co-located, which means that they appear to have the same parameters at 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, then the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, average delay, and delay spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type B, then the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type C, then the receiver can use the source reference RF signal to estimate the Doppler shift and average delay of the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type D, then the receiver can use the source reference RF signal to estimate the spatial receive parameter of the second reference RF signal transmitted on the same channel.

[0048] In receive beamforming, a 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 in other directions, or that the beam gain in that direction is the highest compared to the beam gain in that direction of all other receive beams available to the receiver. 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.

[0049] The transmit beam and the receive beam can be spatially related. Spatially related 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 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 the base station based on parameters of the receive beam.

[0050] Note that depending on the entity forming the “downlink” beam, the beam can be a transmit beam or a receive beam. For example, if a base station is forming a downlink beam to transmit a reference signal to a UE, the downlink beam is a transmit beam. However, if a UE is forming a downlink beam, the downlink beam is a receive beam to receive a 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 a base station is forming an uplink beam, the uplink beam is an uplink receive beam, while if a UE is forming an uplink beam, the uplink beam is an uplink transmit beam.

[0051] The electromagnetic spectrum is often subdivided based on frequency / wavelength into various classes, bands, channels, etc. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz - 7.125 GHz) and FR2 (24.25 GHz - 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 referred to (interchangeably) 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 GHz - 300 GHz. Following the initial 5G NR deployments, additional operating bands are expected to be licensed, such as FR1 bands from 7.125 GHz to 24.25 GHz and FR2 bands from 52.6 GHz to 71 GHz and 114.25 GHz to 300 GHz. ® Extremely high frequency (EHF) bands (30 GHz to 300 GHz) that are identified as “millimeter wave” frequency bands.

[0052] The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified operating bands for these mid-band frequencies as frequency range designation FR3 (7.125 GHz to 24.25 GHz). Bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and thus can effectively extend the features of FR1 and / or FR2 to mid-band frequencies. Moreover, even higher bands are currently under exploration to extend 5G NR operations beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR4-a 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.

[0053] With the above aspects in mind, unless specifically stated otherwise, it should be understood that the term “Sub-6 GHz” or the like is used herein to generically refer to 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 the term “millimeter wave” or the like is used herein to generically refer to 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 band.

[0054] 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 (however, this is not always the case). The secondary carriers are carriers 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 carriers can be carriers in an unlicensed frequency. The secondary carriers can contain only necessary signaling information and signals, e.g., those that are UE-specific can not be present in the secondary carriers since both the primary uplink and 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 carriers. 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 the 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," and the like can be used interchangeably.

[0055] For example, still referring to Figure 1 One of the frequencies used by the macrocell base station 102 can be an anchor carrier (or "PCell") and the other frequencies used by the macrocell base station 102 and / or mmW base station 180 can be secondary carriers ("SCells"). The 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 a doubling of the data rate (i.e., 40 MHz) compared to the data rate obtained with a single 20 MHz carrier.

[0056] The wireless communications system 100 can also include UE 164, which can be in communication with macro cell base station 102 over communication link 120 and / or mmW base station 180 over mmW communication link 184. For example, macro cell base station 102 can support PCell and one or more SCells for UE 164, and mmW base station 180 can support one or more SCells for UE 164.

[0057] In some cases, UEs 164 and 182 can be capable of sidelink communications. A sidelink-capable UE (SL-UE) 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 communicate with each other directly using a PC5 interface (i.e., the air interface between sidelink-capable UEs) over wireless sidelink 160. Wireless sidelink (or “sidelink” for short) 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 communications 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 utilizing sidelink communications can be within the geographic coverage area 110 of base station 102. Other SL-UEs in such a group can be outside the geographic coverage area 110 of base station 102, or be unable to receive transmissions from base station 102 for other reasons. In some cases, groups of SL-UEs communicating via sidelink communications 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, base station 102 facilitates scheduling of resources for sidelink communications. In other cases, sidelink communications are performed between SL-UEs without involvement of base station 102.

[0058] 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.

[0059] 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.

[0060] In Figure 1 the example 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 that UEs 104 can use as a standalone 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 enable receivers (e.g., UEs 104) to determine their location on or above the Earth based, at least in part, on positioning signals (e.g., signals 124) received 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. UEs 104 can include one or more specialized receivers designed specifically for receiving signals 124 in order to derive geographic location information from SVs 112.

[0061] In a satellite positioning system, the use of signals 124 can be augmented by various satellite-based augmentation systems (SBASs), which can be associated with one or more global and / or regional navigation satellite systems or which 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 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-functional Satellite Augmentation System (MSAS), the GPS Aided Geo Augmented Navigation or GPS and Geo Augmented Navigation system (GAGAN), and / or the like. Thus, as used herein, a satellite positioning system can include any combination of one or more global and / or regional navigation satellite systems, associated with such one or more satellite positioning systems.

[0062] 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, instead of or in addition to communication signals from terrestrial base stations 102, UEs 104 can receive communication signals (e.g., signals 124) from SVs 112.

[0063] The wireless communications system 100 can also include one or more UEs, such as UE 190, that indirectly connect 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.).

[0064] 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

[0065] 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).

[0066] 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 5GC 260 can also include a Data Management Function (DMF) 268, which can be a component of the 5GC 210 in some embodiments. The DMF 268 can be a control plane function that provides data management services for the 5GC 210. The DMF 268 can be responsible for managing data lifecycle policies, data storage, and data retrieval for the 5GC 210. The DMF 268 can also be responsible for providing data management services for the 5GC 210, including data management for the AMF 264, the SMF 266, the SMSF, the AUSF, the SEAF, the PCF 272, the NRF 274, the UDM 278, the DM 280, and the N3IWF 282. The DMF 268 can also be responsible for providing data management services for the 5GC 210, including data management for the 5G ProSe ® functionality for access to unlicensed spectrum.

[0067] UPF 262 functions include acting as an anchor point for intra- / inter-RAT mobility (when applicable), acting as an 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 one or more “end markers.” UPF 262 can also support transfer of location services messages between UE 204 and a location server, such as the SLP 272, over the user plane.

[0068] The SMF 266 functions 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

[0069] 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).

[0070] 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.

[0071] 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.

[0072] 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.

[0073] Deployment 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 units (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.

[0074] 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 distributed 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, namely a virtual central unit (VCU), virtual distributed unit (VDU), or virtual radio unit (VRU).

[0075] 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 used 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.

[0076] 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 communicate with one or more DUs 285 (e.g., gNB-DUs 228) via respective fronthaul links, such as an Fl interface. The DUs 285 can communicate with one or more radio units (RUs) 287 (e.g., gNB-RUs 229) via respective front-haul links. The RUs 287 can communicate 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.

[0077] 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. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of these units, can be configured to communicate with one or more of the other units via the transmission mediums. For example, the units can include wired interfaces configured to receive or transmit signals to one or more of the other units over a wired transmission medium. Additionally, the units can include wireless interfaces, which can include receivers, transmitters, or transceivers (such as RF transceivers) configured to receive or transmit signals, or both, to one or more of the other units over a wireless transmission medium.

[0078] In some aspects, CU 280 can host one or more higher layer control functions. Such control functions can include RRC, PDCP, service data adaptation protocol (SDAP), etc. Each control function can be implemented with 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.

[0079] 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 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 accordance with a functional split, such as a functional split defined by the Third Generation Partnership Project (3GPP ® ) in some aspects, DU 285 can further 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 DU 285 or with control functions hosted by CU 280.

[0080] Lower layer functionality can be implemented by one or more RUs 287. In some deployments, RUs 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 a fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, or physical random access channel (PRACH) extraction and filtering, among others) or both based at least in part on a functional split, such as a lower layer functional split. In such an architecture, RUs 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 RUs 287 can be controlled by a corresponding DU 285. In some scenarios, this configuration can enable DUs 285 and CUs 280 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

[0081] The SMO framework 255 can be configured to support RAN deployment and provisioning 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, CUs 280, DUs 285, RUs 287, and near-RT RICs 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.

[0082] 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, application / features in near-RT RIC 259 of artificial intelligence / machine learning (AI / ML) workflow or policy-based steering. 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 over 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.

[0083] 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 through the SMO framework 255, such as via reconfiguration of Ol, or via creation of RAN management policies, such as Al policies.

[0084] Figure 3A 、 Figure 3B and Figure 3C Several example components (represented by corresponding blocks) are illustrated that can be incorporated into the UE 302 (which can correspond to any of the UEs described herein), the base station 304 (which can correspond to any of the base stations described herein), and the network entity 306 (which can correspond to or embody any of the network functions described herein, including the location server 230 and the LMF 270, or alternatively can be independent from the network functions described herein). The components illustrated for the UE 302, the base station 304, and / or the network entity 306 can individually or collectively implement any of the 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. Moreover, 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.

[0085] 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.

[0086] 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 ®, PC5, dedicated short-range communications (DSRC), wireless access for vehi cl e environments (WAVE), near-field communications (NFC), ultra-wideband (UWB), etc.) to communicate with other network nodes (such as other UEs, access points, base stations, etc.). The short-range wireless transceivers 320 and 360 can be variously configured for transmitting and encoding signals 328 and 368 (e.g., messages, indications, information, etc.), respectively, and vice-versa, in accordance with a designated RAT. Specifically, the short-range wireless transceivers 320 and 360 include one or more transmitters 324 and 364, respectively, for transmitting and encoding signals 328 and 368, respectively, and one or more receivers 322 and 362, respectively, 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, ZIGBEE ® and / or Z-WAVE ® transceivers, NFC transceivers, UWB transceivers, or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceivers.

[0087] At least in some cases, the UE 302 and the base station 304 also include satellite signal receivers 330 and 370. The satellite signal receivers 330 and 370 can be connected to one or more antennas 336 and 376, respectively, and can provide means for receiving and / or measuring satellite positioning / communication signals 338 and 378, respectively. In cases where the satellite signal receivers 330 and 370 are satellite positioning system receivers, the satellite positioning / communication signals 338 and 378 can be global positioning system (GPS) signals, global navigation satellite system (GLONASS ® ) signals, Galileo signals, Beidou signals, Indian Regional Navigational Satellite System (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. In cases where the satellite signal receivers 330 and 370 are non-terrestrial network (NTN) receivers, the satellite positioning / communication signals 338 and 378 can be communication signals (e.g., carrying control and / or user data) originating from a 5G network. The satellite signal receivers 330 and 370 can include any suitable hardware and / or software for receiving and processing satellite positioning / communication signals 338 and 378, respectively. The satellite signal receivers 330 and 370 can request information and operations as appropriate to other systems, and, at least in some cases, perform calculations using measurements obtained by any suitable satellite positioning system algorithm to determine the location of the UE 302 and the base station 304, respectively.

[0088] 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 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 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.

[0089] 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 allows 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 allows 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.

[0090] 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.

[0091] UE 302, base stations 304, and network entities 306 also include other components that can be beneficial in conjunction with the operations disclosed herein. For example, UE 302, base stations 304, and network entities 306 each include one or more processors 332, 384, and 394 for providing functionality

[0092] 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 processor 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 processor 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 a memory module stored in the memory 340, 386, and 396, respectively, which when executed by the processor 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.

[0093] 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 orientation sensors to provide the ability to calculate positioning in two-dimensional (2D) and / or three-dimensional (3D) coordinate systems.

[0094] 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.

[0095] 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.

[0096] 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

[0097] 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.

[0098] In the downlink, 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.

[0099] 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.

[0100] Channel estimates derived by the channel estimator from a reference signal 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.

[0101] 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 antenna 356. The receiver 352 recovers information modulated onto an RF carrier and provides the information to the one or more processors 384.

[0102] 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.

[0103] 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, and the network entity 306 each include various components of a computing device, such as one or more processors 312, 354, and 384, respectively, and storage that stores instructions 314, 356, and 386, respectively, which are executed by the respective processors 312, 354, and 384, respectively, to cause the respective devices to perform various acts or functions. Additionally, the UE 302, the base station 304, and the network entity 306 each include respective communication interfaces 316, 358, and 388, respectively, that are configured to communicate with one another and / or with other devices over one or more wired or wireless networks. The communication interfaces 316, 358, and 388 can each include one or more antennas, antenna arrays, radio frequency (RF) transmitters, RF receivers, transceivers, amplifiers, frequency filters, control components, and / or other like communication components. Figures 3A-3C The various components in the UE 302, the base station 304, and the network entity 306 are optional in alternative configurations, and various aspects include configurations that can vary due to design choices, 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 a personal computer (PC) or a 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. As 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.

[0104] The various components of the UE 302, the base station 304, and the network entity 306 can be communicatively coupled to one another 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.

[0105] 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 390-398 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.

[0106] 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).

[0107] 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.

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] A location estimate can be referred to by other names, such as a position estimate, location, position, position 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 verbal 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 position is expected to be included with some specified or default confidence level).

[0119] Various frame structures can be used to support downlink and uplink transmissions between network nodes (e.g., base stations and UEs). Figure 6 FIG. 600 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.

[0120] 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.

[0121] LTE supports a single set of parameters (subcarrier spacing (SCS), symbol length, etc.). In contrast, NR can support multiple sets of parameters (µ), for example, subcarrier spacings of 15kHz (µ=0), 30kHz (µ=1), 60kHz (µ=2), 120kHz (µ=3), and 240kHz (µ=4) or larger can be available. Within each subcarrier spacing, there are 14 symbols per time slot. For a 15kHz SCS (µ=0), there is one time slot per subframe, 10 time slots per frame, a time slot duration of 1 millisecond (ms), a symbol duration of 66.7 microseconds (µs), and a maximum nominal system bandwidth (in MHz) of 4K FFT size. For a 30kHz SCS (µ=1), there are two time slots per subframe, 20 time slots per frame, a time slot duration of 0.5ms, a symbol duration of 33.3µs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size. For a 60kHz SCS (µ=2), there are four time slots per subframe, 40 time slots per frame, a time slot duration of 0.25ms, a symbol duration of 16.7µs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size. For a 120kHz SCS (µ=3), there are eight time slots per subframe, 80 time slots per frame, a time slot duration of 0.125ms, a symbol duration of 8.33µs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size. For a 240kHz SCS (µ=4), there are 16 time slots per subframe, 160 time slots per frame, a time slot duration of 0.0625ms, a symbol duration of 4.17µs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size.

[0122] exist Figure 6 In the example, a parameter set of 15kHz is used. Therefore, in the time domain, a 10ms frame is divided into 10 equal-sized subframes, each subframe being 1ms long, and each subframe including one time slot. Figure 6 In the diagram, 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.

[0123] A resource grid can be used to represent time slots, each time slot comprising one or more concurrent resource blocks (RBs) (also known as physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into multiple resource elements (REs). An RE can correspond to a symbol length in the time domain and a subcarrier in the frequency domain. 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.

[0124] 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”).

[0125] 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.

[0126] 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.

[0127] 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}.

[0128] 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 {4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots with µ = 0, 1, 2, 3. The repetition factor can have a length selected from {1, 2, 4, 6, 8, 16, 32} slots.

[0129] 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 on whether the TRP and beam on which the PRS is transmitted is known to the UE.

[0130] 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.”

[0131] 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, and the minimum value is 24 PRBs and the maximum value is 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.

[0132] The concept of a frequency layer is somewhat similar 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.

[0133] 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. The 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.

[0134] 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").

[0135] 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 / tonal 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. 4, 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.

[0136] 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}.

[0137] Generally, 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 specially 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.”

[0138] 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)).

[0139] 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. Moreover, 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”. Moreover, 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”.

[0140] Low power high accuracy positioning (LPHAP) techniques have been introduced that allow a UE to perform positioning operations while in an RRC inactive state (RRC inactive state 430). With small data transmission (SDT) features, a UE can also transmit data and / or NAS signaling while remaining in this RRC inactive state, allowing the UE to participate in downlink and uplink based positioning procedures and / or uplink based positioning procedures, and not just downlink based positioning procedures.

[0141] 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 (e.g., UE) can be provided with positioning instructions (e.g., positioning method to use, QoS, etc.) and possibly assistance data. The target device then monitors for an event occurrence, performs location measurements upon detecting the 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. The procedure has been defined to allow the UE to remain in an RRC inactive state during the positioning measurement and event reporting phases.

[0142] 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.

[0143] 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.

[0144] At some point in time, the UE 204 is released from RRC connected to RRC inactive by the last serving gNB through “RRCRelease” with “SuspendConfig”.

[0145] At Stage 2, the UE 204 monitors for the occurrence of the triggered or periodic event requested during Stage 1.

[0146] 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 of the UE 204 at the time the UE 204 performs stage 3 can be the same or different from the last serving gNB where the UE 204 was released to RRC Inactive state.

[0147] 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.

[0148] At stage 5, the LMF 270 transmits a New Radio Positioning Protocol Type A (NRPPa) Position Information Request message to the receiving gNB to request UL-SRS for the target device (i.e., the UE 204).

[0149] At stage 6, the receiving gNB determines the resources available for UL-SRS.

[0150] At stage 7, the receiving gNB provides the UL-SRS configuration information to the LMF 270 in a NRPPa Position Information Response message.

[0151] At stage 8, the LMF 270 transmits an NRPPa Measurement Request including the UL-SRS measurement configuration to the gNB group.

[0152] At stage 9, the LMF 270 transmits a supplemental service (SS) LCS event report acknowledgment to the receiving gNB. Then, at stage 9b, the receiving gNB provides the SS event report acknowledgment to the UE 204 via a subsequent DL SDT.

[0153] 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.

[0154] At stage 11, the UE 204 performs DL-PRS measurements and each configured TRP performs UL-SRS measurements.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] At stage 15, when all LPP Provide Location Information messages have been received, the LMF 270 transmits an SS LCS event report acknowledgment to the receiving gNB. Then, at stage 15b, the receiving gNB provides the SS event report acknowledgment to the UE 204 via a subsequent DL SDT.

[0159] At stage 16, the receiving gNB transmits an “RRCRelease” message with “suspendConfig” to keep the UE 204 in RRC Inactive state.

[0160] 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.

[0161] In the foregoing procedure, whenever a triggered 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, e.g., large signaling activity for periodic events with a relatively small periodicity (e.g., 15 seconds to 30 seconds), and thus additional latency and processing, which can also adversely affect the power consumption at the target device.

[0162] 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, e.g., at stage 1 of the initialization phase of the deferred MT-LR procedure (stages 1-3 in Figure 7A This 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.

[0163] 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. The SRS for positioning is typically 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.

[0164] 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.

[0165] 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

[0166] 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.

[0167] ​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.

[0168] 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.

[0169] 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 for positioning parameters into 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.

[0170] The pre-configuration will include the part (a) parameter set. The remaining parameters (part (b)) will 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

[0171] Figure 9A and Figure 9B An example deferred MT-LR procedure with positioning SRS pre-configuration for downlink and uplink based positioning methods (e.g., multi-RTT) 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). ​

[0172] At phase 1a, LMF 270 transmits an NRPPa location information request message to serving gNB 222, including a request for a pre-configured location SRS. This request may include one or more "Requested SRS Transmission Characteristics" (IEs), each defining the desired location SRS configuration. LMF 270 may include path loss reference, spatial relationships, and SSB information for each gNB in ​​the area. This "auxiliary information" may be used by the serving / receiving gNB 222 to compile a portion of the parameters (b) that will be valid for the current UE location at a later time. For example, for each considered cell ID, the auxiliary information may include a list of neighboring cells with SSB or DL-PRS information that can be used as a path loss reference or spatial relationship for location SRS.

[0173] At phase 1b, the serving gNB 222 determines one or more location SRS configurations and provides these configurations to the target device (UE 204) so ​​that the target device can send location SRS at a later time (i.e., the target device does not send any location SRS when pre-configured). Each location SRS configuration has the following characteristics: Figure 8 The associated identifier is shown. Each location SRS may have a validity period and / or a validity area. The "validity area" may be defined by a list of cell IDs that define where the SRS configuration is applicable / valid.

[0174] At phase 1c, the service gNB 222 provides the LMF 270 with a pre-configured set of location SRSs (e.g., one or more "SRS Configuration" IEs, where each location SRS has as follows). Figure 8 (As shown by the associated ID).

[0175] At phase 3, after (or slightly earlier) an event is detected, UE 204 transmits an SRS activation request message along with an RRC recovery request to receiving gNB 222. The SRS activation request message may include an identifier of the desired pre-configured SRS configuration to be activated (e.g., in priority order).

[0176] 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.

[0177] At stage 5, the receiving gNB 222 can then transmit an SRS activation message to the UE 204 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.

[0178] At stage 6, the receiving gNB 222 transmits an NRPPa Positioning Information Update message to the LMF 270 including the ID of the activated positioning SRS.

[0179] At stage 7, the LMF 270 transmits an NRPPa Measurement Request message to the gNB / TRP set including the positioning SRS measurement configuration (i.e., based on the ID received at stage 6).

[0180] At stage 8, the receiving gNB 222 transmits an RRC Release message to the UE 204 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

[0181] 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

[0182] 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 in 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 cells in which the UE camps / connects. The preconfigured SRS configuration is valid / selected if the UE camps in or connects to one of the cells indicated within the list of cells in the area ID.

[0183] 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.

[0184] 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 in or connects to one of the cells associated with areaID4 (e.g., PCI3, PCI7, PCI11, PCI15).

[0185] ​To enable greater network control of 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 allowed 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 where 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.

[0186] 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 RRC Inactive state 430. Specifically, the “SRS-PosRRC-Inactive” IE provides a list 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 where the SRS configuration is valid. If the UE reselects to a cell included in the LPP “Area-ID-CellList” IE, the UE is allowed 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.

[0187] 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.

[0188] A UE transmits SRS and other uplink transmissions according to its uplink timing. The uplink timing is simply the downlink reference timing plus an uplink timing advance (TA). The downlink reference timing (or simply “downlink timing”) is defined as the time of reception of the (temporally) first detected path of a corresponding downlink frame from a reference cell (e.g., the UE’s serving cell or the cell in which the UE is camped). The uplink TA accounts for 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 farther away from the cell having a longer propagation delay and thus a larger TA.

[0189] The uplink TA helps to ensure that uplink transmissions from all UEs are synchronized when received by the cell. When in an RRC connected state (RRC connected state 420), a UE is configured with the uplink TA by its serving cell. However, when moving between cells while in an RRC inactive or idle state (collectively referred to as an “RRC non-connected” state), the uplink TA can be different for the cell in which the UE is currently camped. This can be a problem in cases where the UE is configured to transmit SRS for positioning while in an RRC inactive state, as these transmissions can not occur at the time expected by the network and / or can interfere with other uplink transmissions from other UEs, for example.

[0190] In some cases, it can be feasible to configure a TA timer that is specific to the positioning SRS validity area for a UE in an RRC inactive state. For example, the TA timer can have a larger value when the UE is in an RRC inactive state than when the UE is in an RRC connected state. Additionally, it can be feasible to use a zone-specific RSRP change threshold for TA validation.

[0191] 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 transmission of SRS for positioning by a UE in an RRC inactive state within a positioning SRS validity area. As a first option or first derivation 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 change, and the change can be sudden if the UE suddenly changes the cell used for downlink timing determination.

[0192] As a second TA derivation rule, the UE can autonomously adjust the uplink TA. How the UE adjusts the TA can depend on UE implementation or based on the TA from the last serving cell and downlink time difference measurements to SSBs from 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 so that the resulting sum (i.e., uplink timing) remains the same.

[0193] 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., random access channel (RACH) procedure) to a new cell and receive the TA value of the new cell. As the UE moves around, the UE should track the uplink TA value associated with each cell.

[0194] As noted above, it can also be feasible to use area-specific RSRP change threshold for TA validation. In this case, as the UE moves, the UE measures the RSRP of SSBs broadcast by nearby cells and compares these RSRPs to a reference RSRP. Currently, the reference RSRP is defined as the RSRP of the UE’s last / recent serving cell. However, like the TA, the UE can become far enough away from the last serving cell while in RRC non-connected state (due to mobility) such that it no longer makes sense to continue using the RSRP as the reference RSRP.

[0195] The present disclosure provides techniques for selecting a reference RSRP for area-specific SRS resource RSRP change threshold calculation. The reference RSRP should be obtained from the latest cell for which the UE has determined its valid TA, where in the context of validity area-specific SRS (also referred to as multi-cell SRS or simply area-specific SRS), the valid TA can be determined according to one of several cases if the associated TA timer has not expired.

[0196] As a first case, the UE can determine that the downlink reference time has changed, and the UE can autonomously adjust the previous valid TA so that the uplink timing remains the same. Here, "remains the same" means within a given threshold / maximum tolerance. That is, the uplink timing can change (adjust) over time as long as it changes (adjusts) less than the threshold / maximum tolerance (i.e., changes gradually). The threshold / maximum tolerance can be configured to the UE together with the zone-specific RSRP change threshold, or the threshold / maximum tolerance can be specified in UE requirements (e.g., the threshold / maximum tolerance can depend on SCS, numerology, frequency range (e.g., FR1, FR2), frequency band, signal-to-noise ratio (SNR), and / or RSRP level).

[0197] The TA autonomous adjustment can be performed only if it has been determined that the downlink reference time has changed beyond a given threshold or each time a new camped cell (i.e., a cell in which the UE is camped in RRC non-connected state) is identified. The threshold can be configured to the UE together with the zone-specific RSRP change threshold, or the threshold can be specified in UE requirements (e.g., the threshold can depend on SCS, numerology, frequency range, frequency band, SNR, and / or RSRP level).

[0198] As a second case, the new valid TA can be received through explicit signaling from the latest serving cell. This is the currently defined behavior.

[0199] As a third case, the UE can determine that the downlink reference time has changed, and the UE can determine that the new valid TA is equal to the previous valid TA. In this case, the reference RSRP also does not change. This determination can occur if the downlink reference time has changed by a small amount compared to a threshold. The threshold can be configured to the UE together with the zone-specific RSRP change threshold, or the threshold can be specified in UE requirements (e.g., the threshold can depend on SCS, numerology, frequency range, frequency band, SNR, and / or RSRP level).

[0200] The aforementioned situations can be expressed by the following rules / heuristics: (1) If the TA timer has expired, the previous TA is invalid. (2) Otherwise, if the UE receives a new TA value from the network via explicit signaling, the TA value is the new valid TA. (3) Otherwise, if the received downlink timing has changed (e.g., the cell has changed) by less than a threshold, the UE maintains the same valid TA, and the reference RSRP used for RSRP change calculation remains unchanged. Here, "maintain the same" means exactly the same or within a given threshold / maximum tolerance. That is, the TA can change (adjust) over time as long as it changes (adjusts) by less than the threshold / maximum tolerance (i.e., changes gradually). (4) Otherwise, if the received downlink timing has changed beyond a threshold (e.g., the UE measures a new cell and makes that new cell its new cell, and therefore the UE has a new received downlink timing and a new RSRP for that cell), the UE can autonomously and based on the UE-specific implementation adjust the TA to obtain a new valid TA and a new reference RSRP used for RSRP change calculation.

[0201] Referring further to rule (4), the autonomous TA adjustment should not exceed the measured downlink time difference between the downlink timing used to derive the previous valid TA and the newly measured downlink timing. The difference between the new reference RSRP and the previous reference RSRP should not exceed a second threshold; otherwise, the UE should consider the newly determined TA invalid. Additionally, the UE should perform downlink timing measurements on SSBs that are temporally close (e.g., within a time window) to avoid clock drift affecting measurement accuracy. The measurement accuracy of this SSB-based RSTD can be specified in the applicable wireless communication standard.

[0202] When the UE determines to update the previous valid TA to a new valid TA based on the third or fourth rule mentioned above, the UE should also update the RSRP reference value. The UE will use the reference value to determine whether the new valid TA will still be valid in the future.

[0203] Figure 12 Figure 1200 illustrates the fourth rule for determining the effective TA and for calculating the new reference RSRP variation according to various aspects of this disclosure. Figure 12 As shown, at stage 1210, when the UE is in RRC connected mode or in RRC disconnected mode with SDT (e.g., RRC inactive state 430), the UE receives a valid TA from the network (e.g., the UE's current serving cell). In this case, there is a first RSRP reference for determining / calculating RSRP changes.

[0204] At stage 1220, at some later point in time, the UE camps in a new cell that has a new downlink reference timing but has the same SRS configuration (i.e., has the same zone-specific SRS configuration). The UE then determines whether to apply rule (3) or (4) above. Here, the UE determines that rule (4) applies, resulting in a new effective TA. This also results in a second RSRP reference for determining / calculating the RSRP change.

[0205] Note that the first cell and the second cell for the downlink reference timing can be the same cell. In this case, the first downlink reference timing for the cell can be based on a first SSB from the cell, and the second downlink reference timing for the cell can be based on a second SSB from the cell.

[0206] Figure 13 An example method 1300 of wireless communication in accordance with aspects of the present disclosure is illustrated. In an aspect, the method 1300 can be performed by a UE (e.g., any of the UEs described herein).

[0207] At 1310, the UE obtains, from a first cell, a first downlink reference timing and a first RSRP measurement, where the first RSRP measurement is a first reference RSRP for RSRP change calculation. In an aspect, the operation 1310 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, the memory 340, and / or the positioning component 342, any or all of which can be considered means for performing this operation.

[0208] At 1320, the UE determines, based on a cell reselection from the first cell to a second cell performed while in an RRC non-connected state, that the first downlink reference timing has changed. In an aspect, the operation 1320 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, the memory 340, and / or the positioning component 342, any or all of which can be considered means for performing this operation.

[0209] At 1330, the UE obtains, from the second cell, a second downlink timing and a second RSRP measurement while in the RRC non-connected state based on the first downlink reference timing having changed by more than a threshold, where the second RSRP measurement is a second reference RSRP for the RSRP change calculation. In an aspect, the operation 1330 can be performed by the one or more WWAN transceivers 310, the one or more processors 332, the memory 340, and / or the positioning component 342, any or all of which can be considered means for performing this operation.

[0210] As should be appreciated, a technical advantage of the method 1300 is enabling the UE to autonomously adjust the reference RSRP when adjusting the effective TA.

[0211] In the above detailed description, different features were grouped into examples. This manner of disclosure should not be understood as showing that the example clauses have more features than are explicitly recited in each clause. Rather, the various aspects of the disclosure can include fewer than all features of an individually disclosed example clause. Accordingly, the following clauses should be considered as being incorporated into the description, wherein each clause itself can stand as a separate example. Although each dependent clause can refer to a particular combination of features in the clause to which this dependent clause refers, aspects of that dependent clause are not limited to the specific combination. It is to be understood that other example clauses can also include a combination of aspects from a dependent clause and any other dependent or independent clause or a combination of any features with other dependent or independent clauses. The various aspects disclosed herein expressly include these combinations unless it is explicitly expressed or can be readily inferred that a specific 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.

[0212] Various implementation examples are described in the following numbered clauses:

[0213] Clause 1. A method of wireless communication performed by a user equipment (UE), the method comprising: obtaining, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determining that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtaining, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0214] Clause 2. The method of clause 1, wherein the first cell is: a most recent serving cell, or a most recent camped cell.

[0215] Clause 3. The method of any of clauses 1-2, wherein the second cell is a new camped cell.

[0216] Clause 4. The method of any of clauses 1-3, further comprising: maintaining a first valid timing advance (TA) and the first reference RSRP based on the first downlink reference timing changing less than the threshold while in the RRC non-connected state.

[0217] Clause 5. The method of clause 4, further comprising: determining a second valid TA based on the first valid TA and a second downlink reference timing based on the first downlink reference timing having changed more than the threshold, such that a change in uplink timing of the UE is less than a second threshold.

[0218] Clause 6. The method of clause 5, wherein a difference between the second valid TA and the first valid TA is less than or equal to a difference between the second downlink reference timing and the first downlink reference timing.

[0219] Clause 7. The method of any of clauses 5-6, wherein the second threshold: is configured to the UE, or is based on a subcarrier spacing (SCS), numerology, frequency range, frequency band, signal-to-noise ratio (SNR), RSRP level, or any combination thereof.

[0220] Clause 8. The method of any of clauses 1-7, wherein the threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0221] Clause 9. The method of any of clauses 1-8, wherein the RSRP change calculation comprises determining whether an RSRP measurement of a new camped cell is within an RSRP change threshold of a most recent reference RSRP.

[0222] Clause 10. The method of clause 9, wherein the RSRP change threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0223] Clause 11. The method of any of clauses 1-10, wherein a difference between the second reference RSRP and the first reference RSRP is less than or equal to a second threshold.

[0224] Clause 12. The method of clause 11, wherein the second threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0225] Clause 13. The method of any of clauses 1-12, wherein obtaining the first downlink reference timing comprises: measuring a plurality of synchronization signal blocks (SSBs) transmitted by the first cell within a time window, wherein a length of the time window is selected to avoid clock time drift affecting measurement accuracy.

[0226] Clause 14. The method of clause 13, wherein the measurement accuracy is an accuracy of reference signal time difference (RSTD) measurements of the plurality of SSBs.

[0227] Clause 15. The method of any of clauses 1-14, wherein: the first cell and the second cell are a same cell, and the first downlink reference timing is based on a first SSB from the same cell, and the second downlink reference timing is based on a second SSB from the same cell.

[0228] Clause 16. The method of any of clauses 1-15, wherein the second downlink timing and the second RSRP measurement are obtained based on the UE being configured with a configuration of one or more zone-specific sounding reference signal (SRS) resources.

[0229] Clause 17. The method of any of clauses 1-16, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

[0230] Clause 18. 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, individually or in combination, configured to: obtain, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtain, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed by more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0231] Clause 19. The UE of clause 18, wherein the first cell is: a most recent serving cell, or a most recent camped cell.

[0232] Clause 20. The UE of any of clauses 18-19, wherein the second cell is a new camped cell.

[0233] Clause 21. The UE of any of clauses 18-20, wherein the one or more processors are further configured to, individually or in combination: maintain a first valid timing advance (TA) and the first reference RSRP based on the first downlink reference timing changing less than the threshold while in the RRC non-connected state.

[0234] Clause 22. The UE of clause 21, wherein the one or more processors are further configured to, individually or in combination: determine a second valid TA based on the first valid TA and a second downlink reference timing based on the first downlink reference timing having changed more than the threshold, such that a change in uplink timing of the UE is less than a second threshold.

[0235] Clause 23. The UE of clause 22, wherein a difference between the second valid TA and the first valid TA is less than or equal to a difference between the second downlink reference timing and the first downlink reference timing.

[0236] Clause 24. The UE of any of clauses 22-23, wherein the second threshold: is configured to the UE, or is based on a subcarrier spacing (SCS), numerology, frequency range, frequency band, signal-to-noise ratio (SNR), RSRP level, or any combination thereof.

[0237] Clause 25. The UE of any of clauses 18-24, wherein the threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0238] Clause 26. The UE of any of clauses 18-25, wherein the RSRP change calculation includes determining whether a RSRP measurement of a new camped cell is within a RSRP change threshold of a most recent reference RSRP.

[0239] Clause 27. The UE of clause 26, wherein the RSRP change threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0240] Clause 28. The UE of any of clauses 18-27, wherein a difference between the second reference RSRP and the first reference RSRP is less than or equal to a second threshold.

[0241] Clause 29. The UE of clause 28, wherein the second threshold: is configured to the UE, or is based on a SCS, a numerology, a frequency range, a frequency band, an SNR, an RSRP level, or any combination thereof.

[0242] Clause 30. The UE of any of clauses 18-29, wherein the one or more processors configured to obtain the first downlink reference timing comprises the one or more processors individually or in combination being configured to: measure a plurality of synchronization signal blocks (SSBs) transmitted by the first cell within a time window, wherein a length of the time window is selected to avoid clock time drift affecting measurement accuracy.

[0243] Clause 31. The UE of clause 30, wherein the measurement accuracy is an accuracy of reference signal time difference (RSTD) measurements of the plurality of SSBs.

[0244] Clause 32. The UE of any of clauses 18-31, wherein: the first cell and the second cell are a same cell, and the first downlink reference timing is based on a first SSB from the same cell and the second downlink reference timing is based on a second SSB from the same cell.

[0245] Clause 33. The UE of any of clauses 18-32, wherein the second downlink timing and the second RSRP measurement are obtained based on the UE being configured with a configuration of one or more zone-specific sounding reference signal (SRS) resources.

[0246] Clause 34. The UE of any of clauses 18-33, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

[0247] Clause 35. A user equipment (UE), comprising: means for obtaining, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; means for determining that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and means for obtaining, from the second cell while in the RRC non-connected state, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed by more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0248] Clause 36. The UE of clause 35, wherein the first cell is: a most recent serving cell, or a most recent camped cell.

[0249] Clause 37. The UE of any of clauses 35 to 36, wherein the second cell is a new camped cell.

[0250] Clause 38. The UE of any of clauses 35 to 37, further comprising: means for maintaining a first valid timing advance (TA) and the first reference RSRP based on the first downlink reference timing changing less than the threshold while in the RRC non-connected state.

[0251] Clause 39. The UE of clause 38, further comprising: means for determining a second valid TA based on the first valid TA and a second downlink reference timing based on the first downlink reference timing having changed more than the threshold, such that a change in uplink timing of the UE is less than a second threshold.

[0252] Clause 40. The UE of clause 39, wherein a difference between the second valid TA and the first valid TA is less than or equal to a difference between the second downlink reference timing and the first downlink reference timing.

[0253] Clause 41. The UE of any of clauses 39 to 40, wherein the second threshold: is configured to the UE, or is based on a subcarrier spacing (SCS), numerology, frequency range, frequency band, signal-to-noise ratio (SNR), RSRP level, or any combination thereof.

[0254] Clause 42. The UE of any of clauses 35 to 41, wherein the threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0255] Clause 43. The UE of any of clauses 35 to 42, wherein the RSRP change calculation comprises determining whether a RSRP measurement of a new camped cell is within a RSRP change threshold of a most recent reference RSRP.

[0256] Clause 44. The UE of clause 43, wherein the RSRP change threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0257] Clause 45. The UE of any of clauses 35 to 44, wherein a difference between the second reference RSRP and the first reference RSRP is less than or equal to a second threshold.

[0258] Clause 46. The UE of clause 45, wherein the second threshold: is configured to the UE, or is based on a SCS, a numerology, a frequency range, a frequency band, an SNR, an RSRP level, or any combination thereof.

[0259] Clause 47. The UE of any of clauses 35-46, wherein the means for obtaining the first downlink reference timing comprises means for measuring a plurality of synchronization signal blocks (SSBs) transmitted by the first cell within a time window, wherein a length of the time window is selected to avoid clock time drift affecting measurement accuracy.

[0260] Clause 48. The UE of clause 47, wherein the measurement accuracy is an accuracy of reference signal time difference (RSTD) measurements of the plurality of SSBs.

[0261] Clause 49. The UE of any of clauses 35-48, wherein: the first cell and the second cell are a same cell, and the first downlink reference timing is based on a first SSB from the same cell, and a second downlink reference timing is based on a second SSB from the same cell.

[0262] Clause 50. The UE of any of clauses 35-49, wherein the second downlink timing and the second RSRP measurement are obtained based on the UE being configured with a configuration of one or more zone-specific sounding reference signal (SRS) resources.

[0263] Clause 51. The UE of any of clauses 35-50, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

[0264] Clause 52. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: obtain, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine, based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state, that the first downlink reference timing has changed; and while in the RRC non-connected state, obtain, from the second cell, a second downlink timing and a second RSRP measurement based on the first downlink reference timing having changed by more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

[0265] Clause 53. The non-transitory computer-readable medium of clause 52, wherein the first cell is: a last serving cell, or a last camped cell.

[0266] Clause 54. The non-transitory computer-readable medium of any of clauses 52 to 53, wherein the second cell is a new camped cell.

[0267] Clause 55. The non-transitory computer-readable medium of any of clauses 52 to 54, further comprising computer-executable instructions that, when executed by the UE, cause the UE to: maintain a first valid timing advance (TA) and the first reference RSRP based on the first downlink reference timing changing less than the threshold while in the RRC non-connected state.

[0268] Clause 56. The non-transitory computer-readable medium of clause 55, further comprising computer-executable instructions that, when executed by the UE, cause the UE to: determine a second valid TA based on the first valid TA and a second downlink reference timing such that a change in uplink timing of the UE is less than a second threshold based on the first downlink reference timing having changed more than the threshold.

[0269] Clause 57. The non-transitory computer-readable medium of clause 56, wherein a difference between the second valid TA and the first valid TA is less than or equal to a difference between the second downlink reference timing and the first downlink reference timing.

[0270] Clause 58. The non-transitory computer-readable medium of any of clauses 56 to 57, wherein the second threshold: is configured to the UE, or is based on a subcarrier spacing (SCS), numerology, frequency range, frequency band, signal-to-noise ratio (SNR), RSRP level, or any combination thereof.

[0271] Clause 59. The non-transitory computer-readable medium of any of clauses 52 to 58, wherein the threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

[0272] Clause 60. The non-transitory computer-readable medium of any of clauses 52 to 59, wherein the RSRP change calculation comprises determining whether an RSRP measurement of a new camped cell is within an RSRP change threshold of a last reference RSRP.

[0273] Clause 61. The non-transitory computer-readable medium of clause 60, wherein the RSRP change threshold: is configured to the UE, or is based on a SCS, a numerology, a frequency range, a frequency band, an SNR, an RSRP level, or any combination thereof.

[0274] Clause 62. The non-transitory computer-readable medium of any of clauses 52-61, wherein a difference between the second reference RSRP and the first reference RSRP is less than or equal to a second threshold.

[0275] Clause 63. The non-transitory computer-readable medium of clause 62, wherein the second threshold: is configured to the UE, or is based on a SCS, a numerology, a frequency range, a frequency band, an SNR, an RSRP level, or any combination thereof.

[0276] Clause 64. The non-transitory computer-readable medium of any of clauses 52-63, wherein the computer-executable instructions that, when executed by the UE, cause the UE to obtain the first downlink reference timing comprise computer-executable instructions that, when executed by the UE, cause the UE to: measure a plurality of synchronization signal blocks (SSBs) transmitted by the first cell within a time window, wherein a length of the time window is selected to avoid clock time drift affecting measurement accuracy.

[0277] Clause 65. The non-transitory computer-readable medium of clause 64, wherein the measurement accuracy is an accuracy of reference signal time difference (RSTD) measurements of the plurality of SSBs.

[0278] Clause 66. The non-transitory computer-readable medium of any of clauses 52-65, wherein: the first cell and the second cell are a same cell, and the first downlink reference timing is based on a first SSB from the same cell and the second downlink reference timing is based on a second SSB from the same cell.

[0279] Clause 67. The non-transitory computer-readable medium of any of clauses 52-66, wherein the second downlink timing and the second RSRP measurement are obtained based on the UE being configured with a configuration of one or more zone-specific sounding reference signal (SRS) resources.

[0280] Clause 68. The non-transitory computer-readable medium of any of clauses 52-67, wherein the RRC non-connected state comprises: an RRC inactive state, or an RRC idle state.

[0281] 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.

[0282] Further, those skilled in the art will appreciate that the various illustrative 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 illustrative 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.

[0283] 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.

[0284] 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.

[0285] 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.

[0286] 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 certain features can be described or claimed in particular combinations, each combination should be considered as having been separately claimed. Additionally, it should be noted that the terms "comprises," "comprising," "includes," "including," and the like can be used herein in reference to elements, components, and / or steps of a method or process that will be present therein, but not exclude the presence of one or more other elements, components, and / or steps not expressly listed or encompassed by a process or method. Furthermore, as used herein, the terms "has," "have," "having," "include," "including," or the like are intended to be interpreted as "including" (i.e., one or more elements, components, and / or steps), not as "consisting of' or "consisting essentially of' (i.e., one element, component, and / or step). Additionally, as used herein, the term "or" is intended to be interpreted as an inclusive "or" (i.e., the term "or" means "and / or"), unless otherwise explicitly noted. Furthermore, as used herein, the term "a" is intended to be interpreted as "one or more" (i.e., the term "a" means "one or more"), unless otherwise explicitly noted. Additionally, as used herein, the term "about" is intended to be interpreted broadly and to encompass the recited value and any reasonable approximation thereof. Additionally, as used herein, the term "based on" is intended to be interpreted broadly and to encompass the recited value and any reasonable approximation thereof. Additionally, as used herein, the term "based on" is intended to be interpreted broadly and to encompass the recited value and any reasonable approximation thereof.

Claims

1. A user equipment (UE), the 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, individually or in combination, configured to: obtain a first downlink reference timing and a first reference signal received power (RSRP) measurement from a first cell, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtain a second downlink timing and a second RSRP measurement from the second cell while in the RRC non-connected state based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

2. The UE of claim 1, wherein the first cell is: a most recent serving cell, or a most recent camped cell.

3. The UE of claim 1, wherein the second cell is a new camped cell.

4. The UE of claim 1, wherein the one or more processors, individually or in combination, are further configured to: maintain a first valid timing advance (TA) and the first reference RSRP while in the RRC non-connected state based on the first downlink reference timing changing less than the threshold.

5. The UE of claim 4, wherein the one or more processors, individually or in combination, are further configured to: determine a second valid TA based on the first valid TA and a second downlink reference timing such that a change in uplink timing of the UE is less than a second threshold based on the first downlink reference timing having changed more than the threshold.

6. The UE of claim 5, wherein a difference between the second valid TA and the first valid TA is less than or equal to a difference between the second downlink reference timing and the first downlink reference timing.

7. The UE of claim 5, wherein the second threshold: is configured to the UE, or is based on a subcarrier spacing (SCS), numerology, frequency range, frequency band, signal-to-noise ratio (SNR), RSRP level, or any combination thereof.

8. The UE of claim 1, wherein the threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

9. The UE of claim 1, wherein the RSRP change calculation comprises determining whether a RSRP measurement of a new camped cell is within a RSRP change threshold of a most recent reference RSRP.

10. The UE of claim 9, wherein the RSRP change threshold: is configured to the UE, or is based on a SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof. based on SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

11. The UE of claim 1, wherein a difference between the second reference RSRP and the first reference RSRP is less than or equal to a second threshold.

12. The UE of claim 11, wherein the second threshold: is configured to the UE, or is based on SCS, numerology, frequency range, frequency band, SNR, RSRP level, or any combination thereof.

13. The UE of claim 1, wherein the one or more processors, to obtain the first downlink reference timing, are individually or collectively configured to: measure a plurality of synchronization signal blocks (SSBs) transmitted by the first cell within a time window, wherein a length of the time window is selected to avoid clock time drift affecting measurement accuracy.

14. The UE of claim 13, wherein the measurement accuracy is an accuracy of a reference signal time difference (RSTD) measurement of the plurality of SSBs.

15. The UE of claim 1, wherein: the first cell and the second cell are a same cell, and the first downlink reference timing is based on a first SSB from the same cell and a second downlink reference timing is based on a second SSB from the same cell.

16. The UE of claim 1, wherein the second downlink timing and the second RSRP measurement are obtained based on the UE being configured with a configuration of one or more zone-specific sounding reference signal (SRS) resources.

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

18. A method of wireless communication performed by a user equipment (UE), the method comprising: obtaining, from a first cell, a first downlink reference timing and a first reference signal received power (RSRP) measurement, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determining, based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state, that the first downlink reference timing has changed; and obtaining, from the second cell, a second downlink timing and a second RSRP measurement while in the RRC non-connected state, based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

19. The method of claim 18, further comprising: maintaining, while in the RRC non-connected state, a first valid timing advance (TA) and the first reference RSRP based on the first downlink reference timing changing less than the threshold.

20. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: obtain a first downlink reference timing and a first reference signal received power (RSRP) measurement from a first cell, wherein the first RSRP measurement is a first reference RSRP for a RSRP change calculation; determine that the first downlink reference timing has changed based on a cell reselection from the first cell to a second cell performed while in a radio resource control (RRC) non-connected state; and obtain a second downlink timing and a second RSRP measurement from the second cell while in the RRC non-connected state based on the first downlink reference timing having changed more than a threshold, wherein the second RSRP measurement is a second reference RSRP for the RSRP change calculation.

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