Sidelink Positioning Reference Signal Sequence

Abstract

Techniques for wireless communications are disclosed. In one aspect, a PRS sequence is determined based in part on a sidelink zone in which a transmitting UE is located. A receiving UE may perform a blind search based on PRS sequence(s) associated with its own sidelink zone and / or neighboring sidelink zones. In other aspects, measurement reports may be conveyed to a position estimation entity along with positioning measurements associated with the respective PRS sequences, which may then be correlated to the respective transmitting UE at the position estimation entity to facilitate position estimation of the target UE.

Description

[Technical field]

[0001] Field of Disclosure Aspects of the present disclosure generally relate to wireless communications. [Background technology]

[0002] 2. Description of Related Art

[0002] Wireless communication systems have evolved through various generations, including first-generation analog wireless telephone service (1G), second-generation (2G) digital wireless telephone service (including interim 2.5G and 2.75G networks), third-generation (3G) high-speed data, Internet-enabled wireless service, and fourth-generation (4G) service (e.g., Long Term Evolution (LTE) or WiMax). Currently, many different types of wireless communication systems are in use, including cellular systems 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), Global System for Mobile communications (GSM), etc.

[0003]

[0003] The fifth-generation (5G) wireless standard, called New Radio (NR), requires higher data rates, a larger number of connections, and better coverage, among other improvements. According to the Next Generation Mobile Network Alliance, the 5G standard is designed to provide data rates of tens of megabits per second to tens of thousands of users, providing 1 gigabit per second to a few dozen workers on an office floor. To support large-scale deployment of sensors, hundreds of thousands of simultaneous connections must be supported. Therefore, the spectral efficiency of 5G mobile communications should be significantly increased compared to the current 4G standard. Furthermore, signaling efficiency must be increased and latency significantly reduced compared to the current standard.

[0004]

[0004] In particular, vehicle-to-everything (V2X) communication technologies are being implemented to leverage the increased data rates and reduced latency of 5G to support autonomous driving applications, such as wireless communications between vehicles, between vehicles and roadside infrastructure, between vehicles and pedestrians, etc. Summary of the Invention

[0005]

[0005] The following provides a simplified summary relating to one or more aspects disclosed herein. Therefore, the following summary should not be considered as an extensive overview of all contemplated aspects, nor should the following summary be considered as identifying key or critical elements of all contemplated aspects or as defining the scope relating to any particular aspect. Thus, the sole purpose of the following summary is to present certain concepts of one or more aspects of the mechanisms disclosed herein in a simplified form prior to the detailed description presented below.

[0006]

[0006] In one aspect, a method for operating a user equipment (UE) includes determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identifying one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone, and transmitting a sidelink PRS in accordance with the identified PRS sequence.

[0007] In some aspects, the sidelink PRS is transmitted on a common sidelink frequency layer.

[0008]

[0008] In some aspects, the multiple reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, and the method further includes determining one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0009]

[0009] In some aspects, the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with the sidelink zone in which the UE is located.

[0010]

[0010] In some aspects, the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof.

[0011]

[0011] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0012]

[0012] In some aspects, the identifying includes monitoring one or more sidelink PRS associated with one or more PRS sequences from one or more other UEs, and selecting, based on the monitoring, a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence.

[0013]

[0013] In some aspects, the method includes detecting a PRS sequence collision associated with a transmitted sidelink PRS and selecting a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0014] In some aspects, the identified PRS sequence is assigned to the UE by an external entity.

[0015]

[0015] In one aspect, a method for operating a user equipment (UE) includes determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identifying one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, and performing a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0016]

[0016] In some aspects, the blind search is performed on a common sidelink frequency layer.

[0017] In some aspects, a blind search is performed for multiple reserved PRS resource pools associated with the sidelink assisted position estimation procedure.

[0018]

[0018] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0019]

[0019] In some aspects, the set of sidelink zones includes the sidelink zone in which the UE is located and neighbor nodes of the sidelink zone in which the UE is located.

[0020]

[0020] In some aspects, the method includes transmitting a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via a blind search.

[0021] In some aspects, a blind search is performed only on one or more identified PRS sequences.

[0022] In some aspects, a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0023]

[0023] In one aspect, a method for operating a user equipment (UE) includes performing one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRSs being associated with a respective PRS sequence, and transmitting a measurement report to a position estimation entity including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0024] In some aspects, one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0025]

[0025] In some aspects, the method includes transmitting a sidelink PRS as part of a sidelink-assisted position estimation procedure and transmitting a second indication of a PRS sequence associated with the transmitted sidelink PRS to a position estimation entity.

[0026]

[0026] In some aspects, the sidelink assisted position estimation procedure is associated with a plurality of reserved PRS resource pools, and one or more sidelink PRSs are each received on one of the plurality of reserved PRS resource pools.

[0027]

[0027] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0028]

[0028] In one aspect, a method for operating a position estimation entity includes receiving a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink-assisted position estimation procedure, the measurement report including a first indication of PRS sequences for each of the positioning measurements; receiving a second indication of PRS sequences to be used by a set of user equipment (UE) for transmitting the sidelink PRS; correlating the positioning measurements with the set of UEs by matching the first indication to the second indication; and determining a position estimate for a target UE based on the correlation.

[0029]

[0029] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0030] In some aspects, the location estimate is determined via a round trip time (RTT) location estimation scheme.

[0031]

[0031] In one 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, wherein the at least one processor is configured to: determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones; identify one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone; and transmit, via the at least one transceiver, a sidelink PRS in accordance with the identified PRS sequence.

[0032] In some aspects, the sidelink PRS is transmitted on a common sidelink frequency layer.

[0033]

[0033] In some aspects, multiple reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, and the at least one processor is further configured to determine one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0034]

[0034] In some aspects, the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with the sidelink zone in which the UE is located.

[0035]

[0035] In some aspects, the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof.

[0036]

[0036] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0037]

[0037] In some aspects, the identification includes monitoring one or more sidelink PRSs associated with one or more PRS sequences from one or more other UEs, and based on the monitoring, selecting a respective PRS sequence not being used by the one or more other UEs as the identified PRS sequence.

[0038]

[0038] In some aspects, the at least one processor is further configured to detect a PRS sequence collision associated with the transmitted sidelink PRS and select a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0039] In some aspects, the identified PRS sequence is assigned to the UE by an external entity.

[0040]

[0040] In one 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, wherein the at least one processor is configured to: determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones; identify one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone; and perform a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0041]

[0041] In some aspects, the blind search is performed on a common sidelink frequency layer.

[0042] In some aspects, a blind search is performed for multiple reserved PRS resource pools associated with the sidelink assisted position estimation procedure.

[0043]

[0043] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0044]

[0044] In some aspects, the set of sidelink zones includes the sidelink zone in which the UE is located and neighbor nodes of the sidelink zone in which the UE is located.

[0045]

[0045] In some aspects, the at least one processor is further configured to transmit, via the at least one transceiver, a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via a blind search.

[0046] In some aspects, a blind search is performed only on one or more identified PRS sequences.

[0047] In some aspects, a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0048]

[0048] In one 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, wherein the at least one processor is configured to perform one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRS being associated with a respective PRS sequence, and to transmit via the at least one transceiver a measurement report to a position estimation entity including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0049] In some aspects, one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0050]

[0050] In some aspects, the at least one processor is further configured to transmit, via the at least one transceiver, a sidelink PRS as part of a sidelink assisted position estimation procedure, and to transmit, via the at least one transceiver, a second indication of a PRS sequence associated with the transmitted sidelink PRS to the position estimation entity.

[0051]

[0051] In some aspects, the sidelink assisted position estimation procedure is associated with a plurality of reserved PRS resource pools, and one or more sidelink PRSs are each received on one of the plurality of reserved PRS resource pools.

[0052]

[0052] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0053]

[0053] In one aspect, the location estimation entity includes a memory, at least one transceiver, and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to receive, via the at least one transceiver, a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink assisted location estimation procedure, where the measurement report includes a first indication of a PRS sequence for each of the positioning measurements, receive, via the at least one transceiver, a second indication of a PRS sequence to be used by a set of user equipments (UEs) for transmitting the sidelink PRS, and correlate the positioning measurements with the set of UEs by matching the first indication to the second indication, and determine a location estimate for a target UE based on the correlation.

[0054]

[0054] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0055] In some aspects, the location estimate is determined via a round trip time (RTT) location estimation scheme.

[0056]

[0056] In one aspect, a user equipment (UE) includes means for determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, means for identifying one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone, and means for transmitting a sidelink PRS in accordance with the identified PRS sequence.

[0057]

[0057] In some aspects, the sidelink PRS is transmitted on a common sidelink frequency layer.

[0058]

[0058] In some aspects, a plurality of reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, and the method further comprises means for determining one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0059]

[0059] In some aspects, the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with the sidelink zone in which the UE is located.

[0060]

[0060] In some aspects, the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof.

[0061]

[0061] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0062]

[0062] In some aspects, the identifying means includes means for monitoring one or more sidelink PRS associated with one or more PRS sequences from one or more other UEs, and means for selecting, based on the monitoring, a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence.

[0063]

[0063] In some aspects, the method includes means for detecting a PRS sequence collision associated with a transmitted sidelink PRS and means for selecting a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0064] In some aspects, the identified PRS sequence is assigned to the UE by an external entity.

[0065]

[0065] In one aspect, a user equipment (UE) includes means for determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, means for identifying one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, and means for performing a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0066]

[0066] In some aspects, the blind search is performed on a common sidelink frequency layer.

[0067]

[0067] In some aspects, a blind search is performed for multiple reserved PRS resource pools associated with the sidelink assisted position estimation procedure.

[0068]

[0068] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0069]

[0069] In some aspects, the set of sidelink zones includes the sidelink zone in which the UE is located and neighbor nodes of the sidelink zone in which the UE is located.

[0070]

[0070] In some aspects, the method includes a means for transmitting a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via a blind search.

[0071] In some aspects, a blind search is performed only on one or more identified PRS sequences.

[0072]

[0072] In some aspects, a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0073]

[0073] In one aspect, a user equipment (UE) includes means for performing one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRSs being associated with a respective PRS sequence, and means for transmitting a measurement report to a position estimation entity including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0074]

[0074] In some aspects, one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0075]

[0075] In some aspects, the method includes means for transmitting a sidelink PRS as part of a sidelink-assisted position estimation procedure and means for transmitting a second indication of a PRS sequence associated with the transmitted sidelink PRS to a position estimation entity.

[0076]

[0076] In some aspects, the sidelink assisted position estimation procedure is associated with multiple reserved PRS resource pools, and one or more sidelink PRSs are each received on one of the multiple reserved PRS resource pools.

[0077]

[0077] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0078]

[0078] In one aspect, the position estimation entity includes means for receiving a measurement report, the measurement report being positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink assisted position estimation procedure, the measurement report including a first indication of PRS sequences for each of the positioning measurements, means for receiving a second indication of PRS sequences to be used by a set of user equipments (UEs) for transmitting the sidelink PRS, means for correlating the positioning measurements with the set of UEs by matching the first indication to the second indication, and means for determining a position estimate for a target UE based on the correlation.

[0079]

[0079] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0080]

[0080] In some aspects, the location estimate is determined via a round trip time (RTT) location estimation scheme.

[0081]

[0081] In one aspect, a non-transitory computer-readable medium stores computer-executable instructions that, when executed by a user equipment (UE), cause the UE to determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identify one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone, and transmit a sidelink PRS in accordance with the identified PRS sequence.

[0082]

[0082] In some aspects, the sidelink PRS is transmitted on a common sidelink frequency layer.

[0083]

[0083] In some aspects, multiple reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, and the instructions further cause the UE to determine one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0084]

[0084] In some aspects, the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with the sidelink zone in which the UE is located.

[0085]

[0085] In some aspects, the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof.

[0086]

[0086] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0087]

[0087] In some aspects, the identifying includes monitoring one or more sidelink PRS associated with one or more PRS sequences from one or more other UEs, and selecting, based on the monitoring, a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence.

[0088]

[0088] In some aspects, the one or more instructions further cause the UE to detect a PRS sequence collision associated with the transmitted sidelink PRS and select a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0089] In some aspects, the identified PRS sequence is assigned to the UE by an external entity.

[0090]

[0090] In one aspect, a non-transitory computer-readable medium stores computer-executable instructions that, when executed by a user equipment (UE), cause the UE to determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identify one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, and perform a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0091]

[0091] In some aspects, the blind search is performed on a common sidelink frequency layer.

[0092]

[0092] In some aspects, a blind search is performed for multiple reserved PRS resource pools associated with the sidelink assisted position estimation procedure.

[0093]

[0093] In some aspects, the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0094]

[0094] In some aspects, the set of sidelink zones includes the sidelink zone in which the UE is located and neighbor nodes of the sidelink zone in which the UE is located.

[0095]

[0095] In some aspects, the instructions further cause the UE to transmit a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via the blind search.

[0096]

[0096] In some aspects, a blind search is performed only on one or more identified PRS sequences.

[0097]

[0097] In some aspects, a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0098]

[0098] In one aspect, a non-transitory computer-readable medium stores computer-executable instructions that, when executed by a UE, cause the UE to perform one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRSs being associated with a respective PRS sequence, and to send a measurement report to a position estimation entity including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0099]

[0099] In some aspects, one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0100]

[0100] In some aspects, the one or more instructions further cause the UE to transmit a sidelink PRS as part of the sidelink assisted position estimation procedure and to transmit a second indication of a PRS sequence associated with the transmitted sidelink PRS to the position estimation entity.

[0101]

[0101] In some aspects, the sidelink assisted position estimation procedure is associated with a plurality of reserved PRS resource pools, and one or more sidelink PRSs are each received on one of the plurality of reserved PRS resource pools.

[0102]

[0102] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0103]

[0103] In one aspect, a non-transitory computer-readable medium stores computer-executable instructions that, when executed by a position estimation entity, cause the position estimation entity to receive a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink assisted position estimation procedure, where the measurement report includes a first indication of PRS sequences for each of the positioning measurements, receive a second indication of PRS sequences to be used by a set of user equipment (UE) for transmitting the sidelink PRS, correlate the positioning measurements with the set of UEs by matching the first indication to the second indication, and determine a position estimate for a target UE based on the correlation.

[0104]

[0104] In some aspects, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0105]

[0105] In some aspects, the location estimate is determined via a round trip time (RTT) location estimation scheme.

[0106]

[0106] Other objects and advantages associated with the embodiments disclosed herein will become apparent to those skilled in the art based on the accompanying drawings and detailed description. [Brief description of the drawings]

[0107]

[0107] The accompanying drawings are presented to aid in the explanation of various aspects of the present disclosure and are provided only to illustrate the aspects and not to limit the aspects. [Figure 1]

[0108] 1 illustrates an example wireless communication system according to an aspect of the present disclosure. [Figure 2A]

[0109] 1 illustrates an exemplary wireless network structure in accordance with an aspect of the present disclosure. [Figure 2B] 1 illustrates an exemplary wireless network structure in accordance with an aspect of the present disclosure. [Figure 3A]

[0110] 1 is a simplified block diagram of several sample aspects of components that may be employed in a user equipment (UE), a base station, and a network entity, respectively, and configured to support communications as taught herein. [Figure 3B] 1 is a simplified block diagram of several sample aspects of components that may be employed in a user equipment (UE), a base station, and a network entity, respectively, and configured to support communications as taught herein. [Figure 3C] 1 is a simplified block diagram of several sample aspects of components that may be employed in a user equipment (UE), a base station, and a network entity, respectively, and configured to support communications as taught herein. [Figure 4]

[0111] FIG. 2 is a block diagram illustrating various components of an exemplary user equipment (UE) in accordance with aspects of the present disclosure. [Diagram 5]

[0112] 1 illustrates an example of a wireless communication system supporting unicast sidelink establishment in accordance with an aspect of the present disclosure. [Figure 6A]

[0113] 1 illustrates an example of a TDD sidelink (PC5) resource configuration according to one embodiment of the present disclosure. [Figure 6B]

[0114] 1 illustrates an SCI-based resource reservation scheme according to one embodiment of the present disclosure. [Figure 7]

[0115] 1 illustrates examples of various positioning methods according to aspects of the present disclosure. [Figure 8]

[0116] 1 illustrates a sidelink communication scheduling (or resource allocation) scheme according to an aspect of the present disclosure. [Figure 9]

[0117] 1 illustrates an example wireless communication system in which a vehicle user equipment (V-UE) is exchanging ranging signals with a roadside unit (RSU) and another V-UE, in accordance with an aspect of the present disclosure. [Figure 10]

[0118] 1 illustrates another sidelink positioning scheme according to an aspect of the present disclosure. [Figure 11]

[0119] 1 illustrates another UE distribution scenario for sidelink positioning, in accordance with an aspect of the present disclosure. [Figure 12]

[0120] 1 illustrates an example process for wireless communication according to an aspect of the present disclosure. [Figure 13]

[0121] 1 illustrates a sidelink-assisted position estimation scheme according to an aspect of the present disclosure. [Figure 14] 1 illustrates a sidelink-assisted position estimation scheme according to an aspect of the present disclosure. [Figure 15] 1 illustrates a sidelink-assisted position estimation scheme according to an aspect of the present disclosure. [Figure 16] 1 illustrates a sidelink-assisted position estimation scheme according to an aspect of the present disclosure. [Figure 17]

[0122] 1 illustrates zones according to the World Geodetic System 84 (WSG84) model based on reference longitude and latitude coordinates (0,0), according to one embodiment of the present disclosure. [Figure 18]

[0123] 1 illustrates a sidelink zone topology according to one aspect of the present disclosure. [Figure 19]

[0124] 1 illustrates a SL anchor UE reconfiguration scheme according to one aspect of the present disclosure. [Figure 20]

[0125] 1 illustrates an SL zone configuration according to one embodiment of the present disclosure. [Figure 21]

[0126] 1 illustrates an example process for wireless communication according to an aspect of the present disclosure. [Figure 22]

[0127] 1 illustrates an example process for wireless communication according to an aspect of the present disclosure. [Figure 23]

[0128] 1 illustrates a PRS resource pool configuration according to one aspect of the present disclosure. [Figure 24]

[0129] 1 illustrates an SL zone configuration according to an embodiment of the present disclosure. [Diagram 25]

[0130] 1 illustrates an example process for wireless communication according to an aspect of the present disclosure. [Figure 26]

[0131] 1 illustrates an example process for wireless communication according to an aspect of the present disclosure. [Figure 27]

[0132] 1 illustrates a PRS resource pool configuration according to one aspect of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0108]

[0133] Aspects of the present disclosure are provided in the following description and associated drawings directed to various examples provided for illustrative purposes. Alternative aspects may be devised without departing from the scope of the present disclosure. Additionally, well-known elements of the present disclosure will not be described in detail or will be omitted so as not to obscure the relevant details of the present disclosure.

[0109]

[0134] 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. Similarly, the term "aspects of the present disclosure" does not require that all aspects of the present disclosure include the discussed feature, advantage or mode of operation.

[0110]

[0135] Those skilled in the art will appreciate that the information and signals described below may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the following description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof, depending in part on the specific application, in part on the desired design, in part on the corresponding technology, etc.

[0111]

[0136] Further, many aspects are described in terms of sequences of actions to be performed by, for example, elements of a computing device. It will be appreciated that various actions described herein may be performed by specific circuitry (e.g., an application specific integrated circuit (ASIC)), by program instructions executed by one or more processors, or a combination of both. Additionally, a sequence of actions described herein may be considered to be fully embodied in any form of non-transitory computer-readable storage medium storing a corresponding set of computer instructions that, when executed, cause or instruct an associated processor of a device to perform the functionality described herein. Thus, various aspects of the present disclosure may be embodied in a number of different forms, all of which are contemplated to be within the scope of the claimed subject matter. In addition, for each of the aspects described herein, the corresponding form of any such aspect may be described herein, for example, as "logic configured to" perform the described actions.

[0112]

[0137] The terms "user equipment" (UE), "vehicle UE" (V-UE), "pedestrian user equipment (UE)" (P-UE), and "base station" as used herein are not intended to be specific or otherwise limited to any particular radio access technology (RAT) unless otherwise specified. In general, a UE may be any wireless communication device (e.g., a vehicle-mounted computer, a vehicle navigation device, a mobile phone, a router, a tablet computer, a laptop computer, an asset positioning device, a wearable (e.g., a smart watch, a smart glass, an augmented reality (AR) / virtual reality (VR) headset, etc.), a vehicle (e.g., a car, a motorcycle, a bicycle, etc.), an Internet of Things (IoT) device, etc.) used by a user to communicate over a wireless communication network. A UE may be mobile or stationary (e.g., at a given time) and may communicate with a radio access network (RAN). As used herein, the term "UE" may be referred to interchangeably as a "mobile device," "access terminal" or "AT," "client device," "wireless device," "subscriber device," "subscriber terminal," "subscriber station," "user terminal" or UT, "mobile terminal," "mobile station," or variations thereof.

[0113]

[0138] A V-UE is a type of UE and may be any in-vehicle wireless communication device, such as a navigation system, a warning system, a heads-up display (HUD), an on-board computer, an in-vehicle infotainment system, an automated driving system (ADS), an advanced driver assistance system (ADAS), etc. Alternatively, a V-UE may be a portable wireless communication device (e.g., a cell phone, a tablet computer, etc.) carried by the driver of the vehicle or a passenger in the vehicle. The term "V-UE" may refer to an in-vehicle wireless communication device or the vehicle itself, depending on the context. A P-UE is a type of UE and may be a portable wireless communication device carried by a pedestrian (i.e., a user not driving or riding in the vehicle). In general, a UE can communicate with a core network via a RAN, through which the UE can be connected to external networks such as the Internet and to other UEs. Of course, other mechanisms for a UE to connect to the core network and / or the Internet are possible, such as via a wired access network, a wireless local area network (WLAN) network (e.g., based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11, etc.), etc.

[0114]

[0139] A base station may operate according to one of several RATs in communication with UEs depending on the network in which the base station is deployed and may alternatively be referred to as an access point (AP), network node, Node B, evolved Node B (eNB), next generation eNB (ng-eNB), New Radio (NR) Node B (also referred to as gNB or gNode B), etc. A base station may be used primarily to support wireless access by UEs, including supporting data, voice, and / or signaling connections for supported UEs. In some systems, a base station may provide only edge node signaling functionality, while in other systems, a base station may provide additional control and / or network management functionality. A communication link through which a UE may send signals to a base station is referred to as an uplink (UL) channel (e.g., reverse traffic channel, reverse control channel, access channel, etc.). The communication links through which a base station can send signals to a UE are called downlink (DL) or forward link channels (e.g., paging channels, control channels, broadcast channels, forward traffic channels, etc.). As used herein, the term traffic channel (TCH) can refer to either a UL / reverse traffic channel or a DL / forward traffic channel.

[0115]

[0140] The term "base station" may refer to a single physical transmission-reception point (TRP) or multiple physical TRPs that may or may not be collocated. For example, when the term "base station" refers to a single physical TRP, the physical TRP may be an antenna of the base station, corresponding to a cell (or several cell sectors) of the base station. When the term "base station" refers to multiple collocated physical TRPs, the physical TRP may be an array of antennas of the base station (e.g., as in the case of a multiple-input multiple-output (MIMO) system or when the base station employs beamforming). When the term "base station" refers to multiple non-collocated physical TRPs, the physical TRP may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transport medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, non-co-located physical TRPs may be serving base stations that receive measurement reports from the UE and neighboring base stations whose reference radio frequency (RF) signals the UE is measuring. Since a TRP is a point from which a base station transmits and receives wireless signals, as used herein, references to transmission from or reception at a base station should be understood as referring to a particular TRP of the base station.

[0116]

[0141] In some implementations that support positioning of UEs, a base station may not support wireless access by the UE (e.g., may not support data, voice, and / or signaling connections for the UE), but instead may transmit reference RF signals to the UE to be measured by the UE and / or may receive and measure signals transmitted by the UE. Such a base station may be referred to as a positioning beacon (e.g., when it transmits RF signals to the UE) and / or a location measurement unit (e.g., when it receives and measures RF signals from the UE).

[0117]

[0142] An "RF signal" includes electromagnetic waves of a given frequency that transport information through space between a transmitter and a receiver. As used herein, a transmitter may transmit a single "RF signal" or multiple "RF signals" to a receiver. However, the receiver may receive multiple "RF signals" corresponding to each transmitted RF signal due to the propagation characteristics of RF signals through a multipath channel. The same transmitted RF signal on different paths between a transmitter and a receiver may be referred to as a "multipath" RF signal. As used herein, an RF signal may also be referred to as a "wireless signal" or simply a "signal" when it is clear from the context that the term "signal" refers to a wireless signal or an RF signal.

[0118]

[0143] 1 illustrates an example wireless communication system 100 according to an aspect of the disclosure. The wireless communication system 100 (sometimes referred to as a wireless wide area network (WWAN)) may include various base stations 102 (labeled "BS") and various UEs 104. The base stations 102 may include macrocell base stations (high-power cellular base stations) and / or small cell base stations (low-power cellular base stations). In an aspect, the macrocell base stations 102 may include eNBs and / or ng-eNBs where the wireless communication system 100 supports an LTE network, or gNBs where the wireless communication system 100 supports an NR network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, etc.

[0119]

[0144] The base stations 102 may collectively form a RAN and may interface with a core network 174 (e.g., evolved packet core (EPC) or 5G core (5GC)) through backhaul links 122 and to one or more location servers 172 (e.g., a location management function (LMF) or a secure user plane location (SUPL) location platform (SLP)) through the core network 174. The location server(s) 172 may be part of the core network 174 or may be external to the core network 174. In addition to other functions, the base stations 102 may perform functions related to one or more of forwarding 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, non-access stratum (NAS) message distribution, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment tracing, RAN information management (RIM), paging, positioning, and delivery of alert messages. The base stations 102 may communicate with each other directly or indirectly (e.g., through EPC / 5GC) via backhaul links 134, which may be wired or wireless.

[0120]

[0145] The base stations 102 may wirelessly communicate with the UEs 104. Each of the base stations 102 may provide communication coverage to a respective geographic coverage area 110. In an aspect, one or more cells may be supported by the base stations 102 in each geographic coverage area 110. A "cell" is a logical communication entity used for communication with a base station (e.g., over some frequency resources, referred to as a carrier frequency, component carrier, carrier, band, etc.) and may be associated with an identifier (e.g., a physical cell identifier (PCI), an enhanced cell identifier (ECI), a virtual cell identifier (VCI), a cell global identifier (CGI), etc.) to distinguish cells operating over the same or different carrier frequencies. In some cases, different cells may be configured according to different protocol types (e.g., machine-type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access for different types of UEs. Because cells are supported by a particular base station, the term "cell" may refer to either or both of the logical communication entity supporting the cell and the base station, depending on the context. In some cases, the term "cell" may also refer to the geographic coverage area (e.g., sector) of a base station, so long as a carrier frequency can be detected and used for communication within some portion of the geographic coverage area 110.

[0121]

[0146] The geographic coverage areas 110 of neighboring macrocell base stations 102 may overlap partially (e.g., in handover regions) and some of the geographic coverage areas 110 may be substantially overlapped by larger geographic coverage areas 110. For example, a small cell base station 102' (labeled "SC" instead of "small cell") may have a geographic coverage area 110' that significantly overlaps with the geographic coverage area 110 of one or more macrocell base stations 102. A network that includes both small cell base stations and macrocell base stations may be known as a heterogeneous network. A heterogeneous network may also include home eNBs (HeNBs), which may serve closed groups known as closed subscriber groups (CSGs).

[0122]

[0147] The communication link 120 between the base station 102 and the UE 104 may include uplink (also referred to as reverse link) transmissions from the UE 104 to the base station 102, and / or downlink (DL) (also referred to as forward link) transmissions from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna techniques, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may be through one or more carrier frequencies. The allocation of carriers may be asymmetric with respect to the downlink and uplink (e.g., more or fewer carriers may be allocated for the downlink than for the uplink).

[0123]

[0148] The wireless communication system 100 may further include a wireless local area network (WLAN) access point (AP) 150 in communication with a WLAN station (STA) 152 over a communication link 154 in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in the unlicensed frequency spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) or listen before talk (LBT) procedure before communicating to determine if a channel is available.

[0124]

[0149] The small cell base station 102' may operate in a licensed and / or unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell base station 102' may utilize LTE or NR technology and use the same 5 GHz unlicensed frequency spectrum used by the WLAN AP 150. A small cell base station 102' employing LTE / 5G in an unlicensed frequency spectrum may extend coverage to and / or increase capacity of an access network. NR in an unlicensed spectrum may be referred to as NR-U. LTE in an unlicensed spectrum may be referred to as LTE-U, licensed assisted access (LAA), or MulteFire.

[0125]

[0150] The wireless communication system 100 may further include a mmW base station 180 that may operate at millimeter wave (mmW) and / or sub-mmW frequencies while communicating with the UE 182. Extremely high frequency (EHF) is a portion of RF in the electromagnetic spectrum. EHF ranges from 30 GHz to 300 GHz and has a wavelength between 1 and 10 millimeters. Radio waves in this band may be referred to as millimeter waves. Sub-mmW may extend down to frequencies of 3 GHz with wavelengths of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz and is also referred to as centimeter waves. Communications using the mmW / sub-mmW radio frequency bands have high path losses and relatively short distances. The mmW base station 180 and the UE 182 may utilize beamforming (transmit and / or receive) over the mmW communication link 184 to compensate for the extremely large path losses and short distances. It will be further appreciated that in alternative configurations, one or more base stations 102 may also transmit using mmW or quasi-mmW and beamforming. Thus, it will be appreciated that the above illustrations are merely examples and should not be construed as limiting various aspects disclosed herein.

[0126]

[0151] Transmit beamforming is a technique for focusing an RF signal in a particular direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts it in all directions (omnidirectionally). With transmit beamforming, the network node determines where a given target device (e.g., UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that particular direction, thereby providing a faster and more powerful RF signal (in terms of data rate) to the receiving device(s). To vary the directionality of an RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of one or more transmitters broadcasting the RF signal. For example, the network node can use an array of antennas (also called a "phased array" or "antenna array") that creates beams of RF waves that can be "steered" to point in different directions without actually moving the antennas. In particular, RF current from a transmitter is fed to each antenna with the correct phase relationship so that the radio waves from the separate antennas combine together to enhance radiation in the desired direction while suppressing and canceling radiation in undesirable directions.

[0127]

[0152] A transmit beam may be quasi-co-located, meaning that the transmit beam appears to a receiver (e.g., a UE) to have the same parameters regardless of whether the network node's own transmit antenna is physically co-located or not. In NR, there are four types of quasi-co-location (QCL) relationships. In particular, a QCL relationship of a given type means that certain parameters for a second reference RF signal on a second beam can be derived from information about a source reference RF signal on a source beam. Thus, if the source reference RF signal is QCL type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, average delay, and delay spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of the second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type C, the receiver can use the source reference RF signal to estimate the Doppler shift and average delay of a second reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type D, the receiver can use the source reference RF signal to estimate spatial reception parameters of a second reference RF signal transmitted on the same channel.

[0128]

[0153] In receive beamforming, a receiver uses a receive beam to amplify RF signals detected on a given channel. For example, the receiver can increase the gain setting and / or adjust the phase setting of an array of antennas in a particular direction to amplify (e.g., increase the gain level) RF signals received from that direction. Thus, when a receiver is said to beamform in some direction, it means that the beam gain in that direction is higher than the beam gains along other directions, or that the beam gain in that direction is the highest compared to the beam gains 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 RF signals received from that direction.

[0129]

[0154] The transmit beam and the receive beam may be spatially related. The spatial relationship means that the parameters for the second beam (e.g., transmit beam or receive beam) for the second reference signal may be derived from information about the first beam (e.g., receive beam or transmit beam) for the first reference signal. For example, the UE may use a particular receive beam to receive a reference downlink reference signal (e.g., synchronization signal block (SSB)) from a base station. The UE may then form a transmit beam for sending an uplink reference signal (e.g., sounding reference signal (SRS)) to that base station based on the parameters of the receive beam.

[0130]

[0155] Note that a "downlink" beam can be either a transmit beam or a receive beam, depending on the entity that forms it. For example, if the base station forms a downlink beam to transmit a reference signal to the UE, then the downlink beam is a transmit beam. However, if the UE forms a downlink beam, then it is a receive beam to receive a downlink reference signal. Similarly, an "uplink" beam can be either a transmit beam or a receive beam, depending on the entity that forms it. For example, if the base station forms an uplink beam, then it is an uplink receive beam, and if the UE forms an uplink beam, then it is an uplink transmit beam.

[0131]

[0156] In 5G, the frequency spectrum in which wireless nodes (e.g., base stations 102 / 180, UEs 104 / 182) operate is divided into multiple frequency ranges: FR1 (450 MHz-6000 MHz), FR2 (24250 MHz-52600 MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). The mmW frequency band generally includes the FR2, FR3, and FR4 frequency ranges. Thus, the terms "mmW" and "FR2" or "FR3" or "FR4" may generally be used interchangeably.

[0132]

[0157] In a multi-carrier system such as 5G, one of the carrier frequencies is called the "primary carrier" or "anchor carrier" or "primary serving cell" or "PCell" and the remaining carrier frequencies are called the "secondary carrier" or "secondary serving cell" or "SCell". In carrier aggregation, the anchor carrier is a carrier operating on the primary frequency (e.g., FR1) utilized by the UE 104 / 182 and on the cell in which the UE 104 / 182 either performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection re-establishment procedure. The primary carrier carries all common control channels and UE-specific control channels and may (but is not always) be a carrier among licensed frequencies. The secondary carrier is a carrier operating on a second frequency (e.g., FR2) that may be configured once an RRC connection is established between the UE 104 and the anchor carrier and may be used to provide additional radio resources. In some cases, the secondary carrier may be a carrier in unlicensed frequencies. Since both the primary uplink carrier and the primary downlink carrier are typically UE specific, the secondary carrier may contain only the necessary signaling information and signals, e.g., the signaling information and signals that are UE specific may not be present in the secondary carrier. This means that different UEs 104 / 182 in a cell may have different downlink primary carriers. The same applies to the uplink primary carrier. The network may change the primary carrier of any UE 104 / 182 at any time. This is done, for example, to distribute the load on different carriers. Since a "serving cell" (whether PCell or SCell) corresponds to a carrier frequency / component carrier over which several base stations are communicating, terms such as "cell", "serving cell", "component carrier", "carrier frequency", etc. may be used interchangeably.

[0133]

[0158] For example, still referring to FIG. 1, one of the frequencies utilized by the macrocell base station 102 may be an anchor carrier (or "PCell"), and the other frequencies utilized by the macrocell base station 102 and / or the mmW base station 180 may be secondary carriers ("SCells"). Simultaneous transmission and / or reception of multiple carriers allows the UE 104 / 182 to significantly increase its data transmission and / or data reception rates. For example, two aggregated 20 MHz carriers in a multi-carrier system would theoretically lead to a two-fold increase in data rate (i.e., 40 MHz) compared to the data rate achieved by a single 20 MHz carrier.

[0134]

[0159] In the example of FIG. 1, any of the illustrated UEs (shown in FIG. 1 as a single UE 104 for simplicity) may receive signals 124 from one or more Earth-orbiting space vehicles (SVs) 112 (e.g., satellites). In one aspect, the SVs 112 may be part of a satellite positioning system that the UEs 104 may use as an independent source of location information. A satellite positioning system typically includes a system of transmitters (e.g., SVs 112) positioned to 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. Although typically located within the SVs 112, transmitters may sometimes be located on ground-based control stations, base stations 102, and / or other UEs 104. The UE 104 may include one or more dedicated receivers specifically designed to receive the signals 124 from the SV 112 to derive geolocation information.

[0135]

[0160] In a satellite positioning system, the use of the signals 124 may be augmented by various satellite-based augmentation systems (SBAS) that may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems. For example, the SBAS may include an augmentation system or systems that provide integrity information, differential corrections, and the like, such as the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multi-functional Satellite Augmentation System (MSAS), the Global Positioning System (GPS)-aided Geo-augmented Navigation, or the GPS and Geo Augmented Navigation System (GAGAN). Thus, as used herein, a satellite positioning system may include any combination of one or more global and / or regional navigation satellites associated with one or more such satellite positioning systems.

[0136]

[0161] In one aspect, the SV 112 may additionally or alternatively be part of one or more non-terrestrial networks (NTNs). In an NTN, the SV 112 is connected to an earth station (also called a ground station, NTN gateway, or gateway), which in turn is connected to an element in a 5G network, such as a modified base station 102 (without a terrestrial antenna) or a network node in a 5G network. This element will then 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 devices. In this way, the UE 104 may receive communication signals (e.g., signal 124) from the SV 112 instead of or in addition to communication signals from the terrestrial base station 102.

[0137]

[0162] In particular, vehicle-to-everything (V2X) communication technology is being implemented to leverage NR's increased data rates and reduced latency to support intelligent transportation systems (ITS) applications such as wireless communications between vehicles (vehicle-to-vehicle, V2V), between vehicles and roadside infrastructure (vehicle-to-infrastructure, V2I), and between vehicles and pedestrians (vehicle-to-pedestrian, V2P). The goal is for vehicles to be able to sense the environment around them and communicate that information to other vehicles, infrastructure, and personal mobile devices. Such vehicular communications will enable safety, mobility, and environmental improvements that current technologies cannot provide. When fully implemented, the technology is expected to reduce unimpeded vehicle collisions by 80%.

[0138]

[0163] Still referring to FIG. 1 , the wireless communication system 100 may include multiple V-UEs 160 that may communicate with the base station 102 over communication link 120 (e.g., using a Uu interface). The V-UEs 160 may also communicate directly with each other over wireless sidelink 162, with roadside access points 164 (also referred to as “roadside units”) over wireless sidelink 166, or with the UE 104 over wireless sidelink 168. Wireless sidelink (or simply “sidelink”) is an adaptation of the core cellular (e.g., LTE, NR) standards that allows direct communication between two or more UEs without the communications having to go through a base station. Sidelink communications may be unicast or multicast and may be used for device-to-device (D2D) medium sharing, V2V communications, V2X communications (e.g., cellular V2X (cV2X) communications, enhanced V2X (eV2X) communications, etc.), emergency rescue applications, etc. One or more of a group of V-UEs 160 utilizing sidelink communications may be within the geographic coverage area 110 of the base station 102. Other V-UEs 160 in such a group may be outside the geographic coverage area 110 of the base station 102 or may not otherwise be able to receive transmissions from the base station 102. In some cases, a group of V-UEs 160 communicating via sidelink communications may utilize a one-to-many (1:M) system, in which each V-UE 160 transmits to all other V-UEs 160 in the group. In some cases, the base station 102 facilitates the scheduling of resources for sidelink communications. In other cases, sidelink communications are performed between the V-UEs 160 without the involvement of the base station 102.

[0139]

[0164] In one aspect, the sidelinks 162, 166, 168 may operate over a target wireless communications medium, which may be shared with other vehicular and / or infrastructure access points, as well as other wireless communications between other RATs. The "medium" may consist of one or more time, frequency, and / or spatial communications resources (e.g., encompassing one or more channels across one or more carriers) associated with wireless communications between one or more transmitter / receiver pairs.

[0140]

[0165] In one aspect, the sidelinks 162, 166, 168 may be cV2X links. The first generation of cV2X is standardized in LTE, and the next generation is expected to be defined in NR. cV2X is a cellular technology that also enables device-to-device communication. In the United States and Europe, cV2X is expected to operate in licensed ITS bands in the sub-6 GHz. Other countries may allocate other bands. Thus, as a specific example, the target medium utilized by the sidelinks 162, 166, 168 may correspond to at least a portion of the sub-6 GHz licensed ITS frequency band. However, the present disclosure is not limited to this frequency band or cellular technology.

[0141]

[0166] In one aspect, the sidelinks 162, 166, 168 may be dedicated short-range communications (DSRC) links. DSRC is a one-way or two-way, short- to medium-range wireless communications protocol using the wireless access for vehicular environments (WAVE) protocol, also referred to as IEEE 802.11p, for V2V, V2I, and V2P communications. IEEE 802.11p is an approved amendment to the IEEE 802.11 standard, which operates in the United States in the licensed ITS band at 5.9 GHz (5.85-5.925 GHz). In Europe, IEEE 802.11p operates in the ITS G5A band (5.875-5.905 MHz). Other countries may allocate other bands. The V2V communications briefly described above are typically conducted on the Safety Channel, a 10 MHz channel dedicated for safety purposes in the United States. The remainder of the DSRC band (total bandwidth of 75 MHz) is intended for other services targeted to drivers, such as road enforcement, toll collection, automated parking, etc. Thus, as a specific example, the medium of interest utilized by the sidelinks 162, 166, 168 may correspond to at least a portion of the 5.9 GHz licensed ITS frequency band.

[0142]

[0167] Alternatively, the medium of interest may correspond to at least a portion of an unlicensed frequency band shared among various RATs. Although different licensed frequency bands have been reserved for some communication systems (e.g., by government agencies such as the Federal Communications Commission (FCC) in the United States), these systems, particularly those employing small cell access points, have recently extended their operation to unlicensed frequency bands, such as the Unlicensed National Information Infrastructure (U-NII) bands used by Wireless Local Area Network (WLAN) technologies, most notably the IEEE 802.11x WLAN technology commonly referred to as "Wi-Fi". Exemplary systems of this type include CDMA systems, TDMA systems, FDMA systems, orthogonal FDMA (OFDMA) systems, single-carrier FDMA (SC-FDMA) systems, and various variants thereof.

[0143]

[0168] Communications between V-UEs 160 are referred to as V2V communications, communications between V-UEs 160 and one or more roadside access points 164 are referred to as V2I communications, and communications between V-UEs 160 and one or more UEs 104 (where UEs 104 are P-UEs) are referred to as V2P communications. V2V communications between V-UEs 160 may include, for example, information about the location, speed, acceleration, heading, and other vehicle data of V-UEs 160. V2I information received at V-UEs 160 from one or more roadside access points 164 may include, for example, road regulations, parking automation information, and the like. V2P communications between V-UEs 160 and UEs 104 may include, for example, information about the location, speed, acceleration, and heading of V-UEs 160, and the location, speed (e.g., if UEs 104 are carried by a user on a bicycle), and heading of UEs 104.

[0144]

[0169] It should be noted that while FIG. 1 illustrates only two of the UEs as V-UEs (V-UE 160), any of the illustrated UEs (e.g., UEs 104, 152, 182, 190) may be V-UEs. Additionally, while only V-UE 160 and a single UE 104 are illustrated as being connected via a sidelink, any of the UEs illustrated in FIG. 1, whether V-UE, P-UE, etc., may be capable of sidelink communication. Additionally, although only UE 182 was described as being capable of beamforming, any of the illustrated UEs, including V-UE 160, may be capable of beamforming. If V-UE 160 is capable of beamforming, V-UE 160 may beamform toward each other (i.e., toward other V-UEs 160), toward roadside access point 164, toward other UEs (e.g., UEs 104, 152, 182, 190), etc. Thus, in some cases, V-UE 160 may utilize beamforming on sidelinks 162, 166, and 168.

[0145]

[0170] The wireless communication system 100 may further include one or more UEs, such as a UE 190, that indirectly connect to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links. In the example of FIG. 1, the UE 190 has a D2D P2P link 192 (e.g., through which the UE 190 may indirectly obtain cellular connectivity) with one of the UEs 104 connected to one of the base stations 102, and a D2D P2P link 194 (through which the UE 190 may indirectly obtain WLAN-based Internet connectivity) with a WLAN STA 152 connected to a WLAN AP 150. In one example, the D2D P2P links 192 and 194 may be supported using any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth, etc. As another example, the D2D P2P links 192 and 194 may be sidelinks such as those described above with respect to the sidelinks 162, 166, and 168.

[0146]

[0171] 2A illustrates an exemplary wireless network structure 200. For example, a 5GC 210 (also referred to as Next Generation Core (NGC)) may be considered functionally as control plane (C-plane) functions 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane (U-plane) functions 212 (e.g., UE gateway functions, access to data networks, IP routing, etc.) that operate cooperatively to form a core network. A user plane interface (NG-U) 213 and a control plane interface (NG-C) 215 connect a gNB 222 to the 5GC 210, specifically to the user plane function 212 and the control plane function 214, respectively. In an additional configuration, a ng-eNB 224 may also be connected to the 5GC 210 via the NG-C 215 to the control plane function 214 and the NG-U 213 to the user plane function 212. Additionally, the ng-eNB 224 may communicate directly with the gNB 222 via a backhaul connection 223. In some configurations, the Next Generation RAN (NG-RAN) 220 may have one or more gNBs 222, while other configurations include one or more of both the ng-eNB 224 and the gNB 222. Either the gNB 222 or the ng-eNB 224 (or both) may communicate with one or more UEs 204 (e.g., any of the UEs described herein).

[0147]

[0172] Another optional aspect may include a location server 230, which may be in communication with the 5GC 210 to provide location assistance to the UE(s) 204. The location servers 230 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each may correspond to a single server. The location servers 230 may be configured to support one or more location services for the UEs 204 that may connect to the location server 230 via the core network 5GC 210 and / or via the Internet (not shown). Furthermore, the location server 230 may be integrated into a component of the core network, or alternatively, may be external to the core network (e.g., a third-party server, such as an original equipment manufacturer (OEM) server or a service server).

[0148]

[0173] 2B illustrates another example wireless network structure 250. A 5GC 260 (which may correspond to 5GC 210 in FIG. 2A) may be considered functionally as control plane functionality provided by an access and mobility management function (AMF) 264 and user plane functionality provided by a user plane function (UPF) 262, which operate cooperatively to form a core network (i.e., 5GC 260). The functions of the AMF 264 include registration management, connection management, reachability management, mobility management, lawful interception, transport for session management (SM) messages between one or more UEs 204 (e.g., any of the UEs described herein) and a session management function (SMF) 266, transparent proxy services for routing SM messages, access authentication and access authorization, transport for short message service (SMS) messages between the UE 204 and a short message service function (SMSF) (not shown), and security anchor functionality (SEAF). The AMF 264 also interacts with an authentication server function (AUSF) (not shown) and the UE 204 to receive intermediate keys established as a result of the UE 204 authentication process. In case of UMTS (universal mobile telecommunications system) subscriber identity module (USIM) based authentication, the AMF 264 retrieves security material from the AUSF. The AMF 264 functions also include security context management (SCM).The SCM receives keys from the SEAF that the SCM uses to derive access network specific keys. The functionality of the AMF 264 also includes location service management for regulated services, transport for location service messages between the UE 204 and the Location Management Function (LMF) 270 (acting as the location server 230), transport for location service messages between the NG-RAN 220 and the LMF 270, EPS bearer identifier allocation for interworking with evolved packet system (EPS), and UE 204 mobility event notification. In addition, the AMF 264 also supports functionality for non-3GPP (Third Generation Partnership Project) access networks.

[0149]

[0174] The functions of the UPF 262 include acting as an anchor point for intra / inter-RAT mobility (when applicable), acting as an external protocol data unit (PDU) session point for interconnection to a data network (not shown), routing and forwarding of packets, 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) processing for the user plane (e.g., uplink / downlink rate enforcement, reflective QoS marking in the downlink), uplink traffic validation (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 sending and forwarding one or more "end markers" to the source RAN node. The UPF 262 may also support forwarding of location service messages on the user plane between the UE 204 and a location server such as the SLP 272.

[0150]

[0175] The functions of the SMF 266 include session management, UE Internet protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering in the UPF 262 to route traffic to the appropriate destination, control of policy enforcement and part of QoS, and downlink data notification. The interface through which the SMF 266 communicates with the AMF 264 is called the N11 interface.

[0151]

[0176] Another optional aspect may include an LMF 270, which may be in communication with the 5GC 260 to provide location assistance to the UE 204. The LMF 270 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each may correspond to a single server. The LMF 270 may be configured to support one or more location services for UEs 204 that may connect to the LMF 270 via a core network, the 5GC 260, and / or via the Internet (not shown). The SLP 272 may support similar functions as the LMF 270, except that the LMF 270 may communicate with the AMF 264, the NG-RAN 220, and the UE 204 on the control plane (e.g., using interfaces and protocols intended to carry signaling messages rather than voice or data), and the SLP 272 may communicate with the UE 204 and external clients (not shown in FIG. 2B ) on the user plane (e.g., using protocols intended to carry voice and / or data, such as transmission control protocol (TCP) and / or IP).

[0152]

[0177] The user plane interface 263 and the control plane interface 265 connect the 5GC 260, and in particular the UPF 262 and the AMF 264, respectively, to one or more gNBs 222 and / or ng-eNBs 224 in the NG-RAN 220. The interface between the gNB(s) 222 and / or ng-eNB(s) 224 and the AMF 264 is referred to as the “N2” interface, and the interface between the gNB(s) 222 and / or ng-eNB(s) 224 and the UPF 262 is referred to as the “N3” interface. The gNB(s) 222 and / or ng_eNB(s) 224 of the NG-RAN 220 may communicate directly with each other via a backhaul connection 223, referred to as the “Xn-C” interface. One or more of the gNBs 222 and / or ng-eNBs 224 may communicate with one or more UEs 204 via a wireless interface referred to as the “Uu” interface.

[0153]

[0178] The functionality of the gNB 222 is divided between a gNB central unit (gNB-CU) 226 and one or more gNB distributed units (gNB-DUs) 228. The interface 232 between the gNB-CU 226 and one or more gNB-DUs 228 is called the "F1" interface. The gNB-CU 226 is a logical node that includes base station functions such as forwarding user data, mobility control, radio access network sharing, positioning, session management, etc., except for those functions that are exclusively allocated to the gNB-DU(s) 228. More specifically, the gNB-CU 226 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 hosts the radio link control (RLC), medium access control (MAC), and physical (PHY) 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. Thus, the UE 204 communicates with the gNB-CU 226 via the RRC, SDAP, and PDCP layers, and with the gNB-DU 228 via the RLC, MAC, and PHY layers.

[0154]

[0179] 3A, 3B, and 3C illustrate some example components (represented by corresponding blocks) that may be incorporated in a UE 302 (which may correspond to any of the UEs described herein), a base station 304 (which may correspond to any of the base stations described herein), and a network entity 306 (which may correspond to or embody any of the network functions described herein, including a location server 230 and an LMF 270, or alternatively, may be independent of the NG-RAN 220 and / or 5GC 210 / 260 infrastructure depicted in FIGS. 2A and 2B, such as a private network) to support file transmission operations taught herein. It will be understood that these components may be implemented in different types of devices in different implementations (e.g., in an ASIC, in a system-on-chip (SoC), etc.). The illustrated components may also be incorporated in other devices in a communication system. For example, other devices in the system may include components similar to the illustrated components to provide similar functionality. Also, a given device may include one or more of the components. For example, a device may contain multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0155]

[0180] The UE 302 and base station 304 each include one or more wireless wide area network (WWAN) transceivers 310 and 350, respectively, and provide means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for ceasing transmission, etc.) over one or more wireless communications networks (not shown), such as an NR network, an LTE network, a GSM network, etc. The WWAN transceivers 310 and 350 may 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., over at least one designated RAT (e.g., NR, LTE, GSM, etc.) over a wireless communications medium of interest (e.g., some set of time / frequency resources in a particular frequency spectrum). The WWAN transceivers 310 and 350 may be variously configured to transmit and encode signals 318 and 358, respectively (e.g., messages, instructions, information, etc.), and conversely, to receive and decode signals 318 and 358, respectively (e.g., messages, instructions, information, pilots, etc.), in accordance with a designated RAT. In particular, the WWAN transceivers 310 and 350 include one or more transmitters 314 and 354, respectively, to transmit and encode signals 318 and 358, respectively, and include one or more receivers 312 and 352, respectively, to receive and decode signals 318 and 358, respectively.

[0156]

[0181] The UE 302 and base station 304 also each, at least in some cases, include one or more short-range wireless transceivers 320 and 360, respectively. The short-range wireless transceivers 320 and 360 may be connected to one or more antennas 326 and 366, respectively, and may provide means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for ceasing transmission, etc.) with other network nodes, such as other UEs, access points, base stations, etc., via at least one designated RAT (e.g., WiFi, LTE-D, Bluetooth, Zigbee, Z-Wave, PC5, dedicated short-range communications (DSRC), wireless access for vehicular environments (WAVE), near-field communication (NFC), etc.) over a wireless communication medium of interest. The short-range wireless transceivers 320 and 360 may be variously configured for transmitting and encoding signals 328 and 368, respectively (e.g., messages, instructions, information, etc.), and conversely, for receiving and decoding signals 328 and 368, respectively (e.g., messages, instructions, information, pilots, etc.), in accordance with a specified RAT. In particular, 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 include 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 may be WiFi transceivers, Bluetooth® transceivers, Zigbee® and / or Z-Wave® transceivers, NFC transceivers, or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceivers.

[0157]

[0182] The UE 302 and base station 304 also, at least in some cases, include satellite signal receivers 330 and 370. The satellite signal receivers 330 and 370 may be connected to one or more antennas 336 and 376, respectively, and may provide a means for receiving and / or measuring satellite positioning / communication signals 338 and 378, respectively. If the satellite signal receivers 330 and 370 are satellite positioning system receivers, the satellite positioning / communication signals 338 and 378 may be global positioning system (GPS) signals, global navigation satellite system (GLONASS) signals, Galileo signals, Beidou signals, Indian Regional Navigation Satellite System (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. If satellite signal receivers 330 and 370 are non-terrestrial network (NTN) receivers, satellite positioning / communications signals 338 and 378 may be communication signals (e.g., carrying control and / or user data) originating from a 5G network. Satellite signal receivers 330 and 370 may comprise any suitable hardware and / or software for receiving and processing satellite positioning / communications signals 338 and 378, respectively. Satellite signal receivers 330 and 370 may request information and actions from other systems as appropriate, and may, at least in some cases, perform calculations to determine the locations of UE 302 and base station 304, respectively, using measurements obtained by any suitable satellite positioning system algorithms.

[0158]

[0183] The base station 304 and the network entity 306 each include one or more network transceivers 380 and 390, respectively, that provide a means for communicating (e.g., a means for transmitting, a means for receiving, etc.) with other network entities (e.g., other base stations 304, other network entities 306). For example, the base station 304 may 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, the network entity 306 may 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 via one or more wired or wireless core network interfaces.

[0159]

[0184] A transceiver may be configured to communicate over a wired or wireless link. A transceiver (whether a wired or wireless transceiver) includes transmitter circuitry (e.g., transmitters 314, 324, 354, 364) and receiver circuitry (e.g., receivers 312, 322, 352, 362). A transceiver may be an integrated device (e.g., embodying transmitter and receiver circuitry in a single device) in some implementations, may comprise separate transmitter and receiver circuitry in some implementations, or may be embodied in other ways in other implementations. The transmitter and receiver circuitry of a wired transceiver (e.g., network transceivers 380 and 390 in some implementations) may be coupled to one or more wired network interface ports. The wireless transmitter circuitry (e.g., transmitters 314, 324, 354, 364) may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as an antenna array, that enable the respective device (e.g., UE 302, base station 304) to perform transmit "beamforming" as described herein. Similarly, the wireless receiver circuitry (e.g., receivers 312, 322, 352, 362) may include or be coupled to multiple antennas (e.g., antenna arrays) that enable the respective device (e.g., UE 302, base station 304) to perform receive beamforming as described herein. In one aspect, the transmitter circuitry and receiver circuitry may share multiple identical antennas (e.g., antennas 316, 326, 356, 366), such that the respective device can only receive or transmit at a given time, but not both at the same time. The wireless transceivers (eg, WWAN transceivers 310 and 350, short-range wireless transceivers 320 and 360) may also include a network listen module (NLM) or the like for performing various measurements.

[0160]

[0185] As used herein, various wireless transceivers (e.g., transceivers 310, 320, 350, and 360, and network transceivers 380 and 390, in some implementations) and wired transceivers (e.g., network transceivers 380 and 390, in some implementations) may be generally characterized as a "transceiver," "at least one transceiver," or "one or more transceivers." Thus, whether a particular transceiver is a wired or wireless transceiver may be inferred from the type of communication being performed. For example, backhaul communications between network devices or servers generally involve signaling via wired transceivers, while wireless communications between a UE (e.g., UE 302) and a base station (e.g., base station 304) generally involve signaling via wireless transceivers.

[0161]

[0186] The UE 302, base station 304, and network entity 306 also include other components that may be used in conjunction with operations as disclosed herein. The UE 302, base station 304, and network entity 306 each include one or more processors 332, 384, and 394, for example, to provide functionality related to wireless communications and to provide other processing functionality. Thus, the processors 332, 384, and 394 may provide processing means, such as determining means, calculating means, receiving means, transmitting means, indicating means, etc. In an aspect, the processors 332, 384, and 394 may include, for example, one or more general purpose processors, multi-core processors, central processing units (CPUs), ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGAs), other programmable logic devices or processing circuitry, or various combinations thereof.

[0162]

[0187] The UE 302, base station 304, and network entity 306 each include memory circuitry implementing memories 340, 386, and 396 (e.g., each including a memory device) for maintaining information (e.g., information indicative of reserved resources, thresholds, parameters, etc.). Thus, the memories 340, 386, and 396 may include means for storing, means for retrieving, means for maintaining, etc. In some cases, the UE 302, base station 304, and network entity 306 each may include PRS sequence components 342, 388, and 398. The PRS sequence components 342, 388, and 398 may be hardware circuits that are part of or coupled to the processors 332, 384, and 394, respectively, which, when executed, cause the UE 302, base station 304, and network entity 306 to perform the functionality described herein. In other aspects, the PRS sequence components 342, 388, and 398 may be external to the processors 332, 384, and 394 (e.g., part of a modem processing system, integrated with another processing system, etc.). Alternatively, the PRS sequence components 342, 388, and 398 may be memory modules stored in the memories 340, 386, and 396, respectively, that when executed by the processors 332, 384, and 394 (or a modem processing system, another processing system, etc.), cause the UE 302, the base station 304, and the network entity 306 to perform the functionality described herein. FIG. 3A illustrates possible locations of the PRS sequence component 342, which may be, for example, part of one or more of the WWAN transceivers 310, the memory 340, the one or more processors 332, or any combination thereof, or may be a stand-alone component. FIG. 3B shows possible locations of a PRS sequence component 388, which may be, for example, part of one or more WWAN transceivers 350, memory 386, one or more processors 384, or any combination thereof, or may be a stand-alone component.FIG. 3C shows possible locations of a PRS sequence component 398, which may be, for example, part of one or more network transceivers 390, memory 396, one or more processors 394, or any combination thereof, or may be a stand-alone component.

[0163]

[0188] The UE 302 may include one or more sensors 344 coupled to the one or more processors 332 to provide a means of sensing or detecting movement and / or orientation information that is independent of movement 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 sensor(s) 344 may include an accelerometer (e.g., a micro-electrical mechanical systems (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. Additionally, the sensor(s) 344 may include multiple different types of devices and combine their outputs to provide movement information. For example, the sensor(s) 344 may use a combination of a multi-axis accelerometer and an orientation sensor to provide the ability to calculate a position in a two-dimensional (2D) and / or three-dimensional (3D) coordinate system.

[0164]

[0189] Additionally, the UE 302 includes a user interface 346 that provides a means for providing instructions (e.g., audio and / or visual instructions) to a user and / or receiving user input (e.g., upon user actuation of a sensing device, such as a keypad, touch screen, microphone, etc.). Although not shown, the base station 304 and the network entity 306 may also include user interfaces.

[0165]

[0190] Turning in more detail to the one or more processors 384, on the downlink, IP packets from the network entity 306 may be provided to the processor 384. The one or more processors 384 may implement functionality for an 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 may provide RRC layer functionality associated with system information (e.g., master information block (MIB), system information block (SIB)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, and broadcasting of measurement configurations for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with forwarding of higher layer PDUs, error correction with automatic repeat request (ARQ), concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation 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.

[0166]

[0191] The transmitter 354 and receiver 352 may implement Layer 1 (L1) functionality associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) encoding / decoding of the transport channel, interleaving, rate matching, mapping onto the physical channel, modulation / demodulation of the physical channel, 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 may then be split into parallel streams. Each stream may then be mapped to an 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 generate a physical channel carrying a time-domain OFDM symbol stream. The OFDM symbol stream is spatially precoded to generate multiple spatial streams. Channel estimates from a channel estimator may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimates may be derived from a reference signal and / or channel condition feedback transmitted by the UE 302. Each spatial stream may then be provided to one or more different antennas 356. The transmitter 354 may modulate an RF carrier with the individual spatial streams for transmission.

[0167]

[0192] At the UE 302, the receiver 312 receives signals through its respective antenna(s) 316. The receiver 312 recovers the information modulated onto the RF carriers and provides the information to 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 may 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 may 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 includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the most likely signal constellation point transmitted by the base station 304. These soft decisions may be based on channel estimates calculated by a channel estimator. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted on the physical channel by the base station 304. The data and control signals are then provided to one or more processors 332 that implement Layer 3 (L3) and Layer 2 (L2) functionality.

[0168]

[0193] In the uplink, the one or more processors 332 provide demultiplexing between transport and logical channels, packet reassembly, decryption, header recovery, and control signal processing to recover IP packets from the core network. The one or more processors 332 are also responsible for error detection.

[0169]

[0194] Similar to the functionality described in connection with downlink transmissions by the base station 304, the one or more processors 332 provide RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality associated with forwarding of upper layer PDUs, error correction via ARQ, concatenation, segmentation, and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via hybrid automatic repeat request (HARQ), priority handling, and logical channel prioritization.

[0170]

[0195] Channel estimates derived by the channel estimator from a reference signal or feedback transmitted by the base station 304 may be used by the transmitter 314 to select an appropriate coding and modulation scheme and to facilitate spatial processing. The spatial streams generated by the transmitter 314 may be provided to different antenna(s) 316. The transmitter 314 may modulate an RF carrier with each spatial stream for transmission.

[0171]

[0196] Uplink transmissions are processed at the base station 304 in a manner similar to that described with respect to the receiver functions at the UE 302. The receiver 352 receives signals through its respective antenna(s) 356. The receiver 352 recovers information modulated onto an RF carrier and provides the information to one or more processors 384.

[0172]

[0197] In the uplink, the one or more processors 384 provide demultiplexing between transport and logical channels, packet reassembly, decryption, header recovery, and control signal processing to recover IP packets from the UE 302. The IP packets from the one or more processors 384 may be provided to a core network. The one or more processors 384 are also responsible for error detection.

[0173]

[0198] For convenience, the UE 302, base station 304, and / or network entity 306 are illustrated in Figures 3A, 3B, and 3C as including various components that may be configured according to various examples described herein. However, it will be understood that the illustrated components may have different functionality in different designs. In particular, various components in Figures 3A-3C are optional in alternative configurations, and various aspects include configurations that may vary due to design choice, cost, device use, or other considerations. For example, in the case of Figure 3A, a particular implementation of the UE 302 may omit the WWAN transceiver(s) 310 (e.g., a wearable device or tablet computer or PC or laptop may have Wi-Fi and / or Bluetooth capabilities without cellular capabilities), or may omit the short-range wireless transceiver(s) 320 (e.g., cellular only, etc.), or may omit the satellite signal receiver 330, or may omit the sensor(s) 344, etc. 3B, a particular implementation of base station 304 may omit WWAN transceiver(s) 350 (e.g., a Wi-Fi "hotspot" access point without cellular capability), or may omit short-range wireless transceiver(s) 360 (e.g., cellular only, etc.), or may omit satellite receiver 370, etc. For brevity, examples of various alternative configurations are not provided herein, but should be readily apparent to one of ordinary skill in the art.

[0174]

[0199] The various components of the UE 302, base station 304, and network entity 306 may be communicatively coupled to one another via data buses 334, 382, ​​and 392, respectively. In an aspect, the data buses 334, 382, ​​and 392 may form or be part of communication interfaces of the UE 302, base station 304, and network entity 306, respectively. For example, when various logical entities are embodied within the same device (e.g., gNB and location server functionality integrated within the same base station 304), the data buses 334, 382, ​​and 392 may provide communication therebetween.

[0175]

[0200] The components of Figures 3A, 3B, and 3C may be implemented in a variety of ways. In some implementations, the components of Figures 3A, 3B, and 3C may be implemented in one or more circuits, such as, for example, one or more processors and / or one or more ASICs (which may include one or more processors), where each circuit may use and / or incorporate at least one memory component for storing information or executable code used by the circuit to provide its functionality. For example, some or all of the functionality represented by blocks 310-346 may be implemented by the processor component(s) and memory component(s) of the UE 302 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Similarly, some or all of the functionality represented by blocks 350-388 may be implemented by the processor component(s) and memory component(s) of the base station 304 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Also, some or all of the functionality represented by blocks 390-398 may be implemented by the processor component(s) and memory component(s) of the network entity 306 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). For simplicity, various operations, acts, and / or functions are described herein as being performed "by the UE," "by the base station," "by the network entity," etc. However, it will be understood that such operations, acts, and / or functions may actually be performed by a particular component or combination of components of the UE 302, base station 304, network entity 306, etc., such as the processors 332, 384, 394, transceivers 310, 320, 350, and 360, memories 340, 386, and 396, and PRS sequence components 342, 388, and 398.

[0176]

[0201] In some designs, the network entity 306 may be implemented as a core network component. In other designs, the network entity 306 may be separate from the network operator or operation of the cellular network infrastructure (e.g., the NG RAN 220 and / or the 5GC 210 / 260). For example, the network entity 306 may be a component of a private network that may be configured to communicate with the UE 302 via the base station 304 or independently of the base station 304 (e.g., via a non-cellular communication link such as WiFi).

[0177]

[0202] 3A may represent a "low tier" UE or a "premium" UE. As described further below, low tier UEs and premium UEs may have the same types of components (e.g., both may have a WWAN transceiver 310, a processing system 332, memory components 340, etc.), but those components may have different degrees of functionality (e.g., increased or decreased performance, more or less capabilities, etc.) depending on whether the UE 302 corresponds to a low tier UE or a premium UE.

[0178]

[0203] UEs may be categorized as low tier UEs (e.g., wearables such as smart watches, glasses, rings, etc.) and premium UEs (e.g., smartphones, tablet computers, laptop computers, etc.). Low tier UEs may alternatively be referred to as reduced capability NR UEs, reduced capability UEs, NR Lite UEs, Lite UEs, NR Super Lite UEs, or Super Lite UEs. Premium UEs may alternatively be referred to as full capability UEs or simply UEs. A low tier UE generally has lower baseband processing capability, fewer antennas (e.g., one receiver antenna as a baseline in FR1 or FR2, optionally two receiver antennas), lower operating bandwidth capability (e.g., 20 MHz without supplemental uplink or carrier aggregation for FR1, or 50 MHz or 100 MHz for FR2), half duplex frequency division duplex (HD-FDD) capability only, smaller HARQ buffer, reduced physical downlink control channel (PDCCH) monitoring, limited modulation (e.g., 64QAM for downlink and 16QAM for uplink), relaxed processing timeline requirements, and / or lower uplink transmit power compared to a premium UE. Different UE tiers may be differentiated by UE category and / or by UE capability. For example, some types of UEs may be assigned a "low tier" classification (e.g., by original equipment manufacturer (OEM), applicable wireless communications standard, etc.) and other types of UEs may be assigned a "premium" classification. Some tier UEs may also report their type (e.g., "low tier" or "premium") to the network. Additionally, some resources and / or channels may be dedicated to some types of UEs.

[0179]

[0204] As can be appreciated, the accuracy of low-tier UE positioning may be limited. For example, low-tier UEs may operate on a reduced bandwidth, such as 5 MHz to 20 MHz, for wearable devices and "relaxed" IoT devices (i.e., IoT devices with relaxed or lower capability parameters, such as lower throughput, relaxed delay requirements, lower energy consumption, etc.), which results in lower positioning accuracy. As another example, the receive processing capability of a low-tier UE may be limited by its lower-cost RF / baseband. Thus, the reliability of measurements and positioning calculations will be reduced. In addition, such low-tier UEs may not be able to receive multiple PRSs from multiple TRPs, further reducing positioning accuracy. As yet another example, the transmit power of a low-tier UE may be reduced, which means that there will be lower quality uplink measurements for low-tier UE positioning.

[0180]

[0205] A premium UE generally has a larger form factor, is more expensive than a low-tier UE, and has more features and capabilities than a low-tier UE. For example, with respect to positioning, a premium UE may operate on the full PRS bandwidth, such as 100 MHz, and measure PRS from more TRPs than a low-tier UE, both of which result in higher positioning accuracy. As another example, the receive processing capability of a premium UE may be higher (e.g., faster) due to its higher-capacity RF / baseband. In addition, the transmit power of a premium UE may be higher than that of a low-tier UE. Thus, the reliability of measurements and positioning calculations will be increased.

[0181]

[0206] FIG. 4 is a block diagram illustrating various components of an exemplary UE 400 according to aspects of the disclosure. In an aspect, the UE 400 may correspond to any of the UEs described herein (e.g., an exemplary implementation of UE 302, etc.). As a specific example, the UE 400 may be a V-UE, such as the V-UE 160 in FIG. 1. For simplicity, the various features and functions illustrated in the block diagram of FIG. 4 are connected together using a common data bus, which is intended to represent that these various features and functions are operatively coupled together. Those skilled in the art will recognize that other connections, mechanisms, features, functions, etc. may be provided and adapted as necessary to operatively couple and configure an actual UE. It is further recognized that one or more of the features or functions illustrated in the example of FIG. 4 may be further subdivided, or two or more of the features or functions illustrated in FIG. 4 may be combined.

[0182]

[0207] The UE 400 may include at least one transceiver 404 coupled to one or more antennas 402, which provides means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for ceasing transmission, etc.) with other network nodes, such as a V-UE (e.g., V-UE 160), an infrastructure access point (e.g., roadside access point 164), a P-UE (e.g., UE 104), a base station (e.g., base station 102), etc., via at least one designated RAT (e.g., cV2X or IEEE 802.11p) over one or more communication links (e.g., communication link 120, sidelinks 162, 166, 168, mmW communication link 184). The at least one transceiver 404 may be variously configured for transmitting and encoding signals (e.g., messages, instructions, information, etc.) and conversely for receiving and decoding signals (e.g., messages, instructions, information, pilots, etc.) in accordance with the designated RAT. In one aspect, the at least one transceiver 404 and the antenna(s) 402 may form a (wireless) communication interface of the UE 400.

[0183]

[0208] A "transceiver," as used herein, may in some implementations include at least one transmitter and at least one receiver in an integrated device (e.g., embodied as transmitter and receiver circuits in a single communications device), in some implementations may comprise separate transmitter and receiver devices, or in other implementations may be embodied in other ways. In one aspect, the transmitter may include or be coupled to multiple antennas, such as an antenna array (e.g., antenna(s) 402), that enable the UE 400 to perform transmit "beamforming," as described herein. Similarly, the receiver may include or be coupled to multiple antennas, such as an antenna array (e.g., antenna(s) 402), that enable the UE 400 to perform receive beamforming, as described herein. In one aspect, the transmitter(s) and receiver(s) may share the same multiple antennas (e.g., antenna(s) 402) such that the UE 400 can only receive or transmit at a given time, rather than both receive and transmit at the same time. In some cases, a transceiver may not provide both transmit and receive functionality. For example, in some designs, a low-function receiver circuit (e.g., a receiver chip or similar circuitry that merely provides low-level sniffing) may be employed to reduce cost when it is not necessary to provide full communication.

[0184]

[0209] The UE 400 may also include a satellite positioning system (SPS) receiver 406. The SPS receiver 406 may be connected to one or more SPS antennas 403 and may provide a means for receiving and / or measuring satellite signals. The SPS receiver 406 may comprise any suitable hardware and / or software for receiving and processing SPS signals, such as Global Positioning System (GPS) signals. The SPS receiver 406 requests information and actions from other systems as appropriate, and performs the calculations necessary to determine the position of the UE 400 using the measurements obtained by any suitable SPS algorithms.

[0185]

[0210] One or more sensors 408 may be coupled to the at least one processor 410 and may provide a means for sensing or detecting information regarding the state and / or environment of the UE 400, such as speed, heading (e.g., compass heading), headlight status, gas mileage, etc. By way of example, the one or more sensors 408 may include a speedometer, a tachometer, an accelerometer (e.g., a micro-electromechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), etc.

[0186]

[0211] The at least one processor 410 may include one or more central processing units (CPUs), microprocessors, microcontrollers, ASICs, processing cores, digital signal processors (DSPs), field programmable gate arrays (FPGAs), etc. that provide processing functionality as well as other computational and control functionality. Thus, the at least one processor 410 may provide means for processing, such as means for determining, means for calculating, means for receiving, means for transmitting, means for indicating, etc. The at least one processor 410 may include any form of logic suitable for performing or causing components of the UE 400 to perform at least the techniques described herein.

[0187]

[0212] The at least one processor 410 may also be coupled to a memory 414 that provides a means for storing (including a means for retrieving, a means for maintaining, etc.) data and software instructions for executing programmed functionality within the UE 400. The memory 414 may be on-board the at least one processor 410 (e.g., within the same integrated circuit (IC) package) and / or the memory 414 may be external to the at least one processor 410 and operatively coupled thereto via a data bus.

[0188]

[0213] The UE 400 may include a user interface 450 providing any suitable interface system, such as a microphone / speaker 452, a keypad 454, and a display 456, to enable user interaction with the UE 400. The microphone / speaker 452 may provide voice communication services with the UE 400. The keypad 454 may comprise any suitable buttons for user input to the UE 400. The display 456 may comprise any suitable display, such as, for example, a backlit liquid crystal display (LCD), and may further include a touch screen display for additional user input modes. The user interface 450 may thus be a means for providing instructions (e.g., audible and / or visual instructions) to a user and / or receiving user input (e.g., via user actuation of a sensing device, such as a keypad, touch screen, microphone, etc.).

[0189]

[0214] In one aspect, the UE 400 may include a sidelink manager 470 coupled to the at least one processor 410. The sidelink manager 470 may be a hardware, software, or firmware component that, when executed, causes the UE 400 to perform the operations described herein. For example, the sidelink manager 470 may be a software module stored in the memory 414 and executable by the at least one processor 410. As another example, the sidelink manager 470 may be a hardware circuit (e.g., an ASIC, a field programmable gate array (FPGA), etc.) within the UE 400.

[0190]

[0215] 5 illustrates an example of a wireless communication system 500 supporting wireless unicast sidelink establishment according to aspects of the disclosure. In some examples, the wireless communication system 500 may implement aspects of the wireless communication systems 100, 200, and 250. The wireless communication system 500 may include a first UE 502 and a second UE 504, which may be examples of any of the UEs described herein. As specific examples, the UEs 502 and 504 may correspond to the V-UE 160 in FIG. 1, the UE 190 and UE 104 in FIG. 1 connected via the D2D P2P link 192, or the UE 204 in FIG. 2A and FIG. 2B.

[0191]

[0216] In the example of Fig. 5, UE 502 may attempt to establish a unicast connection with UE 504 over a sidelink, which may be a V2X sidelink between UE 502 and UE 504. As a specific example, the established sidelink connection may correspond to sidelinks 162 and / or 168 in Fig. 1. The sidelink connection may be established in an omni-directional frequency range (e.g., FR1) and / or a mmW frequency range (e.g., FR2). In some cases, UE 502 may be referred to as an initiating UE that initiates a sidelink connection procedure, and UE 504 may be referred to as a target UE that is targeted for the sidelink connection procedure by the initiating UE.

[0192]

[0217] To establish a unicast connection, access stratum (AS) (a functional layer in the UMTS and LTE protocol stacks, and part of Layer 2, between the RAN and the UE responsible for transporting data over the wireless link and managing radio resources) parameters may be configured and negotiated between the UE 502 and the UE 504. For example, transmission and reception capability matching may be negotiated between the UE 502 and the UE 504. Each UE may have different capabilities (e.g., transmission and reception, 64 quadrature amplitude modulation (QAM), transmit diversity, carrier aggregation (CA), supported communication frequency band(s), etc.). In some cases, different services may be supported at higher layers of the corresponding protocol stacks for the UE 502 and the UE 504. Additionally, a security association may be established between the UE 502 and the UE 504 for the unicast connection. Unicast traffic may benefit from security protection (e.g., integrity protection) at the link level. Security requirements may be different for different wireless communication systems. For example, V2X and Uu systems may have different security requirements (e.g., Uu security does not include confidentiality protection). Additionally, IP configurations (e.g., IP version, addresses, etc.) may be negotiated for unicast connections between UE 502 and UE 504.

[0193]

[0218] In some cases, the UE 504 may create a service announcement (e.g., a service capability message) for transmission over a cellular network (e.g., cV2X) to assist in sidelink connection establishment. Conventionally, the UE 502 may identify and locate candidates for sidelink communication based on a broadcasted basic service message (BSM) that is decrypted by nearby UEs (e.g., the UE 504). The BSM may include location information, security and identification information for the serving UE, as well as vehicle information (e.g., speed, operation, size, etc.). However, in the case of a different wireless communication system (e.g., D2D or V2X communication), the discovery channel may not be configured to allow the UE 502 to detect the BSM(s). Thus, the service announcement (e.g., discovery signal) transmitted by the UE 504 and other nearby UEs may be a higher layer signal and may be broadcast (e.g., in an NR sidelink broadcast). In some cases, the UE 504 may include one or more parameters for itself in the service announcement, including connection parameters and / or capabilities it possesses. The UE 502 may then monitor for and receive the broadcasted service announcements to identify potential UEs for a corresponding sidelink connection. In some cases, the UE 502 may identify potential UEs based on the capabilities that each UE indicates in their respective service announcements.

[0194]

[0219] The service announcement may include information to assist the UE 502 (e.g., or any initiating UE) in identifying the UE (UE 504 in the example of FIG. 5) that is sending the service announcement. For example, the service announcement may include channel information in which the direct communication request may be sent. In some cases, the channel information may be RAT-specific (e.g., specific to LTE or NR) and may include a resource pool in which the UE 502 sends the communication request. Additionally, the service announcement may include a specific destination address (e.g., Layer 2 destination address) for the UE if the destination address is different from the current address (e.g., the address of the streaming provider or the UE sending the service announcement). The service announcement may also include a network layer or transport layer for the UE 502 to send the communication request. For example, the network layer (also referred to as "Layer 3" or "L3") or transport layer (also referred to as "Layer 4" or "L4") may indicate a port number of the application for the UE sending the service announcement. In some cases, IP addressing may not be required if the signaling (e.g., PC5 signaling) directly carries a protocol (e.g., real-time transport protocol (RTP)) or provides a locally generated random protocol. Additionally, the service announcement may include the type of protocol for certificate establishment and QoS related parameters.

[0195]

[0220] After identifying a potential sidelink connection target (UE 504 in the example of FIG. 5), the initiating UE (UE 502 in the example of FIG. 5) may send a connection request 515 to the identified target UE 504. In some cases, the connection request 515 may be a first RRC message (e.g., an "RRCDirectConnectionSetupRequest" message) sent by the UE 502 to request a unicast connection with the UE 504. For example, the unicast connection may utilize a PC5 interface for sidelink, and the connection request 515 may be an RRC Connection Setup Request message. Additionally, the UE 502 may use a sidelink signaling radio bearer 505 to transport the connection request 515.

[0196]

[0221] After receiving the connection request 515, the UE 504 may determine whether to accept or reject the connection request 515. The UE 504 may base this decision on transmit / receive capabilities, the ability to accommodate a unicast connection over the sidelink, the particular service indicated for the unicast connection, the content to be transmitted over the unicast connection, or a combination thereof. For example, if the UE 502 desires to use a first RAT to transmit or receive data, but the UE 504 does not support the first RAT, the UE 504 may reject the connection request 515. Additionally or alternatively, the UE 504 may reject the connection request 515 based on an inability to accommodate a unicast connection over the sidelink due to limited radio resources, scheduling issues, etc. Thus, the UE 504 may transmit an indication of whether the request is accepted or rejected in the connection response 520. Similar to the UE 502 and the connection request 515, the UE 504 may use the sidelink signaling radio bearer 510 to transport a connection response 520. Additionally, the connection response 520 may be a second RRC message sent by the UE 504 in response to the connection request 515 (e.g., an "RRCDirectConnectionResponse" message).

[0197]

[0222] In some cases, the sidelink signaling radio bearers 505 and 510 may be the same sidelink signaling radio bearer or may be separate sidelink signaling radio bearers. Thus, a radio link control (RLC) layer acknowledged mode (AM) may be used for the sidelink signaling radio bearers 505 and 510. UEs supporting unicast connections may listen on a logical channel associated with the sidelink signaling radio bearer. In some cases, the AS layer (i.e., Layer 2) may pass information directly through RRC signaling (e.g., control plane) instead of the V2X layer (e.g., data plane).

[0198]

[0223] If the connection response 520 indicates that the UE 504 accepted the connection request 515, the UE 502 may then send a connection establishment 525 message on the sidelink signaling radio bearer 505 to indicate that the unicast connection setup is complete. In some cases, the connection establishment 525 may be a third RRC message (e.g., an "RRCDirectConnectionSetupComplete" message). Each of the connection request 515, the connection response 520, and the connection establishment 525 may use basic capabilities when in transport from one UE to the other UE to enable each UE to receive and decode the corresponding transmission (e.g., an RRC message).

[0199]

[0224] Additionally, an identifier may be used for each of the connection request 515, the connection response 520, and the connection establishment 525. For example, the identifier may indicate which UE 502 / 504 is sending which message and / or which UE 502 / 504 the message is intended for. For physical (PHY) layer channels, the RRC signaling and any subsequent data transmissions may use the same identifier (e.g., Layer 2 ID). However, for logical channels, the identifiers may be separate for the RRC signaling and for the data transmissions. For example, on logical channels, the RRC signaling and the data transmissions may be treated differently and may have different acknowledgement (ACK) feedback messaging. In some cases, for RRC messaging, a physical layer ACK may be used to ensure that the corresponding message is transmitted and received correctly.

[0200]

[0225] One or more information elements may be included in the connection request 515 and / or connection response 520 for the UE 502 and / or UE 504, respectively, to enable negotiation of corresponding AS layer parameters for the unicast connection. For example, the UE 502 and / or UE 504 may include Packet Data Convergence Protocol (PDCP) parameters in the corresponding unicast connection setup message to set up a PDCP context for the unicast connection. In some cases, the PDCP context may indicate whether PDCP duplication is utilized for the unicast connection. Additionally, the UE 502 and / or UE 504 may include RLC parameters when establishing the unicast connection to set up an RLC context for the unicast connection. For example, the RLC context may indicate whether AM (e.g., a reordering timer (t reordering) is used) or unacknowledged mode (UM) is used for the RLC layer of the unicast communication.

[0201]

[0226] Additionally, the UE 502 and / or UE 504 may include medium access control (MAC) parameters to set up a MAC context for a unicast connection. In some cases, the MAC context may enable a resource selection algorithm, a hybrid automatic repeat request (HARQ) feedback scheme (e.g., ACK or negative ACK (NACK) feedback), parameters for a HARQ feedback scheme, carrier aggregation, or a combination thereof, for the unicast connection. Additionally, the UE 502 and / or UE 504 may include PHY layer parameters when establishing a unicast connection to set up a PHY layer context for the unicast connection. For example, the PHY layer context may indicate a transmission format (unless a transmission profile is included per UE 502 / 504) and a radio resource configuration (e.g., bandwidth part (BWP), numerology, etc.) for the unicast connection. These information elements may be supported for different frequency range configurations (e.g., FR1 and FR2).

[0202]

[0227] In some cases, a security context may also be set for the unicast connection (e.g., after the connection establishment 525 message is sent). Before a security association (e.g., security context) is established between the UE 502 and the UE 504, the sidelink signaling radio bearers 505 and 510 may not be protected. After the security association is established, the sidelink signaling radio bearers 505 and 510 may be protected. Thus, the security context may enable secure data transmission over the unicast connection as well as the sidelink signaling radio bearers 505 and 510. Additionally, IP layer parameters (e.g., link-local IPv4 or IPv6 addresses) may also be negotiated. In some cases, the IP layer parameters may be negotiated by a higher layer control protocol operating after the RRC signaling is established (e.g., the unicast connection is established). As mentioned above, the UE 504 may base its decision whether to accept or reject the connection request 515 for the particular service indicated for the unicast connection and / or the content (e.g., higher layer information) to be transmitted over the unicast connection. The particular service and / or content may also be indicated by higher layer control protocols operating after the RRC signaling is established.

[0203]

[0228] After the unicast connection is established, the UE 502 and the UE 504 may communicate using a unicast connection over a sidelink 530, where sidelink data 535 is transmitted between the two UEs 502 and 504. The sidelink 530 may correspond to the sidelinks 162 and / or 168 of FIG. 1. In some cases, the sidelink data 535 may include RRC messages transmitted between the two UEs 502 and 504. To maintain this unicast connection over the sidelink 530, the UE 502 and / or the UE 504 may transmit keep-alive messages (e.g., "RRC Direct Link Alive" message, fourth RRC message, etc.). In some cases, the keep-alive messages may be triggered (e.g., event-triggered) periodically or on-demand. Thus, the triggering and transmission of the keep-alive messages may be invoked by the UE 502 or by both the UE 502 and the UE 504. Additionally or alternatively, a MAC control element (CE) (e.g., defined over sidelink 530) may be used to monitor the status of the unicast connection on sidelink 530 and maintain the connection. When the unicast connection is no longer needed (e.g., when UE 502 travels far enough away from UE 504), either UE 502 and / or UE 504 may initiate a release procedure to delete the unicast connection over sidelink 530. Thus, no subsequent RRC messages may be transmitted between UE 502 and UE 504 over the unicast connection.

[0204]

[0229] Various physical sidelink channels may be used for sidelink communications and / or RF-EH, including the Physical sidelink control channel (PSCCH), the Physical sidelink shared channel (PSSCH), the Physical sidelink feedback channel (PSFCH), and the Physical sidelink broadcast channel (PSBCH). Various sidelink reference signals may be used for sidelink communications and / or RF-EH, including Demodulation RS (DMRS) for PSCCH, Demodulation RS (DMRS) for PSSCH, Demodulation RS (DMRS) for PSBCH, Channel State Information RS (CSI-RS), Primary synchronization signal (S-PSS), Secondary synchronization signal (S-SSS), and Phase-tracking RS (PTRS) for FR2 only.

[0205]

[0230] In some designs, a slot may include 14 OFDM symbols with resources arranged according to a time division duplex (TDD) resource configuration. In some designs, the sidelink may be configured (e.g., pre-configured or dynamically configured) to occupy less than 14 symbols in a slot. In some designs, the first symbol is repeated on the preceding symbol for automatic gain control (AGC) resolution. In some designs, the subchannel size may be configured (e.g., pre-configured or dynamically configured) in {10, 15, 20, 25, 50, 75, 100} physical resource blocks (PRBs). In some designs, the PSCCH and PSSCH are always transmitted in the same slot.

[0206]

[0231] In some designs, to receive a sidelink packet, the UE performs a blind search in all sidelink subchannels. The number of subchannels is typically small, e.g., 1 to 27 subchannels, so that a blind search of all subchannels is still feasible. In some designs, the PSSCH is

[0207]

number

[0208] In some designs, the PSCCH may occupy up to one subchannel with the lowest subchannel index. In some designs, the first stage SCI, which includes information about the PSSCH bandwidth and resource reservation in future slots, is transmitted in the PSCCH. In some designs, the second stage SCI may be found and decoded after the decoded PSCCH, source ID, and destination ID are used to distinguish whether the packet is for the UE and from which UE it is coming. In some designs, the subchannel size in V2X may be large, e.g., a minimum of 10 RB. In some designs, cellular (C-V2X) requires a blind search of all subchannels, with the UE intending to decode all transmissions.

[0209]

[0232] 6A illustrates an example of a TDD sidelink (PC5) resource configuration 600 according to one aspect of the disclosure. The TDD sidelink (PC5) resource configuration 600 includes 14 OFDM symbols, shown as symbols 0-13. In the TDD sidelink (PC5) resource configuration 600 of FIG. 6A, the PSCCH is allocated to symbols 0-3 (e.g., in a first bandwidth), the PSSCH is allocated to symbols 0-3 and symbols 4-9 (e.g., in a second bandwidth), a gap is defined in symbol 10, the PSFCH is allocated to symbols 11-12, and a gap is defined in symbol 13. The TDD sidelink (PC5) resource configuration 600 is just one example resource configuration and other configurations are possible in other aspects.

[0210]

[0233] Referring to FIG. 6A, for SCI1_0 in PSCCH, the frequency domain resource allocation (FDRA) is

[0211]

number

[0212] For the reservation of bits or three

[0213]

number

[0214] The time domain resource allocation (TDRA) may consist of 5 bits for two reservations or 9 bits for three reservations.

[0215]

[0234] Figure 6B shows an SCI-based resource reservation scheme 650 according to one aspect of the present disclosure. In Figure 6B, a first reservation 652 is defined at slot i, a second reservation 654 is offset from slot i by x slots (slot i + x), where 0 < x ≦ 31, and a third reservation 656 is offset from slot I by y slots (slot i + y), where x < y ≦ 31.

[0216]

[0235] Referring to FIGS. 6A and 6B, in some designs, the PSCCH is (pre-)configured to occupy {10, 12, 15, 20, 25} PRBs limited to a single subchannel. In some designs, the PSCCH duration is (pre-)configured to two or three symbols. In some designs, the subchannel can occupy {10, 15, 20, 25, 50, 75, 100} PRBs. In some designs, the number of subchannels can be 1 to 27 within a resource pool (RP). In some designs, the PSCCH size is fixed for the resource pool (e.g., the PSCCH size can occupy 10% to 100% of one subchannel (the first two or three symbols) depending on the configuration). In some designs, the PSSCH occupies at least one subchannel and includes a second-stage SCI.

[0217]

[0236] NR supports several 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. FIG. 7 illustrates examples of various positioning methods according to aspects of the present disclosure. In an OTDOA or DL-TDOA positioning procedure, illustrated by scenario 710, a UE measures the difference between the times of arrival (ToA) of reference signals (e.g., positioning reference signals (PRS)) received from pairs of base stations, called reference signal time difference (RSTD) or time difference of arrival (TDOA) measurements, and reports them to a positioning entity. More specifically, the UE receives an identifier (ID) of a reference base station (e.g., a serving base station) and multiple non-reference base stations in the assistance data. The UE then measures the RSTD between the reference base station and each of the non-reference base stations. Based on the known locations of the involved base stations and the RSTD measurements, the positioning entity can estimate the location of the UE.

[0218]

[0237] As illustrated by scenario 720, for DL-AoD positioning, the positioning entity uses beam reports from the UE of received signal strength measurements of multiple downlink transmit beams to determine the angle(s) between the UE and the transmitting base station(s). The positioning entity can then estimate the location of the UE based on the determined angle(s) and the known location(s) of the transmitting base station(s).

[0219]

[0238] 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 an uplink reference signal (e.g., Sounding Reference Signal (SRS)) transmitted by the UE. 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 the UE on one or more uplink receive beams. The positioning entity uses the signal strength measurements and the angle(s) of the receive beam(s) to determine the angle(s) between the UE and the base station(s). Based on the determined angle(s) and the known location(s) of the base station(s), the positioning entity can then estimate the location of the UE.

[0220]

[0239] Downlink and uplink based positioning methods include enhanced cell-ID (E-CID) positioning and multi-round-trip-time (RTT) positioning (also called "multi-cell RTT"). In the RTT procedure, an initiator (base station or UE) transmits an RTT measurement signal (e.g., PRS or SRS) to a responder (UE or base station), and the responder transmits an RTT response signal (e.g., SRS or PRS) back to the initiator. The RTT response signal includes the difference between the ToA of the RTT measurement signal and the transmission time of the RTT response signal, called the receive-transmit (Rx-Tx) time difference. The initiator calculates the difference between the transmission time of the RTT measurement signal and the ToA of the RTT response signal, called the transmit-receive (Tx-Rx) time difference. The propagation time (also called "time of flight") between the initiator and the responder can be calculated from the Tx-Rx and Rx-Tx time differences. Based on the propagation time and the known speed of light, the distance between the initiator and responder can be determined. In the case of multi-RTT positioning, as illustrated by scenario 730, the UE performs RTT procedures with multiple base stations to allow its location to be determined based on the known locations of the base stations (e.g., using multilateration). The RTT and multi-RTT methods can be combined with other positioning techniques, such as UL-AoA and DL-AoD, as illustrated by scenario 740, to improve location accuracy.

[0221]

[0240] 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 identities of detected neighboring base stations, estimated timing, and signal strength. The location of the UE is then estimated based on this information and the known location of the base station(s).

[0222]

[0241] To assist the positioning operation, a location server (e.g., location server 230, LMF 270, SLP 272) may provide assistance data to the UE. For example, the assistance data may include an identifier of the base station (or cell / TRP of the base station) from which to measure the reference signal, reference signal configuration parameters (e.g., number of consecutive positioning subframes, periodicity of the positioning subframes, muting sequence, frequency hopping sequence, reference signal identifier, reference signal bandwidth, etc.), and / or other parameters applicable to a particular positioning method. Alternatively, the assistance data may be obtained directly from the base station itself (e.g., in periodically broadcasted overhead messages, etc.). In some cases, the UE may be able to detect neighboring network nodes itself without using the assistance data.

[0223]

[0242] In the case of OTDOA or DL-TDOA positioning procedures, the assistance data may further include an expected RSTD value and an associated uncertainty around the expected RSTD, i.e., a search window. In some cases, the value range for the expected RSTD may be + / - 500 microseconds (μs). In some cases, the value range for the expected RSTD uncertainty may be + / - 32 μs when any of the resources used for the positioning measurements are in FR1. In other cases, the value range for the expected RSTD uncertainty may be + / - 8 μs when all of the resources used for the positioning measurement(s) are in FR2.

[0224]

[0243] A location estimate may be referred to by other names, such as a position estimate, location, position, position fix, fix, etc. A location estimate may be geodetic and comprise coordinates (e.g., latitude, longitude, and possibly altitude), or urban and comprise a street address, postal address, or some other linguistic description of the location. A location estimate may also be defined relative to some other known location, or defined absolutely (e.g., using latitude, longitude, and possibly altitude). A location estimate may include an expected error or uncertainty (e.g., by including an area or volume within which the location is expected to be contained with some specified or default level of confidence).

[0225]

[0244] 8 illustrates a sidelink communication scheduling (or resource allocation) scheme 800 according to an aspect of the disclosure. In some designs, resource allocation in V2X may be implemented via Mode 1, where the gNB allocates Tx resources for sidelink communication over DCI3_0. In other designs, resource allocation in V2X may be implemented via Mode 2, where the transmitting UE autonomously determines resources for sidelink communication. In some designs, the behavior of the receiving UE is the same for both Mode 1 and Mode 2.

[0226]

[0245] Referring to FIG. 8, mode 1 may support dynamic grants (DG), configured grants (CG) type 1, and CG type 2. In some designs, CG type 1 is activated via RRC signaling from the gNB. DCI3_0 is sent by the gNB to the allocated time and frequency resources to indicate the transmission timing. In some designs, the modulation and coding scheme (MCS) MCS is up to the UE within a limit set by the gNB. In mode 2, the transmitting UE performs channel sensing by blind decoding all PSCCH channels to find reserved resources by other sidelink transmissions. The transmitting UE reports available resources to higher layers, and the higher layers decide the resource usage.

[0227]

[0246] In some designs, in the industrial IoT (IIoT), sidelinks can enable direct programmable logical controller (PLC) and sensor / actuator (SA) communication. Wireless PLC is desirable for flexible and simple deployment. In some designs, each PLC controls 20-50 SAs. In some designs, the IIoT requires 10-20 Mbps with low latency 1ms-2ms and ultra-reliability requirements. -6 In some designs, communication over the gNB requires multiple OTAs, which impacts latency and reliability.

[0228]

[0247] IIoT traffic is typically deterministic and has small packet sizes 32 bytes to 256 bytes. Thus, the required bandwidth is low, e.g., 2 RBs may be sufficient in some cases. SA may have constraints on UE capabilities in terms of bandwidth and processing power. Overall bandwidth may be large for IIoT using dedicated frequency bands and / or unlicensed bands. In some designs, SA does not need to detect / monitor all transmissions. In some designs, PSCCH must meet stringent IIoT requirements. IIoT networks may also be associated with challenging RF environments due to blockages and interference.

[0229]

[0248] As mentioned above, the first stage SCI may be included in the PSCCH. The first stage SCI may alternatively be referred to as SCI1-A. In some designs, SCI1-A shall be decoded by the intended RX and other sidelink UEs (especially in mode 2) to enable channel sensing and avoid resource collisions. In some designs, SCI1-A may be configured as follows: Priority 3 bits Frequency resource allocation, bits depending on the number of slot reservations and the number of subchannels Time resource allocation, 5 or 9 bits for 2 or 3 reservations Resource reservation period, bits that depend on the number of allowed periods DM-RS pattern, bits depend on the number of configured patterns SCI2 format, 2 bits Beta offset for SCI2 rate matching, 2 bits DM-RS port, 1 bit indicates 1 or 2 data layers MCS, 5-bit Additional MCS table, 0 bits to 2 bits PSFCH overhead indicator, 0 or 1 bit Reserved bits, bits up to higher layers

[0230]

[0249] As mentioned above, the second stage SCI may be included in the PSSCH. The second stage SCI may alternatively be referred to as SCI2. In some designs, SCI2 is intended to help a receiving UE decode the PSSCH. In some designs, SCI2 may be configured as follows: HARQ ID, a bit that depends on the number of HARQ processes NDI, 1-bit RV-ID, 2 bits Source ID, 8 bits Destination ID (16 bits) HARQ enable / disable, 1 bit SCI2-A only fields: Cast type, 2 bits, broadcast, groupcast, unicast; CSI request, 1 bit SCI2-B dedicated fields (NACK-only groupcast): Zone ID, 12 bits; communication range, 4 bits

[0231]

[0250] In addition to downlink-based, uplink-based, and downlink-and-uplink-based positioning methods, NR supports various sidelink positioning techniques. For example, link-level ranging signals can be used to estimate the distance between a pair of V-UEs or between a V-UE and a roadside unit (RSU), similar to the round-trip time (RTT) positioning procedure.

[0232]

[0251] FIG. 9 illustrates an example wireless communication system 900 in which a V-UE 904 is exchanging ranging signals with an RSU 910 and another V-UE 906 according to an aspect of the disclosure. As illustrated in FIG. 9, wideband (e.g., FR1) ranging signals (e.g., Zadoff Chu sequence) are transmitted by both endpoints (e.g., V-UE 904 and RSU 910, and V-UE 904 and V-UE 906). In an aspect, the ranging signals may be sidelink positioning reference signals (SL-PRS) transmitted by the involved V-UEs 904 and 906 on uplink resources. Upon receiving the ranging signal from a transmitter (e.g., V-UE 904), a receiver (e.g., RSU 910 and / or V-UE 906) responds by sending a ranging signal that includes a measurement of the difference between the reception time of the ranging signal and the transmission time of the response ranging signal, referred to as the receiver receive-transmit (Rx-Tx) time difference measurement.

[0233]

[0252] Upon receiving the reply ranging signal, the transmitter (or other positioning entity) can calculate the RTT between the transmitter and the receiver based on the receiver's Rx-Tx time difference measurement and a measurement of the difference between the transmission time of the first ranging signal and the reception time of the reply ranging signal (referred to as the transmitter's transmit-receive (Tx-Rx) time difference measurement). The transmitter (or other positioning entity) uses the RTT and the speed of light to estimate the distance between the transmitter and the receiver. If one or both of the transmitter and the receiver are beamforming capable, it may also be possible to determine the angle between V-UE 904 and V-UE 906. Additionally, if the receiver provides its Global Positioning System (GPS) location in the reply ranging signal, the transmitter (or other positioning entity) may be able to determine the absolute location of the transmitter as opposed to the relative location of the transmitter with respect to the receiver.

[0234]

[0253] As can be seen, the ranging accuracy improves with the bandwidth of the ranging signal. In particular, a higher bandwidth can better separate different multipaths of the ranging signal.

[0235]

[0254] Note that this positioning procedure assumes that the V-UEs involved are time synchronized (i.e., their system frame time is the same as the other V-UE(s) or has a known offset relative to the other V-UE(s). In addition, while Figure 9 shows two V-UEs, it will be appreciated that they do not have to be V-UEs, but instead may be any other type of UE capable of sidelink communication.

[0236]

[0255] 10 illustrates another sidelink positioning scheme 1000 according to an aspect of the disclosure. In FIG. 10, each positioning scheme includes a target UE (in this case, a VR headset), at least one gNB, and at least one reference UE (e.g., a UE with a known location from a recent positioning fix, where such location generally has a lower variance than a typical error estimate for the UE position).

[0237]

[0256] Referring to Figure 10, scenario 1010 illustrates a UE with a known location improving Uu positioning (e.g., RTT-based or TDOA-based) by providing an extra anchor. Scenario 1020 illustrates positioning (i.e., SL-only based positioning / ranging) for a low-tier UE (e.g., a VR headset) via assistance from a premium UE. Scenario 1030 illustrates a relay or reference UE (with a known location) participating in position estimation for a remote UE (e.g., a VR headset) without UL PRS transmission in Uu. Each of the scenarios 1010-1030 may be generally characterized as an SL-aided positioning scheme.

[0238]

[0257] The SL UE assisting the target UE in estimating its position may affect various aspects associated with SL-assisted positioning, such as power consumption and / or position estimation accuracy.

[0239]

[0258] 11 illustrates another UE distribution scenario 1100 for sidelink positioning according to an aspect of the disclosure. In the UE distribution scenario 1110, a large number of UEs participate in the SL-aided positioning, which is good for position estimation accuracy, but also increases power consumption significantly. In the UE distribution scenario 1120, only two UEs participate in the SL-aided positioning, which is good for power consumption, but also reduces position estimation accuracy. In the UE distribution scenario 1130, there is a reasonable number (i.e., four) of UEs participating in the SL-aided positioning, so power consumption is not too high, and the UEs are also well spaced in sufficient numbers for good position estimation accuracy.

[0240]

[0259] Aspects of the present disclosure are directed to selection of UEs to participate in a sidelink-assisted location estimation procedure of a target UE based at least in part on zone information associated with a group of candidate UEs. Such aspects may provide various technical advantages, such as improved location estimation accuracy and / or lower power consumption (e.g., across various UEs involved in the sidelink-assisted location estimation procedure) by spreading the distribution of participating UEs across zones.

[0241]

[0260] 12 illustrates an example process 1200 for wireless communication according to an aspect of the disclosure. In one aspect, the process 1200 may be performed by a target UE (e.g., a UE for which a position estimate is desired), such as the UE 302.

[0242]

[0261] 12, at 1210, a target UE (e.g., receiver 312 or 322, etc.) receives zone information associated with a plurality of zones, where the zone information indicates, for each of a plurality of candidate UEs for the sidelink-assisted location estimation procedure of the target UE, a zone identifier of a zone in which the respective candidate UE is located. In some designs, the zone information for some or all of the plurality of candidate UEs is broadcast by the respective candidate UE (e.g., in which case the zone information for a particular candidate UE is received directly from the particular candidate UE). In some designs, the broadcasted zone information is transmitted via an SCI (e.g., a first stage SCI such as SCI1-A) of the PSCCH. In other designs, the zone information for some or all of the plurality of candidate UEs is received from different respective UEs (e.g., via a relay or forwarding scheme across a mesh network of UEs) or indirectly from a base station (e.g., a gNB accumulates zone information for various UEs and then broadcasts zone information associated with nearby zones). The zone information may include various information, as described in more detail below. In some designs, the means for performing 1210 receiving the zone information may include the receiver 312 or 322 of the UE 302.

[0243]

[0262] 12 , at 1220, the target UE (e.g., processor(s) 332, PRS sequence component 384, etc.) selects one or more candidate UEs for the sidelink-assisted location estimation procedure based at least in part on the zone information. In some designs, the selection at 1220 may be based on one or more zone-based rules, as described in more detail below. In some designs, the means for performing the selection of zone candidate UE(s) at 1220 may include the processor(s) 332, PRS sequence component 384, etc. of the UE 302.

[0244]

[0263] 12, at 1230, the target UE (e.g., processor(s) 332, transmitter 314 or 314, receiver 312 or 322, etc.) performs a sidelink-assisted location estimation procedure with at least the selected one or more candidate UEs. The sidelink-assisted location estimation procedure may be implemented and performed in various manners (e.g., RTT, multi-RTT or differential RTT or double differential RTT, TDOA based, etc.). In some designs, each reference node associated with the sidelink-assisted location estimation procedure corresponds to one or more selected candidate UEs (e.g., as in the case of the SL-only RTT scheme 1030, as an example). In other designs, at least one reference node associated with the sidelink-assisted location estimation procedure corresponds to a base station (e.g., a hybrid sidelink / gNB positioning scheme, such as 1010 or 1020 in FIG. 10). In some designs, the means for performing the sidelink-assisted position estimation procedure at 1230 may include a processor(s) 332, a transmitter 314 or 314, a receiver 312 or 322 of the UE 302, etc., depending on whether the target UE is transmitting SRS and / or measuring PRS and / or deriving Tx->Rx measurements, or whether the target UE is the position estimation entity (e.g., UE-based position estimation), or whether another UE or network component (e.g., LMF) is the position estimation entity.

[0245]

[0264] 12, in some designs, the zone information further includes an indication of precision for the at least one zone identifier indication, and the selection at 1220 is further based on the indication of precision. In some designs, the indication of precision is implicitly indicated by the zone identifier (e.g., a zone ID associated with a known high interference area may be associated with a low precision level by default). In other designs, the indication of precision is included within an SCI of the PSCCH (e.g., SCI1-A) or a PSSCH (e.g., SCI2). In this case, the indication of precision may be based on dynamic conditions (e.g., if the candidate UE is very close to a boundary to another zone and / or on an orbit toward another zone, the candidate UE may indicate a looser association with the indicated zone, etc.).

[0246]

[0265] With reference to FIG. 12 , in some designs, the mapping of zone identifiers to zones, or instructions on how to derive the mapping, may be predefined, preconfigured (e.g., via RRC or SIB), or received at the target UE from an external entity (e.g., via a gNB or another UE). In some designs, the zone identifiers and their associated zones may be application-driven or based on a group communication services (GCS) protocol or a location service (LCS) protocol. For example, in the case of an indoor factory, a zone ID may be associated with a particular hallway, etc. In some designs, the zone identifiers and associated zone calculations may be implemented at the application layer (e.g., derived independently at each UE, etc.).

[0247]

[0266] 12 , in some designs, the selection is based on one or more zone-based rules. In some designs, the one or more zone-based rules include: removing from selection any candidate UEs within a first threshold distance to the target UE; or Exclude from the selection any candidate UEs in the same zone as the target UE, or removing from selection any candidate UE that is beyond a second threshold distance to the target UE; or removing from the selection any candidate UE in any zone that is beyond a third threshold distance to the respective zone of the target UE; or restricting the selection of candidate UEs in the same zone to less than a first threshold number; or limiting the selection of candidate UEs in zones adjacent to each zone of the target UE to less than a second threshold number; or -Combinations of these.

[0248]

[0267] In some designs, some or all of the above rules may be selectively implemented based on various criteria. For example, if the sidelink-assisted location estimation procedure is based on timing measurements, exclusion of candidate UEs that are too close to the target UE (e.g., within the same zone or within a first threshold distance) may be implemented. However, these nearby candidate UEs may be useful for other types of location estimation that rely on angle-based measurements (e.g., AoD or AoA). In this case, proximity exclusion may be selectively implemented based on the type of positioning scheme (e.g., timing-based or angle-based).

[0249]

[0268] 12, in some designs, the target UE may further determine an RSRP of at least one signal from at least one of the multiple candidate UEs, and the selection at 1220 is further based on the RSRP determination (e.g., thus taking into account zone information, but also RSRP). Thus, the selection at 1220 need not be based solely on zone information.

[0250]

[0269] 12, in some designs, the target UE may further determine a line of sight (LOS) or non-LOS (NLOS) confidence level associated with at least one link to at least one of the multiple candidate UEs, and the selection at 1220 is further based on the LOS or NLOS confidence level determination (e.g., thus considering zone information, but also LOS / NLOS conditions). For example, a candidate UE with a LOS link to the target UE may generally be preferred for selection over a candidate UE with a NLOS link to the target UE. Thus, the selection at 1220 need not be based solely on zone information.

[0251]

[0270] With reference to FIG. 12, as mentioned above, the sidelink assisted position estimation procedure may include a timing measurement procedure (e.g., RTT or multi-RTT or differential RTT or double differential RTT or TDOA, etc.), an angle measurement procedure (e.g., AoA or AoD, etc.), or a combination thereof.

[0252]

[0271] Figure 13 illustrates an example implementation 1300 of the process 1200 of Figure 12 according to one aspect of the disclosure. In Figure 13, a grid is shown, with each box of the grid corresponding to a particular zone associated with a respective zone identifier. Marked circles are shown within the grid to indicate target UEs, selected candidate UEs, and non-selected candidate UEs. As illustrated in Figure 13, the selected candidate UEs are spaced apart with respect to zones and also angularly spaced apart to obtain a reasonable spatial distribution of UEs for the sidelink assisted location estimation procedure.

[0253]

[0272] FIG. 14 illustrates an example implementation 1400 of the process 1200 of FIG. 12 according to one aspect of the disclosure. FIG. 14 is similar to FIG. 13, except that a candidate UE cluster is illustrated at 1402 with a number of nearby zone co-located UEs. In some designs, assisting UEs in the same / similar location (e.g., as in the candidate UE cluster 1402) may provide limited gain (e.g., hence the principle for spacing selected candidate UEs). In some designs, one or a few assisting UEs from the same or adjacent zones may be sufficient for a sidelink-assisted position estimation procedure. In some designs, in a scenario with multiple candidate UEs available for selection, the RSRP may be considered as a second-order factor (as described above), e.g., based on the base RSRP from SCI-1 / SCI-2 and PSSCH. In some designs, the candidate UE's "POS accuracy" information, including synchronization error information, may be taken into account by the target UE, as described above. In some designs, as mentioned above, the selection at 1220 may be further based on a prediction (or confidence level) of the LOS / NLOS (eg, which may be derived from DMRS or other aiding information).

[0254]

[0273] FIG. 15 illustrates an example implementation 1500 of the process 1200 of FIG. 12 according to one aspect of the disclosure. FIG. 15 is similar to FIG. 13 except that a proximity-based exclusion area is illustrated at 1502. In some designs, the ToA for the PRS between nearby UEs may be sub-10 ns. In some designs, the PRS and hardware bandwidth may not "resolve" the ToA below the threshold. For example, the resolvable time between samples may be 1 / SamplingFreq, or 3 m for a 100 MHz sampling rate. In some designs, synchronization errors and other biases may cause errors that exceed the distance between the UEs. In some designs, for a timing-based positioning scheme, nearby UEs may only be useful if the immediately nearby UEs have very good POS accuracy. In some designs, for nearby UEs, sharing POS information over SL may be better than receiving the PRS (e.g., instead of measuring the PRS, simply identify the nearby UE location to gain knowledge that the target UE is very close to its location). As mentioned above, nearby UEs may be useful for other types of location estimation schemes, such as angle-based location estimation schemes.

[0255]

[0274] FIG. 16 illustrates an example implementation 1600 of the process 1200 of FIG. 12 according to one aspect of the disclosure. FIG. 16 is similar to FIG. 13, except that a distance-based exclusion area is illustrated at 1602 with some "distant" UEs. In some designs, PRS from more distant UEs require higher power consumption from both Tx and Rx. Thus, UEs within the distance-based exclusion area 1602 may be considered only in scenarios where closer candidate UEs are not available for selection.

[0256]

[0275] As mentioned above, a geographical region may be divided into multiple zones (alternatively referred to as sidelink zones or SL zones). In some designs, the SL zones may be designed for V2X implementations primarily in outdoor spaces (e.g., the zones may encompass roads along which vehicles travel, parking lots, etc.).

[0257]

[0276] 17 illustrates a zone 1700 according to the World Geodetic System 84 (WSG84) model based on a reference longitude and latitude coordinate (0,0) according to one embodiment of the present disclosure. With reference to FIG. 19, in one example: (x,y) is the distance in meters to (0,0), x1=floor(x / L) mode 64, y1=floor(y / L) mode 64, Zone_ID=y1 * 64+x1, L is the length of the zone defined in sl-ZoneConfig

[0258]

[0277] In this manner, the zone dimension may be indicated via a zone identifier (or Zone_ID). A UE 1702 is shown as being located inside zone 1700.

[0259]

[0278] In the current design, the SL zones are defined with reference to global geographic coordinates (latitude and longitude). In particular, the (0,0) coordinate is a global geographic coordinate (e.g., based on GNSS, etc.), which is typically predefined in the relevant standard. In other designs, the reference geographic coordinate may be defined more flexibly (e.g., a local reference geographic coordinate may be defined, or even a global reference geographic coordinate may be defined that may differ from the predefined reference global geographic coordinate used in the legacy system).

[0260]

[0279] A set of resource elements (REs) used for transmission of a PRS is called a "PRS resource." A set of resource elements may span multiple PRBs in the frequency domain and "N" consecutive symbol(s) (e.g., one or more) within a slot in the time domain. Within a given OFDM symbol in the time domain, a PRS resource occupies consecutive PRBs in the frequency domain.

[0261]

[0280] The transmission of PRS resources within a given PRB has a certain comb size (also called "comb density"). Comb size "N" represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the PRS resource configuration. In particular, for comb size "N", the PRS is transmitted on every Nth subcarrier of the PRB symbol. For example, for comb 4, for each symbol of the PRS resource configuration, the RE corresponding to every fourth subcarrier (such as subcarriers 0, 4, 8) is 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.

[0262]

[0281] Currently, DL-PRS resources may span 2, 4, 6, or 12 consecutive symbols in a slot with a staggered pattern across the frequency domain. DL-PRS resources may be configured in any higher layer configured downlink or flexible (FL) symbols of a slot. There may be a constant energy per resource element (EPRE) for all REs of a given DL-PRS resource. Below are the symbol-to-symbol frequency offsets for comb sizes 2, 4, 6, and 12 across 2, 4, 6, and 12 symbols. 2symbolscom2:{0,1}; 4symbolscom2:{0,1,0,1}; 6symbolscom2:{0,1,0,1,0,1}; 12symbolscom2:{0,1,0,1,0,1,0,1,0,1,0,1,0,1}; (for the example in Figure 4), 4symbolscom4:{0,2,1,3}; 12symbolscom4:{0,2,1,3,0,2,1,3,0,2,1,3}; 6symbolscom6:{0,3,1,4,2,5}; 12symbolscom6{0,3,1,4,2,5,0,3,1,4,2,5}; and 12symbolscom12:{0,6,3,9,1,7,4,10,2,8,5,11}.

[0263]

[0282] A "PRS resource set" is a collection of PRS resources used for transmission of a PRS signal, where each PRS resource has a PRS resource ID. In addition, 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). In addition, the PRS resources in a PRS resource set have the same periodicity across slots, a common muting pattern configuration, and the same repetition factor (e.g., "PRS-ResourceRepetitionFactor"). The periodicity is the time from the first repetition of the first PRS resource of the first PRS instance to the same first repetition of the same first PRS resource of the next PRS instance. The periodicity may have a length selected from 2^μ*{4,5,8,10,16,20,32,40,64,80,160,320,640,1280,2560,5120,10240} slots, where μ=0, 1, 2, 3. The repetition factor may have a length selected from {1,2,4,6,8,16,32} slots.

[0264]

[0283] A PRS resource ID in a PRS resource set is associated with a single beam (or beam ID) transmitted from a single TRP (where a TRP may transmit one or more beams). That is, each PRS resource in a PRS resource set may be transmitted on a different beam, and thus a "PRS resource" or simply a "resource" may also be referred to as a "beam." Note that this does not have any implication as to whether the TRP and beam on which the PRS is transmitted are known to the UE.

[0265]

[0284] A "PRS instance" or "PRS occasion" is one instance of a periodically repeating time window (e.g., a group of one or more contiguous slots) during which a PRS is expected to be transmitted. A PRS occasion may also be referred to as a "PRS positioning occasion", "PRS positioning instance", "positioning occasion", "positioning instance", "positioning repetition", or simply an "occasion", "instance", or "repetition".

[0266]

[0285] A "positioning frequency layer" (also simply called "frequency layer") is a collection of one or more PRS resources across one or more TRPs with the same values ​​for certain parameters. In particular, a collection of PRS resource sets has the same subcarrier spacing and cyclic prefix (CP) type (meaning that all numerologies supported for the physical downlink shared channel (PDSCH) are also supported for the PRS), the same Point A, the same value of the 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"), which is an identifier / code that specifies a pair of physical radio channels used for transmission and reception. The downlink PRS bandwidth may have a granularity of 4 PRB, with a minimum of 24 PRB and a maximum of 272 PRB. Currently, up to four frequency layers are defined, and up to two PRS resource sets per TRP per frequency layer can be configured.

[0267]

[0286] The concept of frequency layer is somewhat like that of component carrier and bandwidth portion (BWP), but differs in that component carrier and BWP are used by one base station (or macrocell base station and small cell base station) to transmit data channels, whereas frequency layer is used by several (usually more than two) base stations to transmit PRS. A UE may indicate the number of frequency layers that it can support when it sends its positioning capabilities to the network, such as during an LTE positioning protocol (LPP) session. For example, a UE may indicate that it can support one positioning frequency layer or four positioning frequency layers.

[0268]

[0287] It should be noted 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" may also refer to any type of reference signal that can be used for positioning, such as, but not limited to, PRS as defined in LTE and NR, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, etc. Furthermore, the terms "positioning reference signal" and "PRS" may also refer to downlink or uplink positioning reference signals, unless otherwise indicated by the context. If necessary to further distinguish between types of PRS, downlink positioning reference signals may be referred to as "DL-PRS" and uplink positioning reference signals (e.g., SRS for positioning, PTRS) may be referred to as "UL-PRS". In addition, for signals that may be transmitted in both uplink and downlink (e.g., DMRS, PTRS), "UL" or "DL" may be prepended to the signal to distinguish the direction. For example, "UL-DMRS" can be distinguished from "DL-DMRS."

[0269]

[0288] In some designs, Uu PRS transmissions (e.g., DL PRS, UL SRS-P, etc.) are scheduled by the network using a network-assigned PRS sequence ID for PRS sequence generation. For example, DL PRS sequences are generated using a network-assigned PRS sequence ID, slot number, and symbol. A receiving UE is expected to receive and decode / descramble PRS with a configured set of PRS sequence IDs. In other words, a receiving UE is not expected to perform a blind search for DL ​​PRS. In some designs, there may be as many as 4096 distinct PRS sequence IDs, such that a blind search would consume power and consume significant resources at a receiving UE. For this reason, various legacy designs rely on centralized scheduling and configuration of PRS.

[0270]

[0289] However, in a sidelink environment, centralized scheduling and configuration of PRS may suffer from high overhead due to dynamic topology. For example, target UE and / or anchor UE(s) may be moving quickly, resulting in frequent SL PRS configuration changes. For a target UE, the SL PRS configuration should be updated when the SL anchor enters / exits its vicinity. Figure 18 illustrates a sidelink zone topology 1800 according to one aspect of the present disclosure. As shown in Figure 18, the SL anchor UE may move in and / or out of the respective sidelink zone where the target UE is located. Each change to the sidelink zone topology 1800 due to a changing SL anchor UE may trigger a SL PRS reconfiguration, which leads to high reconfiguration overhead.

[0271]

[0290] For SL anchor UEs, the LMF may need to update its PRS configuration to avoid PRS collisions, and thus the PRS sequence ID and scheduling are used by the SL anchor UE, causing local contention. Figure 19 illustrates an SL anchor UE reconfiguration scheme 1900 according to one aspect of the present disclosure. With reference to Figure 19, assume that UE1, 2, and 3 are SL anchor UEs, whereby UE1 is moving while UE2 and 3 are stationary. At time t1, UE1 is associated with a first SL PRS range 1902, and UE2 and 3 are associated with SL PRS ranges 1904 and 1906, respectively. At time t2, UE1 changes location and is associated with SL PRS range 1908, which partially overlaps with SL PRS range 1904. Thus, at time t2, the LMF may need to update the SL PRS configurations of UE1 and / or UE2 to ensure that UE1 and UE2 are not using the same PRS sequence ID, which leads to high reconfiguration overhead.

[0272]

[0291] 20 illustrates an SL zone configuration 2000 according to one aspect of the disclosure. Target and anchor UEs may move throughout various SL zones of the SL zone configuration 2000. As mentioned above, this may cause high SL PRS reconfiguration overhead if a centralized approach is used for allocation of SL PRS configurations, including PRS sequence IDs.

[0273]

[0292] Aspects of the present disclosure are directed to associating a set of PRS sequences with a particular SL zone. In some designs, such aspects may enable a target UE to perform a blind search (or blind decoding and / or blind descrambling) within a reduced PRS search space such that a centralized SL PRS configuration scheme may be avoided. Such aspects may provide various technical advantages, such as facilitating an SL-aided position estimation scheme with less SL PRS reconfiguration overhead than various legacy systems.

[0274]

[0293] 21 illustrates an example process 2100 for wireless communication according to an aspect of the disclosure. In one aspect, the process 2100 may be performed by a UE, such as the UE 302. In particular, the UE performing the process 2100 of FIG. 21 corresponds to a UE that transmits a SL PRS in connection with an SL-assisted position estimation procedure.

[0275]

[0294] Referring to FIG. 21, at 2110, the UE 302 (e.g., processor(s) 332, PRS sequence component 342, etc.) determines a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones.

[0276]

[0295] Referring to FIG. 21, at 2120, the UE 302 (e.g., processor(s) 332, PRS sequence component 342, etc.) identifies one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone.

[0277]

[0296] Referring to FIG. 21, at 2130, the UE 302 (eg, transmitter 314 or 324) transmits the sidelink PRS according to the identified PRS sequence.

[0278]

[0297] 22 illustrates an example process 2200 for wireless communication according to an aspect of the disclosure. In one aspect, the process 2200 may be performed by a UE, such as UE 302. In particular, the UE performing the process 2200 of FIG. 22 corresponds to a UE that monitors (e.g., decodes and measures) SL PRSs associated with an SL-assisted location estimation procedure.

[0279]

[0298] Referring to FIG. 22, at 2210, the UE 302 (e.g., processor(s) 332, PRS sequence component 342, etc.) determines a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones.

[0280]

[0299] Referring to FIG. 22, at 2220, the UE 302 (e.g., processor(s) 332, PRS sequence component 342, etc.) identifies one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone.

[0281]

[0300] 22, at 2220, the UE 302 (e.g., receiver 312 or 322, processor(s) 332, PRS sequence component 342, etc.) performs a blind search (e.g., blind decoding and / or blind descrambling) for sidelink PRSs based on the one or more identified PRS sequences. In particular, the blind search may be performed for fewer than all possible PRS sequences to reduce power consumption and / or processing load at the UE.

[0282]

[0301] 21-22, in some designs, the sidelink PRS(s) may be transmitted on a common sidelink frequency layer (e.g., to reduce the need to reconfigure the frequency layer for the SL PRS over time).

[0283]

[0302] 21-22, in some designs, multiple reserved PRS resource pools may be associated with a sidelink-assisted position estimation procedure. In this case, one of the one or more reserved PRS resource pools may be used for sidelink PRS transmission at 2130 of FIG. 21, and the UE of FIG. 22 may perform a blind search for each of the respective reserved PRS resource pools at 2230. The particular resource pool used for SL PRS transmission by the UE at 2130 of FIG. 21 may be determined in various manners (e.g., network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with the sidelink zone in which the UE is located).

[0284]

[0303] FIG. 23 illustrates a PRS resource pool configuration 2300 according to one aspect of the disclosure. In FIG. 23, the illustrated frequency ranges may correspond to common sidelink frequency layers as described above. In some designs, the PRS resource pools 2302, 2304, 2306, and 2308 for a particular SL-assisted position estimation session may be staggered at intervals with time gaps disposed therebetween. In some designs, the PRS resource pools 2302, 2304, 2306, and 2308 may be reserved by a position estimation entity. In some designs, the PRS resource pools 2302, 2304, 2306, and 2308 may be coarsely synchronized based on a previous SL-assisted position estimation session or may assume that all UEs participating in the SL-assisted position estimation session are in coverage. In some designs, allocation of UEs to PRS resource pools may be scheduled via broadcast (e.g., in each PRS pool, a subset of UEs will transmit on the same symbols, but their SL-PRSs are scrambled with different sequences or code division multiplexing (CDM)).

[0285]

[0304] With reference to FIG. 21 , in some designs, the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof. For example, the SL PRS sequence may be based on one or more of an SL zone ID, an SL UE ID, a slot number in the (SFN / DFN), a symbol number in the slot, etc. In an example in which the SL PRS sequence is based on the SL zone ID, the UE may select a PRS sequence ID (e.g., from a subset of PRS sequence IDs available for that particular SL zone ID) and then generate the PRS sequence. In some designs, each SL zone ID may be associated with a pool of PRS sequence IDs. In some designs, a portion of the SL zone ID may be used directly in the sequence generation (e.g., using the X least significant bits (LSBs) of x1 and y2 for finer spatial division or using the X most significant bits (MSBs) of x1 and y2 for coarser spatial division). In some designs, for some SL zones, there may be only one available PRS sequence ID. In some designs, to avoid PRS sequence collisions, the identified PRS sequence may be selected based in part on a SL UE ID, such as a SL UE ID used for PSSCH scheduling or a sidelink synchronization signal (SLSS) ID.

[0286]

[0305] 21 , in some designs, a sidelink zone identifier in which the UE itself is located (e.g., an initial coarse location estimate) may be determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate (e.g., E-CID) provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs (e.g., SL discovery messages such as PSBCH or SL SIBs, e.g., SL MIB), or one or more measurements by one or more sensors of the UE (e.g., GNSS), or a combination thereof.

[0287]

[0306] With reference to FIG. 21 , in some designs, identifying a PRS sequence may include monitoring one or more sidelink PRSs associated with one or more PRS sequences from one or more other UEs and, based on the monitoring, selecting a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence. For example, the UE may monitor its neighboring selections to avoid PRS sequence collisions. The target UE monitors PRS transmissions and identifies PRS sequences used by the neighboring UEs. The target UE may keep track of available sequences used in each zone (e.g., in SL zone 1, from PRS sequence pool 1, S1-S2 are utilized and S3 is available; in SL zone 2, from PRS sequence pool 2, S4 is utilized and S5-S6 are available, etc.). When the UE enters a new SL zone, the UE may randomly select an available sequence in the SL zone as its new PRS sequence for SL-PRS transmission. In a further design, the UE may detect a PRS sequence collision associated with a transmitted sidelink PRS and may then select a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision. For example, if two UEs enter the same SL zone and select the same sequence, after one PRS session, each UE may identify the collision and reselect their respective PRS sequence in the next PRS session.

[0288]

[0307] With reference to FIG. 21 , in some designs, the identified PRS sequence is assigned to the UE by an external entity (e.g., a local SL zone manager, etc.). For example, a master SL node (e.g., a fixed node such as customer premises equipment (CPE)) manages the SL-PRS sequence pool in the SL zone. When the position estimation entity sends a location estimate to the target UE, the position estimation entity may also send assistance data regarding the master node in the SL zone. The target UE then sends a request for a new PRS sequence from the master node.

[0289]

[0308] 22, similar to FIG. 21, in some designs, a sidelink zone identifier in which the UE itself is located (e.g., an initial coarse location estimate) may be determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate (e.g., E-CID) provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs (e.g., SL discovery messages such as PSBCH or SL SIBs, e.g., SL MIB), or one or more measurements by one or more sensors of the UE (e.g., GNSS), or a combination thereof.

[0290]

[0309] With reference to FIG. 22 , in some designs, the set of sidelink zones includes the sidelink zone in which the UE is located and neighboring nodes of the sidelink zone in which the UE is located. In some designs, the blind search may be limited to PRS sequences associated with this particular set of sidelink zones (e.g., the blind search is performed only on one or more identified PRS sequences). For example, given its own SL zone and / or neighboring SL zones, the UE may infer a set S of potential PRS sequences that may potentially be used by other UEs, may receive SL PRS during scheduled PRS occasions (e.g., for a reserved PRS resource pool, etc.), may perform a blind search (e.g., blind decoding and / or blind descrambling) on ​​the SL PRS using the set S, and may then report any available SL PRS measurements to a position estimation entity. Thus, the UE may send a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via blind search.

[0291]

[0310] 22, in other designs, decoding need not be limited to a blind search of PRS sequences associated with the sidelink zone in which the UE is located and neighboring nodes of the sidelink zone in which the UE is located. For example, a blind search may be performed for one or more identified PRS sequences as described above, and an additional (e.g., non-blind) search may be performed for one or more network-configured PRS sequences. For example, some UEs may not support location-based (or SL zone-based) PRS sequence selection and may instead be assigned a PRS sequence by a network component. In this case, the assigned PRS sequence may be signaled to other UEs in the vicinity so that this network-configured PRS sequence is searched in addition to the SL zone-related PRS sequence. For example, given its own SL zone and / or neighboring SL zones, a UE may infer a set S of potential PRS sequences that may potentially be used by other UEs, may determine a set of N network-configured PRS sequences, may receive SL PRS during scheduled PRS occasions (e.g., for a reserved PRS resource pool, etc.), may perform blind searching or blind descrambling for the SL PRS using normal (or non-blind) searching or descrambling on set S as well as set N, and may then report any available SL PRS measurements to a position estimation entity. Thus, a UE may send a measurement report based on one or more positioning measurements of one or more sidelink PRS performed via searching.

[0292]

[0311] 24 illustrates an SL zone configuration 2400 according to an aspect of the disclosure. In FIG. 24, UEs 1-10 are located in a first SL zone, and UEs 11-15 are located in a second SL zone. As mentioned above, in some designs, some or all of UEs 1-15 may participate in the SL-assisted location estimation procedure, whereby each respective UE transmits an SL PRS and / or performs a blind search for an SL PRS based in part on the SL zone-related PRS sequence, which may help limit SL PRS reconfiguration overhead while also limiting the scope of the blind search.

[0293]

[0312] In the current Uu design, each measurement report from a UE associated with a location estimation session includes a positioning measurement of the PRS tagged with a TRP ID to identify the transmitter from which the associated PRS is transmitted. In a further aspect of the disclosure, the UE may instead tag the positioning measurement with a PRS sequence (e.g., a corresponding descrambling PRS sequence ID) associated with a particular SL PRS. In this case, the descrambling PRS sequence ID is used by the positioning entity to identify the transmitting UE (e.g., based on an association between the descrambling PRS sequence ID and a UE ID, which is known to the location estimation entity but may not be known to the reporting UE). For example, UEs transmitting SL PRSs may report their respective PRS sequence IDs to the location estimation entity to facilitate correlation of PRS sequences with UE IDs (e.g., to help the location estimation entity identify the transmitting UE in measurement reports of other UEs). Such an aspect may provide various technical advantages, such as streamlining the SL PRS measurement reporting process, such that a UE measuring the SL PRS does not need to identify the UE from which the SL PRS is measured and reported (e.g., such identification may instead occur at the position estimation entity).

[0294]

[0313] 25 illustrates an example process 2500 for wireless communication according to an aspect of the disclosure. In one aspect, the process 2500 may be performed by a UE, such as the UE 302.

[0295]

[0314] Referring to FIG. 25, at 2510, the UE 302 (e.g., receiver 312 or 322, PRS sequence component 342, processor(s) 332, etc.) performs one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRSs being associated with a respective PRS sequence (e.g., based on a limited blind search procedure or a target blind search procedure as described above, etc.).

[0296]

[0315] Referring to FIG. 25, at 2520, the UE 302 (e.g., transmitter 314 or 324) transmits a measurement report to a position estimation entity including one or more positioning measurements along with a first indication of a respective PRS sequence for each respective positioning measurement (e.g., in lieu of an explicit identification of the UE(s) transmitting the SL PRS(s)).

[0297]

[0316] With reference to FIG. 25 , in some designs, one or more sidelink PRSs are associated with a sidelink-assisted location estimation procedure. In some designs, as part of the sidelink-assisted location estimation procedure, the UE may also transmit a sidelink PRS (e.g., for RTT measurement, etc.). In this case, the UE may further transmit a second indication of a PRS sequence associated with the transmitted sidelink PRS to the location estimation entity. In this way, another UE can report measurement(s) of the UE's sidelink PRS to the location estimation entity, which can then correlate those measurement(s) to the UE using the second indication.

[0298]

[0317] 25 , in some designs, the sidelink-assisted position estimation procedure is associated with multiple reserved PRS resource pools, and each of the one or more sidelink PRSs is received on one of the multiple reserved PRS resource pools. In some designs, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRSs, one or more receive times of at least one of the sidelink PRSs, or a combination thereof.

[0299]

[0318] 26 illustrates an example process 2600 for wireless communication according to an aspect of the disclosure. In one aspect, the process 2600 may be performed by a location estimation entity such as a UE (e.g., for UE-based location estimation) or a network component (e.g., a gNB such as the BS 304 for a RAN integrated LMF, or a core network integrated LMF, or a location server such as the network entity 306).

[0300]

[0319] Referring to FIG. 26, at 2610, a position estimation entity (e.g., receiver 312 or 322 or 352 or 362, network transceiver(s) 380 or 390, etc.) receives a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink-assisted position estimation procedure, where the measurement report includes a first indication of a PRS sequence of the respective positioning measurements.

[0301]

[0320] 26, a position estimation entity (e.g., receiver 312 or 322 or 352 or 362, network transceiver(s) 380 or 390, etc.) may receive 2620 a second indication of PRS sequences to be used by a set of user equipment (UE) for transmission of sidelink PRS. In some designs, at least some of the set of UEs providing the second indication at 2620 may also provide at least some of the measurement reports along with the first indication at 2610. In other designs, some UEs may provide the second indication without the first indication (e.g., some UEs may transmit SL PRS without measuring or reporting SL PRS from other UEs).

[0302]

[0321] Referring to FIG. 26, at 2630, a position estimation entity (e.g., processor(s) 332 or 384 or 394, PRS sequence component 342 or 388 or 398, etc.) correlates the positioning measurements with a set of UEs by matching the first indication to the second indication.

[0303]

[0322] Referring to FIG. 26, at 2640, a position estimation entity (e.g., processor(s) 332 or 384 or 394, PRS sequence component 342 or 388 or 398, etc.) determines a position estimate for the target UE based on the correlated measurements from 2630.

[0304]

[0323] 26 , in some designs, the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof. In some designs, the location estimate is determined via a round-trip time (RTT) location estimation scheme. In some designs, the location estimate may be sent by a location estimation entity to the LCS client (target UE) (e.g., directly or via a lead UE of a sidelink UE group).

[0305]

[0324] 26 , in some designs, the location estimation entity may collect all measurements and assistance data (e.g., scheduled transmission times and PRS sequences selected by nearby UEs) to identify the transmitting UE, and then calculate the RTT time. In some designs, the SL range is limited (e.g., to less than 100 m or 300 ns of propagation time). With reasonable scheduling (e.g., the time gap between two consecutive time slots may be greater than 100 ns, e.g., 0.5 ms), Rx-Tx may be calculated as n * The RTT is approximately equal to the time gap. Using the Rx-Tx and the transmit time slot of the target UE, the location estimation entity can find the transmit time slot of the nearby UE. In combination with the code ID, the location estimation entity can identify the nearby UE. The location estimation entity can then find the RTT based on the Rx-Tx. In some designs, if only one Rx-Tx is available, this RTT may be ignored. An example of this procedure is shown in FIG. 27.

[0306]

[0325] FIG. 27 illustrates a PRS resource pool configuration 2700 according to an aspect of the disclosure. In FIG. 27, the illustrated frequency ranges may correspond to common sidelink frequency layers as described above. In some designs, the PRS resource pools 2702, 2704, 2706, and 2708 for a particular SL-assisted position estimation session may be staggered at intervals with a time gap disposed therebetween. In some designs, the PRS resource pools 2702, 2704, 2706, and 2708 may be reserved by a position estimation entity. In some designs, the PRS resource pools 2702, 2704, 2706, and 2708 may be coarsely synchronized based on a previous SL-assisted position estimation session or may assume that all UEs participating in the SL-assisted position estimation session are in coverage. In some designs, allocation of UEs to PRS resource pools may be scheduled via broadcast (e.g., in each PRS pool, a subset of UEs will transmit on the same symbols, but their SL-PRSs are scrambled with different sequences or code division multiplexing (CDM)).

[0307]

[0326] 27 , in some designs, assume that UE2 transmits SL PRS on PRS resource pool 2702 with PRS sequence 3, target UE transmits SL PRS on PRS resource pool 2704 with PRS sequence 1, UE1 transmits SL PRS on PRS resource pool 2706 with PRS sequence 4, and UE3 transmits SL PRS on PRS resource pool 2708 with PRS sequence 5. In this example, the measurement report from the target UE may include two Rx-Tx measurements (RxTx1 with a first indication of PRS sequence 5 and RxTx2 with a first indication of PRS sequence 3) and a second indication of PRS sequence 1 (i.e., indicating the PRS sequence used by the target UE itself). Then, assuming that UE2 and 3 report their respective PRS sequences to a position estimation entity, the position estimation entity can correlate the various PRS sequences to the respective UEs for position estimation.

[0308]

[0327] In the above detailed description, it is seen that various features are grouped together in the examples. This manner of disclosure should not be understood as an intention that the exemplary clauses have more features than are expressly stated in each clause. Rather, various aspects of the disclosure may include fewer than all features of each disclosed exemplary clause. Thus, the following clauses should be considered as incorporated in the description, and each clause may stand alone as a separate example. Although each dependent clause may refer to a specific combination with one of the other clauses in the clause, the aspect(s) of the dependent clause are not limited to that specific combination. It will be understood that other exemplary clauses may also include combinations of the aspect(s) of the dependent clause with the subject matter of any other dependent clause or independent clause, or combinations of any features with other dependent clauses and independent clauses. Unless a specific combination is not intended (e.g., conflicting aspects such as defining an element as both an insulator and a conductor) is expressly expressed or can be easily inferred, the various aspects disclosed herein expressly include these combinations. It is further contemplated that aspects of a clause may be included in any other independent clause, even if the clause is not directly dependent on the independent clause.

[0309]

[0328] The following numbered clauses describe example implementations.

[0310]

[0329] Clause 1. A method of operating a user equipment (UE), comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identifying one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone; and transmitting a sidelink PRS according to the identified PRS sequence.

[0311]

[0330] Clause 2. The method of clause 1, wherein the sidelink PRS is transmitted on a common sidelink frequency layer.

[0312]

[0331] Clause 3. The method of any of clauses 1 to 2, wherein a plurality of reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, further comprising determining one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0313]

[0332] Clause 4. The method according to clause 3, wherein the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with a sidelink zone in which the UE is located.

[0314]

[0333] Clause 5. The method of any of clauses 1 to 4, wherein the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number at which the sidelink PRS is transmitted, a symbol number at which the sidelink PRS is transmitted, or a combination thereof.

[0315]

[0334] Clause 6. The method of any of clauses 1 to 5, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided by a network component, or an initial location estimate provided by a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0316]

[0335] Clause 7. The method of any of clauses 1 to 6, wherein identifying includes monitoring one or more sidelink PRS sequences associated with one or more PRS sequences from the one or more other UEs, and selecting, based on the monitoring, a respective PRS sequence not being used by the one or more other UEs as the identified PRS sequence.

[0317]

[0336] Clause 8. The method of any of clauses 1 to 7, further comprising detecting a PRS sequence collision associated with a transmitted sidelink PRS and selecting a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0318]

[0337] Clause 9. The method of any of clauses 1 to 8, wherein the identified PRS sequence is assigned to the UE by an external entity.

[0319]

[0338] Clause 10. A method of operating a user equipment (UE), comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identifying one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone; and performing a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0320]

[0339] Clause 11. The method of clause 10, wherein the blind search is performed on a common sidelink frequency layer.

[0321]

[0340] Clause 12. The method of any of clauses 10 to 11, wherein the blind search is performed for a plurality of reserved PRS resource pools associated with the sidelink assisted location estimation procedure.

[0322]

[0341] Clause 13. The method of any of clauses 10 to 12, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided by a network component, or an initial location estimate provided by a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0323]

[0342] Clause 14. The method according to any of clauses 10 to 13, wherein the set of sidelink zones comprises the sidelink zone in which the UE is located and neighbouring nodes of the sidelink zone in which the UE is located.

[0324]

[0343] Clause 15. The method of any of clauses 10 to 14, further comprising transmitting a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via blind search.

[0325]

[0344] Clause 16. The method of any of clauses 10 to 15, wherein the blind search is performed only for the one or more identified PRS sequences.

[0326]

[0345] Clause 17. The method of any of clauses 10 to 16, wherein a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0327]

[0346] Clause 18. A method of operating a user equipment (UE), the method comprising: performing one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRS being associated with a respective PRS sequence; and transmitting a measurement report to a position estimation entity, the measurement report including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0328]

[0347] Clause 19. The method according to clause 18, wherein one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0329]

[0348] Clause 20. The method of clause 19, further comprising transmitting a sidelink PRS as part of a sidelink assisted position estimation procedure, and transmitting a second indication of a PRS sequence associated with the transmitted sidelink PRS to a position estimation entity.

[0330]

[0349] Clause 21. The method of any of clauses 19 to 20, wherein the sidelink assisted position estimation procedure is associated with a plurality of reserved PRS resource pools, and the one or more sidelink PRSs are each received on one of the plurality of reserved PRS resource pools.

[0331]

[0350] Clause 22. The method of any of clauses 18 to 21, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0332]

[0351] Clause 23. A method of operating a position estimation entity, the method comprising: receiving a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink-assisted position estimation procedure, the measurement report including a first indication of PRS sequences for each of the positioning measurements; receiving a second indication of PRS sequences to be used by a set of user equipments (UEs) for transmission of the sidelink PRS; correlating the positioning measurements with the set of UEs by matching the first indication to the second indication; and determining a position estimate for a target UE based on the correlation.

[0333]

[0352] Clause 24. The method of clause 23, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0334]

[0353] Clause 25. The method of any of clauses 23 to 24, wherein the location estimate is determined via a round-trip time (RTT) location estimation scheme.

[0335]

[0354] Clause 26. A user equipment (UE), comprising: a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to: determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identify one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone; and transmit, via the at least one transceiver, a sidelink PRS according to the identified PRS sequence.

[0336]

[0355] Clause 27. The UE of clause 26, wherein the sidelink PRS is transmitted on a common sidelink frequency layer.

[0337]

[0356] Clause 28. The UE of any of clauses 26 to 27, wherein a plurality of reserved PRS resource pools are associated with the sidelink assisted location estimation procedure, and the at least one processor is further configured to determine one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0338]

[0357] Clause 29. The UE of clause 28, wherein the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with a sidelink zone in which the UE is located.

[0339]

[0358] Clause 30. The UE of any of clauses 26 to 29, wherein the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number at which the sidelink PRS is transmitted, a symbol number at which the sidelink PRS is transmitted, or a combination thereof.

[0340]

[0359] Clause 31. The UE according to any of clauses 26 to 30, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided by a network component, or an initial location estimate provided by a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0341]

[0360] Clause 32. The UE of any of clauses 26 to 31, wherein the identifying comprises monitoring one or more sidelink PRS sequences associated with one or more PRS sequences from the one or more other UEs, and selecting, based on the monitoring, a respective PRS sequence not in use by the one or more other UEs as the identified PRS sequence.

[0342]

[0361] Clause 33. The UE of any of clauses 26 to 32, wherein the at least one processor is further configured to detect a PRS sequence collision associated with a transmitted sidelink PRS and to select a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0343]

[0362] Clause 34. The UE of any of clauses 26 to 33, wherein the identified PRS sequence is assigned to the UE by an external entity.

[0344]

[0363] Clause 35. A user equipment (UE), comprising: a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to: determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones; identify one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone; and perform a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0345]

[0364] Clause 36. The UE of clause 35, wherein the blind search is performed on a common sidelink frequency layer.

[0346]

[0365] Clause 37. The UE of any of clauses 35 to 36, wherein the blind search is performed for a plurality of reserved PRS resource pools associated with the sidelink assisted location estimation procedure.

[0347]

[0366] Clause 38. The UE according to any of clauses 35 to 37, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided by a network component, or an initial location estimate provided by a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0348]

[0367] Clause 39. The UE according to any of clauses 35 to 38, wherein the set of sidelink zones comprises a sidelink zone in which the UE is located and neighbouring nodes of the sidelink zone in which the UE is located.

[0349]

[0368] Clause 40. The UE of any of clauses 35 to 39, wherein the at least one processor is further configured to transmit, via the at least one transceiver, a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via blind search.

[0350]

[0369] Clause 41. The UE of any of clauses 35 to 40, wherein the blind search is performed only for the one or more identified PRS sequences.

[0351]

[0370] Clause 42. The UE of any of clauses 35 to 41, wherein a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network configured PRS sequences.

[0352]

[0371] Clause 43. A user equipment (UE), comprising: a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to perform one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRS being associated with a respective PRS sequence, and to transmit, via the at least one transceiver, a measurement report to a position estimation entity, the measurement report including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0353]

[0372] Clause 44. The UE of clause 43, wherein one or more sidelink PRSs are associated with a sidelink assisted location estimation procedure.

[0354]

[0373] Clause 45. The UE of clause 44, wherein the at least one processor is further configured to transmit, via the at least one transceiver, a sidelink PRS as part of a sidelink assisted position estimation procedure, and to transmit, via the at least one transceiver, a second indication of a PRS sequence associated with the transmitted sidelink PRS to the position estimation entity.

[0355]

[0374] Clause 46. The UE of any of clauses 44 to 45, wherein the sidelink assisted location estimation procedure is associated with a plurality of reserved PRS resource pools, and wherein one or more sidelink PRS are each received on one of the plurality of reserved PRS resource pools.

[0356]

[0375] Clause 47. The UE of any one of clauses 43 to 46, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0357]

[0376] Clause 48. A location estimation entity comprising: a memory; at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to: receive, via the at least one transceiver, measurement reports including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink assisted location estimation procedure, the measurement reports including a first indication of PRS sequences for each of the positioning measurements; receive, via the at least one transceiver, a second indication of PRS sequences used by a set of user equipments (UEs) for sidelink PRS transmissions; and correlate the positioning measurements with the set of UEs by matching the first indication to the second indication, to determine a location estimate for a target UE based on the correlating.

[0358]

[0377] Clause 49. The position estimation entity of clause 48, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0359]

[0378] Clause 50. The location estimation entity of any of clauses 48 to 49, wherein the location estimate is determined via a round-trip time (RTT) location estimation scheme.

[0360]

[0379] Clause 51. A user equipment (UE), comprising: means for determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; means for identifying one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone; and means for transmitting a sidelink PRS according to the identified PRS sequence.

[0361]

[0380] Clause 52. The UE of clause 51, wherein the sidelink PRS is transmitted on a common sidelink frequency layer.

[0362]

[0381] Clause 53. The UE of any of clauses 51 to 52, wherein a plurality of reserved PRS resource pools are associated with the sidelink assisted location estimation procedure, further comprising means for determining one of the one or more reserved PRS resource pools for transmission of a sidelink PRS.

[0363]

[0382] Clause 54. The UE of clause 53, wherein the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with a sidelink zone in which the UE is located.

[0364]

[0383] Clause 55. The UE of any of clauses 51 to 54, wherein the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number at which the sidelink PRS is transmitted, a symbol number at which the sidelink PRS is transmitted, or a combination thereof.

[0365]

[0384] Clause 56. The UE according to any of clauses 51 to 55, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided by a network component, or an initial location estimate provided by a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0366]

[0385] Clause 57. The UE of any of clauses 51 to 56, wherein the means for identifying includes means for monitoring one or more sidelink PRS sequences associated with one or more PRS sequences from the one or more other UEs, and means for selecting, based on the monitoring, a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence.

[0367]

[0386] Clause 58. The UE of any of clauses 51 to 57, further comprising means for detecting a PRS sequence collision associated with a transmitted sidelink PRS, and means for selecting a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0368]

[0387] Clause 59. The UE of any of clauses 51 to 58, wherein the identified PRS sequence is assigned to the UE by an external entity.

[0369]

[0388] Clause 60. A user equipment (UE), comprising: means for determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; means for identifying one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone; and means for performing a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0370]

[0389] Clause 61. The UE of clause 60, wherein the blind search is performed on a common sidelink frequency layer.

[0371]

[0390] Clause 62. The UE of any of clauses 60 to 61, wherein the blind search is performed for a plurality of reserved PRS resource pools associated with the sidelink assisted location estimation procedure.

[0372]

[0391] Clause 63. The UE of any of clauses 60 to 62, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0373]

[0392] Clause 64. The UE of any of clauses 60 to 63, wherein the set of sidelink zones includes a sidelink zone in which the UE is located and neighbouring nodes of the sidelink zone in which the UE is located.

[0374]

[0393] Clause 65. The UE of any of clauses 60 to 64, further comprising means for transmitting a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via blind search.

[0375]

[0394] Clause 66. The UE of any of clauses 60 to 65, wherein the blind search is performed only for the one or more identified PRS sequences.

[0376]

[0395] Clause 67. The UE of any of clauses 60 to 66, wherein a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network configured PRS sequences.

[0377]

[0396] Clause 68. A user equipment (UE), comprising: means for performing one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRS being associated with a respective PRS sequence, and means for transmitting a measurement report to a position estimation entity, the measurement report including the one or more positioning measurements together with a first indication of a respective PRS sequence for each respective positioning measurement.

[0378]

[0397] Clause 69. The UE of clause 68, wherein one or more sidelink PRSs are associated with a sidelink assisted location estimation procedure.

[0379]

[0398] Clause 70. The UE of clause 69, further comprising: means for transmitting a sidelink PRS as part of a sidelink assisted position estimation procedure; and means for transmitting to a position estimation entity a second indication of a PRS sequence associated with the transmitted sidelink PRS.

[0380]

[0399] Clause 71. The UE of any of clauses 69 to 70, wherein the sidelink assisted location estimation procedure is associated with a plurality of reserved PRS resource pools, and wherein one or more sidelink PRS are each received on one of the plurality of reserved PRS resource pools.

[0381]

[0400] Clause 72. The UE of any of clauses 68 to 71, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0382]

[0401] Clause 73. A position estimation entity, comprising: means for receiving a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink-assisted position estimation procedure, the measurement report including a first indication of PRS sequences for each of the positioning measurements; means for receiving a second indication of PRS sequences to be used by a set of user equipments (UEs) for transmission of the sidelink PRS; means for correlating the positioning measurements with the set of UEs by matching the first indication to the second indication; and means for determining a position estimate for a target UE based on the correlation.

[0383]

[0402] Clause 74. The position estimation entity of clause 73, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0384]

[0403] Clause 75. The location estimation entity of any of clauses 73 to 74, wherein the location estimate is determined via a round-trip time (RTT) location estimation scheme.

[0385]

[0404] Clause 76. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identify one of a plurality of positioning reference signal (PRS) sequences associated with the identified sidelink zone, and transmit a sidelink PRS according to the identified PRS sequence.

[0386]

[0405] Clause 77. The non-transitory computer-readable medium of clause 76, wherein the sidelink PRS is transmitted on a common sidelink frequency layer.

[0387]

[0406] Clause 78. The non-transitory computer-readable medium of any of clauses 76 to 77, wherein a plurality of reserved PRS resource pools are associated with the sidelink assisted position estimation procedure, and the instructions further cause the UE to determine one of the one or more reserved PRS resource pools for transmission of the sidelink PRS.

[0388]

[0407] Clause 79. The non-transitory computer-readable medium of clause 78, wherein the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on a sidelink zone identifier associated with a sidelink zone in which the UE is located.

[0389]

[0408] Clause 80. The non-transitory computer-readable medium of any of clauses 76-79, wherein the identified PRS sequence is identified based on a sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof.

[0390]

[0409] Clause 81. The non-transitory computer-readable medium of any of clauses 76 to 80, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0391]

[0410] Clause 82. The non-transitory computer-readable medium of any of clauses 76-81, wherein identifying includes monitoring one or more sidelink PRS sequences associated with one or more PRS sequences from the one or more other UEs, and selecting, based on the monitoring, a respective PRS sequence not used by the one or more other UEs as the identified PRS sequence.

[0392]

[0411] Clause 83. The non-transitory computer-readable medium of any of clauses 76 to 82, wherein the one or more instructions further cause the UE to detect a PRS sequence collision associated with the transmitted sidelink PRS and select a different PRS sequence for PRS retransmission in response to the detected PRS sequence collision.

[0393]

[0412] Clause 84. The non-transitory computer-readable medium of any of clauses 76 to 83, wherein the identified PRS sequence is assigned to the UE by an external component.

[0394]

[0413] Clause 85. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to determine a sidelink zone identifier associated with a sidelink zone in which the UE is located, where the sidelink zone corresponds to one of a plurality of sidelink zones, identify one or more positioning reference signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, and perform a blind search for a sidelink PRS based on the one or more identified PRS sequences.

[0395]

[0414] Clause 86. The non-transitory computer-readable medium of clause 85, wherein the blind search is performed on a common sidelink frequency layer.

[0396]

[0415] Clause 87. The non-transitory computer-readable medium of any of clauses 85 to 86, wherein the blind search is performed on a plurality of reserved PRS resource pools associated with the sidelink assisted position estimation procedure.

[0397]

[0416] Clause 88. The non-transitory computer-readable medium of any of clauses 85 to 87, wherein the sidelink zone identifier is determined based on an initial PRS sequence identifier provided from a network component, or an initial location estimate provided from a network component, or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE, or a combination thereof.

[0398]

[0417] Clause 89. The non-transitory computer-readable medium of any of clauses 85 to 88, wherein the set of sidelink zones includes a sidelink zone in which the UE is located and a neighbor node of the sidelink zone in which the UE is located.

[0399]

[0418] Clause 90. The non-transitory computer-readable medium of any of clauses 85 to 89, wherein the instructions further cause the UE to transmit a measurement report based on one or more positioning measurements of one or more sidelink PRSs performed via blind search.

[0400]

[0419] Clause 91. The non-transitory computer-readable medium of any of clauses 85 to 90, wherein the blind search is performed only on the one or more identified PRS sequences.

[0401]

[0420] Clause 92. The non-transitory computer-readable medium of any of clauses 85 to 91, wherein a blind search is performed for one or more identified PRS sequences and an additional search is performed for one or more network-configured PRS sequences.

[0402]

[0421] Clause 93. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a UE, cause the UE to perform one or more positioning measurements based on one or more sidelink positioning reference signals (PRS) from one or more other UEs, each of the one or more sidelink PRSs being associated with a respective PRS sequence, and to transmit a measurement report to a position estimation entity, the measurement report including the one or more positioning measurements along with a first indication of a respective PRS sequence for each respective positioning measurement.

[0403]

[0422] Clause 94. The non-transitory computer-readable medium of clause 93, wherein one or more sidelink PRSs are associated with a sidelink assisted position estimation procedure.

[0404]

[0423] Clause 95. The non-transitory computer-readable medium of clause 94, the one or more instructions further causing the UE to transmit a sidelink PRS as part of a sidelink assisted position estimation procedure and to transmit a second indication of a PRS sequence associated with the transmitted sidelink PRS to the position estimation entity.

[0405]

[0424] Clause 96. The non-transitory computer-readable medium of any of clauses 94-95, wherein the sidelink assisted position estimation procedure is associated with a plurality of reserved PRS resource pools, and one or more sidelink PRSs are each received on one of the plurality of reserved PRS resource pools.

[0406]

[0425] Clause 97. The non-transitory computer-readable medium of any of clauses 93 to 96, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0407]

[0426] Clause 98. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a position estimation entity, cause the position estimation entity to receive a measurement report including positioning measurements based on sidelink positioning reference signals (PRS) of a sidelink-assisted position estimation procedure, the measurement report including a first indication of a PRS sequence for each of the positioning measurements, receive a second indication of a PRS sequence used by a set of user equipment (UE) for sidelink PRS transmissions, and correlate the positioning measurements with a set of UEs by matching the first indication to the second indication, and determine a position estimate for a target UE based on the correlation.

[0408]

[0427] Clause 99. The non-transitory computer-readable medium of clause 98, wherein the one or more positioning measurements include two or more receive-transmit (Rx-Tx) measurements, one or more transmit times of one or more of the sidelink PRS, one or more receive times of at least one of the sidelink PRS, or a combination thereof.

[0409]

[0428] Clause 100. The non-transitory computer-readable medium of any of clauses 98-99, wherein the location estimate is determined via a round-trip time (RTT) location estimation scheme.

[0410]

[0429] Those skilled in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, the data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0411]

[0430] Moreover, those skilled in the art will appreciate that the various exemplary logic blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability of hardware and software, various exemplary 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 on the particular application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in various ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0412]

[0431] The various example logic blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or performed using 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 may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0413]

[0432] The methods, sequences, and / or algorithms described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a random access memory (RAM), a flash memory, a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a register, a 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. Alternatively, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., UE). Alternatively, the processor and the storage medium may reside as discrete components in a user terminal.

[0414]

[0433] In one or more exemplary aspects, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted via a computer-readable medium as one or more instructions or code. 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 medium may be any available medium that can be accessed by a computer. By way of example, and not limitation, such computer-readable media may 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 coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included within the definition of media. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blue-ray disc, where disks typically reproduce data magnetically and discs reproduce data optically using lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0415]

[0434] Although the above disclosure illustrates exemplary aspects of the disclosure, it should be noted that various changes and modifications may be made herein without departing from the scope of the disclosure as defined by the appended claims. The functions, steps, and / or actions of the method claims in accordance with the aspects of the disclosure described herein need not be performed in any particular order. Further, although elements of the disclosure may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated.

Claims

1. 1. A method of operating a user equipment (UE), comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; monitoring one or more sidelink positioning reference signal (PRS) associated with one or more PRS sequences from one or more other UEs; selecting, from among a plurality of PRS sequences associated with the identified sidelink zone, one of the plurality of PRS sequences not used by the one or more other UEs based on the monitoring; transmitting a sidelink PRS according to the selected PRS sequence; and A method comprising:

2. 2. The method of claim 1, wherein the sidelink PRS is transmitted on a common sidelink frequency layer.

3. A plurality of reserved PRS resource pools are associated with a sidelink assisted position estimation procedure; determining one of the one or more reserved PRS resource pools for transmission of the sidelink PRS. The method of claim 1.

4. 4. The method of claim 3, wherein the determined reserved PRS resource pool is network configured, randomly selected by the UE, or selected based on the sidelink zone identifier associated to the sidelink zone in which the UE is located.

5. the selected PRS sequence is identified based on the sidelink zone identifier, a sidelink UE identifier of the UE, a slot number in which the sidelink PRS is transmitted, a symbol number in which the sidelink PRS is transmitted, or a combination thereof; or The sidelink zone identifier is an initial PRS sequence identifier provided by a network element, or an initial location estimate provided by the network element; or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE; or Combinations of these The method of claim 1 , wherein the step is determined based on:

6. detecting a PRS sequence collision associated with the transmitted sidelink PRS; and selecting a different PRS sequence for a PRS retransmission in response to the detected PRS sequence collision; The method of claim 1 further comprising:

7. 1. A method of operating a user equipment (UE), comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identifying a plurality of Positioning Reference Signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, the set of sidelink zones being a subset of the plurality of sidelink zones. performing a blind search for sidelink PRS, the blind search being limited to the plurality of identified PRS sequences. A method comprising:

8. The blind search on a common sidelink frequency layer, or For a number of reserved PRS resource pools associated to a sidelink assisted position estimation procedure, The method of claim 7, wherein

9. The sidelink zone identifier is an initial PRS sequence identifier provided by a network element, or an initial location estimate provided by the network element; or one or more sidelink zone identifiers associated with one or more other UEs, or one or more measurements by one or more sensors of the UE; or Combinations of these or 8. The method of claim 7, wherein the set of sidelink zones comprises the sidelink zone in which the UE is located and neighbour nodes of the sidelink zone in which the UE is located.

10. transmitting a measurement report based on one or more positioning measurements of the one or more sidelink PRSs performed via the blind search. The method of claim 7 further comprising:

11. The method of claim 7 , wherein the blind search is performed on the one or more identified PRS sequences and an additional search is performed on one or more network-configured PRS sequences.

12. A user equipment (UE), Memory, At least one transceiver; at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; monitor one or more sidelink positioning reference signal (PRS) associated with one or more PRS sequences from one or more other UEs; selecting, from among a plurality of PRS sequences associated with the identified sidelink zone, one of the plurality of PRS sequences not used by the one or more other UEs based on the monitoring; and transmitting, via the at least one transceiver, a sidelink PRS in accordance with the selected PRS sequence. U.E.

13. A user equipment (UE), Memory, At least one transceiver; at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor comprising: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identifying a plurality of Positioning Reference Signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, the set of sidelink zones being a subset of the plurality of sidelink zones; performing a blind search for sidelink PRS, the blind search being limited to the plurality of identified PRS sequences. The UE is configured to:

14. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; monitoring one or more sidelink positioning reference signal (PRS) associated with one or more PRS sequences from one or more other UEs; selecting, from among a plurality of PRS sequences associated with the identified sidelink zone, one of the plurality of PRS sequences not used by the one or more other UEs based on the monitoring; A non-transitory computer-readable medium for causing a sidelink PRS to be transmitted in accordance with the selected PRS sequence.

15. A non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to: determining a sidelink zone identifier associated with a sidelink zone in which the UE is located, the sidelink zone corresponding to one of a plurality of sidelink zones; identifying a plurality of Positioning Reference Signal (PRS) sequences associated with a set of sidelink zones within a threshold distance to the sidelink zone, the set of sidelink zones being a subset of the plurality of sidelink zones. performing a blind search for sidelink PRS, the blind search being limited to the plurality of identified PRS sequences. Non-transitory computer-readable medium.

Images