Enables group leader or base station based sidelink transmission power control and radio link management

Abstract

Techniques for wireless communications are disclosed. In one aspect, a user equipment (UE) participating in a sidelink communication group increments a transmit counter for each packet sent by a first UE as part of a group communication in the sidelink communication group; increments a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and sends a transmit counter and a receive counter to a network node based on a configuration received from the network node.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the benefit of U.S. Provisional Application No. 63 / 003,121, filed on March 31, 2020, entitled “ENABLING GROUP LEADER-OR BASE STATION-BASED SIDELINK TRANSMIT POWER CONTROL AND RADIO LINK MANAGEMENT,” and U.S. Non-Provisional Application No. 17 / 217,878, filed on March 30, 2021, entitled “ENABLING GROUP LEADER-OR BASE STATION-BASED SIDELINK TRANSMIT POWER CONTROL AND RADIO LINK MANAGEMENT,” both of which are assigned to the present assignee and are expressly incorporated herein by reference in their entirety. Technical Field

[0003] Aspects of the present disclosure generally relate to wireless communications. Background Art

[0004] Wireless communication systems have evolved over several generations, including first generation analog wireless telephone service (1G), second generation (2G) digital wireless telephone service (including transitional 2.5G networks and 2.75G networks), third generation (3G) high speed data, Internet-enabled wireless services, and fourth generation (4G) services (e.g., Long Term Evolution (LTE) or WiMax). There are many different types of wireless communication systems in use today, including cellular and personal communications service (PCS) systems. Examples of known cellular systems include the cellular analog Advanced Mobile Phone System (AMPS), and digital cellular systems based on code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), Global System for Mobile Communications (GSM), and the like.

[0005] The fifth generation (5G) wireless standard, known as New Radio (NR), calls for higher data transmission speeds, a greater number of connections, and better coverage, among other improvements. According to the Next Generation Mobile Networks Alliance, the 5G standard is designed to provide data rates of tens of megabits per second to each of tens of thousands of users and 1 gigabit per second to dozens of employees on an office floor. To support large sensor deployments, hundreds of thousands of simultaneous connections should be supported. As a result, the spectral efficiency of 5G mobile communications should be significantly improved compared to the current 4G standard. In addition, signaling efficiency should be improved and latency should be significantly reduced compared to the current standard.

[0006] By leveraging 5G’s increased data rates and reduced latency, vehicle-to-everything (V2X) communications are being enabled to support autonomous driving applications, such as wireless communications between vehicles, between vehicles and roadside infrastructure, and between vehicles and pedestrians. Summary of the invention

[0007] A brief summary of the invention related to one or more aspects disclosed herein is given below. Therefore, the following summary of the invention should not be considered as an exhaustive overview related to all conceived aspects, nor should it be considered as identifying important or key elements related to all conceived aspects or outlining the scope associated with any particular aspect. Therefore, the sole purpose of the following summary of the invention is to present certain concepts related to one or more aspects related to the mechanisms disclosed herein in a simplified form before the detailed embodiments given below.

[0008] In one aspect, a method for wireless communication performed by a first UE participating in a sidelink communication group includes: incrementing a send counter for each packet sent by the first UE as part of a group communication in the sidelink communication group; incrementing a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and sending a send counter and a receive counter to a network node based on a configuration received from the network node.

[0009] In one aspect, a method for wireless communication performed by a network node associated with a sidelink communication group includes: receiving a transmit counter from a first UE participating in the sidelink communication group, the transmit counter indicating the number of packets sent by the first UE as part of group communication in the sidelink communication group; receiving a receive counter from a second UE participating in the sidelink communication group, the receive counter indicating the number of packets received by the second UE from the first UE as part of group communication in the sidelink communication group; determining whether there is a mismatch between the transmit counter and the receive counter based on the transmit counter and the receive counter; and sending a command to at least the first UE for reestablishing a sidelink with the second UE based on the mismatch between the transmit counter and the receive counter.

[0010] In one aspect, a first UE participating in a sidelink communication group includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to: increment a transmit counter for each packet sent by the first UE as part of a group communication in the sidelink communication group; increment a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and cause at least one transceiver to send a transmit counter and a receive counter to a network node based on a configuration received from the network node.

[0011] In one aspect, a network node associated with a sidelink communication group includes a memory, a communication interface, and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to: receive a transmit counter from a first UE participating in the sidelink communication group via at least one transceiver, the transmit counter indicating the number of packets sent by the first UE as part of group communication in the sidelink communication group; receive a receive counter from a second UE participating in the sidelink communication group via at least one transceiver, the receive counter indicating the number of packets received by the second UE from the first UE as part of group communication in the sidelink communication group; determine whether there is a mismatch between the transmit counter and the receive counter based on the transmit counter and the receive counter; and cause the at least one transceiver to send a command to at least the first UE for reestablishing a sidelink with the second UE based on the mismatch between the transmit counter and the receive counter.

[0012] In one aspect, a first UE participating in a sidelink communication group includes: a component for incrementing a send counter for each packet sent by the first UE as part of a group communication in the sidelink communication group; a component for incrementing a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and a component for sending a send counter and a receive counter to a network node based on a configuration received from the network node.

[0013] In one aspect, a network node associated with a sidelink communication group includes: a component for receiving a send counter from a first UE participating in the sidelink communication group, the send counter indicating the number of packets sent by the first UE as part of a group communication in the sidelink communication group; a component for receiving a receive counter from a second UE participating in the sidelink communication group, the receive counter indicating the number of packets received by the second UE from the first UE as part of a group communication in the sidelink communication group; a component for determining whether there is a mismatch between the send counter and the receive counter based on the send counter and the receive counter; and a component for sending a command to at least the first UE for re-establishing a side link with the second UE based on the mismatch between the send counter and the receive counter.

[0014] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions includes computer-executable instructions, which include: at least one instruction instructing a first UE participating in a sidelink communication group to increment a send counter for each packet sent by the first UE as part of a group communication in the sidelink communication group; at least one instruction instructing the first UE to increment a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and at least one instruction instructing to send a send counter and a receive counter to a network node based on a configuration received from the network node.

[0015] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions includes computer-executable instructions, which include: at least one instruction instructing a network node to receive a send counter from a first UE participating in a side link communication group, the send counter indicating the number of packets sent by the first UE as part of a group communication in the side link communication group; at least one instruction instructing the network node to receive a receive counter from a second UE participating in the side link communication group, the receive counter indicating the number of packets received by the second UE from the first UE as part of a group communication in the side link communication group; at least one instruction instructing the network node to determine whether there is a mismatch between the send counter and the receive counter based on the send counter and the receive counter; and at least one instruction instructing the network node to send a command to at least the first UE to re-establish a side link with the second UE based on the mismatch between the send counter and the receive counter.

[0016] Other objects and advantages associated with the various aspects disclosed herein will be apparent to those skilled in the art based on the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are presented to aid in describing various aspects of the disclosure and are provided solely for illustration of these aspects and not limitation thereof.

[0018] Figure 1 An example wireless communication system in accordance with aspects of the present disclosure is shown.

[0019] Figure 2A and Figure 2B Example wireless network structures in accordance with aspects of the present disclosure are shown.

[0020] Figure 3 An example of a wireless communication system supporting unicast sidelink establishment according to aspects of the present disclosure is shown.

[0021] Figure 4A , Figure 4B and Figure 4Cis a simplified block diagram of several example 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.

[0022] Figure 5 is a diagram illustrating an example base station in communication with an example UE in accordance with aspects of the present disclosure.

[0023] Figure 6 and Figure 7

[0013] Example methods for wireless communications in accordance with aspects of the present disclosure are shown. DETAILED DESCRIPTION

[0024] Various aspects of the present disclosure are provided in the following description and related drawings, which are directed to various examples provided for illustrative purposes. Alternative aspects may be designed without departing from the scope of the present disclosure. In addition, well-known elements of the present disclosure will not be described in detail or will be omitted to avoid confusing the relevant details of the present disclosure.

[0025] The words "exemplary" and / or "example" are used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" and / or "example" is not necessarily to be construed as preferred or advantageous over other aspects. Likewise, the term "aspects of the disclosure" does not require that all aspects of the disclosure include the discussed feature, advantage, or mode of operation.

[0026] Those skilled in the art will appreciate that any of a variety of different techniques and technologies may be used to represent the information and signals described below. For example, depending in part on the specific application, in part on the desired design, in part on the corresponding technology, etc., data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the following specification may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0027] In addition, many aspects are described in terms of sequences of actions to be performed by, for example, elements of a computing device. It should be understood that the various actions described herein may be performed by specific circuits (e.g., application specific integrated circuits (ASICs)), by program instructions executed by one or more processors, or by a combination of the two. In addition, the (one or more) sequences of actions described herein may be considered to be fully embodied in any form of non-transitory computer-readable storage medium, in which a corresponding set of computer instructions is stored, which, when executed, will cause or instruct the associated processor of the device to perform the functions described herein. Therefore, various aspects of the present disclosure may be embodied in a variety of different forms, all of which are considered to be within the scope of the claimed subject matter. In addition, for each aspect described herein, the corresponding form of any such aspect may be described as, for example, "logic configured to perform the action."

[0028] As used herein, unless otherwise noted, the terms "user equipment" (UE), "vehicle UE" (V-UE), "pedestrian UE" (P-UE), and "base station" are not intended to be specific or otherwise limited to any specific radio access technology (RAT). In general, a UE can be any wireless communication device used by a user to communicate over a wireless communication network (e.g., a vehicle onboard computer, a vehicle navigation device, a mobile phone, a router, a tablet, a laptop, an asset location device, a wearable device (e.g., a smart watch, glasses, 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.). A UE can be mobile or can be fixed (e.g., at certain times) and can communicate with a radio access network (RAN). As used herein, the term "UE" can be interchangeably referred to 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.

[0029] A V-UE is a type of UE and may be any in-vehicle wireless communication device, such as a navigation system, an alarm system, a head-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 mobile phone, a tablet, etc.) carried by a driver of a vehicle or a passenger in the vehicle. Depending on the context, the term "V-UE" may refer to an in-vehicle wireless communication device or the vehicle itself. A P-UE is a type of UE and may be a portable wireless communication device carried by a pedestrian (i.e., a user who is not driving or riding in a vehicle). Typically, a UE may communicate with a core network via a RAN, and through the core network, the UE may be connected to an external network such as the Internet and to other UEs. Of course, the UE may also use other mechanisms to connect to the core network and / or the Internet, such as through 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.), and the like.

[0030] A base station may operate according to one of several RATs for communicating with a UE, depending on the network in which it is deployed, and may be alternatively referred to as an access point (AP), a network node, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), a new radio (NR) NodeB (also referred to as a gNB or gNodeB), etc. A base station may be primarily used to support wireless access for a UE, including supporting data, voice, and / or signaling connections for the supported UE. In some systems, a base station may only provide edge node signaling functions, while in other systems, a base station may provide additional control and / or network management functions. The communication link through which a UE may send a signal to a base station is referred to as an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). The communication link through which a base station may send a signal to a UE is referred to as a downlink (DL) or forward link channel (e.g., a paging channel, a control channel, a broadcast channel, a forward traffic channel, etc.). As used herein, the term traffic channel (TCH) may refer to a UL / reverse or DL / forward traffic channel.

[0031] The term "base station" may refer to a single physical transmit-receive point (TRP) or to multiple physical TRPs that may or may not be co-located. For example, where 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. Where the term "base station" refers to multiple co-located physical TRPs, the physical TRP may be an antenna array of the base station (e.g., as in a multiple-input multiple-output (MIMO) system, or where the base station employs beamforming). Where the term "base station" refers to multiple non-co-located physical TRPs, the physical TRP may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transmission medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, the non-co-located physical TRP may be a serving base station that receives measurement reports from a UE and an adjacent base station whose reference radio frequency (RF) signal the UE is measuring. Because, as used herein, a TRP is a point at which a base station transmits and receives wireless signals, references to transmissions from a base station or receptions at a base station will be understood to refer to a specific TRP of a base station.

[0032] In some embodiments supporting positioning of a UE, the base station may not support wireless access of the UE (e.g., may not support data, voice, and / or signaling connections for the UE), but may send a reference RF signal to the UE for measurement by the UE, and / or may receive and measure a signal sent by the UE. Such a base station may be referred to as a positioning beacon (e.g., when sending an RF signal to the UE) and / or as a position measurement unit (e.g., when receiving and measuring an RF signal from the UE).

[0033] "RF signals" include electromagnetic waves of a given frequency that transmit information through the 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, due to the propagation characteristics of RF signals through multipath channels, a receiver may receive multiple "RF signals" corresponding to each transmitted RF signal. 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" where it is clear from the context that the term "signal" refers to a wireless signal or an RF signal.

[0034] Figure 1An example wireless communication system 100 is shown in accordance with various aspects of the present disclosure. The wireless communication system 100 (which may also be referred to as a wireless wide area network (WWAN)) may include various base stations 102 (labeled as "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 one aspect, the macrocell base stations 102 may include eNBs and / or ng-eNBs in which the wireless communication system 100 corresponds to an LTE network, or gNBs in which the wireless communication system 100 corresponds to an NR network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, etc.

[0035] The base stations 102 may collectively form a RAN and interface with a core network 174 (e.g., an evolved packet core (EPC) or a 5G core (5GC)) via a backhaul link 122, and interface to one or more location servers 172 (e.g., a location management function (LMF) or a secure user plane location (SUPL) location platform (SLP)) via 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. The base stations 102 may perform, among other functions, functions related to one or more of: transmitting user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and device tracking, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations 102 may communicate with each other directly or indirectly (eg, via EPC / 5GC) via a backhaul link 134, which may be wired or wireless.

[0036] Base stations 102 may communicate wirelessly with UEs 104. Each of base stations 102 may provide communication coverage for a corresponding geographic coverage area 110. In one aspect, base stations 102 in each geographic coverage area 110 may support one or more cells. A "cell" is a logical communication entity used to communicate with a base station (e.g., via a certain frequency resource referred to as a carrier frequency, component carrier, carrier, frequency 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.) used to distinguish cells operating via 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 other) that may provide access to different types of UEs. Because a cell is supported by a specific base station, the term "cell" may refer to one or both of the logical communication entity and the base station supporting it, depending on the context. In some cases, the term "cell" may also refer to a geographic coverage area of ​​a base station (eg, a sector), as long as a carrier frequency can be detected and used for communications within some portion of the geographic coverage area 110.

[0037] Although the geographic coverage areas 110 of neighboring macrocell base stations 102 may partially overlap (e.g., in a handoff region), some geographic coverage areas 110 may substantially overlap with a larger geographic coverage area 110. For example, a small cell base station 102' (labeled "SC" for "small cell") may have a geographic coverage area 110' that substantially overlaps with the geographic coverage areas 110 of one or more macrocell base stations 102. A network that includes both small cell base stations and macrocell base stations may be referred to as a heterogeneous network. A heterogeneous network may also include a home eNB (HeNB) that may provide services to a restricted group called a closed subscriber group (CSG).

[0038] The communication link 120 between the base station 102 and the UE 104 may include an uplink (also referred to as a reverse link) transmission from the UE 104 to the base station 102 and / or a downlink (DL) (also referred to as a forward link) transmission from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may be over 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).

[0039] The wireless communication system 100 may also include a wireless local area network (WLAN) access point (AP) 150 that communicates with a WLAN station (STA) 152 via a communication link 154 in an unlicensed spectrum (e.g., 5 GHz). When communicating in the unlicensed spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) or listen before talk (LBT) process to determine whether the channel is available before communicating.

[0040] The small cell base station 102' can operate in licensed and / or unlicensed spectrum. When operating in the unlicensed spectrum, the small cell base station 102' can adopt LTE or NR technology and use the same 5GHz unlicensed spectrum used by the WLAN AP 150. The small cell 102' adopting LTE / 5G in the unlicensed spectrum can improve the coverage of the access network and / or increase the capacity of the access network. NR in the unlicensed spectrum can be referred to as NR-U. LTE in the unlicensed spectrum can be referred to as LTE-U, Licensed Assisted Access (LAA) or MulteFire.

[0041] The wireless communication system 100 may also include a mmW base station 180, which may operate at millimeter wave (mmW) frequencies and / or near mmW frequencies to communicate with UE 182. Extremely high frequency (EHF) is part of RF in the electromagnetic spectrum. EHF ranges from 30 GHz to 300 GHz, with wavelengths between 1 mm and 10 mm. Radio waves in this band may be referred to as millimeter waves. Near mmW may extend down to 3 GHz frequencies with a wavelength of 100 mm. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also known as centimeter waves. Communications using mmW / near mmW radio frequency bands have higher path losses and relatively short distances. The mmW base station 180 and UE 182 may utilize beamforming (transmitting and / or receiving) on ​​the mmW communication link 184 to compensate for extremely high path losses and short distances. In addition, it should be understood that in an alternative configuration, one or more base stations 102 may also use mmW or near mmW and beamforming to transmit. Therefore, it should be understood that the foregoing diagrams are merely examples, and should not be construed as limiting the various aspects disclosed herein.

[0042] Transmit beamforming is a technique for focusing an RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omnidirectionally). With transmit beamforming, the network node determines the location of a given target device (e.g., UE) (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster (in terms of data rate) and stronger RF signal to (one or more) receiving devices. In order to change the directionality of the RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters that are broadcasting the RF signal. For example, the network node can use an array of antennas (referred to as a "phased array" or "antenna array") that produces RF wave beams that can be "steered" to point to different directions without actually moving the antenna. Specifically, the RF current from the transmitter is fed to each antenna in the correct phase relationship, so that the radio waves from the separate antennas are added together in the desired direction to increase the radiation, while canceling in the undesired direction to suppress the radiation.

[0043] The transmit beams can be quasi-co-located, which means that they appear to the receiver (e.g., UE) to have the same parameters, regardless of whether the transmit antennas of the network nodes themselves are physically co-located. In NR, there are four types of quasi-co-location (QCL) relationships. Specifically, a given type of QCL relationship means that certain parameters about the second reference RF signal on the second beam can be derived from information about the source reference RF signal on the source beam. Therefore, 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 sent 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 sent 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 the second reference RF signal sent on the same channel. If the source reference RF signal is QCL type D, the receiver can use the source reference RF signal to estimate the spatial reception parameters of the second reference RF signal sent on the same channel.

[0044] In receive beamforming, the receiver uses receive beams to amplify RF signals detected on a given channel. For example, the receiver may increase the gain setting and / or adjust the phase setting of the antenna array in a particular direction to amplify the RF signals received from that direction (e.g., increase its gain level). Therefore, when it is said that the receiver beamforms in a certain direction, it means that the beam gain in that direction is high relative to the beam gain along other directions, or that the beam gain in that direction is the highest compared to the beam gain in that direction of all other receive beams available to the receiver. This results in the RF signal received from that direction having 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.).

[0045] The transmit and receive beams may be spatially correlated. The spatial relationship means that parameters of a second beam (e.g., a transmit or receive beam) for a second reference signal may be derived from information about a first beam (e.g., a receive beam or a transmit beam) for a first reference signal. For example, a UE may use a particular receive beam to receive a reference downlink reference signal (e.g., a synchronization signal block (SSB)) from a base station. The UE may then form a transmit beam for sending an uplink reference signal (e.g., a sounding reference signal (SRS)) to the base station based on the parameters of the receive beam.

[0046] 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 is forming a downlink beam to send a reference signal to the UE, the downlink beam is a transmit beam. However, if the UE is forming a downlink beam, it is a receive beam used to receive the 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 is forming an uplink beam, it is an uplink receive beam, and if the UE is forming an uplink beam, it is an uplink transmit beam.

[0047] In 5G, the spectrum in which wireless nodes (e.g., base stations 102 / 180, UEs 104 / 182) operate is divided into multiple frequency ranges: FR1 (from 450MHz to 6000MHz), FR2 (from 24250MHz to 52600MHz), FR3 (above 52600MHz), and FR4 (between FR1 and FR2). The mmW band generally includes the FR2, FR3, and FR4 frequency ranges. Therefore, the terms "mmW" and "FR2" or "FR3" or "FR4" are generally used interchangeably.

[0048] In a multi-carrier system such as 5G, one of the carrier frequencies is referred to as the "primary carrier" or "anchor carrier" or "primary serving cell" or "PCell", while the remaining carrier frequencies are referred to as "secondary carriers" or "secondary serving cells" or "Scells". In carrier aggregation, the anchor carrier is a carrier operating on the primary frequency (e.g., FR1) used by the UE 104 / 182 and the cell in which the UE 104 / 182 performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection reestablishment procedure. The primary carrier carries all common and UE-specific control channels and can be a carrier in a licensed frequency (however, this is not always the case). A secondary carrier is a carrier operating on a second frequency (e.g., FR2) that can be configured once an RRC connection is established between the UE 104 and the anchor carrier, and can be used to provide additional radio resources. In some cases, the secondary carrier can be a carrier in an unlicensed frequency. The secondary carrier may contain only necessary signaling information and signals, for example, since both the primary uplink and downlink carriers are typically UE-specific, there may be no UE-specific signaling information and signals in the secondary carrier. This means that different UEs 104 / 182 in a cell may have different downlink primary carriers. The same is true for the uplink primary carrier. The network is able to change the primary carrier of any UE 104 / 182 at any time. This is done, for example, to balance the load on different carriers. Because a "serving cell" (whether a PCell or an SCell) corresponds to a carrier frequency / component carrier on which some base station is communicating, the terms "cell", "serving cell", "component carrier", "carrier frequency", etc. may be used interchangeably.

[0049] For example, still refer to Figure 1 , one of the frequencies utilized by the macrocell base station 102 may be an anchor carrier (or "PCell"), while the other frequencies utilized by the macrocell base station 102 and / or the mmW base station 180 may be supplementary carriers ("Scells"). Simultaneous transmission and / or reception of multiple carriers enables the UE 104 / 182 to significantly increase its data transmission and / or reception rate. For example, two 20 MHz aggregated carriers in a multi-carrier system would theoretically result in a two-fold increase in data rate (i.e., 40 MHz) compared to that achieved with a single 20 MHz carrier.

[0050] exist Figure 1 In the example of FIG. 1 , one or more Earth-orbiting satellite positioning system (SPS) spacecraft (SV) 112 (eg, satellites) may be used as any of the illustrated UEs (for simplicity). Figure 1104). UE104 may include one or more dedicated SPS receivers specifically designed to receive SPS signals 124 to derive geographic location information from SV 112. SPS typically includes a transmitter system (e.g., SV 112) that is positioned so that receivers (e.g., UE104) can determine their positions on or above the earth based at least in part on signals received from the transmitter (e.g., SPS signals 124). Such transmitters typically transmit signals marked with a repetitive pseudo-random noise (PN) code having a set number of chips. Although typically located in SV 112, the transmitter may sometimes be located on a ground-based control station, base station 102, and / or other UE 104.

[0051] The use of the SPS signal 124 may be enhanced by various satellite-based augmentation systems (SBAS) that may be associated with or otherwise capable of use with one or more global and / or regional navigation satellite systems. For example, the SBAS may include (one or more) augmentation systems that provide integrity information, differential corrections, etc., such as the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multifunction Satellite Augmentation System (MSAS), the Global Positioning System (GPS) Assisted Geographic Augmentation Navigation or the GPS and Geographic Augmentation Navigation System (GAGAN), etc. Thus, as used herein, an SPS may include any combination of one or more global and / or regional navigation satellite systems and / or augmentation systems, and the SPS signal 124 may include an SPS, an SPS-like signal, and / or other signals associated with such one or more SPS.

[0052] By leveraging NR's increased data rates and reduced latency, vehicle-to-everything (V2X) communication technology is being implemented to support intelligent transportation system (ITS) applications, such as wireless communication 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 to enable vehicles to perceive their surroundings and communicate that information to other vehicles, infrastructure, and personal mobile devices. This vehicle communication will enable safety, mobility, and environmental advances that current technology cannot provide. Once fully realized, the technology is expected to reduce 80% of collisions involving undamaged vehicles.

[0053] Still reference Figure 1, the wireless communication system 100 may include a plurality of V-UEs 160 that may communicate with a base station 102 via a communication link 120 (e.g., using a Uu interface). The V-UEs 160 may also communicate directly with each other via a wireless side link 162, with a roadside access point 164 (also referred to as a “roadside unit”) via a wireless side link 166, or with a UE 104 via a wireless side link 168. A wireless side link (or simply “side link”) is an adaptation of a core cellular (e.g., LTE, NR) standard that allows direct communication between two or more UEs without communicating through a base station. Side link communications may be unicast or multicast and may be used for device-to-device (D2D) media sharing, V2V communications, V2X communications (e.g., cellular V2X (cV2X) communications, enhanced V2X (eV2X) communications, etc.), emergency assistance applications, etc. One or more of a group of V-UEs 160 utilizing side link communications may be within a geographic coverage area 110 of a 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 otherwise unable 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, where each V-UE 160 transmits to each other V-UE 160 in the group. In some cases, the base station 102 facilitates scheduling resources for sidelink communications. In other cases, sidelink communications are performed between the V-UEs 160 without involving the base station 102.

[0054] In one aspect, the sidelinks 162, 166, 168 can operate on a wireless communication medium of interest that can be shared with other vehicles and / or infrastructure access points and other wireless communications between other RATs. The "medium" can consist of one or more time, frequency, and / or spatial communication resources (e.g., covering one or more channels across one or more carriers) associated with wireless communications between one or more transmitter / receiver pairs.

[0055] In one aspect, the sidelinks 162, 166, 168 may be cV2X links. The first generation of cV2X has been standardized in LTE, and the next generation is expected to be defined in NR. cV2X is a cellular technology that also supports device-to-device communications. In the United States and Europe, cV2X is expected to operate in the authorized ITS bands below 6 GHz (sub-6 GHz). Other bands may be allocated in other countries. Therefore, as a specific example, the medium of interest utilized by the sidelinks 162, 166, 168 may correspond to at least a portion of the authorized ITS band below 6 GHz. However, the present disclosure is not limited to this band or cellular technology.

[0056] In one aspect, the side links 162, 166, 168 can be dedicated short-range communication (DSRC) links. DSRC is a unidirectional or bidirectional short-range to medium-range wireless communication protocol that uses the Wireless Access for Vehicular Environment (WAVE) protocol, also known as IEEE802.11p, for V2V, V2I, and V2P communications. IEEE 802.11p is an approved revision of the IEEE 802.11 standard and operates in the authorized ITS band of 5.9 GHz (5.85-5.925 GHz) in the United States. In Europe, IEEE 802.11p operates in the ITS G5A band (5.875–5.905 MHz). Other bands may be allocated in other countries. The V2V communications briefly described above occur on a safety channel, which in the United States is typically a 10 MHz channel dedicated to safety purposes. The remainder of the DSRC band (with a total bandwidth of 75 MHz) is intended for other services of interest to drivers, such as road rules, toll collection, parking automation, 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 licensed ITS band at 5.9 GHz.

[0057] Alternatively, the medium of interest may correspond to at least a portion of an unlicensed band shared among various RATs. Although different licensed bands have been reserved for certain communication systems (e.g., by government entities such as the Federal Communications Commission (FCC) in the United States), these systems (particularly those employing small cell access points) have recently expanded operations into unlicensed bands, such as the unlicensed national information infrastructure (U-NII) bands used by wireless local area network (WLAN) technologies, particularly the IEEE 802.11x WLAN technology commonly referred to as "Wi-Fi". Example systems of this type include different variants of CDMA systems, TDMA systems, FDMA systems, orthogonal FDMA (OFDMA) systems, single carrier FDMA (SC-FDMA) systems, and the like.

[0058] 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 the V-UEs 160. V2I information received at the V-UEs 160 from one or more roadside access points 164 may include, for example, road rules, parking automation information, etc. V2P communications between V-UEs 160 and UEs 104 may include, for example, information about the location, speed, acceleration, and heading of the V-UEs 160 and the location, speed (e.g., in the case where the UEs 104 are carried by a user on a bicycle), and heading of the UEs 104.

[0059] Note that although Figure 1 Only two of the UEs are shown as V-UEs (V-UE 160), but any of the UEs shown (e.g., UE 104, 152, 182, 190) may be a V-UE. In addition, although only V-UE 160 and a single UE 104 are shown as connected via a side link, Figure 1 Any of the UEs shown in (whether V-UE, P-UE, etc.) may be capable of sidelink communications. In addition, while only UE 182 is described as being capable of beamforming, any of the UEs shown (including V-UE 160) may be capable of beamforming. In the event that V-UE 160 is capable of beamforming, they may beamform toward each other (i.e., toward other V-UE 160), toward roadside access points 164, toward other UEs (e.g., UE 104, 152, 182, 190), etc. Thus, in some cases, V-UE 160 may utilize beamforming on sidelinks 162, 166, and 168.

[0060] The wireless communication system 100 may also include one or more UEs, such as UE 190, that are indirectly connected to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links. Figure 1In the example of FIG. 1 , UE 190 has a D2D P2P link 192, where one of UEs 104 is connected to one of base stations 102 (e.g., through which UE 190 can indirectly obtain cellular connectivity), and has a D2D P2P link 194, where WLAN STA 152 is connected to WLAN AP 150 (through which UE 190 can indirectly obtain WLAN-based Internet connectivity). In the example, D2D P2P links 192 and 194 can be connected using any well-known D2D RAT (such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), As another example, the D2D P2P links 192 and 194 may be side links, as described above with reference to the side link links 162, 166, and 168.

[0061] Figure 2A An example wireless network architecture 200 is shown. For example, the 5GC 210 (also referred to as the Next Generation Core (NGC)) can be functionally viewed as a control plane (C-plane) function 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and a user plane (U-plane) function 212 (e.g., UE gateway function, access to data networks, IP routing, etc.), which can operate in conjunction to form a core network. The user plane interface (NG-U) 213 and the control plane interface (NG-C) 215 connect the gNB 222 to the 5GC 210, specifically to the user plane function 212 and the control plane function 214, respectively. In another configuration, the ng-eNB 224 can 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. In addition, the ng-eNB 224 can communicate directly with the gNB 222 via the 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 ng-eNBs 224 and gNBs 222. Either (or both) the gNB 222 or the ng-eNB 224 may communicate with one or more UEs 204 (e.g., any UE described herein).

[0062] Another optional aspect may include a location server 230 that can communicate with the 5GC 210 to provide location assistance for (one or more) UEs 204. The location server 230 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternatively, each can correspond to a single server. The location server 230 can be configured to support one or more location services for the UE 204, which can be connected to the location server 230 via the core network, the 5GC 210, and / or via the Internet (not shown). In addition, the location server 230 can be integrated into a component of the core network, or alternatively can be external to the core network (e.g., a third-party server, such as an original equipment manufacturer (OEM) server or a service server).

[0063] Figure 2B Another exemplary wireless network structure 250 is shown. 5GC 260 (which may correspond to Figure 2AThe 5GC 210 in the UE 200 may be functionally viewed as a control plane function provided by an access and mobility management function (AMF) 264 and a user plane function provided by a user plane function (UPF) 262, which may operate in conjunction 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, transmission of session management (SM) messages between one or more UEs 204 (e.g., any UE described herein) and a session management function (SMF) 266, a transparent proxy service for routing SM messages, access authentication and access authorization, transmission of short message service (SMS) messages between the UE 204 and a short message service function (SMSF) (not shown), and a security anchor function (SEAF). The AMF 264 also interacts with an authentication server function (AUSF) (not shown) and the UE 204, and receives an intermediate key established as a result of the UE 204 authentication process. In the case of authentication based on the UMTS (Universal Mobile Telecommunications System) User Identity Module (USIM), the AMF 264 retrieves security material from the AUSF. The functions of the AMF 264 also include security context management (SCM). The SCM receives keys from the SEAF, which it uses to derive access network-specific keys. The functions of the AMF 264 also include location service management for regulatory services, transmission of location service messages between the UE 204 and the Location Management Function (LMF) 270 (which serves as the location server 230), transmission of location service messages between the NG-RAN 220 and the LMF 270, allocation of Evolved Packet System (EPS) bearer identifiers for interaction with EPS, and notification of UE 204 mobility events. In addition, the AMF 264 also supports functions for non-3GPP (Third Generation Partnership Project) access networks.

[0064] The functions of UPF 262 include: acting as an anchor point for intra-RAT / inter-RAT mobility (when applicable), acting as an external protocol data unit (PDU) session point for interconnecting with a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) processing for the user plane (e.g., uplink / downlink rate enforcement, reflective QoS marking in downlink), uplink traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in uplink and downlink, downlink packet buffering and downlink data notification triggering, and sending and forwarding of one or more "end markers" to the source RAN node. UPF 262 can also support the transmission of location service messages on the user plane between UE 204 and a location server such as SLP 272.

[0065] The functions of SMF 266 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering at UPF 262 to route traffic to the correct destination, control of part of policy enforcement and QoS, and downlink data notification. The interface through which SMF 266 communicates with AMF 264 is called the N11 interface.

[0066] Another optional aspect may include an LMF 270 that can communicate with the 5GC 260 to provide location assistance for the UE 204. The LMF 270 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternatively, can each correspond to a single server. The LMF 270 can be configured to support one or more location services for the UE 204, which can be connected to the LMF 270 via the core network, the 5GC 260, and / or via the Internet (not shown). The SLP 272 can support similar functionality to the LMF 270, but the LMF 270 can communicate with the AMF 264, the NG-RAN 220, and the UE 204 via the control plane (e.g., using interfaces and protocols intended to transmit signaling messages rather than voice or data), and the SLP 272 can communicate with the UE 204 and external clients ( Figure 2B ) communications (e.g., using protocols designed to carry voice and / or data, such as the Transmission Control Protocol (TCP) and / or IP).

[0067] The user plane interface 263 and the control plane interface 265 connect the 5GC 260 (specifically, 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 the ng-eNB(s) 224 and the AMF 264 is referred to as the "N2" interface, while the interface between the gNB(s) 222 and / or the ng-eNB(s) 224 and the UPF 262 is referred to as the "N3" interface. The gNB(s) 222 and / or the ng-eNB(s) 224 of the NG-RAN 220 may communicate directly with each other via a backhaul connection 223 referred to as an "Xn-C" interface. One or more of the gNBs 222 and / or the ng-eNBs 224 may communicate with one or more UEs 204 via a wireless interface referred to as a "Uu" interface.

[0068] The functionality of the gNB 222 is divided between the gNB Central Unit (gNB-CU) 226 and one or more gNB Distributed Units (gNB-DU) 228. The interface 232 between the gNB-CU 226 and one or more gNB-DUs 228 is referred to as the "F1" interface. The gNB-CU 226 is a logical node that includes base station functions for transmitting user data, mobility control, radio access network sharing, positioning, session management, etc., in addition to those functions specifically assigned to (one or more) gNB-DUs 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 may support one or more cells, while one cell is supported by only one gNB-DU 228. Therefore, the UE 204 communicates with the gNB-CU 226 via the RRC, SDAP, and PDCP layers and communicates with the gNB-DU 228 via the RLC, MAC, and PHY layers.

[0069] Figure 3An example of a wireless communication system 300 that supports wireless unicast sidelink establishment according to aspects of the present disclosure is shown. In some examples, the wireless communication system 300 can implement aspects of the wireless communication systems 100, 200, and 250. The wireless communication system 300 can include a first UE 302 and a second UE 304, which can be examples of any UE described herein. As a specific example, the UEs 302 and 304 can correspond to Figure 1 V-UE 160 in the D2D P2P link 192 Figure 1 UE 190 and UE 104 in, or Figure 2A and Figure 2B UE 204 in.

[0070] exist Figure 3 In the example of , UE 302 may attempt to establish a unicast connection via a side link with UE 304, which side link may be a V2X side link between UE 302 and UE 304. As a specific example, the established side link connection may correspond to Figure 1 The sidelink connection may be established in an omni frequency range (e.g., FR1) and / or in a mmW frequency range (e.g., FR2). In some cases, UE 302 may be referred to as an initiating UE that initiates a sidelink connection procedure, and UE 304 may be referred to as a target UE that is targeted by the initiating UE for the sidelink connection procedure.

[0071] In order to establish a unicast connection, access stratum (AS) (a functional layer in the UMTS and LTE protocol stacks between the RAN and the UE, responsible for transmitting data over a wireless link and managing radio resources, and part of Layer 2) parameters may be configured and negotiated between the UE 302 and the UE 304. For example, a transmission and reception capability match may be negotiated between the UE 302 and the UE 304. Each UE may have different capabilities (e.g., transmission and reception, 64 quadrature amplitude modulation (QAM), transmission diversity, carrier aggregation (Ca), supported (one or more) communication bands, etc.). In some cases, different services may be supported in the upper layers of the corresponding protocol stacks of the UE 302 and the UE 304. In addition, a security association for a unicast connection may be established between the UE 302 and the UE 304. Unicast services may benefit from link-level security protection (e.g., integrity protection). The security requirements of different wireless communication systems may be different. For example, V2X and Uu systems may have different security requirements (e.g., Uu security does not include confidentiality protection). Additionally, IP configuration (eg, IP version, address, etc.) may be negotiated for a unicast connection between UE 302 and UE 304 .

[0072] In some cases, UE 304 may create a service announcement (e.g., a service capability message) to be sent over a cellular network (e.g., cV2X) to assist in establishing a sidelink connection. Typically, UE 302 may identify and locate candidates for sidelink communication based on unencrypted basic service messages (BSMs) broadcast by nearby UEs (e.g., UE 304). The BSM may include location information, security and identity information, and vehicle information (e.g., speed, maneuverability, size, etc.) of the corresponding UE. However, for different wireless communication systems (e.g., D2D or V2X communications), the discovery channel may be configured to enable UE 302 to detect (one or more) BSMs. Therefore, the service announcements (e.g., discovery signals) sent by UE 304 and other nearby UEs may be upper layer signals and broadcast (e.g., in NR sidelink broadcasts). In some cases, UE 304 may include one or more parameters of itself in the service announcement, including connection parameters and / or capabilities it possesses. UE 302 may then monitor and receive the broadcasted service announcements to identify potential UEs for corresponding sidelink connections. In some cases, UE 302 may identify potential UEs based on the capabilities indicated by each UE in their respective service announcements.

[0073] The service announcement may include information used to help UE 302 (eg, or any initiating UE) identify the UE that sent the service announcement. Figure 3 304 in the example of ). For example, the service announcement may include channel information on which direct communication requests may be sent. In some cases, the channel information may be RAT-specific (e.g., LTE or NR-specific) and may include a resource pool in which the UE 302 sends the communication request. In addition, if the destination address is different from the current address (e.g., the address of the streaming provider or the address of the UE sending the service announcement), the service announcement may include a specific destination address of the UE (e.g., a layer 2 destination address). The service announcement may also include a network or transport layer on which the UE 302 sends the communication request. For example, the network layer (also referred to as "layer 3" or "L3") or the transport layer (also referred to as "layer 4" or "L4") may indicate the port number of the application for the UE to send 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. In addition, the service announcement may include a protocol for certificate establishment and parameters related to QoS.

[0074] In identifying potential sidelink connection targets ( Figure 3 After that, the initiator UE ( Figure 3304) can send a connection request 315 to the identified target UE 304. In some cases, the connection request 315 can be a first RRC message (e.g., an "RRCDirectConnectionSetupRequest" message) sent by the UE 302 to request a unicast connection with the UE 304. For example, the unicast connection can utilize the PC5 interface for the sidelink, and the connection request 315 can be an RRC connection establishment request message. In addition, the UE 302 can use the sidelink signaling radio bearer 305 to transmit the connection request 315.

[0075] After receiving the connection request 315, the UE 304 may determine whether to accept or reject the connection request 315. The UE 304 may make this determination based on the transmit / receive capabilities, the ability to accommodate a unicast connection on the sidelink, the specific service indicated for the unicast connection, the content to be sent via the unicast connection, or a combination thereof. For example, if the UE 302 wants to use the first RAT to send or receive data, but the UE 304 does not support the first RAT, the UE 304 may reject the connection request 315. Additionally or alternatively, the UE 304 may reject the connection request 315 based on the inability to accommodate a unicast connection via the sidelink due to limited radio resources, scheduling issues, etc. Therefore, the UE 304 may send an indication of whether to accept or reject the request in the connection response 320. Similar to the UE 302 and the connection request 315, the UE 304 may use the sidelink signaling radio bearer 310 to transmit the connection response 320. Additionally, the connection response 320 may be a second RRC message (eg, a “RRCDirectConnectionResponse” message) sent by the UE 304 in response to the connection request 315 .

[0076] In some cases, the sidelink signaling radio bearers 305 and 310 may be the same sidelink signaling radio bearer or may be separate sidelink signaling radio bearers. Therefore, a radio link control (RLC) layer acknowledgement mode (AM) may be used for the sidelink signaling radio bearers 305 and 310. A UE supporting unicast connections may monitor on a logical channel associated with the sidelink signaling radio bearer. In some cases, the AS layer (i.e., Layer 2) may deliver information directly through RRC signaling (e.g., control plane) rather than the V2X layer (e.g., data plane).

[0077] If the connection response 320 indicates that the UE 304 accepts the connection request 315, the UE 302 may then send a connection setup 325 message on the sidelink signaling radio bearer 305 to indicate that the unicast connection setup is complete. In some cases, the connection setup 325 may be a third RRC message (e.g., an "RRCDirectConnectionSetupComplete" message). Each of the connection request 315, the connection response 320, and the connection setup 325 may use basic capabilities when transmitted from one UE to another UE to enable each UE to receive and decode the corresponding transmission (e.g., an RRC message).

[0078] In addition, an identifier may be used for each of the connection request 315, the connection response 320, and the connection establishment 325. For example, the identifier may indicate which UE 302 / 304 is sending which message and / or which UE 302 / 304 the message is intended for. For physical (PHY) layer channels, RRC signaling and any subsequent data transmission may use the same identifier (e.g., Layer 2 ID). However, for logical channels, the identifiers used for RRC signaling and for data transmission may be separate. For example, on a logical channel, RRC signaling and data transmission may be treated differently and have different confirmation (ACK) feedback messages. In some cases, for RRC messages, a physical layer ACK may be used to ensure that the corresponding message is correctly sent and received.

[0079] One or more information elements may be included in the connection request 315 and / or the connection response 320 for UE 302 and / or UE 304, respectively, to enable negotiation of corresponding AS layer parameters for unicast connection. For example, UE 302 and / or UE 304 may include a packet data convergence protocol (PDCP) parameter in the corresponding unicast connection establishment message to set the PDCP context for the unicast connection. In some cases, the PDCP context may indicate whether PDCP duplication is used for the unicast connection. In addition, UE 302 and / or UE 304 may include an RLC parameter when establishing a unicast connection to set the RLC context for the unicast connection. For example, the RLC context may indicate whether AM (e.g., using a reordering timer (t-reordering)) or an unacknowledged mode (UM) is used for the RLC layer of the unicast communication.

[0080] In addition, UE 302 and / or UE 304 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 the HARQ feedback scheme, carrier aggregation, or a combination thereof for a unicast connection. In addition, UE 302 and / or UE 304 may include PHY layer parameters to set up a PHY layer context for a unicast connection when establishing a unicast connection. For example, the PHY layer context may indicate a transport format for a unicast connection (unless a transport profile is included for each UE 302 / 304) and a radio resource configuration (e.g., bandwidth part (BWP), parameter set, etc.). These information elements may support different frequency range configurations (e.g., FR1 and FR2).

[0081] In some cases, a security context may also be set for the unicast connection (e.g., after the connection establishment 325 message has been sent). Before a security association (e.g., a security context) is established between UE 302 and UE 304, the sidelink signaling radio bearers 305 and 310 may not be protected. After the security association is established, the sidelink signaling radio bearers 305 and 310 may be protected. Therefore, the security context may enable secure data transmission through the unicast connection and the sidelink signaling radio bearers 305 and 310. In addition, 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 an upper layer control protocol running after RRC signaling is established (e.g., after the unicast connection is established). As described above, UE 304 may decide whether to accept or reject the connection request 315 based on a specific service indicated for the unicast connection and / or content to be sent over the unicast connection (e.g., upper layer information). Specific services and / or content may also be indicated by an upper layer control protocol running after RRC signaling is established.

[0082] After establishing the unicast connection, UE 302 and UE 304 may communicate via side link 330 using the unicast connection, wherein side link data 335 is transmitted between the two UEs 302 and 304. Side link 330 may correspond to Figure 1162 and / or 168 in the side link 330. In some cases, the side link data 335 may include an RRC message transmitted between the two UEs 302 and 304. In order to maintain the unicast connection on the side link 330, UE 302 and / or UE 304 may send a keep-alive message (e.g., a "RRCDirectLinkAlive" message, a fourth RRC message, etc.). In some cases, the keep-alive message may be triggered periodically or on demand (e.g., event triggered). Therefore, the triggering and transmission of the keep-alive message may be called by UE 302 or by both UE 302 and UE 304. Additionally or alternatively, a MAC control element (CE) (e.g., defined by the side link 330) may be used to monitor the state of the unicast connection on the side link 330 and maintain the connection. When the unicast connection is no longer needed (e.g., UE 302 travels far enough from UE 304), UE 302 and / or UE 304 may start a release process to stop the unicast connection through the side link 330. Therefore, subsequent RRC messages may not be transmitted between UE 302 and UE 304 over the unicast connection.

[0083] Figure 4A , Figure 4B and Figure 4C 4 shows a network entity 406 (which may correspond to or embody any network function described herein, including location server 230 and LMF 270, or may alternatively be independent of UE 402, which may correspond to any UE described herein), base station 404 (which may correspond to any base station described herein), and network entity 406 (which may correspond to or embody any network function described herein, including location server 230 and LMF 270). Figure 2A and Figure 2B 220 and / or 5GC 210 / 260 infrastructure, such as a dedicated network) to support file transfer operations as taught herein. It should be understood that these components can be implemented in different types of devices in different embodiments (e.g., in an ASIC, in a system on a chip (SoC), etc.). The components shown may also be incorporated into other devices in the communication system. For example, other devices in the system may include components similar to those described to provide similar functionality. In addition, a given device may include one or more of the components. For example, a device may include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0084] UE 402 and base station 404 each include at least one wireless wide area network (WWAN) transceiver 410 and 450, respectively, to provide means (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for suppressing transmission, etc.) for communicating via one or more wireless communication networks (not shown), such as NR networks, LTE networks, GSM networks, etc. WWAN transceivers 410 and 450 may be connected to one or more antennas 416 and 456, respectively, for communicating with other network nodes, such as other UEs, access points, base stations (e.g., eNBs, gNBs), etc., via at least one designated RAT (e.g., NR, LTE, GSM, etc.) over a wireless communication medium of interest (e.g., some set of time / frequency resources in a particular spectrum). Depending on the designated RAT, the WWAN transceivers 410 and 450 may be configured differently to transmit and encode signals 418 and 458 (e.g., messages, indications, information, etc.), respectively, and conversely, to receive and decode signals 418 and 458 (e.g., messages, indications, information, pilots, etc.), respectively. Specifically, the WWAN transceivers 410 and 450 include one or more transmitters 414 and 454, respectively, to transmit and encode signals 418 and 458, respectively, and one or more receivers 412 and 452, respectively, to receive and decode signals 418 and 458, respectively.

[0085] UE 402 and base station 404, at least in some cases, each also include at least one short-range wireless transceiver 420 and 460, respectively. Short-range wireless transceivers 420 and 460 can be connected to one or more antennas 426 and 466, respectively, and provide for communicating via at least one designated RAT (e.g., WiFi, LTE-D, The short-range wireless transceivers 420 and 460 include components (e.g., components for sending, components for receiving, components for measuring, components for tuning, components for suppressing sending, etc.) for communicating with other network nodes such as other UEs, access points, base stations, etc. (e.g., PC5, dedicated short-range communication (DSRC), wireless access for vehicular environment (WAVE), near field communication (NFC), etc.). Depending on the specified RAT, the short-range wireless transceivers 420 and 460 can be configured differently to respectively send and encode signals 428 and 468 (e.g., messages, indications, information, etc.), and conversely, to respectively receive and decode signals 428 and 468 (e.g., messages, indications, information, pilots, etc.). Specifically, the short-range wireless transceivers 420 and 460 include one or more transmitters 424 and 464, respectively, for sending and encoding signals 428 and 468, respectively, and one or more receivers 422 and 462, respectively, for receiving and decoding signals 428 and 468, respectively. As a specific example, the short-range wireless transceivers 420 and 460 may be WiFi transceivers, Transceiver, and / or transceiver, NFC transceiver or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceiver.

[0086] A transceiver circuit system including at least one transmitter and at least one receiver may include an integrated device (e.g., a transmitter circuit and a receiver circuit embodied as a single communication device) in some embodiments, may include a separate transmitter device and a separate receiver device in some embodiments, or may be implemented in other ways in other embodiments. In one aspect, the transmitter may include or be coupled to multiple antennas (e.g., antennas 416, 426, 456, 466), such as an antenna array, which allows the corresponding device to perform transmit "beamforming", as described herein. Similarly, the receiver may include or be coupled to multiple antennas (e.g., antennas 416, 426, 456, 466), such as an antenna array, which allows the corresponding device to perform receive beamforming, as described herein. In one aspect, the transmitter and receiver may share the same multiple antennas (e.g., antennas 416, 426, 456, 466) so that the corresponding device can only receive or transmit at a given time, rather than receiving or transmitting both at the same time. The wireless communication devices of the UE 402 and / or the base station 404 (eg, one or both of the transceivers 410 and 420 and / or 450 and 460) may also include a network listening module (NLM) or the like for performing various measurements.

[0087] UE 402 and base station 404 also include satellite positioning system (SPS) receivers 430 and 470, at least in some cases. SPS receivers 430 and 470 can be connected to one or more antennas 436 and 476, respectively, and can provide components for receiving and / or measuring SPS signals 438 and 478, respectively, such as 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. SPS receivers 430 and 470 can include any suitable hardware and / or software for receiving and processing SPS signals 438 and 478, respectively. SPS receivers 430 and 470 request information and operations from other systems as appropriate, and use measurements obtained by any suitable SPS algorithm to perform calculations necessary to determine the location of UE 402 and base station 404.

[0088] The base station 404 and the network entity 406 each include at least one network interface 480 and 490, respectively, thereby providing components for communicating with other network entities (e.g., components for sending, components for receiving, etc.). For example, the network interfaces 480 and 490 (e.g., one or more network access ports) can be configured to communicate with one or more network entities via a wired or wireless backhaul connection. In some aspects, the network interfaces 480 and 490 can be implemented as transceivers configured to support wired or wireless signal communications. Such communications can involve, for example, sending and receiving messages, parameters, and / or other types of information.

[0089] In one aspect, at least one WWAN transceiver 410 and / or at least one short-range wireless transceiver 420 may form a (wireless) communication interface of UE 402. Similarly, at least one WWAN transceiver 450, at least one short-range wireless transceiver 460 and / or at least one network interface 480 may form a (wireless) communication interface of base station 404. Likewise, at least one network interface 490 may form a (wireless) communication interface of network entity 406. Various wireless transceivers (e.g., transceivers 410, 420, 450, and 460) and wired transceivers (e.g., network interfaces 480 and 490) may generally be characterized as at least one transceiver, or alternatively, as at least one communication interface. Therefore, whether a particular transceiver or communication interface is associated with a wired or wireless transceiver or communication interface, respectively, may be inferred from the type of communication performed (e.g., backhaul communications between network devices or servers will generally involve signaling via at least one wired transceiver).

[0090] UE 402, base station 404, and network entity 406 also include other components that can be used in conjunction with the operations disclosed herein. UE 402, base station 404, and network entity 406 include at least one processor 432, 484, and 494, respectively, for providing functions related to, for example, wireless communication and for providing other processing functions. Processors 432, 484, and 494 can therefore provide components for processing, such as components for determining, components for calculating, components for receiving, components for sending, components for indicating, etc. In one aspect, processors 432, 484, and 494 can include, for example, at least one general-purpose processor, a multi-core processor, a central processing unit (CPU), an ASIC, a digital signal processor (DSP), a field programmable gate array (FPGA), other programmable logic devices or processing circuit systems, or various combinations thereof.

[0091] UE 402, base station 404, and network entity 406 include memory circuitry implementing memory components 440, 486, and 496, respectively (e.g., each including a memory device), for maintaining information (e.g., information indicating reserved resources, thresholds, parameters, etc.). Memory components 440, 486, and 496 may thus provide means for storing, means for retrieving, means for maintaining, etc. In some cases, UE 402, base station 404, and network entity 406 may include side link managers 442, 488, and 498, respectively. Side link managers 442, 488, and 498 may be hardware circuits that are part of or coupled to processors 432, 484, and 494, respectively, which when executed cause UE 402, base station 404, and network entity 406 to perform the functions described herein. In other aspects, the side link managers 442, 488, and 498 can be external to the processors 432, 484, and 494 (e.g., as part of a modem processing system, integrated with another processing system, etc.). Alternatively, the side link managers 442, 488, and 498 can be memory modules stored in the memory components 440, 486, and 496, respectively, which, when executed by the processors 432, 484, and 494 (or a modem processing system, another processing system, etc.), cause the UE 402, the base station 404, and the network entity 406 to perform the functions described herein. Figure 4A Possible locations for the side link manager 442 are shown, which may be, for example, part of at least one WWAN transceiver 410, the memory component 440, the at least one processor 432, or any combination thereof, or may be a standalone component. Figure 4B Possible locations for the side link manager 488 are shown, which may be, for example, part of at least one WWAN transceiver 450, the memory component 486, at least one processor 484, or any combination thereof, or may be a stand-alone component. Figure 4C Possible locations for the side-link manager 498 are shown, which may be, for example, part of at least one network interface 490, memory component 496, at least one processor 494, or any combination thereof, or may be a stand-alone component.

[0092] UE 402 may include one or more sensors 444 coupled to at least one processor 432 to provide a means for sensing or detecting movement and / or orientation information independent of motion data derived from signals received by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, and / or SPS receiver 430. As an example, (one or more) sensors 444 may include an accelerometer (e.g., a microelectromechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), and / or any other type of motion detection sensor. In addition, (one or more) sensors 444 may include multiple different types of devices and combine their outputs to provide motion information. For example, (one or more) sensors 444 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.

[0093] In addition, the UE 402 includes a user interface 446, which provides means for providing indications to the user (e.g., audible and / or visual indications) and / or for receiving user input (e.g., when the user actuates a sensing device such as a keyboard, touch screen, microphone, etc.). Although not shown, the base station 404 and the network entity 406 may also include a user interface.

[0094] Referring to the at least one processor 484 in more detail, in a downlink, IP packets from the network entity 406 may be provided to the at least one processor 484. The at least one processor 484 may implement functions of an RRC layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. At least one processor 484 may provide: RRC layer functions associated with broadcasting of 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 measurement configuration for UE measurement reporting; PDCP layer functions associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions associated with transmission of upper layer PDUs, error correction through automatic repeat request (ARQ), concatenation, segmentation and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization.

[0095] The transmitter 454 and the receiver 452 may implement layer 1 (L1) functions associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection on the transmission channel, forward error correction (FEC) encoding / decoding of the transmission channel, interleaving, rate matching, mapping to physical channels, modulation / demodulation of physical channels, and MIMO antenna processing. The transmitter 454 processes the mapping to the signal constellation 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., a pilot) in the time and / or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM symbol stream is spatially precoded to produce multiple spatial streams. The channel estimate from the channel estimator may be used to determine the coding and modulation schemes, as well as for spatial processing. The channel estimate may be derived from a reference signal and / or channel condition feedback sent by the UE 402. Each spatial stream may then be provided to one or more different antennas 456. The transmitter 454 may modulate an RF carrier with a corresponding spatial stream for transmission.

[0096] At the UE 402, the receiver 412 receives the signal through its corresponding (one or more) antennas 416. The receiver 412 recovers the information modulated onto the RF carrier and provides the information to at least one processor 432. The transmitter 414 and the receiver 412 implement layer 1 functions associated with various signal processing functions. The receiver 412 can perform spatial processing on the information to recover any spatial stream destined for the UE 402. If multiple spatial streams are destined for the UE 402, they can be combined into a single OFDM symbol stream by the receiver 412. The receiver 412 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. By determining the most likely signal constellation point sent by the base station 404, the symbols on each subcarrier and the reference signal can be recovered and demodulated. These soft decisions can 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 sent on the physical channel by the base station 404. The data and control signals are then provided to at least one processor 432, which implements Layer 3 (L3) and Layer 2 (L2) functionality.

[0097] In the uplink, at least one processor 432 provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets from the core network. At least one processor 432 is also responsible for error detection.

[0098] Similar to the functions described in conjunction with the downlink transmission of the base station 404, at least one processor 432 provides: RRC layer functions associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functions associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functions associated with transmission of upper layer PDUs, error correction through ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs into transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), priority processing, and logical channel prioritization.

[0099] Channel estimates derived by the channel estimator from a reference signal or feedback sent by the base station 404 may be used by the transmitter 414 to select appropriate coding and modulation schemes and to assist in spatial processing. The spatial streams generated by the transmitter 414 may be provided to different antenna(s) 416. The transmitter 414 may modulate an RF carrier with a corresponding spatial stream for transmission.

[0100] The uplink transmission is processed at the base station 404 in a manner similar to that described in conjunction with the receiver functionality at the UE 402. The receiver 452 receives the signal through its corresponding antenna(s) 456. The receiver 452 recovers the information modulated onto the RF carrier and provides the information to the at least one processor 484.

[0101] In the uplink, at least one processor 484 provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover IP packets from UE 402. IP packets from at least one processor 484 may be provided to the core network. At least one processor 484 is also responsible for error detection.

[0102] For convenience, UE 402, base station 404 and / or network entity 406 may Figure 4A , Figure 4B and Figure 4C 1 and 2. The schematic diagram of the embodiment of the present invention is shown as including various components that can be configured according to various examples described herein. However, it should be understood that the components shown may have different functions in different designs.

[0103] Various components of the UE 402, base station 404, and network entity 406 may communicate with each other via data buses 434, 482, and 492, respectively. In one aspect, the data buses 434, 482, and 492 may form or be part of a communication interface for the UE 402, base station 404, and network entity 406, respectively. For example, where different logical entities are implemented in the same device (e.g., gNB and location server functions incorporated into the same base station 404), the data buses 434, 482, and 492 may provide communication between them.

[0104] Figure 4A , Figure 4B and Figure 4C The components of can be implemented in various ways. In some embodiments, Figure 4A , Figure 4B and Figure 4CThe components may be implemented in one or more circuits (e.g., one or more processors and / or one or more ASICs (which may include one or more processors)). Here, each circuit may use and / or combine at least one memory component to store information or executable code used by the circuit to provide the functionality. For example, some or all of the functions represented by blocks 410 to 446 may be implemented by the processor and (one or more) memory components of UE 402 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). Similarly, some or all of the functions represented by blocks 450 to 488 may be implemented by the processor and (one or more) memory components of base station 404 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). In addition, some or all of the functions represented by blocks 490 to 498 may be implemented by the processor and (one or more) memory components of network entity 406 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). For simplicity, various operations, actions and / or functions are described herein as being performed by "UE", "by base station", "by network entity", etc. However, as will be understood, such operations, actions and / or functions may actually be performed by a specific component or combination of components of the UE 402, base station 404, network entity 406, etc., such as processors 432, 484, 494, transceivers 410, 420, 450 and 460, memory components 440, 486 and 496, side link managers 442, 488 and 498, etc.

[0105] In some designs, the network entity 406 may be implemented as a core network component. In other designs, the network entity 406 may be distinct from a network operator or operation of a cellular network infrastructure (e.g., NG RAN 220 and / or 5GC 210 / 260). For example, the network entity 406 may be a component of a dedicated network that may be configured to communicate with the UE 402 via the base station 404 or independently of the base station 404 (e.g., via a non-cellular communication link such as WiFi).

[0106] As described above, sidelink communications between UEs may employ beamforming at mmW or near mmW frequencies, for example, to increase data transfer rates between UEs. In addition to microwave frequencies (e.g., below 6 GHz or in the FR1 band), the use of mmW frequencies may also be supported for sidelink communications, such as group discovery messages. Figure 5 5 is an example diagram 500 showing an example UE 502 (which may correspond to any UE described herein) communicating with an example UE 504 (which may correspond to any UE described herein) in accordance with various aspects of the present disclosure. UEs 502 and 504 may be members of a sidelink communication group and may be attempting to establish a sidelink between them (e.g., Figure 1 The side link 162 or 168 in Figure 3 330 in the side chain). Figure 5 , UE 502 may transmit beamformed signals to UE 504 on one or more transmit beams 502a, 502b, 502c, 502d, 502e, 502f, 502g, 502h. For example, where UE 502 utilizes a single antenna array to perform beamforming toward UE 504, UE 502 may perform "beam scanning" by transmitting first beam 502a, then beam 502b, and so on until finally transmitting beam 502h. Alternatively, UE 502 may transmit beams 502a-502h in a pattern, such as beam 502a, then beam 502h, then beam 502b, then beam 502g, and so on. Where UE 502 utilizes multiple antenna arrays to perform beamforming toward UE 504, each antenna array may perform beam scanning of a subset of beams 502a-502h. Alternatively, each of the beams 502a-502h may correspond to a single antenna or an antenna array.

[0107] UE 504 may receive beamformed signals from UE 502 on one or more receive beams 504a, 504b, 504c, 504d. Note that for simplicity, depending on which of UE 502 and UE 504 is transmitting and which is receiving, Figure 5 The beams shown in 504 represent transmit beams or receive beams. Thus, UE 504 can transmit beamformed signals to UE 502 on one or more of beams 504a-504d, and UE 502 can receive beamformed signals from UE 504 on one or more of beams 502a-502h.

[0108] UE 502 and UE 504 may perform beam training to determine the best receive and transmit beams for each of UE 502 and UE 504. For example, depending on environmental conditions and other factors, UE 502 and UE 504 may determine that the best transmit and receive beams are 502d and 504b, respectively, or beams 502e and 504c, respectively. The direction of the best transmit beam for UE 502 may be the same as or different from the direction of the best receive beam, and similarly, the direction of the best receive beam for UE 504 may be the same as or different from the direction of the best transmit beam.

[0109] UE 502 may transmit a reference signal to UE 504 on multiple beams, each with a different weight. The different weights of the beams will result in different received signal strengths (e.g., RSRP, RSRQ, SINR, etc.) at UE 504. In addition, for a transmit beam that is farther from a line of sight (LOS) path between UE 502 and UE 504, a channel energy response (CER) will be less than a channel energy response (CER) for a transmit beam that is closer to the LOS path. Likewise, the received signal strength of a transmit beam that is farther from the LOS path will be lower than the received signal strength of a transmit beam that is closer to the LOS path.

[0110] exist Figure 5 In the example of , the LOS path between UE 502 and UE 504 is represented as LOS path 510. If UE 502 transmits a reference signal to UE 504 on beams 502c, 502d, 502e, transmit beam 502d is optimally aligned with LOS path 510, while transmit beams 502c and 502e are not. Therefore, beam 502d will have a stronger CER and a higher received signal strength than beams 502c and 502e. UE 504 may report the CER and received signal strength of each measured transmit beam to UE 502, or alternatively, the identity of the transmit beam with the strongest CER and the highest received signal strength.

[0111] For sidelink communications between two or more UEs, it is sometimes necessary for the transmitting UE to increase or decrease its transmit power to improve the audibility of the (one or more) transmitted signals at the (one or more) receiving UEs. This is called transmit power control (TPC). The transmit power can be increased to meet a threshold signal strength at the receiver, or reduced to minimize interference with other transmitters using the spectrum. There are two types of transmit power control, open loop and closed loop. In open loop transmit power control, the transmitting UE determines its transmit power using its own power setting algorithm. There is no feedback input from the receiver. In closed loop transmit power control, the transmitting UE uses feedback from (one or more) receiving UEs to determine its transmit power. In some cases, the receiving UE may specifically request a certain transmit power. Open loop transmit power control may be used during connection establishment, before the (one or more) receiving UEs can provide feedback to the transmitting UE. Once the sidelink has been established (e.g., such as Figure 3 As shown), closed-loop power control can be used.

[0112] As described above, a UE group (e.g., Figure 1 V-UE 160, Figure 2A-2B UE 204 in Figure 3 UE 302 and 304 in Figure 5UE 502 and 504 in the example) can be connected via a side link (e.g., Figure 1 The side link 162 or 168 in Figure 3 330) communications in the sidelink group. If closed-loop / open-loop transmit power control is adopted for the sidelink group communication, the UEs in the group determine (and track) the transmit power that enables them to communicate with other UEs in the group. Typically, the active (transmitting and / or receiving) group members may or may not be known to all UEs in the group. Specifically, as in the case of a closed group, the active group members may be known to all UEs in the group. Alternatively, in the case of an open group, the active group members may not be known to all UEs in the group. As a further alternative, the active group members may be known only to the group leader (i.e., one of the UEs in the sidelink communication group), which may be the case in both open and closed groups.

[0113] Members of a sidelink communication group may join and exit the group at different times. If the group is a closed group (meaning that the group members are known to all UEs in the group), the UEs that other members join or exit the group are signaled, and in response, transmit power control for group communications among the updated set of group members may be re-evaluated.

[0114] Group communication within a sidelink communication group may employ only NACK feedback, or no HARQ feedback at all, since ACK or NACK from each group member may use considerable resource overhead (especially for large groups). In this case, when a group member sends a message to other group members, it assumes that the message has been received (unless it receives a NACK in the case of NACK feedback). Given that the group members have performed the transmit power control process with the other members of the group, they can reasonably assume that the message will be received by the other group members.

[0115] However, a problem with sidelink group communication using transmit power control is how to detect whether a group member is no longer able to receive messages from one or more other group members, such as when a member is suddenly blocked. For example, in the case where member UEs are using beamforming to communicate with each other (as described above with reference to Figure 5As discussed above, beams may become "blocked" due to UE mobility (e.g., moving behind an obstacle) or other environmental factors (e.g., high interference due to transmissions from newly appearing devices). This is particularly problematic when there are no distinct ACK transmissions from each group member for the group communication. That is, due to the transmit power control process, the transmitting group member assumes that the other group members will receive its messages without an ACK, and this is often the case. However, if a member is blocked relative to the transmitter, it will not receive the group communication, and the blocked member will have no way of knowing that it missed a message or notifying the transmitter that it has missed a message (e.g., via a NACK). Likewise, since the transmitter does not expect an ACK in response to its message, it will not know that one of its messages was not received.

[0116] Therefore, the present disclosure provides a method for enabling a group leader and / or a base station to detect whether all group member UEs are well connected, and if not, triggering transmit power control and / or beam improvement or beam failure recovery procedures for one or more group member UEs.

[0117] A UE participating in a sidelink group communication with one or more other UEs sends sidelink transmissions to and / or receives sidelink transmissions from one or more other UEs in the group. In order to distinguish transmissions intended for members of the sidelink communication group from non-group transmissions, the sidelink group transmission may include a group-specific destination identifier. For example, the group identifier may be a Layer 2 (i.e., access layer) group identifier. The purpose of the group identifier is that the UE may be a member of multiple groups and therefore needs to know which group a particular message is associated with. When a UE sends a message with the sidelink communication group as the destination, it is expected / assumed that the message will be received by all other members of the group.

[0118] In one aspect, each member of the group maintains a first transmit counter of the number of packets sent by the member UE as part of the sidelink group communication (note that a group message may include one or more packets, depending on the type and size of the message). Each UE also maintains a set of receive counters, one for each other group member UE, to track the number of packets received from each member UE. A UE-specific source identifier (e.g., a Layer 2 identifier) ​​may be used to identify group members, and each transmitting group member UE may include the identifier in the sidelink messages it sends. In addition, as described above, each transmission (more specifically, each packet of each sidelink message) may include a group-specific destination identifier (e.g., a Layer 2 identifier) ​​indicating that the transmission is intended for the sidelink communication group.

[0119] Each UE may periodically send a message to the leader UE of the sidelink communication group or the base station serving the sidelink communication group (e.g. Figure 1 The base station 102 in Figure 2A and Figure 2B The UE may report transmit counters and receive counters to the ng-eNB 224 or gNB 222 in the UE. Based on these counters, the UE may receive commands from the group leader or base station to adjust its sidelink transmissions, as further described below. The commands may include transmit power control commands, triggers to perform beam improvement procedures, and / or triggers to perform beam failure recovery procedures.

[0120] In one aspect, the configuration indicating whether or when to report a counter to a group leader or base station may be a configuration that is sent periodically or based on certain events. If periodic reporting is configured, the configuration may indicate the period of the report, the time offset of the report, and / or the time window within which the UE may attempt to send the counter. For example, the time window may be represented as: (time_offset, time_offset+time_wndow)+k*time_period. If event-based reporting is configured, the member UEs may be configured with counter thresholds indicating when to report the send counter and the receive counter. For example, each member UE may be configured to report the counter when the value of the counter exceeds 10 counts. The UE may report the counters separately when their counts reach the threshold, or may report all counters together when at least one counter reaches the threshold. In addition, the count thresholds may be different for different counters (e.g., a send counter may be associated with one threshold, while a receive counter may be associated with a different count threshold).

[0121] Based on the counters received from the different group member UEs, the group leader UE or base station can determine whether the link between any two UEs in the sidelink communication group is no longer "closed" (i.e., the transmission from at least one UE in a pair of UEs is not received by the other UE in the pair). In this case, the group leader or base station can send a command to one or both of the UEs to "close" (i.e., re-establish) the link between them.

[0122] For example, if a particular side link between a first group member UE and a second group member UE is suddenly blocked, then at the next counter reporting period, the first UE will report that it has sent "N" packets to the second UE, and the second UE will report that it has received less than "N" packets from the first UE. The group leader or base station may then send, for example, a power control command to the first UE (and the second UE) to shut down the side link between them, or send a command to trigger a beam failure recovery (BFR) procedure to establish a different beam pair between the UEs that may not be blocked.

[0123] The command that the group leader or base station can send to a pair of UEs includes a transmit power control command, a command to reconfigure the QoS of the side link, an instruction to perform a beam improvement procedure, an instruction to perform a beam failure recovery procedure, or any combination thereof. In the case where the command is to reconfigure the QoS of the side link, the UE can use a lower modulation and coding scheme (MCS) for transmission over the side link. In one aspect, this can be done using an upper limit on the MCS that the UE can use.

[0124] In one aspect, transmissions to / from the group leader UE or base station may always be associated with an ACK / NACK, regardless of whether the sidelink group communication uses NACK-only feedback or no HARQ feedback at all. In this case, any command from the group leader and the reporting of the counter to the group leader should be acknowledged (using ACK or NACK). That is, the member UEs should acknowledge the commands from the group leader, and the group leader should acknowledge the counter reports from the member UEs.

[0125] Figure 6 An example method 600 of wireless communication in accordance with aspects of the present disclosure is shown. In one aspect, the method 600 may be performed by a UE (eg, any UE described herein) participating in a sidelink communication group.

[0126] At 610, the first UE increments a transmit counter for each packet transmitted by the first UE as part of a group communication among the side link communication group. In one aspect, operation 610 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, memory component 440, and / or side link manager 442, any or all of which may be considered means for performing the operation.

[0127] At 620, the first UE increments a receive counter for each packet received by the first UE from a second UE participating in the side link communication group as part of a group communication in the side link communication group. In one aspect, operation 620 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, memory component 440, and / or side link manager 442, any or all of which may be considered means for performing the operation.

[0128] At 630, the first UE sends a transmit counter and a receive counter to a network node (e.g., a group leader, such as any of the UEs described herein, or a base station serving one or more UEs of the sidelink communication group) based on the configuration received from the network node. In one aspect, operation 630 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, memory component 440, and / or sidelink manager 442, any or all of which may be considered as means for performing the operation.

[0129] Figure 7 An example method 700 for wireless communication according to aspects of the present disclosure is shown. In one aspect, the method 700 may be performed by a network node associated with a sidelink communication group (e.g., a group leader, such as any UE described herein, or a base station serving one or more UEs of the sidelink communication group).

[0130] At 710, the network node receives a transmit counter from a first UE (e.g., any UE described herein) participating in a sidelink communication group, the transmit counter indicating the number of packets transmitted by the first UE as part of a group communication in the sidelink communication group. In one aspect, where the network node is a group leader UE, operation 710 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, a memory component 440, and / or a sidelink manager 442, any or all of which may be considered as a component for performing the operation. Similarly, where the network node is a base station, operation 710 may be performed by at least one WWAN transceiver 450, at least one short-range wireless transceiver 460, at least one processor 484, a memory component 486, and / or a sidelink manager 488, any or all of which may be considered as a component for performing the operation.

[0131] At 720, the network node receives a receive counter from a second UE (e.g., any UE described herein) participating in the sidelink communication group, the receive counter indicating the number of packets received by the second UE from the first UE as part of a group communication in the sidelink communication group. In one aspect, where the network node is a group leader UE, operation 720 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, a memory component 440, and / or a sidelink manager 442, any or all of which may be considered as a component for performing the operation. Similarly, where the network node is a base station, operation 720 may be performed by at least one WWAN transceiver 450, at least one short-range wireless transceiver 460, at least one processor 484, a memory component 486, and / or a sidelink manager 488, any or all of which may be considered as a component for performing the operation.

[0132] At 730, the network node determines whether there is a mismatch between the transmit counter and the receive counter based on the transmit counter and the receive counter. In one aspect, in the case where the network node is a group leader UE, operation 730 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, memory component 440, and / or side link manager 442, any one or all of which may be considered as a means for performing the operation. Similarly, in the case where the network node is a base station, operation 730 may be performed by at least one WWAN transceiver 450, at least one short-range wireless transceiver 460, at least one processor 484, memory component 486, and / or side link manager 488, any one or all of which may be considered as a means for performing the operation.

[0133] At 740, the network node sends a command to at least the first UE to reestablish a side link with the second UE based on the mismatch between the transmit counter and the receive counter. In one aspect, where the network node is a group leader UE, operation 740 may be performed by at least one WWAN transceiver 410, at least one short-range wireless transceiver 420, at least one processor 432, a memory component 440, and / or a side link manager 442, any one or all of which may be considered as a means for performing the operation. Similarly, where the network node is a base station, operation 740 may be performed by at least one WWAN transceiver 450, at least one short-range wireless transceiver 460, at least one processor 484, a memory component 486, and / or a side link manager 488, any one or all of which may be considered as a means for performing the operation.

[0134] As will be appreciated, a technical advantage of methods 600 and 700 is determining whether a link between any two UEs in a sidelink communication group is no longer "closed."

[0135] It can be seen in the above detailed description that different features are combined together in the examples. This disclosure should not be understood as an intention that the example clauses have more features than those explicitly mentioned in each clause. On the contrary, various aspects of the present disclosure may include less than all the features of the disclosed individual example clauses. Therefore, the following clauses should be deemed to be included in the specification, where each clause itself can be used as a separate example. Although each dependent clause can be referenced in a clause to a specific combination with one of the other clauses, the (one or more) aspects of the dependent clause are not limited to the specific combination. It should be understood that other example clauses may also include a combination of (one or more) aspects of the dependent clauses with the subject matter of any other dependent clause or independent clause, or any combination of features with other dependent and independent clauses. Various aspects disclosed herein explicitly include these combinations, unless it is clearly expressed or can be easily inferred that a specific combination is not intended (for example, contradictory aspects, such as defining an element as both an insulator and a conductor at the same time). In addition, even if the clause is not directly dependent on the independent clause, the various aspects of the clause may be included in any other independent clause.

[0136] Implementation examples are described in the following numbered clauses:

[0137] Clause 1. A method for wireless communication performed by a first user equipment (UE) participating in a sidelink communication group, comprising: incrementing a send counter for each packet sent by the first UE as part of a group communication in the sidelink communication group; incrementing a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication in the sidelink communication group; and sending a send counter and a receive counter to a network node based on a configuration received from the network node.

[0138] Clause 2. The method of clause 1, wherein the first UE increments a reception counter maintained for the UE in response to receiving a packet from each member of the sidelink communication group.

[0139] Clause 3. A method according to any one of clauses 1 to 2, wherein the configuration specifies a period for sending a send counter and a receive counter, a time offset for sending a send counter and a receive counter, and / or a time window within which to send a send counter and a receive counter.

[0140] Clause 4. The method of any one of clauses 1 to 3, wherein the configuration specifies at least one counting threshold for the send counter and the receive counter.

[0141] Clause 5. The method of clause 4, wherein the at least one count threshold is a single count threshold applicable to both the transmit counter and the receive counter.

[0142] Clause 6. The method of any of clauses 4 to 5, wherein the at least one counting threshold comprises separate counting thresholds for a transmit counter and a receive counter.

[0143] Clause 7. A method as described in any of clauses 1 to 6, further comprising: receiving a command from the network node to re-establish the side link with the second UE.

[0144] Clause 8. A method according to clause 7, wherein the command includes: a send power control command, a command for reconfiguring the quality of service (QoS) of the side link, a command for performing a beam improvement procedure with the second UE, a command for performing a beam failure procedure with the second UE, or any combination thereof.

[0145] Clause 9. The method of clause 8, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE may use for transmission over the sidelink.

[0146] Clause 10. The method of any of clauses 7 to 9, further comprising: sending an acknowledgement to the network node in response to receiving the command.

[0147] Clause 11. A method as described in any of clauses 7 to 10, wherein the first UE receives the command based on the transmission counter and the reception counter indicating a sidelink failure between the first UE and the second UE.

[0148] Clause 12. The method of any of clauses 1 to 11, further comprising: receiving a confirmation of the sending of the send counter and the receive counter from the network node.

[0149] Clause 13. A method as described in any of clauses 1 to 12, wherein the network node comprises a base station serving the first UE and the second UE.

[0150] Clause 14. A method as described in any of clauses 1 to 12, wherein the network node comprises a group leader UE of the sidelink communication group.

[0151] Clause 15. A method for wireless communication performed by a network node associated with a sidelink communication group, comprising: receiving a send counter from a first UE participating in the sidelink communication group, the send counter indicating the number of packets sent by the first UE as part of group communication within the sidelink communication group; receiving a receive counter from a second UE participating in the sidelink communication group, the receive counter indicating the number of packets received by the second UE from the first UE as part of group communication within the sidelink communication group; determining whether there is a mismatch between the send counter and the receive counter based on the send counter and the receive counter; and sending a command to at least the first UE for re-establishing a sidelink with the second UE based on the mismatch between the send counter and the receive counter.

[0152] Clause 16. The method of clause 15, wherein: the network node receives a transmit counter from each member of the sidelink communication group, and the network node receives a receive counter from each member of the sidelink communication group.

[0153] Clause 17. A method as described in any of clauses 15 to 16, further comprising: sending a configuration for a transmit counter to the first UE; and sending a configuration for a receive counter to the second UE.

[0154] Clause 18. A method according to Clause 17, wherein: the configuration for the send counter specifies the period of the send counter, the time offset of the send counter and / or the time window within which the send counter is sent, and the configuration for the receive counter specifies the period of the send receive counter, the time offset of the send receive counter and / or the time window within which the receive counter is sent.

[0155] Clause 19. A method according to any of clauses 17 to 18, wherein: the configuration for the transmit counter specifies a count threshold for the transmit counter, and the configuration for the receive counter specifies a count threshold for the receive counter.

[0156] Clause 20. The method of clause 19, wherein a count threshold for the send counter is the same as a count threshold for the receive counter.

[0157] Clause 21. A method according to any one of clauses 15 to 20, wherein the command comprises: a send power control command, a command for reconfiguring the quality of service (QoS) of a side link between a first UE and a second UE, a command for performing a beam improvement procedure with the second UE, a command for performing a beam failure procedure with the second UE, or any combination thereof.

[0158] Clause 22. The method of clause 21, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE may use for transmission over the sidelink.

[0159] Clause 23. A method as described in any of clauses 15 to 22, further comprising: receiving an acknowledgement from at least the first UE in response to the sending of the command.

[0160] Clause 24. A method as described in any of clauses 15 to 23, further comprising: sending an acknowledgement of receipt of the transmit counter to the first UE; and sending an acknowledgement of receipt of the receive counter to the second UE.

[0161] Clause 25. The method according to any one of clauses 15 to 24 further includes: receiving a second sending counter from the second UE, the second sending counter indicating the number of packets sent by the second UE as part of the group communication within the side link communication group; and receiving a second receiving counter from the first UE, the second receiving counter indicating the number of packets received by the first UE from the second UE as part of the group communication within the side link communication group.

[0162] Clause 26. The method of clause 25, wherein the determining is further based on a mismatch between the second transmit counter and the second receive counter.

[0163] Clause 27. A method as described in any of clauses 15 to 26, wherein the network node comprises a base station serving the first UE and the second UE.

[0164] Clause 28. A method as described in any of clauses 15 to 26, wherein the network node comprises a group leader UE of the sidelink communication group.

[0165] Clause 29. A first user equipment (UE) comprising: a memory; a communication interface; and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to: increment a send counter for each packet sent by the first UE as part of a group communication within a sidelink communication group; increment a receive counter for each packet received by the first UE from a second UE participating in the sidelink communication group as part of a group communication within the sidelink communication group; and cause the communication interface to send a send counter and a receive counter to a network node based on a configuration received from the network node.

[0166] Clause 30. The first UE of clause 29, wherein the first UE increments a receive counter maintained for each member of the sidelink communication group in response to receiving a packet from the UE.

[0167] Clause 31. A first UE according to any of clauses 29 to 30, wherein the configuration specifies a period for sending the send counter and the receive counter, a time offset for sending the send counter and the receive counter, and / or a time window within which to send the send counter and the receive counter.

[0168] Clause 32. The first UE of any of clauses 29 to 31, wherein the configuration specifies at least one counting threshold for the transmit counter and the receive counter.

[0169] Clause 33. The first UE of clause 32, wherein the at least one counting threshold is a single counting threshold applicable to both the transmit counter and the receive counter.

[0170] Clause 34. The first UE as described in any of clauses 32 to 33, wherein the at least one count comprises separate count thresholds for the transmit counter and the receive counter.

[0171] Clause 35. The first UE of any of clauses 29 to 34, wherein the at least one processor is further configured to: receive a command from the network node via the communication interface to re-establish a side link with the second UE.

[0172] Clause 36. A first UE according to clause 35, wherein the command comprises: a transmit power control command, a command for reconfiguring the quality of service (QoS) of a side link, a command for performing a beam improvement procedure with a second UE, a command for performing a beam failure procedure with a second UE, or any combination thereof.

[0173] Clause 37. The first UE of clause 36, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE may use for transmission over the sidelink.

[0174] Clause 38. The first UE of any of clauses 35 to 37, wherein the at least one processor is further configured to cause the communication interface to send an acknowledgement to the network node in response to receiving the command.

[0175] Clause 39. A first UE as described in any of clauses 35 to 38, wherein the first UE receives the command based on the transmit counter and the receive counter indicating a sidelink failure between the first UE and the second UE.

[0176] Clause 40. The first UE of any of clauses 29 to 39, wherein the at least one processor is further configured to: receive, via the communication interface, from the network node an acknowledgement of the sending of the send counter and the receive counter.

[0177] Clause 41. The first UE as set forth in any of clauses 29 to 40, wherein the network node comprises a base station serving the first UE and the second UE.

[0178] Clause 42. The first UE of any of clauses 29 to 40, wherein the network node comprises a leader UE of the sidelink communication group.

[0179] Clause 43. A network node, comprising: a memory; a communication interface; and at least one processor communicatively coupled to the memory and the communication interface, the at least one processor being configured to: receive a send counter from a first UE participating in a side link communication group via the communication interface, the send counter indicating the number of packets sent by the first UE as part of a group communication in the side link communication group; receive a receive counter from a second UE participating in the side link communication group via the communication interface, the receive counter indicating the number of packets received by the second UE from the first UE as part of a group communication in the side link communication group; determine whether there is a mismatch between the send counter and the receive counter based on the send counter and the receive counter; and based on the mismatch between the send counter and the receive counter, cause the communication interface to send a command to at least the first UE for reestablishing a side link with the second UE.

[0180] Clause 44. A network node according to clause 43, wherein: the network node receives a transmit counter from each member of the side link communication group, and the network node receives a receive counter from each member of the side link communication group.

[0181] Clause 45. A network node as described in any of clauses 43 to 44, wherein the at least one processor is further configured to: cause the communication interface to send a configuration for a transmit counter to the first UE; and cause the communication interface to send a configuration for a receive counter to the second UE.

[0182] Clause 46. A network node according to clause 45, wherein: the configuration for the send counter specifies a period for sending the send counter, a time offset for sending the send counter and / or a time window within which the send counter is sent, and the configuration for the receive counter specifies a period for sending the receive counter, a time offset for sending the receive counter and / or a time window within which the receive counter is sent.

[0183] Clause 47. A network node as set forth in any of clauses 45 to 46, wherein the configuration for the transmit counter specifies a count threshold for the transmit counter, and the configuration for the receive counter specifies a count threshold for the receive counter.

[0184] Clause 48. The network node of Clause 47, wherein the count threshold for the transmit counter is the same as the count threshold for the receive counter.

[0185] Clause 49. A network node according to any one of clauses 43 to 48, wherein the command comprises: a send power control command, a command for reconfiguring the quality of service (QoS) of a side link between the first UE and the second UE, a command for performing a beam improvement procedure with the second UE, a command for performing a beam failure procedure with the second UE, or any combination thereof.

[0186] Clause 50. The network node of clause 49, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE may use for transmission over the sidelink.

[0187] Clause 51. The network node of any of clauses 43 to 50, wherein the at least one processor is further configured to: receive, via the communications interface, from at least the first UE an acknowledgement in response to the sending of the command.

[0188] Clause 52. A network node according to any of clauses 43 to 51, wherein at least one processor is further configured to: cause the communication interface to send a confirmation of receiving the transmit counter to the first UE; and cause the communication interface to send a confirmation of receiving the receive counter to the second UE.

[0189] Clause 53. A network node according to any one of clauses 43 to 52, wherein at least one processor is further configured to: receive a second sending counter from a second UE via a communication interface, the second sending counter indicating the number of packets sent by the second UE as part of a group communication within a side link communication group; and receive a second receiving counter from a first UE via a communication interface, the second receiving counter indicating the number of packets received by the first UE from the second UE as part of a group communication within the side link communication group.

[0190] Clause 54. The network node of clause 53, wherein the determination is further based on a mismatch between the second transmit counter and the second receive counter.

[0191] Clause 55. A network node as described in any of clauses 43 to 54, wherein the network node comprises a base station serving the first UE and the second UE.

[0192] Clause 56. A network node as described in any of clauses 43 to 54, wherein the network node comprises a group leader UE of a sidelink communication group.

[0193] Clause 57. An apparatus comprising means for performing the method of any one of clauses 1 to 28.

[0194] Clause 58. A non-transitory computer-readable medium storing computer-executable instructions, the computer-executable instructions comprising at least one instruction for causing a computer or a processor to perform the method according to any one of clauses 1 to 28.

[0195] Those skilled in the art will appreciate that any of a variety of different technologies and techniques may be used to represent information and signals. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above specification may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0196] In addition, it will be appreciated by those skilled in the art that various illustrative logic blocks, modules, circuits and algorithmic steps described in conjunction with various aspects disclosed herein can be implemented as electronic hardware, computer software or a combination of the two. In order to clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits and steps have been described above generally according to their functions. Such functions are implemented as hardware or software depending on specific applications and according to the design constraints imposed by the overall system. The technician can implement the functions in different ways for each specific application, but such implementation method decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0197] The various illustrative logical blocks, modules, and circuits described in conjunction with the various aspects disclosed herein may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0198] The methods, sequences and / or algorithms described in conjunction with the various aspects disclosed herein may be directly implemented in hardware, software modules executed by a processor, or 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 example storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Alternatively, the storage medium may be integrated with 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 in a user terminal as discrete components.

[0199] In one or more example aspects, the described functions can be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions can be stored on or sent by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, which include any media that are conducive to transferring a computer program from one place to another. Storage media can be any available media that can be accessed by a computer. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM, or other optical disk storage devices, disk storage devices, or other magnetic storage devices, or may be used to carry or store the required program code in the form of an instruction or data structure and any other medium that can be accessed by a computer. In addition, any connection is appropriately referred to as a computer-readable medium. For example, if the software is sent from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (such as infrared, radio, and microwave), coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (such as infrared, radio, and microwave) may be included in the definition of the medium. Disks and optical disks as used herein include compact disks (CDs), laser disks, optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks, where disks typically reproduce data magnetically, while optical disks reproduce data optically using lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0200] Although the foregoing disclosure shows the exemplary aspects of the present disclosure, it should be noted that various changes and modifications may be made herein without departing from the scope of the present disclosure as defined by the appended claims. The functions, steps and / or actions of the method claims according to the various aspects of the present disclosure described herein do not need to be performed in any particular order. In addition, although the elements of the present disclosure may be described or claimed in the singular, the plural form may also be envisioned unless a limitation to the singular form is explicitly stated.

Claims

1. A method for wireless communication performed by a first user equipment (UE) participating in a sidelink communication group, comprising: sending one or more packets as part of a group communication among the sidelink communication group; incrementing a transmit counter for each packet transmitted by the first UE as part of the group communication among the sidelink communication group; receiving one or more packets from a second UE participating in the sidelink communication group as part of a group communication among the sidelink communication group; incrementing a receive counter for each packet received by the first UE as part of the group communication among the sidelink communication group from the second UE participating in the sidelink communication group; sending the send counter and the receive counter to the network node based on a configuration received from the network node; as well as A command is received from the network node to re-establish a sidelink with the second UE.

2. The method of claim 1, wherein the first UE increments a reception counter maintained for the UE in response to receiving a packet from each member of the sidelink communication group.

3. The method according to claim 1, wherein the configuration specifies a period for sending the send counter and the receive counter, a time offset for sending the send counter and the receive counter, and / or a time window within which the send counter and the receive counter are sent. The method of claim 1 , wherein the configuration specifies at least one counting threshold for the send counter and the receive counter. 5 . The method of claim 4 , wherein the at least one count threshold is a single count threshold applicable to both the send counter and the receive counter.

6. The method of claim 4, wherein the at least one count threshold comprises separate count thresholds for the transmit counter and the receive counter.

7. The method of claim 1, wherein the command comprises: Send power control commands, a command for reconfiguring the quality of service (QoS) of the side link, a command for performing a beam improving procedure with the second UE, a command for performing a beam failure procedure with the second UE, or any combination thereof.

8. The method of claim 7, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE can use for transmission over the sidelink.

9. The method according to claim 1, further comprising: An acknowledgement is sent to the network node in response to receiving the command.

10. The method of claim 1, wherein the first UE receives the command based on the transmit counter and the receive counter indicating a sidelink failure between the first UE and the second UE.

11. The method according to claim 1, further comprising: An acknowledgement of the transmission of the transmission counter and the reception counter is received from the network node.

12. The method of claim 1, wherein the network node comprises a base station serving the first UE and the second UE.

13. The method according to claim 1, wherein the network node comprises a group leader UE of the sidelink communication group.

14. A method for wireless communication performed by a network node associated with a sidelink communication group, comprising: receiving, from a first UE participating in the sidelink communication group, a transmit counter indicating a number of packets transmitted by the first UE as part of a group communication among the sidelink communication group; receiving, from a second UE participating in the sidelink communication group, a receive counter indicating a number of packets received by the second UE from the first UE as part of a group communication among the sidelink communication group; determining whether there is a mismatch between the transmit counter and the receive counter based on the transmit counter and the receive counter; as well as Based on the mismatch between the transmit counter and the receive counter, a command is sent to at least the first UE to reestablish a side link with the second UE.

15. The method according to claim 14, wherein: The network node receives a transmit counter from each member of the sidelink communication group, and The network node receives a reception counter from each member of the sidelink communication group.

16. The method according to claim 14, further comprising: Sending a configuration for the sending counter to the first UE; as well as Sending a configuration for the reception counter to the second UE.

17. The method of claim 16, wherein: The configuration for the send counter specifies a period for sending the send counter, a time offset for sending the send counter, and / or a time window within which the send counter is sent, and The configuration for the receive counter specifies a period for sending the receive counter, a time offset for sending the receive counter, and / or a time window within which the receive counter is sent.

18. The method of claim 16, wherein: The configuration for the transmit counter specifies a count threshold for the transmit counter, and The configuration for the receive counter specifies a count threshold for the receive counter.

19. The method of claim 18, wherein a count threshold for the transmit counter is the same as a count threshold for the receive counter.

20. The method of claim 14, wherein the command comprises: Send power control commands, a command for reconfiguring a quality of service (QoS) of a side link between the first UE and the second UE, a command for performing a beam improving procedure with the second UE, a command for performing a beam failure procedure with the second UE, or any combination thereof.

21. The method of claim 20, wherein the command to reconfigure the QoS of the sidelink comprises an upper limit on a modulation and coding scheme (MCS) that the first UE can use for transmission over the sidelink.

22. The method of claim 14, further comprising: An acknowledgement is received from at least the first UE in response to the sending of the command.

23. The method of claim 14, further comprising: sending, to the first UE, an acknowledgement of receiving the send counter; as well as An acknowledgement of receipt of the reception counter is sent to the second UE.

24. The method of claim 14, further comprising: receiving, from the second UE, a second transmit counter indicating a number of packets transmitted by the second UE as part of a group communication among the sidelink communication group; as well as A second reception counter is received from the first UE, the second reception counter indicating a number of packets received by the first UE from the second UE as part of a group communication among the sidelink communication group.

25. The method of claim 24, wherein the determining is further based on a mismatch between the second transmit counter and the second receive counter.

26. The method of claim 14, wherein the network node comprises a base station serving the first UE and the second UE.

27. The method of claim 14, wherein the network node comprises a leader UE of the sidelink communication group.

28. A first user equipment (UE), comprising: Memory; Communication interface; as well as at least one processor communicatively coupled to the memory and the communication interface, the at least one processor configured to: sending one or more packets as part of a group communication within a sidelink communication group; incrementing a transmit counter for each packet transmitted by the first UE as part of the group communication in a sidelink communication group; receiving one or more packets from a second UE participating in the sidelink communication group as part of a group communication among the sidelink communication group; incrementing a receive counter for each packet received by the first UE as part of the group communication among the sidelink communication group from the second UE participating in the sidelink communication group; causing the communication interface to send the send counter and the receive counter to the network node based on a configuration received from the network node; as well as A command is received from the network node to re-establish a sidelink with the second UE.

29. A network node, comprising: Memory; Communication interface; as well as at least one processor communicatively coupled to the memory and the communication interface, the at least one processor configured to: receiving, via the communication interface, a transmit counter from a first UE participating in a sidelink communication group, the transmit counter indicating a number of packets transmitted by the first UE as part of a group communication among the sidelink communication group; receiving, via the communication interface, a receive counter from a second UE participating in the sidelink communication group, the receive counter indicating a number of packets received by the second UE from the first UE as part of a group communication among the sidelink communication group; determining whether there is a mismatch between the transmit counter and the receive counter based on the transmit counter and the receive counter; as well as Based on the mismatch between the sending counter and the receiving counter, the communication interface is caused to send a command to at least the first UE for re-establishing a side link with the second UE.

30. A first user equipment (UE), comprising: means for transmitting one or more packets as part of a group communication among a sidelink communication group; means for incrementing a transmit counter for each packet transmitted by the first UE as part of the group communication among the sidelink communication group; means for receiving one or more packets from a second UE participating in the sidelink communication group as part of a group communication among the sidelink communication group; means for incrementing a receive counter for each packet received by the first UE from the second UE participating in the sidelink communication group as part of the group communication among the sidelink communication group; means for sending the send counter and the receive counter to the network node based on a configuration received from the network node; as well as Means for receiving a command from the network node to re-establish a sidelink with the second UE.

31. A non-transitory computer readable medium having stored thereon one or more instructions for implementing the method of any one of claims 1-13 when executed by a computer.

32. A network node, comprising: means for receiving, from a first UE participating in a sidelink communication group, a transmit counter indicating a number of packets transmitted by the first UE as part of a group communication among the sidelink communication group; means for receiving, from a second UE participating in the sidelink communication group, a reception counter indicating a number of packets received by the second UE from the first UE as part of a group communication among the sidelink communication group; means for determining whether there is a mismatch between the sending counter and the receiving counter based on the sending counter and the receiving counter; as well as Means for sending, to at least the first UE, a command to reestablish a sidelink with the second UE based on the mismatch between the transmit counter and the receive counter.

33. A non-transitory computer readable medium having stored thereon one or more instructions for implementing the method of any one of claims 14-27 when executed by a computer.

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