Methods and apparatus for sidelink resource collision handling and resource allocation by user equipment coordination

Abstract

A user equipment (UE) can detect a collision or interference problem of a second UE and transmit information to a base station about the detected collision. The second UE can not be able to sense the channel on its own and thus can inadvertently use a resource that has been reserved or is being used by another UE. The information about the detected collision can include a layer 1 identifier (L1 ID) and / or a layer 2 identifier (L2 ID) corresponding to the UE and / or the second UE and additional information corresponding to the resource collision. The information can be able to be used by the base station to determine that the base station has previously communicated with the second UE and can trigger resource reselection of the second UE. The UE can receive a sidelink communication from the second UE on one or more reselected sidelink transmission resources.

Description

TECHNICAL FIELD

[0001] The present application relates to wireless devices, and more specifically to apparatus, systems, and methods for detecting and reporting, on behalf of user equipment, sidelink collision / interference problems via a base station and coordinating UEs in order to provide improved sidelink resource allocation.

[0002] DESCRIPTION OF RELATED ART

[0003] The use of wireless communication systems is increasing rapidly. One recent development in cellular communications is known as sidelink communication, in which two user equipment (UE) devices communicate with each other without an intervening base station. One proposed use of sidelink wireless communication is in vehicular applications, particularly in V2X (vehicle-to-anything) systems. V2X systems allow for communication between vehicles (e.g., through communication devices housed in or otherwise carried by vehicles), pedestrian UEs (including UEs carried by other people such as cyclists, etc.), and other wireless communication devices for various purposes such as to coordinate traffic activity, facilitate autonomous driving, and perform collision avoidance.

[0004] Increased communication requirements of certain V2X systems can strain the power and resource capabilities of portable, battery-powered UE devices. Moreover, some UEs can lack sidelink reception capabilities for communicating with other UEs or can experience interference from other UEs, which can result in increased resource collisions during sidelink communication and can further present problems of reduced battery life, increased latency, and decreased communication quality. Accordingly, improvements in this area would be desirable. SUMMARY

[0005] Embodiments of apparatus, systems, and methods are presented herein for detecting and reporting, on behalf of user equipment (UE), sidelink collision / interference problems via a base station and coordinating UEs in order to minimize resource collisions and provide improved sidelink resource allocation as well as reduce latency and power consumption and enhance reliability.

[0006] Some embodiments relate to a user equipment (UE) including at least one antenna, a radio operably coupled to the at least one antenna, and a processor operably coupled to the radio. The (first) UE can be further configured to detect a sidelink collision / interference problem of another (second) UE and transmit information about the detected collision to a base station. The second UE can be a fully capable UE (capable of both sidelink transmission and sidelink reception) or can be a transmit-only UE. Due to various circumstances that can arise, the second UE can not be able to adequately sense the sidelink channel for available resources. In the case that the second UE is a transmit-only UE, the second UE can not be able to sense the channel on its own and, as a result, can inadvertently use resources that have been reserved or are being used by other UEs.

[0007] The information about the detected collision can include address or identifier information sufficient for the base station to identify the second UE (“culprit UE”) and additional information corresponding to the resource collision. For example, the address or identifier information can include a layer 1 identifier (L1 ID) and / or a layer 2 identifier (L2 ID) corresponding to the UE and / or the second UE. The information about the detected collision can be usable by the base station to determine that the base station has previously communicated with the second UE and can also cause the base station to trigger resource reselection of the second UE. When the second UE receives new resources as a result of its reselection, the second UE can then begin transmitting using the resources. The first UE can then receive sidelink communications from the second UE on the one or more reselected sidelink transmission resources.

[0008] In some aspects, the second UE can be a transmit-only UE and can be configured to periodically transmit sidelink communications indicating that it is a transmit-only UE. Also, in other aspects, the second UE can be further configured to function as a mode 1 UE. Also, the second UE can be configured to transmit signaling to a base station, where the signaling at least partially includes at least one layer 2 (L2) identifier (ID).

[0009] Some embodiments can relate to a user equipment (UE) device having at least one antenna for performing wireless communications, a radio, and a processing element coupled to the radio. The UE can perform at least some of the methods described herein.

[0010] Some embodiments can relate to a baseband processor having processing circuitry configured to perform at least a portion or all of the operations described above.

[0011] Some embodiments can involve a base station having a plurality of antennas, a radio operably coupled to the plurality of antennas, and a processor operably coupled to the radio, where the base station can be configured to perform at least a portion or all of the operations described above.

[0012] This Summary is intended to provide a brief overview of some of the subject matter described in this document. Accordingly, it will be appreciated that the above-described features are merely examples and should not be construed to narrow the scope or spirit of the subject matter as described herein. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following DETAILED DESCRIPTION, Figures, and Claims. BRIEF DESCRIPTION OF DRAWINGS

[0013] A better understanding of the present subject matter will be obtained through consideration of the following detailed description in conjunction with the drawings, in which:

[0014] Figure 1 An example vehicle-to-everything (V2X) communication system is shown in accordance with some embodiments;

[0015] Figure 2 A base station in communication with a user equipment (UE) device is shown in accordance with some embodiments;

[0016] Figure 3 An example block diagram of a UE in accordance with some embodiments is shown;

[0017] Figure 4 An example block diagram of a base station in accordance with some embodiments is shown;

[0018] Figure 5 An example of a vehicle-to-everything network is shown in accordance with some embodiments;

[0019] Figure 6 A transmitting-only UE operating in a V2X environment is shown in accordance with some embodiments.

[0020] Figure 7A And Figure 7B A half-duplex and hidden node resource collision problem is shown in accordance with some embodiments.

[0021] Figure 8 A flow diagram showing inter-UE coordination for resource collision avoidance and resource allocation via a base station is shown in accordance with some embodiments.

[0022] While the features described herein can be susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the disclosure to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the subject matter defined by the appended claims. DETAILED DESCRIPTION

[0023] TERMINOLOGY

[0024] Various acronyms are used throughout this disclosure. Definitions of the most prominent acronyms used throughout this disclosure can appear as follows:

[0025] • UE: User Equipment

[0026] • RF: Radio Frequency

[0027] • BS: Base Station

[0028] • GSM: Global System for Mobile Communications

[0029] • UMTS: Universal Mobile Telecommunications System

[0030] • LTE: Long Term Evolution

[0031] • NR: New Radio

[0032] • NR-U: NR Unlicensed

[0033] • TX: Transmit

[0034] • RX: Receive

[0035] • RAT: Radio Access Technology

[0036] • DCI: Downlink Control Information

[0037] • V2X: Vehicle-to-Everything

[0038] • PSCCH: Physical Sidelink Control Channel

[0039] • PSSCH: Physical Sidelink Shared Channel

[0040] • PUCCH: Physical Uplink Control Channel

[0041] • PUE: Pedestrian User Equipment

[0042] • VUE: Vehicle User Equipment

[0043] • SCI: Sidelink Control Information

[0044] TX-UE: Launches user equipment only

[0045] VRU: Vulnerable Road Users

[0046] ·SL: Side Link

[0047] L1: Layer 1

[0048] L2: Layer 2

[0049] The following is a glossary of terms used in this disclosure:

[0050] Memory media—any device of any type of nontransitory memory device or storage device. The term "memory media" is intended to include mounting media such as CD-ROMs, floppy disks, or magnetic tape devices; computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory such as flash memory, magnetic media, e.g., hard disk drives or optical storage devices; registers or other similar types of memory elements, etc. Memory media may also include other types of nontransitory memory or combinations thereof. Furthermore, memory media may reside in a first computer system executing a program, or may reside in a different second computer system connected to the first computer system via a network such as the Internet. In the latter case, the second computer system may provide program instructions to the first computer for execution. The term "memory media" may include two or more memory media that may reside in different locations on different computer systems connected via a network, for example. Memory media may store program instructions (e.g., representing a computer program) that can be executed by one or more processors.

[0051] Programmable hardware elements—including a variety of hardware devices comprising multiple programmable functional blocks connected via programmable interconnects. Examples include FPGAs (Field-Programmable Gate Arrays), PLDs (Programmable Logic Devices), FPOAs (Field-Programmable Object Arrays), and CPLDs (Complex PLDs). Programmable functional blocks can vary from fine-grained (combinatorial logic units or lookup tables) to coarse-grained (arithmetic logic units or processor cores). Programmable hardware elements may also be referred to as “configurable logic units.”

[0052] Computer system—any of all types of computing or processing systems, including personal computer systems (PCs), mainframe computer systems, workstations, networked appliances, internet-connected appliances, personal digital assistants (PDAs), television systems, grid computing systems, or other devices or combinations thereof. In general, the term "computer system" can be broadly defined to encompass any device (or combination of devices) having at least one processor that executes instructions from a memory medium.

[0053] User Equipment - As used herein, can generally refer in the context of a V2X system to devices associated with mobile actors or traffic actors in the V2X system, i.e., mobile (capable of moving) communication devices such as vehicles and pedestrian user equipment (PUE) devices, as opposed to infrastructure devices such as base stations, roadside units (RSUs), and servers.

[0054] Infrastructure Equipment - As used herein, can generally refer in the context of a V2X system to certain devices in the V2X system that are not user equipment and are not carried by a traffic actor (i.e., a pedestrian, a vehicle, or other mobile user), but rather facilitate user equipment participation in the V2X network. Infrastructure equipment includes base stations and roadside units (RSUs).

[0055] User Equipment (UE) (or “UE device”) - Any of various types of computer system devices that are mobile or portable and that perform wireless communications. Examples of UE devices include mobile phones or smart phones (e.g., iPhone TM , Android TM -based phones), portable gaming devices (e.g., Nintendo DS TM , PlayStation Portable TM , Gameboy Advance TM , iPhone TM ), laptops, wearable devices (e.g., smart watches, smart glasses), PDAs, portable Internet devices, music players, data storage devices, or other handheld devices, etc. In general, the term “UE” or “UE device” can be broadly defined to encompass any electronic, computing, and / or telecommunications device (or combination of devices) with the ability to communicate as user equipment in a wireless communication environment.

[0056] Pedestrian UE (PUE) device - User Equipment (UE) devices that can be worn or carried by a variety of people, including not only pedestrians in the strict sense who walk near a roadway, but also certain other peripheral or secondary actors or potential actors in the traffic environment. These include stationary people, people who are not on a vehicle and can not necessarily be near a roadway or traffic, people who are jogging, running, skating, etc., or people on vehicles such as bicycles, scooters, or certain motorized vehicles that can not substantially support the power capabilities of a UE. Examples of pedestrian UEs include smart phones, wearable UEs, PDAs, etc.

[0057] Base Station - The term “base station” has the full breadth of its ordinary meaning and at least includes a wireless communication station installed at a fixed location and used to communicate as part of a wireless telephone system or radio system.

[0058] processing element—refers to various elements or combinations of elements. Processing elements include, for example, circuitry such as ASICs (application specific integrated circuits), portions or circuits of individual processors, entire processors, programmable hardware devices such as FPGAs (field programmable gate arrays), and / or larger portions of systems that include multiple processors.

[0059] channel—refers to a medium used to convey information from a transmitter (TX) to a receiver (RX) in a communication link, such as wireless channels. It is noted that the characteristics of the term "channel" can differ according to different wireless protocols, and thus the term "channel" as used herein can be taken to mean the term in a manner consistent with the type of equipment to which the term is referenced. In some standards, channel widths can be variable (e.g., depending on device capability, band conditions, etc.). For example, LTE can support scalable channel bandwidths from 1.4 MHz to 20 MHz. In contrast, a WLAN channel can be 22 MHz wide, while a Bluetooth channel can be 1 MHz wide. Other protocols and standards can include different definitions of a channel. In addition, some standards can define and use multiple types of channels, such as different channels for uplink or downlink and / or different channels for different uses such as data, control information, etc.

[0060] Figure 1 -V2X communication system

[0061] Figure 1 An exemplary vehicle-to-everything (V2X) communication system is shown in accordance with some embodiments. Note that Figure 1 The system of FIG. 1 is merely one example of possible systems, and features of this disclosure can be implemented in any of various systems as desired.

[0062] A vehicle-to-everything (V2X) communication system can be characterized as a network in which vehicles, UEs, and / or other devices and network entities exchange communications in order to coordinate traffic activities, as well as other possible purposes. V2X communications include communications transmitted between vehicles (e.g., wireless devices or communication devices that form part of a vehicle or are included in or otherwise carried by a vehicle) and various other devices. V2X communications include vehicle-to-pedestrian (V2P) communications, vehicle-to-infrastructure (V2I) communications, vehicle-to-network (V2N) communications, and vehicle-to-vehicle (V2V) communications, as well as communications between vehicles and other possible network entities or devices. V2X communications can also refer to communications between other non-vehicle devices participating in a V2X network in order to share V2X-related information.

[0063] V2X communications can for example comply with 3GPP Cellular V2X (C-V2X) specifications, or one or more other or subsequent standards, whereby vehicles and other devices and network entities can communicate. V2X communications can utilize both long range (e.g., cellular) communications as well as short to medium range (e.g., non-cellular) communications. V2X communications with cellular capability can be referred to as Cellular V2X (C-V2X) communications. C-V2X systems can use various cellular radio access technologies (RATs), such as 4G LTE or 5G NR RATs. Certain LTE standards available in V2X systems can be referred to as LTE-Vehicle (LTE-V) standards.

[0064] As shown, the example V2X system includes a plurality of user equipment. As used herein in the context of a V2X system, and as defined above, the term “user equipment” can generally refer to devices associated with mobile participants or road users in the V2X system, i.e., mobile (capable of moving) communication devices such as vehicles and pedestrian user equipment (PUE) devices. User equipment in the example V2X system includes PUEs 104A and 104B and vehicles 106A and 106B.

[0065] Vehicles 106 can constitute various types of vehicles. For example, vehicle 106A can be a road vehicle or car, a public transit vehicle, or another type of vehicle. Vehicles 106 can communicate wirelessly in various ways. For example, vehicle 106A can include communication equipment that is part of the vehicle or housed in the vehicle, or can communicate through wireless communication devices that are currently contained within or otherwise carried by the vehicle, such as user equipment (UE) devices (e.g., smartphones or similar devices) carried or worn by a driver, passenger, or other person on the vehicle, among other possibilities. For simplicity, the term “vehicle” as used herein can include wireless communication equipment that represents and communicates for the vehicle. Thus, for example, when referring to vehicle 106A communicating wirelessly, it is to be understood that more particularly certain wireless communication equipment associated with and carried by vehicle 106A is performing the wireless communication.

[0066] A pedestrian UE (PUE) 104 can constitute various types of user equipment (UE) devices, i.e., portable devices capable of wireless communication such as smartphones, smartwatches, etc., and can be associated with various types of users. Thus, PUE 104 is a UE and can be referred to as a UE or UE device. Note that while UEs 104 can be referred to as PUEs (pedestrian UEs), they can not necessarily be carried by a person who is actively walking near a roadway or street. A PUE can refer to a UE participating in a V2X system that is carried by a person who is stationary, carried by a person who is walking or running, or carried by a person on a vehicle such as a bicycle, scooter, or certain motorized vehicles that can not substantially support the power capabilities of the device. Note also that not all UEs participating in a V2X system are PUEs.

[0067] The user equipment can be capable of communicating using multiple wireless communication standards. For example, in addition to at least one cellular communication protocol (e.g., GSM, UMTS, LTE, LTE-A, LTE-V, HSPA, 3GPP2 CDMA2000, 5G NR, etc.), the UE 104A can be configured to communicate using a wireless networking (e.g., Wi-Fi) and / or peer-to-peer wireless communication protocol (e.g., Bluetooth, Wi-Fi peer-to-peer, etc.). If desired, the UE 104A can also or alternatively be configured to communicate using one or more global navigation satellite systems (GNSS, e.g., GPS or GLONASS), one or more mobile television broadcasting standards (e.g., ATSC-M / H or DVB-H), and / or any other wireless communication protocol. Other combinations of wireless communication standards, including more than two wireless communication standards, are also possible.

[0068] As shown, certain user equipment can be capable of communicating directly with one another, i.e., without an intermediary infrastructure equipment such as base station 102A or RSU 110A. As shown, vehicle 106A can directly communicate V2X-related communications with vehicle 106B. Similarly, vehicle 106B can directly communicate V2X-related communications with PUE 104B. In the case of some LTE and / or 5G NR implementations, such peer-to-peer communications can utilize a “sidelink” interface such as a PC5 interface. In some implementations, the PC5 interface supports direct cellular communications between user equipment (e.g., between vehicles 106), while the Uu interface supports cellular communications with infrastructure equipment such as a base station. The PC5 / Uu interface is used merely as an example, and as used herein PC5 can denote various other possible wireless communication technologies that allow for direct sidelink communications between user equipment, while Uu in turn can denote cellular communications between user equipment and infrastructure equipment such as a base station. Some user equipment in the V2X system (e.g., PUE 104A) can not be capable of performing sidelink communications, e.g., because they lack certain hardware necessary to perform such communications.

[0069] As shown, the example V2X system includes a number of infrastructure equipment in addition to the user equipment described above. As used herein, “infrastructure equipment” in the context of a V2X system refers to certain equipment in the V2X system that is not a user equipment, and is not carried by a traffic participant (i.e., a pedestrian, vehicle, or other mobile user), but rather facilitates user equipment participation in the V2X network. Infrastructure equipment in the example V2X system includes base station 102A and roadside unit (RSU) 110A.

[0070] A base station (BS) 102A can be a base transceiver station (BTS) or cell site (“cell site station”), and can include hardware capable of

[0071] A base station’s area of communication (or coverage area) can be referred to as a “cell” or “coverage area.” Base station 102A and user equipment such as PUE 104A can be configured to communicate over a transmission medium using any of a variety of radio access technologies (RATs), also referred to as wireless communication technologies or telecommunication standards, such as GSM, UMTS, LTE, LTE-Advanced (LTE-A), LTE-Vehicle (LTE-V), HSPA, 3GPP2 CDMA2000, 5G NR, etc. Note that if base station 102A is implemented in the context of LTE, it can alternatively be referred to as an “eNodeB” or “eNB,” while if base station 102A is implemented in the context of 5G NR, it can alternatively be referred to as a “gNodeB” or “gNB.”

[0072] As shown, base station 102A can also be equipped to communicate with the network 100 (e.g., a V2X network, among various possibilities, as well as a core network of a cellular service provider, a telecommunications network such as the Public Switched Telephone Network (PSTN), and / or the Internet). Thus, base station 102A can facilitate communication between and / or among user equipment and the network 100. Cellular base station 102A can provide user equipment such as UE 104A with various communication capabilities such as voice, SMS, and / or data services. In particular, base station 102A can provide connected user equipment, such as UEs 104A and 106A, with access to a V2X network.

[0073] Thus, while base station 102A can act as a “serving cell” for user equipment 104A and 106A, as Figure 1 shown, user equipment 104B and 106B can also be capable of communicating with base station 102A. The user equipment shown, i.e., user equipment 104A, 104B, 106A, and 106B can also be capable of receiving signals from one or more other cells (which can be provided by base stations 102B-N and / or any other base stations), which can be referred to as “neighboring cells,” that can be within their range of communication. Such cells can also facilitate communication between and / or among user equipment and the network 100. Such cells can include “macro” cells, “micro” cells, “pico” cells, and / or any of various other granularities of service area sizes. For example, base stations 102A-B, shown in the middle, can be macro cells, while base station 102N can be a micro cell. Of course, other configurations are possible. Figure 1

[0074] Roadside Unit (RSU) 110A constitutes another infrastructure equipment that can be used to provide certain user equipment with access to a V2X network. RSU 110A can be one of various types of devices, such as a base station, e.g., a Base Transceiver Station (BTS) or a cell site (“cellular base station”), or another type of device that includes hardware capable of wirelessly communicating with user equipment and facilitating their participation in a V2X network.

[0075] RSU 110A can be configured to communicate using one or more wireless networking communication protocols (e.g., Wi-Fi), cellular communication protocols (e.g., LTE, LTE-V, 5G NR, etc.), and / or other wireless communication protocols. In some embodiments, RSU 110A can be capable of communicating with devices using “sidelink” techniques such as PC5.

[0076] ​The RSU 110A can communicate directly with user equipment such as the vehicles 106A and 106B as shown. The RSU 110A can also communicate with the base station 102A. In some cases, the RSU 110A can provide access to the base station 102A for certain user equipment (e.g., the vehicle 106B). While the RSU 110A is shown as communicating with vehicles 106, it can also (or otherwise) be capable of communicating with PUEs 104. Similarly, the RSU 110A can not necessarily forward user equipment communications to the base station 102A. In some embodiments, the RSU 110A can constitute a base station itself, and / or can forward communications to a server 120.

[0077] As shown, the server 120 constitutes a network entity of the V2X system, and can be referred to as a cloud server. The base station 102A and / or the RSU 110A can relay certain V2X-related communications between the user equipment 104 and 106 and the server 120. The server 120 can be used to process certain information collected from multiple user equipment, and can manage V2X communications to user equipment in order to coordinate traffic activities. In various other embodiments of the V2X system, various functions of the cloud server 120 can be performed by infrastructure equipment such as the base station 102A or the RSU 110A, by one or more user equipment, and / or not at all.

[0078] Figure 2 - Communications between UE and base station

[0079] Figure 2 A user equipment (UE) device 104 (e.g., one of the PUEs 104A or 104B in FIG. 1) is shown in communication with a base station 102 (e.g., the base station 102A in FIG. 1) in accordance with some embodiments. The UE 104 can be a device with cellular communication capability such as a mobile phone, a handheld device, a computer or tablet computer, or virtually any type of portable wireless device. Figure 1 Figure 1 The UE 104 can include a processor configured to execute program instructions stored in memory. The UE 104 can perform any of the method embodiments described herein by executing such stored instructions. Alternatively, or in addition, the UE 104 can include programmable hardware elements, such as an FPGA (field programmable gate array) configured to perform any of the method embodiments described herein, or any portion of a method embodiment described herein.

[0080] The UE 104 can include a processor configured to execute program instructions stored in memory. The UE 104 can perform any of the method embodiments described herein by executing such stored instructions. Alternatively, or in addition, the UE 104 can include programmable hardware elements, such as an FPGA (field programmable gate array) configured to perform any of the method embodiments described herein, or any portion of a method embodiment described herein.

[0081] ​The UE 104 can include one or more antennas to communicate using one or more wireless communication protocols or technologies. In some embodiments, the UE 104 can be configured to communicate using, for example, CDMA2000 (lxRTT / lxEV-DO / HRPD / eHRPD), LTE, and / or 5G NR using a single shared radio and / or 5G NR or LTE using a single shared radio. The shared radio can be coupled to a single antenna, or can be coupled to multiple antennas (e.g., for MIMO) for performing wireless communication. In general, a radio can comprise any combination of baseband processor(s), analog radio frequency (RF) signal processing circuitry (e.g., comprising filters, mixers, oscillators, amplifiers, etc.), or digital processing circuitry (e.g., for digital modulation as well as other digital processing). Similarly, the radio can implement one or more receive and transmit chains using the aforementioned hardware. For example, the UE 104 can share one or more portions of receive and / or transmit chains between multiple wireless communication technologies such as those discussed above.

[0082] In some embodiments, the UE 104 can include separate transmit and / or receive chains (e.g., including separate antennas and other radio components) for each wireless communication protocol configured to communicate therewith. As another possibility, the UE 104 can include one or more radios shared between multiple wireless communication protocols, as well as one or more radios used exclusively by a single wireless communication protocol. For example, the UE 104 can include a shared radio for communicating using any of LTE, 5G NR, and / or lxRTT (or LTE or GSM), as well as separate radios for communicating using each of Wi-Fi and Bluetooth. Other configurations are also possible.

[0083] Figure 3 — UE Block Diagram

[0084] Figure 3An exemplary block diagram of a UE 104 is shown, in accordance with some embodiments. As shown, the UE 104 can include a system on chip (SOC) 300, which can include portions for various purposes. For example, as shown, the SOC 300 can include a processor 302, which can execute program instructions for the UE 104, and a display circuit 304, which can perform graphics processing and provide display signals to a display 360. The one or more processors 302 can also be coupled to a memory management unit (MMU) 340 (which can be configured to receive addresses from the one or more processors 302 and translate those addresses to locations in memory, such as a memory 306, a read only memory (ROM) 350, NAND flash memory 310) and / or to other circuitry or devices, such as the display circuit 304, wireless communication circuitry 330, a connector I / F 320, and / or the display 360. The MMU 340 can be configured to perform memory protection and page table translation or set up. In some embodiments, the MMU 340 can be included as a portion of the processor 302.

[0085] As shown, the SOC 300 can be coupled to various other circuitry of the UE 104. For example, the UE 104 can include various types of memory (e.g., including NAND flash memory 310), a connector interface 320 (e.g., for coupling to a computer system, docking station, charging station, etc.), a display 360, and wireless communication circuitry 330 (e.g., for LTE, LTE-A, LTE-V, 5G NR, CDMA2000, Bluetooth, Wi-Fi, GPS, etc.). The UE can also include at least one SIM device, and can include two SIM devices, each providing a respective international mobile subscriber identity (IMSI) and associated functionality.

[0086] As shown, the UE device 104 can include at least one antenna (and in various possibilities, multiple antennas, for example for MIMO and / or for implementing different wireless communication technologies) for performing wireless communication with base stations, access points, and / or other devices. For example, the UE device 104 can use the antenna 335 to perform wireless communication.

[0087] The UE 104 can also include and / or be configured for use with one or more user interface elements. User interface elements can include any of a variety of elements such as a display 360 (which can be a touchscreen display), a keyboard (which can be a discrete keyboard or can be implemented as part of a touchscreen display), a mouse, a microphone, and / or a speaker, one or more cameras, one or more buttons, and / or any of a variety of other elements capable of providing information to a user and / or receiving or interpreting user input.

[0088] As described herein, UE 104 may include hardware and software components for implementing features such as those described herein for performing more efficient vehicle-related communications. The processor 302 of UE device 104 may be configured to implement some or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). In other embodiments, processor 302 may be configured as a programmable hardware element such as a FPGA (Field-Programmable Gate Array) or as an ASIC (Application-Specific Integrated Circuit). Alternatively (or in addition), in conjunction with one or more of other components 300, 304, 306, 310, 320, 330, 335, 340, 350, 360, the processor 302 of UE device 104 may be configured to implement some or all of the features described herein, such as those described herein.

[0089] Figure 4 -Base station block diagram

[0090] Figure 4 Base station 102 is shown according to some embodiments (e.g., Figure 1 An exemplary block diagram of base station 102A in the diagram. Note that... Figure 4 The base station shown is merely one example of a possible base station. As illustrated, base station 102 may include a processor 404 capable of executing program instructions specific to base station 102. Processor 404 may also be coupled to a memory management unit (MMU) 440 or other circuitry or device, which may be configured to receive addresses from processor 404 and translate those addresses into locations in memory (e.g., memory 460 and read-only memory (ROM) 450).

[0091] Base station 102 may include at least one network port 470. The network port 470 may be configured to be coupled to a telephone network and provide access to the telephone network for multiple devices such as UE device 104.

[0092] Network port 470 (or an additional network port) may also be configured, or alternatively configured, to be coupled to a cellular network, such as the core network of a cellular service provider. The core network may provide mobility-related services and / or other services to multiple devices, such as UE device 104. In some cases, network port 470 may be coupled to a telephone network via the core network, and / or the core network may provide the telephone network (e.g., in other UE devices served by the cellular service provider).

[0093] In some implementations, the base station 102 can be a next generation base station, e.g., a 5G New Radio (5G NR) base station, or “gNB.” In such implementations, the base station 102 can connect to a traditional evolved packet core (EPC) network and / or to an NR core (NRC) network. Further, the base station 102 can be considered a 5G NR cell and can include one or more transition and reception points (TRPs). Moreover, a UE capable of operating according to 5G NR can connect to one or more TRPs within one or more gNBs.

[0094] The base station 102 can include at least one antenna 434, and possibly multiple antennas. The at least one antenna 434 can be configured to function as a wireless transceiver and can be further configured to communicate with UE devices 104 via the radio 430. The antenna 434 communicates with the radio 430 via a communication chain 432. The communication chain 432 can be a receive chain, a transmit chain, or both. The radio 430 can be configured to communicate via a variety of wireless communication standards including, but not limited to, LTE, LTE-A, LTE-V, GSM, UMTS, CDMA2000, 5G NR, Wi-Fi, etc.

[0095] The base station 102 can be configured to communicate wirelessly using multiple wireless communication standards. In some cases, the base station 102 can include multiple radios that can enable the base station 102 to communicate according to multiple wireless communication technologies. For example, as one possibility, the base station 102 can include an LTE radio for performing communications according to LTE and a 5G NR radio for performing communications according to 5G NR. In this case, the base station 102 can be capable of operating as both an LTE base station and a 5G NR base station. As another example, the base station 102 can include a 5G NR radio for performing communications according to 5G NR and a Wi-Fi radio for performing communications according to Wi-Fi. In this case, the base station 102 can be capable of operating as both a 5G NR base station and a Wi-Fi access point. As another possibility, the base station 102 can include a multi-mode radio capable of performing communications according to any of a plurality of wireless communication technologies, e.g., LTE and Wi-Fi, LTE and UMTS, LTE and CDMA2000, UMTS and GSM, etc.

[0096] As further described subsequently herein, the BS 102 can include hardware and software components for implementing or supporting an implementation of the features described herein. The processor 404 of the base station 102 can be configured, e.g., by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), to implement or support an implementation of part or all of the methods described herein. Alternatively, the processor 404 can be configured as a programmable hardware element, such as an FPGA (field programmable gate array), or as an ASIC (application specific integrated circuit), or a combination thereof. Alternatively (or additionally) in conjunction with one or more of the other components 430, 432, 434, 440, 450, 460, 470, the processor 404 of the base station 102 can be configured to implement or support an implementation of part or all of the features described herein.

[0097] Figure 5 - Sidelink resource management

[0098] As noted above, certain user equipment (or UE devices) can be capable of communicating directly with one another, i.e., without an intermediary infrastructure equipment such as a base station 102A or RSU 110A. This direct communication between two wireless devices, such as between two vehicles or between a vehicle UE and a pedestrian UE, is referred to as sidelink communication. In other words, two UE devices that perform peer-to-peer (direct) communication with one another can each utilize a “sidelink” interface to communicate directly with one another, and can be referred to as communicating over a sidelink channel.

[0099] In some existing implementations, a listen-before-talk (LBT) mechanism can be used to access a shared medium during sidelink communication to avoid collisions and to improve medium utilization efficiency. However, the LBT mechanism is not collision-free. In other words, the LBT mechanism does not guarantee collision-free transmission. Here, the term “collision” can refer to transmissions emanating from two or more wireless devices that are attempting to access the shared medium at about the same time. The shared medium can include unlicensed bands commonly used for Wi-Fi, Bluetooth, and other short-to-mid range communications (e.g., non-3GPP access).

[0100] In some implementations, to avoid collisions, a transmitter can reserve a periodic time slot for communication for a reservation period. In such implementations, if a collision occurs, the collision can persist for at least a portion of the reservation period (and, in the worst case, the duration of the reservation period) if the transmitter does not detect (or is unable to detect) the collision.

[0101] For example, vehicle-to-everything (V2X) communications (e.g., as specified by 3GPP TS 22.185 V.14.3.0) allow vehicles (e.g., mobile units within a vehicle, such as wireless devices contained within or currently contained within a vehicle and / or another transmitter contained or comprised in a vehicle) to communicate with various wireless devices. For example, as shown in Figure 5 a vehicle, such as vehicle 502a, can communicate with various devices (e.g., devices 502b-502f), such as roadside units (RSUs), infrastructure (V2I), networks (V2N), pedestrians (V2P), and / or other vehicles (V2V). Moreover, as shown, various devices within the V2X framework can communicate with other devices. V2X communications can utilize long-range (e.g., cellular) communications as well as short- to mid-range communications (e.g., non-cellular). In some contemplated implementations, non-cellular communications can use unlicensed bands as well as a dedicated spectrum at 5.9 GHz. Also, V2X communications can include unicast, multicast, groupcast, and / or broadcast communications. Each type of communication can employ an LBT mechanism.

[0102] As described above, in accordance with V2X communication protocols, a transmitter can reserve a periodic time slot within a reservation period. More specifically, to help prevent collisions from occurring on a shared sidelink channel, various UEs in a network (e.g., a V2X network) can perform sidelink resource management for both network-assisted resource management and autonomous (e.g., non-network assisted) resource management. In other words, various UE devices can operate to determine or schedule usage of sidelink resources for transmission to other UEs. In some embodiments, a UE, such as UE 106, can initiate a semi-persistent sidelink scheduling of resources. The UE can periodically broadcast a resource occupancy message (RO message). The RO message can include a resource block (RB) and / or subframe to be used (scheduled), a periodicity of the resource occupancy (e.g., reservation), and / or a remaining time of the resource occupancy (e.g., reservation). Moreover, in some embodiments, a maximum allowed channel occupancy time (T_max_COT) can be defined. In such embodiments, an initial remaining time of the resource occupancy can not exceed the maximum allowed channel occupancy time. In other words, the resource occupancy can only last for less than the maximum allowed channel occupancy time.

[0103] In some embodiments, when a UE enters a new system (e.g., a new group of UEs and / or a new location), then the UE can sense (listen) to the channel to collect existing UE RO messages to determine available resources in the new system. In other words, before transmitting a RO message upon entering a new group of UEs / areas (e.g., a group of UEs close to a sidelink communication), the UE can determine available resources via receiving RO messages from neighboring UEs. In some embodiments, upon expiration of resource occupation, the UE can determine available resources via receiving RO messages from neighboring UEs before transmitting a new RO message.

[0104] In some existing implementations, 5G NR V2X can include various scheduling modes. For example, 5G NR V2X Mode 2 can be designed for UE self-determination of sidelink transmission resources. 5G NR V2X Mode 2 includes various sub-modes, including:

[0105] Mode 2(a), in which a user equipment device (UE) autonomously selects sidelink resources for transmission;

[0106] Mode 2(b), in which a UE assists other UEs in sidelink resource selection;

[0107] Mode 2(c), in which a UE is configured with NR configured grants (e.g., network-defined semi-persistent grants) for sidelink transmission; and

[0108] Mode 2(d), in which a UE schedules sidelink transmissions for other UEs.

[0109] Further, due to the periodicity of V2X messaging, existing implementations of V2X can support semi-persistent scheduling (SPS), e.g., configured grants. For example, a semi-persistent resource in SPS can represent a set of discontinuous subframes with timely repeating resources on a specific repetition period. The semi-persistent resources can be scheduled across a set of discontinuous subframes with a subframe repetition period. Further, existing implementations of SPS (e.g., LTE V2X) and their corresponding resource allocation design are optimized for broadcast services. However, 5G NR V2X Mode 2 also supports both unicast and groupcast services. Therefore, there is a strong need to enhance methods that facilitate semi-persistent resource allocation for unicast and groupcast services in 5G NR V2X Mode 2.

[0110] In LTE V2X Rel-14, TX-UEs (UEs configured only to transmit in the sidelink channel and cannot receive in the sidelink channel) are supported by being configured to use either mode 2 random resource selection or mode 1 (base station controlled resource allocation). For NR V2X, TX-UEs can still support broadcast and groupcast with HARQ disabled. However, unicast is not supported since these TX-UEs cannot complete PC5-RRC connection setup.

[0111] In NR V2X R16, both mode 1 and mode 2 resource allocation schemes can be supported. The mode 2 resource allocation scheme can involve a transmitting UE selecting sidelink transmission resources based on its own sensing and resource selection procedure. In Rel-17 sidelink enhancements, the goal is to specify resource allocation by introducing the principles of Rel-14 LTE sidelink random resource selection and partial sensing to Rel-16 NR sidelink resource allocation mode 2.

[0112] As mentioned above, when using mode 2, some UEs can need to perform sensing operations periodically on the sidelink channel at a relatively high frequency in order to identify and utilize potential resources of other UEs for sidelink communication. Such active sensing can consume device resources, such as power, at a relatively high rate. However, the option of reducing the sensing operation to a partial sensing state, such as a UE only monitoring a subset of subframes it is receiving, still consumes energy. Further, the option of not performing sensing, e.g., random resource selection, can have a high probability of resource collision.

[0113] In some scenarios, resource allocation for pedestrian user equipment (PUE) or other power-limited UEs can be based on no sensing or partial sensing, where resources can be allocated randomly. On the other hand, for less power-limited UEs such as vehicle user equipment (VUE), full sensing can be employed. However, some lower-cost PUEs can lack the ability to receive sidelink communications from less power-limited VUEs regarding resource allocation.

[0114] One area that needs enhancement in transitioning from LTE V2X to NR V2X is resource allocation schemes for transmit-only user equipment (TX-UE). Currently, most resource allocation enhancement work has focused only on mode 2b, which does not include TX-UEs. More specifically, neither mode 2b nor 2d can be used with respect to TX-UEs, and since TX-UEs can lack a sidelink receiver, they cannot be directly coordinated by another UE. In this case, it can be necessary to coordinate TX-UEs via the Uu interface.

[0115] Figure 6 — Transmit-only UEs in V2X environments

[0116] As briefly described above, some lower-cost UEs tend to have reduced complexity and may not include a receiver compatible with sidelink communication. Therefore, some UEs (typically PUEs) may only be able to transmit to other UEs (such as VUEs or other UEs) (regarding sidelink communication) and may not be able to receive communication on the sidelink channel. UEs capable of transmitting on the sidelink channel but lacking the ability to receive on the sidelink channel are called transmit-only UEs (TX-UEs). It should be noted that transmit-only UEs are typically able to perform both transmit and receive operations on the Uu interface with the cellular base station, but these transmit-only UEs are only configured to transmit on the sidelink channel and lack sidelink receiver capability, making them unable to receive sidelink transmissions. Transmit-only UEs (TX-UEs) are an important aspect and demographic of pedestrian UEs (PUEs) interacting with vehicle UEs (VUEs) in V2X environments.

[0117] Due to this limitation, the TX-UE can proactively transmit sidelink communication signals to announce its presence, attempting to alert other road users. On the other hand, by not performing any sidelink reception operations, the transmitting UE gains the additional benefit of enhanced power savings. Furthermore, if a receiving UE learns that the transmitting UE is communicating with it, the receiving UE can similarly achieve enhanced power savings by not transmitting sidelink feedback communication to the transmitting UE.

[0118] Figure 6 The diagram illustrates transmit-only user equipment in a V2X environment according to some implementation schemes. For example, such as... Figure 6 As shown, only the TX UE 604 can transmit sidelink communication to the vehicle or coordinating UE 602, but cannot receive such sidelink communication from 602 due to a lack of sidelink receiving capability (i.e., a lack of sidelink receiver). However, the TX-UE can receive and transmit signaling from / to a base station (e.g., gNB) 606. In some respects, the TX-UE can transmit periodic sidelink messages that identify itself as a transmitting-only UE. Therefore, the VUE or coordinating UE may be able to utilize this information to minimize or eliminate unnecessary transmissions to the transmitting-only UE. As briefly described above, this could potentially lead to power savings for the VUE or coordinating UE by not consuming stored energy on these transmissions.

[0119] Figure 7A and Figure 7B — Resource conflicts in half-duplex and hidden nodes

[0120] Figure 7A and Figure 7B The document illustrates potential conflict issues that may arise with the UE. Figure 7A and Figure 7BExemplary collision scenarios in the middle can occur with respect to any UE (e.g., a UE capable of both sidelink transmission and reception operations) and can not be limited to only transmitting UE operations as described above.

[0121] Figure 7A The possibility of resource collision due to half-duplex operation of a UE is shown in accordance with some embodiments. In this example, a first UE (UE1) can not be able to decode sidelink control information (SCI) in a slot in which it is transmitting. In other words, UE1 can not be able to receive sidelink control information in a slot in which it is attempting to send data. Thus, in effect, UE1 can not be able to sense whether the slot for transmission to UE3 is an appropriate slot. In other words, since UE1 is not able to sense in that particular slot, it can not be aware of whether there is a collision of resources with UE3.

[0122] Figure 7B Another collision scenario, referred to as the hidden node problem, is shown. In this example, since UE2 is outside the coverage area in which UE1 is located, transmitting UE1 can not be aware of the interference of another transmitting UE2 from its sensing information. As shown, UE1 is transmitting a sidelink signal to UE3, where UE3 is close enough to UE1 to be within the coverage area in which UE1 is located. However, UE2 is outside the coverage area in which UE1 is located, and thus UE1 is not able to sense the transmission performed by UE2. Thus, UE1 is not able to detect the resources used by UE2 for the purpose of avoiding a collision. Thus, due to interference from UE2 (e.g., UE2 can be transmitting to UE3 in the same slot), reception of the transmission by UE3 for UE1 can fail. In other words, UE2 can be using the same transmission resources that UE1 is also trying to use to communicate with UE3, and this can result in a resource collision. Although a full sensing algorithm by RAN1 (radio layer 1) can allow UE1 to change to another slot when triggering resource reselection, the collision can persist as far as random resource selection is concerned. This can be due to the fact that LTE-V2X requires a UE to maintain a random resource selection procedure for a certain period of time. In other words, resource collisions in transmission / reception can occur even when a UE randomly selects resources. Thus, improvements in the art are desired.

[0123] Sidelink resource collision handling and resource allocation by user equipment coordination

[0124] In some embodiments, the V2X environment can include a base station, a RX-UE (e.g., a VUE), and a second UE (e.g., a PUE). As used herein, the term “RX-UE” refers to a UE that is capable of both receiving and transmitting on a sidelink channel. The RX-UE and the second UE can be fully capable of receiving and transmitting sidelink communications. Alternatively, in some aspects, the second UE can be a transmitting-only UE (TX-UE) as described above. The second UE is sometimes referred to herein as a “primary responsible UE” because the transmissions it performs result in the collision / interference problem.

[0125] The RX-UE can detect that the collisions that have occurred or will occur are due to the transmissions performed by the second UE (the primary responsible UE). These collisions can be due to the second UE’s inability to adequately sense the sidelink channel. Alternatively or in addition, the cause of these collisions can be the first UE’s inability to decode the data from the second UE’s sidelink transmissions. The RX-UE’s inability to decode the data can be due to a low SINR (signal to interference and noise ratio) after receiving sidelink control information (SCI) from the second UE. Since the second UE can not be able to receive resource allocation indications from the RX-UE (e.g., the second UE is a transmitting-only UE or TX-UE), the RX-UE can then send a report to a base station (e.g., a gNB) to inform the base station about the transmitter and / or receiver addresses and the problematic resource candidates. Alternatively, the second UE can be capable of transmitting and receiving sidelink communications. Thus, the RX-UE can then provide a feedback transmission directly to the second UE and / or can optionally send a report to the base station as described above.

[0126] In other embodiments, in response to a TX-UE sending a periodic sidelink message to a RX-UE to identify itself as a transmitting-only UE (i.e., lacking sidelink reception capability), the RX-UE can send a report to a base station. In some aspects, the report can also be sent by another coordinating UE (i.e., operating in mode 2d) that detects the collision.

[0127] The base station can then use the report to verify or determine the transmitter / receiver’s addresses (and the problematic candidate resources) and match them to the second UE. Additionally, the base station can be able to perform this verification based on the second UE having previously shared the expected sidelink transmissions to the base station in an earlier RRC transmission. In this RRC transmission, the second UE can have identified all possible destination IDs that the second UE attempts to transmit to. Next, the base station can send an RRCReconfigure message to the second UE to trigger the second UE to perform resource reselection.

[0128] During operation, a first UE (e.g., a VUE) can receive signaling from a second UE. In some instances, the second UE can be a transmit-only UE (TX-UE). As described above, when a VUE determines that it is communicating with a second UE and / or detects a resource collision due to an attempted transmission, the VUE (or other coordinating UE) can perform additional steps to avoid a later possible resource collision with the second UE. In some aspects, the UE can report the address and the resource in the collision to a base station. The base station can then utilize the report to validate the identity of the second UE and the candidate resource in the collision. In other words, given the existence of a transmit-only UE (second UE), the first UE or other coordinating UE can perform additional steps to reduce the likelihood of a resource collision.

[0129] Accordingly, the embodiments described herein contemplate a second UE (e.g., PUE) attempting to communicate sidelink with a first UE (e.g., VUE), where the first UE forwards information about the resource in the collision and the identifiers of the parties involved to a base station. The base station can use this information as a means to trigger the second UE to perform resource reselection of an appropriate sidelink transmission resource. In some instances, the second UE can be fully capable of transmitting and receiving sidelink communications. In other instances, the second UE can be a transmit-only UE (TX-UE) that can not be able to receive sidelink communications.

[0130] Figure 8 Inter-UE coordination and resource collision avoidance and resource allocation via a base station

[0131] Figure 8 Inter-UE coordination and resource collision avoidance and resource allocation via a base station are shown in accordance with some embodiments.

[0132] First, in step 802, a second UE (e.g., TX-UE) can report addressing or identifier information to a base station that the base station can use later when reporting a collision occurs for the base station to properly handle the collision and resource reselection trigger. For example, the second UE can report its <Source L2 ID, Destination L2 ID> pair to the base station (e.g., gNB). In other words, the second UE connected to the base station can report its own L2 (source) address to the base station. In addition, the report can contain information about an intended sidelink transmission and can also disclose all possible destination L2 IDs that the second UE attempts to transmit to. In doing so, the base station can be able to later utilize this information to determine / handle any potential resource collisions associated with this particular second UE. Additionally, this information can also help the base station to understand and evaluate unicast peers and match or check sidelink capabilities of the second UE or other UEs.

[0133] For example, in a scenario where a UE receives a transport block (TB) from another UE (e.g., via PSSCH), in order to perform feedback transmission, the receiving UE can need to know the identity of the UE that transmitted the TB. Therefore, when a UE transmits a TB to a receiving UE, an 8-bit source identity (ID) and a 16-bit destination ID are transmitted by the SCI stage 2. To avoid collision, resources for transmission can be determined by the source ID using the information conveyed by the SCI stage 2.

[0134] More specifically, Layer 1 (L1) IDs have incomplete address information conveyed in Sidelink Control Information (SCI). For example, L1 source ID is 8 bits of a 24-bit Layer 2 (L2) ID, and L1 destination ID is 16 bits of a 24-bit L2 ID. In an example of coordination between base station and UEs, a RX-UE (e.g., victim of hidden node or half duplex problem) can compare addresses by reporting its own L2 ID (destination ID) to the base station. Moreover, when a second UE initially sends SidelinkUEInformation to the base station, the second UE has indicated all of its intended destinations (including the RX-UE’s address). Then, the base station (e.g., gNB) can be able to verify or determine which other UE included the RX-UE address in its previous SidelinkUEInformation or RRC message. Thus, the base station can be able to precisely match the second UE based on the information provided by both the second UE and the RX-UE.

[0135] However, problems can arise in an example scenario where the RX-UE is not able to decode the MAC header transmitted by the second UE. In this case, the RX-UE can only report the L1 ID of the source UE (i.e., TX-UE). However, if the second UE reports its L2 ID to the base station in SidelinkUEInformation (not supported in 3GPP Rel-16 currently), the base station (e.g., gNB) can be able to match the detected 8 bits with the 8 bits in the second UE’s known 24-bit address. Additionally, if the second UE is a Mode 1 UE, the reported “conflicting” resources can also help the base station identify which UE caused the resource collision problem.

[0136] Moreover, in the transition from LTE V2X to NR V2X, a second UE that can perform sidelink can not disclose the source L2 address to the serving base station. More specifically, the second UE can report the transmit destination address but not its own address for RX operation. In this case, the base station can not be able to link the Uu address and the sidelink address, e.g., in 3GPP Rel-16.

[0137] SidelinkUEInformationNR excerpt:

[0138]

[0139] In the above excerpt, the TX-UE can include only the field "sl-DestinationIdentity-r16" in its report to the base station (e.g., gNB). The report can include one or more destination Layer 2 addresses, but can lack the source Layer 2 address that the TX-UE will use in its intended sidelink transmission.

[0140] Note that the base station can assign to the second UE an RNTI (Radio Network Temporary Identifier) used in the Uu interface (not in PC5) as a way to identify the second UE for later RRC messaging or triggering. The base station can also assign to the second UE another sidelink RNTI. However, both RNTIs cannot be used in the PC5 interface, but are used by the UE to monitor the PDCCH (Physical Downlink Control Channel) for Uu or SL grants assigned by the base station. Therefore, to correct this, it is proposed that the TX-UE reports both the source L2 ID and the destination L2 ID as a pair to the base station.

[0141] After reporting its <source L2 ID, destination L2 ID> pair to the base station, the second UE can proceed from step 802 to step 804 (for a Mode 1 UE) or alternatively to step 806 (for a Mode 2 UE).

[0142] In step 804, the Mode 1 UE (second UE) can receive a configured sidelink (SL) grant from the base station. In other words, the base station can at least partially coordinate resource allocation for the second UE. However, in the case where this Mode 1 UE utilizes resources scheduled by the base station, this resource allocation method is not 100% collision-free. For example, the base station (e.g., gNB) can use a dedicated resource pool for Mode 1. Alternatively, the base station can use a Mode 1-Mode 2 hybrid resource pool. However, even in the case of using a dedicated pool, the hidden terminal problem (as described above with reference to FIG. 7) still exists in the form of interfering UEs from neighboring cells or outside the coverage area. Also, in the case where two Mode 1 UEs are connected to two separate base stations, half-duplex and hidden node problems can occur.

[0143] Regarding Mode 1 UE sensing reporting in LTE-V2X R15, Mode 3 and / or Mode 4 resource pool sharing is supported by enabling Mode 3 UEs to report sensing results to the base station (e.g., eNB). For NR V2X, although Mode 1 UEs can reuse the LTE R15 baseline, the sensing results (e.g., a list of high-quality resource candidates) can not specifically enable the base station (e.g., gNB) to correct the resource collision problem for a specific UE. However, this problem can be addressed by allowing the UE to provide more accurate error reports (e.g., including <SL address, Sl resource, error level>), which can also allow the base station to trigger the second UE to perform resource reselection. Additionally, regarding the case of further study and impact involving RAN3 (Radio Access Network 3), and if the RX-UE and the second UE are in different cells, coordination between the base station and the UE can be necessary.

[0144] Alternatively, in step 806, the Mode 2 UE (second UE) can perform random resource selection from the transmit resource pool. In other words, since the second UE can not be able to receive feedback from the RX-UE (which can be a TX-UE, for example) that can indicate a resource collision, the second UE can randomly select a resource for transmitting a sidelink communication to the RX-UE. Since the resource has been randomly selected, there can still be a resource collision in the transmission between the second UE and the RX-UE.

[0145] From step 806 (Mode 2) or step 804 (Mode 1), the second UE can transmit a sidelink (SL) packet using the periodically or randomly selected resource in step 808. In other words, the second UE (e.g., PUE) can attempt to transmit a SL packet to a receiving UE (RX-UE) in order to communicate sidelink information to the RX-UE (e.g., VUE or coordinating UE). In other aspects, if the second UE is a TX-UE, it can also indicate its “no RX” status in the periodic SL message. In other words, the second UE (which can be a TX-UE in some instances) can broadcast a SL message to one or more UEs for which it does not have sidelink reception capability. When the RX-UE receives such a periodic message from the second UE, the RX-UE or another coordinating UE can adjust its own resource selection or attempt to use base station coordination, rather than sending a coordinating message back to the second UE (which would be ineffective due to the TX-UE’s lack of SL receiver itself). Moreover, as described above, this potential decision to forego sidelink feedback communication with the TX-UE can enable power savings for the RX-UE.

[0146] Accordingly, the RX-UE can detect the collision problem in step 810. In other words, the RX-UE can detect that two or more other UEs are transmitting on the same resource at the same time. The RX-UE can be able to detect the collision due to a low SINR (signal to interference and noise ratio) and not being able to decode the data in the received sidelink control information (SCI). Accordingly, the RX-UE can then identify or determine the addresses involved in the defective sidelink transmission. For example, as described above with reference to step 802, the RX-UE can not be able to decode the MAC header transmitted by the second UE, in which case the RX-UE can only be able to report the L1 ID of the source UE (i.e., the second UE). Alternatively, the RX-UE (e.g., an interfered party of a hidden node or half duplex problem) can report its own L2 ID (source ID) to the base station.

[0147] However, after determining the primary responsibility collision resource and address of the second UE, in step 812, the RX-UE can then report the L1 or L2 address and resource in the collision to the base station. Also, the RX-UE can further report the resource failure or collision problem to the base station. In some aspects, the report can be a specific, event triggered report (i.e., triggered by the determination of the resource collision), rather than a general report of the “health” or “usage map” of the resource pool. Further, the report can include the L1 ID involved and the problematic resource. Also, the sidelink measurement report can be re-used or a new Uu RRC message defined that will be used by the base station to appropriately allocate sidelink transmission resources to the second UE.

[0148] In step 814, the base station can then determine or verify that the L1 address and L2 address correspond to the problematic second UE. For example, as briefly described with respect to step 802, the base station can compare the L2 source ID (from the RX-UE) to the L2 destination ID originally provided by the second UE to the base station. Accordingly, the base station (e.g., gNB) can verify or determine which TX-UE included the RX-UE address in its earlier SidelinkUEInformation or RRC message. Accordingly, the base station can be able to precisely match the second UE based on the information provided by both the second UE and the RX-UE.

[0149] Proceeding to step 816, after identifying the primary UE, the base station may send an RRCReconfigure transmission to the second UE (the primary UE) to attempt to trigger resource reselection by the second UE. In other words, the base station may transmit signaling to the second UE providing instructions for reselecting appropriate sidelink transmission resources to utilize those resources in additional sidelink transmissions to the RX-UE. Additionally, the RRCReconfigure message for sidelinks may be enhanced to allow triggering mode 2 resource reselection. In some implementations, RRCReconfigure may indicate resource reselection in the form of a one-bit flag (configured per UE or per pool). Alternatively, in other respects, the fallback solution may involve the base station (e.g., gNB) reconfiguring the mode 2 pool and optionally excluding the problematic resources. This RRC pool reconfiguration can serve as an effective resource selection trigger.

[0150] Finally, in step 818, the second UE may receive an RRCReconfigure message from the base station. As described above, due to the detected conflict with the RX-UE, the RRCReconfigure message may instruct the second UE to select one or more different resources. In other words, the second UE may perform a resource reselection operation at least in part based on receiving a trigger signaling from the base station. This allows the second UE to select a new transmission resource group that will not cause the same type of conflict / interference that occurred previously. When performing resource reselection based on this message provided by the base station, the second UE can avoid resource conflicts when subsequently attempting to perform sidelink transmission to the RX-UE. Therefore, the second UE can then attempt to transmit sidelink communication to the RX-UE using these one or more reselected sidelink transmission resources, reducing conflict / interference issues.

[0151] As briefly described above, the process involving steps 802 to 804 and steps 808 to 818 can be applied to a Mode 1 UE. For example, as Figure 8 As shown, the UE can be either Mode 1 or Mode 2, and can proceed from step 804 to step 808, and can complete all steps up to 818 as a Mode 1 UE. For example, in some implementations, a Mode 1 UE may receive a new sidelink grant from the base station in the PDCCH channel (Physical Downlink Control Channel) (e.g., in step 816), which allocates one or more sidelink transmit resources to be used in the PC5 interface. Additionally or alternatively, in step 816, the newly configured sidelink grant may be given to the Mode 1 UE in an RRC (Radio Resource Control) message. Proceeding to step 818, the Mode 1 UE can then simply utilize the newly configured resources from the base station, rather than reselecting resources from the configured resource pool.

[0152] In summary, further reference is made to Figure 8 The above processes and steps illustrate an example of a second UE attempting to communicate with a RX-UE. The RX-UE can detect a collision in the attempted communication and optionally transmit collision-related information (including resource collision information and address information) to a base station. The base station can then use the information provided by the RX-UE and the information previously provided by the second UE to the base station (when the second UE attempted to communicate with the RX-UE) in order to identify the second UE and potentially trigger resource reselection of the second UE due to resource collision. As previously mentioned, in this example, the RX-UE can be fully capable of receiving and transmitting sidelink communications. Also, the second UE can also be fully capable of receiving and transmitting sidelink communications. However, in a very relevant case, the second UE can be a transmit-only UE that acquires support from the RX-UE (or other coordinating UE) and the base station in order to avoid potential resource collisions in sidelink transmissions between the second UE and the RX-UE due to its sensing and sidelink resource allocation limitations.

[0153] According to some embodiments, a user equipment (UE) includes at least one antenna, a radio operably coupled to the at least one antenna, and a processor operably coupled to the radio, the UE can be configured to determine information in response to receiving sidelink control information (SCI) from a second UE. The UE can be further configured to transmit the information to a base station, which can be used by the base station to determine an address of the second UE and one or more sidelink transmission resources used by the second UE on a sidelink channel. Finally, the UE can receive a sidelink communication from the second UE on the one or more determined sidelink transmission resources.

[0154] Other embodiments of the application will be described in the following paragraphs:

[0155] Some embodiments can relate to a user equipment (UE) device having at least one antenna for performing wireless communications, a radio, and a processing element coupled to the radio. The UE can perform at least some of the methods described herein.

[0156] Some embodiments can relate to a baseband processor having processing circuitry configured to perform at least some or all of the operations described above.

[0157] Some embodiments can relate to a base station configured to perform at least some or all of the operations described above.

[0158] It is well understood that, when using personal identifiable information, privacy policies and practices shall be followed that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled in a way to minimize risk of unintentional or unauthorized access or use, and battery should be clearly posted to users what the nature of the authorization is.

[0159] Embodiments of the present disclosure can be realized in any of various forms. For example, some embodiments can be realized as computer-implemented methods, computer-readable memory media, or computer systems. Other embodiments can be realized using one or more custom-designed hardware devices such as ASICs. Other embodiments can be realized using one or more programmable hardware elements such as FPGAs.

[0160] In some embodiments, a non-transitory computer-readable memory medium can be configured such that it stores program instructions and / or data, where if the program instructions are executed by a computer system, the computer system is caused to perform a method, such as any of the method embodiments described herein, or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets.

[0161] In some embodiments, a device (e.g., UE 104) can be configured to include a processor (or a set of processors) and a memory medium, where the memory medium stores program instructions, where the processor is configured to read and execute the program instructions from the memory medium, where the program instructions are executable to implement any of the various method embodiments described herein (or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets). The device can be realized in any of various forms.

[0162] Although the above embodiments have been described in considerable detail, variations and modifications are possible to those skilled in the art once they fully understand the disclosure. The disclosure is intended to be construed as including all such variations and modifications.

Claims

1. A method performed at a first user equipment (UE), comprising: detecting a collision of one or more resources caused by one or more sidelink transmissions by a second UE, wherein the second UE is a transmitting-only UE and is not capable of receiving sidelink transmissions; transmitting, to a base station, information about the detected collision, wherein the information about the detected collision is configured to cause the base station to reconfigure the second UE to stop using sidelink resources that caused the collision, wherein the information about the detected collision includes at least one of at least one identifier of the first UE and at least one identifier of the second UE, and is usable by the base station to verify that the second UE caused the collision based on a second UE’s identifier and an intended transmission destination identifier previously received from the second UE and based on the at least one of the at least one identifier of the first UE and the at least one identifier of the second UE.

2. The method of claim 1, wherein the information about the detected collision is configured to cause the base station to reconfigure the second UE to use one or more additional sidelink resources in place of the sidelink resources that caused the collision.

3. The method of claim 1, wherein the information about the detected collision is configured to cause the base station to trigger the second UE to perform sidelink resource reselection.

4. The method of claim 1, wherein the information about the detected collision is usable by the base station to determine that the second UE has previously communicated with the base station.

5. The method of claim 4, wherein the information about the detected collision includes at least one Layer 1 or Layer 2 identifier of the second UE, wherein the Layer 1 or Layer 2 identifier of the second UE is usable by the base station to assist in verifying that the second UE caused the collision.

6. The method of claim 4, wherein the information about the detected collision includes at least one Layer 1 or Layer 2 identifier of the first UE, wherein the Layer 1 or Layer 2 identifier of the first UE is usable by the base station to assist in verifying that the second UE caused the collision.

7. The method of claim 1, wherein the information about the detected collision includes at least in part at least one Layer 1 (L1) ID and at least one Layer 2 (L2) ID corresponding to the first UE and the second UE, and additional information corresponding to a resource collision.

8. A method performed at a base station, comprising: receiving, from a first user equipment (UE), information about one or more transmissions, wherein the information received from the first UE includes at least an intended transmission destination identifier, and the first UE is a transmitting-only UE and is not capable of receiving sidelink transmissions; receiving, from a second UE, additional information about the detected conflict, wherein the information about the detected conflict includes at least one of at least one identifier of the first UE and at least one identifier of the second UE; determining an identity of the first UE based at least in part on the first UE identifier received from the first UE and the intended transmission destination identifier and the at least one of the at least one identifier of the first UE and the at least one identifier of the second UE received from the second UE; and transmitting signaling to the first UE to instruct the first UE to stop using the sidelink resources that caused the conflict, wherein the signaling is based at least in part on determining the identity of the first UE.

9. The method of claim 8, wherein the signaling is configured to cause the base station to reconfigure the first UE to use one or more additional sidelink resources in place of the sidelink resources that caused the conflict.

10. The method of claim 8, wherein the signaling is configured to cause the base station to trigger the first UE to perform sidelink resource reselection.

11. The method of claim 8, wherein the information received from the first UE includes at least one or more Layer 2 identifiers, L2 IDs, of an intended transmission.

12. The method of claim 8, wherein transmitting signaling to the first UE to instruct the first UE to stop using the sidelink resources that caused the conflict comprises assigning the first UE a new sidelink grant or triggering resource reselection by the first UE.

13. The method of claim 8, wherein the base station is further configured to reconfigure a mode 2 resource pool based at least in part on receiving the additional information about the detected conflict.

14. The method of claim 8, wherein the signaling includes at least a one-bit flag.

15. The method of claim 14, wherein the base station is further configured to compare an 8-bit Ll ID to a 24-bit L2 ID.

16. An electronic device, comprising: at least one processor configured to cause a user equipment (UE) to perform the method of any of claims 1-7.

17. The electronic device of claim 16, further comprising: a radio operably coupled to the at least one processor.

18. An electronic device, comprising: at least one processor configured to cause a base station (BS) to perform the method of any of claims 8-15.

19. A non-transitory computer-readable storage medium storing program instructions executable by one or more processors to perform the method of any of claims 1-15.

Images