Method and apparatus for discontinuous reception operation of sidelink multicast / broadcast

Abstract

This disclosure relates to a 5G or 6G communication system for supporting higher data rates than 4G communication systems such as Long Term Evolution (LTE). Methods and apparatus in a wireless communication system are also included. A method for operating a first UE includes: determining whether to initiate an SL DRX operation for SL multicast / broadcast operation; identifying at least one of an SL DRX period length, an SL DRX start offset, and an SL DRX timer for the SL multicast / broadcast operation; identifying a time instance of the start of the SL DRX period based on at least one of a destination ID and the SL DRX start offset, wherein the time instance includes at least one of a time slot, a subframe, and a frame; and receiving a PSCCH and PSSCH from a second UE belonging to the destination ID based on at least one of the SL DRX period length, the SL DRX start offset, the destination ID, and the SL DRX timer.

Description

Technical Field

[0001] This disclosure generally relates to wireless communication systems, and more specifically, to discontinuous reception operations for sidelink multicast / broadcast operations in wireless communication. Background Technology

[0002] Given the successive generations of wireless communication development, these technologies have primarily been developed for human-oriented services such as voice calls, multimedia services, and data services. With the commercialization of 5G (fifth-generation) communication systems, the number of connected devices is expected to grow exponentially. Increasingly, these connected devices will connect to communication networks. Examples of connected things can include vehicles, robots, drones, home appliances, displays, smart sensors connected to various infrastructures, construction machinery, and factory equipment. Mobile devices are expected to evolve in various forms, such as augmented reality glasses, virtual reality headsets, and holographic devices. To deliver a wide range of services by connecting hundreds of billions of devices and things in the 6G (sixth-generation) era, efforts have been made to develop improved 6G communication systems. For these reasons, 6G communication systems are referred to as "beyond 5G" systems.

[0003] The 6G communication system, which is expected to be commercialized around 2030, will have peak data rates in the terabit (1,000 gigabit) bps range and radio latency of less than 100 μsec, making it 50 times faster than 5G communication systems and with 1 / 10 of their radio latency.

[0004] To achieve such high data rates and ultra-low latency, the implementation of 6G communication systems in the terahertz band (e.g., the 95 GHz to 3 THz band) has been considered. It is anticipated that technologies capable of ensuring signal transmission distance (i.e., coverage) will become even more critical, as path loss and atmospheric absorption in the terahertz band are more severe than those in the mmWave band introduced in 5G. It is necessary to develop radio frequency (RF) components, antennas, and novel waveforms that offer better coverage than orthogonal frequency division multiplexing (OFDM), beamforming and massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, and multi-antenna transmission technologies such as massive MIMO, as key technologies for ensuring coverage. Furthermore, new technologies for improving the coverage of terahertz band signals have been discussed, such as metamaterial-based lenses and antennas, orbital angular momentum (OAM), and reconfigurable smart surfaces (RIS).

[0005] Furthermore, to improve spectrum efficiency and overall network performance, the following technologies have been developed for 6G communication systems: full-duplex technology that enables uplink and downlink transmissions to use the same frequency resources at the same time; network technologies that utilize satellites, high-altitude platform stations (HAPS), etc., in an integrated manner; improved network architectures to support mobile base stations and achieve network operation optimization and automation; dynamic spectrum sharing technology that avoids conflicts through predictions based on spectrum usage; the use of artificial intelligence (AI) in wireless communication to improve overall network operation by leveraging AI from the design phase of 6G development and internalizing end-to-end AI support functions; and next-generation distributed computing technologies that overcome the limitations of UE computing capabilities through ultra-high-performance communication and computing resources accessible on the network, such as mobile edge computing (MEC) and the cloud. In addition, efforts are continuing to enhance connectivity between devices, optimize networks, promote the software-defined networking of network entities, and increase the openness of wireless communication by designing new protocols for use in 6G communication systems, developing mechanisms for implementing hardware-based secure environments and secure data usage, and developing technologies to maintain privacy.

[0006] The research and development of 6G communication systems (including human-to-machine (P2M) and machine-to-machine (M2M)) in hyper-connectivity is expected to enable the next hyper-connected experience. Specifically, services such as truly immersive extended reality (XR), high-fidelity mobile holograms, and digital replicas are expected to be available through 6G communication systems. Furthermore, services such as remote surgery for enhanced security and reliability, industrial automation, and emergency response will be provided via 6G communication systems, enabling these technologies to be applied to a wide range of sectors such as industry, healthcare, automotive, and home appliances. Summary of the Invention

[0007] Technical issues

[0008] Fifth-generation (5G), or new radio (NR) mobile communications, is currently gaining momentum amid global technological activity driven by a variety of candidate technologies from industry and academia. Potential enablers for 5G / NR mobile communications include massive MIMO technologies (from traditional cellular bands to high frequencies) that provide beamforming gain and support increased capacity, new waveforms that flexibly adapt to various services / applications with different requirements (e.g., new radio access technologies (RATs)), new multiple access schemes that support massive connectivity, and more.

[0009] Solution to the problem

[0010] In one embodiment, a first user equipment (UE) is provided in a wireless communication system. The first UE includes a processor configured to: determine whether to initiate an SL discontinuous (DRX) operation for sidelink (SL) multicast / broadcast operations; identify at least one of an SL DRX period length, an SL DRX start offset, and an SL DRX timer for the SL multicast / broadcast operation; and identify a time instance of the start of the SL DRX period based on at least one of a destination identifier (ID) and an SL DRX start offset, wherein the time instance includes at least one of a time slot, a subframe, and a frame. The first UE also includes a transceiver operatively connected to the processor, configured to receive a Physical Sidelink Control Channel (PSCCH) and a Physical Sidelink Shared Channel (PSSCH) from a second UE belonging to the destination ID based on at least one of the SL DRX period length, the SL DRX start offset, the destination ID, and the SL DRX timer.

[0011] In another embodiment, a method for a first UE in a wireless communication system is provided. The method of the first UE includes: determining whether to initiate an SL DRX operation for SL multicast / broadcast operation; identifying at least one of an SL DRX period length, an SL DRX start offset, and an SL DRX timer for the SL multicast / broadcast operation; identifying a time instance of the start of the SL DRX period based on at least one of a destination ID and an SL DRX start offset, wherein the time instance includes at least one of a time slot, a subframe, and a frame; and receiving a PSCCH and a PSSCH from a second UE belonging to the destination ID based on at least one of the SL DRX period length, the SL DRX start offset, the destination ID, and the SL DRX timer.

[0012] In yet another embodiment, a second UE is provided in a wireless communication system. The second UE includes a processor configured to: determine whether to initiate an SL DRX operation for SL multicast / broadcast operations; identify at least one of an SL DRX period length, an SL DRX start offset, and an SL DRX timer for the SL multicast / broadcast operation; and identify a time instance of the start of the SL DRX period based on at least one of a destination ID and the SL DRX start offset, wherein the time instance includes at least one of a time slot, a subframe, and a frame. The second UE also includes a transceiver operatively connected to the processor, configured to transmit a PSCCH and a PSSCH to a first UE belonging to a destination ID based on at least one of the SL DRX period length, the SL DRX start offset, the destination ID, and the SL DRX timer.

[0013] Other technical features will be apparent to those skilled in the art from the following figures, description and claims.

[0014] Before proceeding with the detailed description below, it may be advantageous to define certain words and phrases used throughout this patent document. The term “coupled” and its derivatives refer to any direct or indirect communication between two or more elements, regardless of whether these elements are physically in contact with each other. The terms “transmit,” “receive,” and “communicate,” and their derivatives encompass both direct and indirect communication. The terms “comprise” and “include,” and their derivatives mean inclusion without limitation. The term “or” is inclusive, meaning and / or. The phrase “associated with,” and its derivatives mean including, being included within, interconnected with, containing, being contained within, connected or connected to, coupled or coupled with, capable of communicating with, cooperating with, intertwined, juxtaposed, proximate, combined or combined with, having, possessing the nature of, related to, or relating to, etc. The term “controller” means any device, system, or part thereof that controls at least one operation. Such a controller may be implemented in hardware, or a combination of hardware and software and / or firmware. The functionality associated with any particular controller may be centralized or distributed, either local or remote. When used with a list of items, the phrase "at least one of..." means that different combinations of one or more of the listed items can be used, and only one item from the list may be required. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C.

[0015] Furthermore, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, associated data, or portions thereof suitable for implementation in suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium accessible by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drive, optical disc (CD), digital video disc (DVD), or any other type of storage. "Non-transitory" computer-readable media does not include wired, wireless, optical, or other communication links that transmit transient electrical or other signals. Non-transitory computer-readable media includes media in which data can be permanently stored and media in which data can be stored and subsequently overwritten, such as rewritable optical discs or erasable memory devices.

[0016] Definitions of certain other words and phrases are provided throughout this patent document. Those skilled in the art will understand that, in many instances (if not most), such definitions apply to both prior and future use of such defined words and phrases.

[0017] Beneficial effects of the invention

[0018] This disclosure relates to wireless communication systems, and more specifically, to discontinuous reception in wireless communication for sidelink multicast / broadcast operations. Attached Figure Description

[0019] To gain a more complete understanding of this disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals denote like parts:

[0020] Figure 1 An example wireless network according to an embodiment of the present disclosure is shown;

[0021] Figure 2 An example gNB according to an embodiment of the present disclosure is shown.

[0022] Figure 3 An example UE according to an embodiment of the present disclosure is shown;

[0023] Figure 4 and Figure 5 An example wireless transmission and reception path according to this disclosure is shown;

[0024] Figure 6 An example V2X communication on a side link according to an embodiment of this disclosure is illustrated;

[0025] Figure 7A The SL control plane radio control (RRC) protocol stack is shown;

[0026] Figure 7B The SL user plane data radio protocol stack is shown;

[0027] Figure 8 The resource (re)selection for an example TX UE for transmission according to an embodiment of this disclosure is illustrated;

[0028] Figure 9 The signaling flow of DRX for SL multicast / broadcast communication according to an embodiment of the present disclosure is shown;

[0029] Figure 10A A flowchart of a method for RX UE behavior according to an embodiment of the present disclosure is shown;

[0030] Figure 10B A flowchart of a method for RX UE behavior according to an embodiment of the present disclosure is shown;

[0031] Figure 11A A flowchart of a method for TX UE behavior according to an embodiment of the present disclosure is shown;

[0032] Figure 11B A flowchart of a method for TX UE behavior according to an embodiment of the present disclosure is shown; and

[0033] Figure 12 A flowchart is shown of a method for discontinuous reception of sidelink multicast / broadcast operations according to an embodiment of the present disclosure. Detailed Implementation

[0034] The following discussion in this patent document Figures 1 to 12 The various embodiments used to describe the principles of this disclosure are for illustrative purposes only and should not be construed as limiting the scope of this disclosure in any way. Those skilled in the art will understand that the principles of this disclosure can be implemented in any suitable system or apparatus.

[0035] The following documents are incorporated herein by reference, as if fully set forth herein: 3GPP TS38.211 v.16.2.0, “Physical channels and modulation”; 3GPP TS38.212 v.16.2.0, “Multiplexing and channel coding”; 3GPP TS38.213 v16.2.0, “NR; Physical Layer Procedures for Control”; 3GPP TS 38.214 v.16.2.0, “Physical layer procedures for data”; 3GPP TS 38.215 v.16.2.0, “Physical layer measurements”; 3GPP TS38.321 v16.1.0, “Medium Access Control (MAC) protocol”. 3GPP TS 38.322 v.16.1.0, “Media Access Control (MAC) Protocol Specification”; 3GPP TS 38.323 v.16.1.0, “Packet Data Convergence Protocol (PDCP) Specification”; 3GPP TS 38.331 v.16.1.0, “Radio Resource Control (RRC) Protocol Specification”; and 3GPP TS 37.324 v.16.1.0, “Service Data Adaptation Protocol (SDAP) Specification”.

[0036] The following Figures 1-3 Various embodiments are described in wireless communication systems and implementations using orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) communication technologies. Figures 1-3 The description does not imply any physical or architectural limitation on the ways in which different embodiments may be implemented. Different embodiments of this disclosure can be implemented in any suitable communication system.

[0037] Figure 1 An example wireless network according to an embodiment of this disclosure is shown. Figure 1 The embodiments of the wireless network shown are for illustrative purposes only. Other embodiments of the wireless network 100 may be used without departing from the scope of this disclosure.

[0038] like Figure 1 As shown, the wireless network includes gNB 101 (e.g., a base station, BS), gNB 102, and gNB 103. gNB 101 communicates with gNB 102 and gNB 103. gNB 101 also communicates with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or other data network.

[0039] gNB 102 provides wireless broadband access to network 130 to a first plurality of UEs within its coverage area 120. The first plurality of UEs includes UE 111, which may be located in a small business; UE 112, which may be located in an enterprise (E); UE 113, which may be located in a WiFi hotspot (HS); UE 114, which may be located in a first residence (R); UE 115, which may be located in a second residence (R); and UE 116, which may be a mobile device (M) such as a cellular phone, wireless laptop computer, wireless PDA, etc. gNB 103 provides wireless broadband access to network 130 to a second plurality of UEs within its coverage area 125. The second plurality of UEs includes UE 115 and UE 116. In some embodiments, one or more of gNBs 101-gNB 103 may communicate with each other and with UEs 111-UE 116 using 5G / NR, LTE, LTE-A, WiMAX, WiFi, or other wireless communication technologies.

[0040] Depending on the network type, the term "base station" or "BS" can refer to any component (or set of components) configured to provide wireless access to a network, such as a transmitting point (TP), a transmitting-receiving point (TRP), an enhanced base station (eNodeB or eNB), a 5G / NR base station (gNB), a macro cell, a femtocell, a WiFi access point (AP), or other wireless enabling devices. A base station can provide wireless access according to one or more wireless communication protocols, such as 5G / NR 3rd Generation Partnership Project (3GPP) NR, Long Term Evolution (LTE), Advanced LTE (LTE-A), High Speed ​​Packet Access (HSPA), Wi-Fi 802.11a / b / g / n / ac, etc. For convenience, the terms "BS" and "TRP" are used interchangeably in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Furthermore, depending on the network type, the term "user equipment" or "UE" can refer to any component such as a "mobile station," "subscriber station," "remote terminal," "wireless terminal," "receiving point," or "user device." For convenience, the terms “user equipment” and “UE” are used in this patent document to refer to a remote wireless device that wirelessly accesses a base station, whether the UE is a mobile device (such as a mobile phone or smartphone) or a device that is generally considered to be stationary (such as a desktop computer or vending machine).

[0041] The dashed lines show the approximate extent of coverage areas 120 and 125, which are shown as generally circular for illustrative and explanatory purposes only. It should be clearly understood that, depending on the configuration of the gNB and variations in the radio environment associated with natural and man-made obstacles, the coverage areas associated with the gNB (such as coverage areas 120 and 125) may have other shapes, including irregular shapes.

[0042] As described in more detail below, one or more of UEs 111-UE 116 include circuitry, programming, or a combination thereof for UE auxiliary information reporting in sidelink communications. In some embodiments, one or more of gNBs 101-gNB 103 include circuitry, programming, or a combination thereof for beam management and coverage enhancement for sidelink measurements in V2X communications.

[0043] although Figure 1 An example of a wireless network is shown, but more can be found on... Figure 1Various modifications can be made. For example, the wireless network can include any number of gNBs and any number of UEs in any suitable arrangement. Furthermore, gNB 101 can communicate directly with any number of UEs and provide these UEs with wireless broadband access to network 130. Similarly, each gNB 102-gNB 103 can communicate directly with network 130 and provide UEs with direct wireless broadband access to network 130. Additionally, gNB 101, gNB 102, and / or gNB 103 can provide access to other or additional external networks (such as external telephone networks or other types of data networks).

[0044] Figure 2 An example gNB 102 according to an embodiment of this disclosure is shown. Figure 2 The embodiment of gNB 102 shown is for illustrative purposes only, and Figure 1 The gNB 101 and gNB 103 can have the same or similar configurations. However, gNBs have a wide variety of configurations, and Figure 2 This disclosure is not intended to limit the scope of any particular implementation of gNB.

[0045] like Figure 2 As shown, gNB 102 includes multiple antennas 205a-205n, multiple RF transceivers 210a-210n, transmit (TX) processing circuitry 215, and receive (RX) processing circuitry 220. gNB 102 also includes a controller / processor 225, a memory 230, and a backhaul or network interface 235.

[0046] RF transceivers 210a-210n receive incoming RF signals, such as signals transmitted by a UE in network 100, from antennas 205a-205n. RF transceivers 210a-210n down-convert the incoming RF signals to generate IF or baseband signals. The IF or baseband signals are transmitted to RX processing circuitry 220, which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. RX processing circuitry 220 sends the processed baseband signals to controller / processor 225 for further processing.

[0047] The TX processing circuit 215 receives analog or digital data (such as voice data, network data, email, or interactive video game data) from the controller / processor 225. The TX processing circuit 215 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. RF transceivers 210a-210n receive the outgoing processed baseband or IF signal from the TX processing circuit 215 and up-convert the baseband or IF signal into an RF signal transmitted via antennas 205a-205n.

[0048] The controller / processor 225 may include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller / processor 225 may control the reception of forward channel signals and the transmission of reverse channel signals via RF transceivers 210a-210n, RX processing circuitry 220, and TX processing circuitry 215, based on known principles. The controller / processor 225 may also support additional functions, such as more advanced wireless communication capabilities. For example, the controller / processor 225 may support beamforming or directional routing operations in which outgoing / incoming signals from / to multiple antennas 205a-205n are weighted differently to effectively direct outgoing signals in a desired direction. Any of a wide variety of other functions may be supported by the controller / processor 225 within the gNB 102.

[0049] The controller / processor 225 is also capable of executing programs and other processes, such as an operating system, residing in the memory 230. The controller / processor 225 can move data into or out of the memory 230 as needed for the execution process.

[0050] The controller / processor 225 is also coupled to a backhaul or network interface 235. The backhaul or network interface 235 allows the gNB 102 to communicate with other devices or systems via a backhaul connection or over a network. Interface 235 can support communication via any suitable wired or wireless connection(s). For example, when the gNB 102 is implemented as part of a cellular communication system (such as a system supporting 5G / NR, LTE, or LTE-A), interface 235 can allow the gNB 102 to communicate with other gNBs via a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, interface 235 can allow the gNB 102 to communicate via a wired or wireless local area network or via a wired or wireless connection to a larger network (such as the Internet). Interface 235 includes any suitable architecture supporting communication via wired or wireless connections, such as Ethernet or RF transceivers.

[0051] Memory 230 is coupled to controller / processor 225. A portion of memory 230 may include RAM, and another portion of memory 230 may include flash memory or other ROM.

[0052] although Figure 2 An example of gNB 102 is shown, but it is possible to compare it with other models. Figure 2 Various changes can be made. For example, gNB 102 can include any number of Figure 2Each component is shown. As a specific example, an access point may include multiple interfaces 235, and a controller / processor 225 may support discontinuous reception for sidelink multicast / broadcast operations. As another specific example, although shown as a single instance including TX processing circuitry 215 and a single instance including RX processing circuitry 220, gNB 102 may include multiple instances of each (such as one per RF transceiver). Furthermore, components may be combined, further subdivided, or omitted. Figure 2 It includes various components and allows for the addition of additional components as needed.

[0053] Figure 3 An example UE 116 according to an embodiment of this disclosure is shown. Figure 3 The embodiment of UE 116 shown is for illustrative purposes only. Figure 1 UEs 111-UE 115 can have the same or similar configurations. However, UEs have a wide variety of configurations, and Figure 3 This disclosure is not intended to limit the scope of any particular implementation of the UE.

[0054] like Figure 3 As shown, UE 116 includes an antenna 305, a radio frequency (RF) transceiver 310, a TX processing circuit 315, a microphone 320, and a receive (RX) processing circuit 325. UE 116 also includes a speaker 330, a processor 340, an input / output (I / O) interface (IF) 345, a touchscreen 350, a display 355, and a memory 360. The memory 360 includes an operating system (OS) 361 and one or more applications 362.

[0055] RF transceiver 310 receives incoming RF signals transmitted by a gNB of network 100 from antenna 305. RF transceiver 310 down-converts the incoming RF signals to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is transmitted to RX processing circuitry 325, which generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. RX processing circuitry 325 sends the processed baseband signal to speaker 330 (e.g., for voice data) or processor 340 for further processing (e.g., for web browsing data).

[0056] The TX processing circuit 315 receives analog or digital voice data from the microphone 320 or other outgoing baseband data (such as network data, email, or interactive video game data) from the processor 340. The TX processing circuit 315 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 310 receives the outgoing processed baseband or IF signal from the TX processing circuit 315 and up-converts the baseband or IF signal into an RF signal transmitted via the antenna 305.

[0057] Processor 340 may include one or more processors or other processing devices and executes OS 361 stored in memory 360 to control the overall operation of UE 116. For example, processor 340 may control the reception of forward channel signals and the transmission of reverse channel signals through RF transceiver 310, RX processing circuitry 325 and TX processing circuitry 315 according to known principles. In some embodiments, processor 340 includes at least one microprocessor or microcontroller.

[0058] Processor 340 is also capable of executing other processes and programs residing in memory 360, such as processes for discontinuous reception for sidelink multicast / broadcast operations. Processor 340 can move data into or out of memory 360 as needed for the execution of the process. In some embodiments, processor 340 is configured to execute application 362 based on OS 361 or in response to signals received from gNB or operator. Processor 340 is also coupled to I / O interface 345, which provides UE 116 with the ability to connect to other devices, such as laptop computers and handheld computers. I / O interface 345 is the communication path between these accessories and processor 340.

[0059] The processor 340 is also coupled to the touchscreen 350 and the display 355. The operator of the UE 116 can use the touchscreen 350 to input data into the UE 116. The display 355 may be a liquid crystal display, a light-emitting diode display, or other display capable of displaying text (such as from a website) and / or at least limited graphics.

[0060] The memory 360 is coupled to the processor 340. A portion of the memory 360 may include random access memory (RAM), and another portion of the memory 360 may include flash memory or other read-only memory (ROM).

[0061] although Figure 3 An example of UE 116 is shown, but it is possible to modify it. Figure 3 Make various changes. For example, you can combine, further subdivide, or omit. Figure 3The processor 340 can be divided into various components, and additional components can be added as needed. As a specific example, the processor 340 can be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Furthermore, although... Figure 3 The UE 116 is shown configured as a mobile phone or smartphone, but the UE can be configured to operate as other types of mobile or stationary devices.

[0062] To meet the increased demand for wireless data services since the deployment of 4G communication systems and to enable various vertical applications, 5G / NR communication systems have been developed and are currently being deployed. The implementation of 5G / NR communication systems in higher frequency (mmWave) bands (e.g., 28 GHz or 60 GHz bands) is considered for higher data rates, or in lower frequency bands (such as 6 GHz) for robust coverage and mobility support. To reduce radio wave propagation loss and increase transmission distance, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive MIMO technologies are discussed in 5G / NR communication systems.

[0063] In addition, in 5G / NR communication systems, development is underway to improve system networks based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communication, coordinated multipoint (CoMP), and receiver interference cancellation.

[0064] The discussion of 5G systems and associated frequency bands is provided for reference, as certain embodiments of this disclosure can be implemented in 5G systems. However, this disclosure is not limited to 5G systems or associated frequency bands, and embodiments of this disclosure can be utilized in conjunction with any frequency band. For example, aspects of this disclosure can also be applied to 5G communication systems, 6G, or even higher-version deployments that can use terahertz (THz) frequency bands.

[0065] A communication system includes a downlink (DL) which refers to the transmission from a base station or one or more transmitting points to a UE, and an uplink (UL) which refers to the transmission from a UE to a base station or one or more receiving points.

[0066] The time unit used for DL ​​signaling or UL signaling on a cell is called a time slot, and it may include one or more symbols. Symbols can also serve as additional time units. Frequency (or bandwidth (BW)) units are called resource blocks (RBs). An RB includes multiple subcarriers (SCs). For example, a time slot may have a duration of 0.5 milliseconds or 1 millisecond, include 14 symbols, and an RB may include 12 SCs with an inter-SC spacing of 15 kHz or 30 kHz, and so on.

[0067] DL signals include data signals that transmit information content, control signals that transmit DL control information (DCI), and reference signals (RS), also known as pilot signals. The gNB transmits data information or DCI via the corresponding Physical DL Shared Channel (PDSCH) or Physical DL Control Channel (PDCCH). PDSCH or PDCCH can be transmitted on a variable number of time slot symbols, each comprising one time slot symbol. For simplicity, the DCI format used to schedule PDSCH reception by the UE is referred to as the DL DCI format, and the DCI format used to schedule transmission from the UE's Physical Uplink Shared Channel (PUSCH) is referred to as the UL DCI format.

[0068] The gNB transmits one or more types of RS, including Channel State Information RS (CSI-RS) and Demodulation RS (DMRS). CSI-RS is primarily intended for the UE to perform measurements and provide CSI to the gNB. For channel measurements, the Non-Zero Power CSI-RS (NZP CSI-RS) resource is used. For Interference Measurement Reporting (IMR), the CSI Interference Measurement (CSI-IM) resource associated with the Zero Power CSI-RS (ZP CSI-RS) configuration is used. The CSI process includes both NZP CSI-RS and CSI-IM resources.

[0069] The UE can determine the CSI-RS transmission parameters via DL control signaling or higher-level signaling (such as Radio Resource Control (RRC) signaling) from the gNB. The transmission instance of CSI-RS can be indicated by DL control signaling or configured by higher-level signaling. DMRS is transmitted only in the BW of the corresponding PDCCH or PDSCH, and the UE can use DMRS to demodulate data or control information.

[0070] Figure 4 and Figure 5Example wireless transmit and receive paths according to this disclosure are illustrated. In the following description, transmit path 400 may be described as being implemented in a gNB (such as gNB 102), and receive path 500 may be described as being implemented in a UE (such as UE 116). However, it will be understood that receive path 500 may be implemented in a gNB, and transmit path 400 may be implemented in a UE. In some embodiments, receive path 500 is configured to support sidelink measurements in V2X communication, as described in embodiments of this disclosure.

[0071] like Figure 4 The transmission path 400 shown includes a channel coding and modulation block 405, a serial-to-parallel (S-to-P) block 410, an N-size inverse fast Fourier transform (IFFT) block 415, a parallel-to-serial (P-to-S) block 420, a cyclic prefix addition block 425, and an up-converter (UC) 430. For example... Figure 5 The receiver path 500 shown includes a downconverter (DC) 555, a cyclic prefix removal block 560, a serial-to-parallel (S-to-P) block 565, a fast Fourier transform (FFT) block of size N, a parallel-to-serial (P-to-S) block 575, and a channel decoding and demodulation block 580.

[0072] As shown in Figure 400, the channel coding and modulation block 405 receives a set of information bits, applies coding (such as low-density parity-check (LDPC) coding), and modulates the input bits (such as using quadrature phase shift keying (QPSK) or quadrature amplitude modulation (QAM)) to generate a frequency domain modulated symbol sequence.

[0073] Serial-to-parallel block 410 converts (e.g., demultiplexes) serial modulated symbols into parallel data to generate N parallel symbol streams, where N is the IFFT / FFT size used in gNB 102 and UE 116. IFFT block 415 of size N performs IFFT operations on the N parallel symbol streams to generate a time-domain output signal. Parallel-to-serial block 420 converts (e.g., multiplexes) the parallel time-domain output symbols from IFFT block 415 of size N to generate a serial time-domain signal. Cyclic prefix addition block 425 inserts a cyclic prefix into the time-domain signal. Upconverter 430 modulates (e.g., upconverts) the output of cyclic prefix addition block 425 to an RF frequency for transmission via a wireless channel. The signal may also be filtered in baseband before conversion to the RF frequency.

[0074] The transmitted RF signal from gNB 102 reaches UE 116 after passing through the wireless channel, and the operation opposite to that at gNB 102 is performed at UE 116.

[0075] like Figure 5As shown, downconverter 555 downconverts the received signal to the baseband frequency, and cyclic prefix removal block 560 removes the cyclic prefix to generate a serial time-domain baseband signal. Serial-to-parallel block 565 converts the time-domain baseband signal into a parallel time-domain signal. FFT block 570 of size N performs an FFT algorithm to generate N parallel frequency-domain signals. Parallel-to-serial block 575 converts the parallel frequency-domain signals into a sequence of modulated data symbols. Channel decoding and demodulation block 580 demodulates and decodes the modulated symbols to recover the original input data stream.

[0076] Each of gNB 101-103 can be implemented as follows Figure 4 The transmission path 400 shown is similar to transmitting to UEs 111-116 in the downlink, and can be implemented as follows: Figure 5 The receive path 500 shown is similar to that received from UE 111-116 in the uplink. Similarly, each of UE 111-116 may implement a transmit path 400 for transmitting to GNB 101-103 in the uplink, and may implement a receive path 500 for receiving from gNB 101-103 in the downlink.

[0077] Figure 4 and Figure 5 Each component can be implemented using only hardware or a combination of hardware and software / firmware. As a specific example, Figure 4 and Figure 5 At least some components can be implemented in software, while others can be implemented in configurable hardware or a hybrid of software and configurable hardware. For example, FFT block 570 and IFFT block 515 can be implemented as configurable software algorithms, where the value of size N can be modified depending on the implementation method.

[0078] Furthermore, although described as using FFT and IFFT, this is for illustrative purposes only and should not be construed as limiting the scope of this disclosure. Other types of transforms, such as the Discrete Fourier Transform (DFT) and Inverse Discrete Fourier Transform (IDFT) functions, can be used. It will be understood that for the DFT and IDFT functions, the value of variable N can be any integer (such as 1, 2, 3, 4, etc.), while for the FFT and IFFT functions, the value of variable N can be any integer that is a power of 2 (such as 1, 2, 4, 8, 16, etc.).

[0079] although Figure 4 and Figure 5 An example of a wireless transmit and receive path is shown, but it is possible to modify it further. Figure 4 and Figure 5 Make various changes. For example, Figure 4 and Figure 5The various components can be combined, further subdivided, or omitted, and additional components can be added as needed. Furthermore, Figure 4 and Figure 5 This section aims to illustrate examples of the types of transmit and receive paths that can be used in a wireless network. Any other suitable architecture can be used to support wireless communication in a wireless network.

[0080] In the 3GPP wireless standards, NR has been discussed as a 5G wireless communication technology. One of the NR features being discussed is V2X.

[0081] Figure 6 An example V2X communication over a side link 600 according to an embodiment of this disclosure is shown. Figure 6 The embodiment of V2X communication on side link 600 shown is for illustrative purposes only.

[0082] Figure 6 This illustrates an example scenario of vehicle-to-vehicle communication. Two or more vehicles can send and receive data / control signals over a direct link / interface between them. In 3GPP, a direct link / interface between vehicles or between a vehicle and other things is called a sidelink (SL). Note that... Figure 6 The scenario described illustrates a situation where vehicles can still communicate with the gNB to obtain SL resources, SL radio bearer configurations, etc. However, even without interaction with the gNB, vehicles can still communicate with each other on the SL. In this case, SL resources, SL radio bearer configurations, etc., are pre-configured (e.g., via a V2X server or any other core network entity).

[0083] In the 3GPP wireless standards, NR is discussed as 5G wireless communication. One of the NR features being discussed is Vehicle-to-Everything (V2X).

[0084] Figure 6 An example V2X communication over a side link 600 according to an embodiment of this disclosure is shown. Figure 6 The embodiment of V2X communication on side link 600 shown is for illustrative purposes only.

[0085] Figure 6 This describes an example scenario of vehicle-to-vehicle communication. Two or more vehicles can send and receive data / control signals over a direct link / interface between them. In the 3GPP standard, a direct link / interface between vehicles or between vehicles and other things (e.g., pedestrian equipment or any equipment related to the traffic system) or other things is named SL.

[0086] Figure 6This describes an example scenario where vehicles communicate with each other and are within the coverage of an NR network. Vehicles communicate with the gNB to obtain SL-related resource information (e.g., SL resource pool configuration), SL radio bearer configuration (SLMAC, RLC, PDCP, SDAP, RRC-related configurations), etc.

[0087] Once the vehicle obtains its SL configuration from the gNB, the vehicles send / receive data / controls to each other on the SL. Note that even without interaction with the gNB (e.g., when the vehicle is outside the coverage of the NR network), the vehicles can still communicate with each other on the SL. In this case, SL resources, SL radio bearer configurations, etc., are pre-configured (e.g., via a V2X server or any other core network entity). For more detailed V2X scenarios and studies, please refer to the 3GPP standard specifications.

[0088] For SL communication, as specified in the 3GPP standard, the radio interface layer 1 / layer 2 / layer 3 (L1 / L2 / L3) protocols include physical (PHY) protocol, MAC, RLC, PDCP, RRC and SDAP.

[0089] Figure 7A The SL control plane radio control (e.g., RRC) protocol stack 700 is shown. Figure 7A The embodiment of the SL control plane RRC protocol stack 700 shown is for illustrative purposes only.

[0090] Figure 7B The SL user plane data radio protocol stack 750 is shown. Figure 7B The embodiment of the SL user plane data radio protocol stack 750 shown is for illustrative purposes only.

[0091] Figure 7A and Figure 7B Examples of the SL control plane radio protocol stack (for SL-RRC) and the SL user plane data radio protocol stack for NR SL communication are shown.

[0092] exist Figure 7A The SL control plane radio protocol stack (e.g., RRC) is shown in the figure, and... Figure 7B The image shows the SL user plane data radio protocol stack.

[0093] The physical protocol layer processes physical layer signals / channels and physical layer procedures (e.g., physical layer channel structure, physical layer signal encoding / decoding, SL power control procedures, SL CSI related procedures). The main physical SL channels and signals are defined as follows: (1) Sidelink Control Information (SCI) in PSCCH and / or PSSCH indicates the resources and other transmission parameters used by the UE for data PSSCH; (2) Transport Block (TB) itself and CSI feedback information, etc., in data PSSCH; (3) Physical Sidelink Feedback Channel (PSFCH) sends Hybrid Automatic Repeat Request (HARQ) feedback from the UE, which is the intended recipient of PSSCH transmission, to the UE performing the transmission on the sidelink; (4) Sidelink synchronization signals include the sidelink primary synchronization signal and the sidelink secondary synchronization signal (S-PSS, S-SSS); and (5) Physical Sidelink Broadcast Channel (PSBCH) indicates the necessary system information required for SL operation.

[0094] The MAC protocol layer performs packet filtering (e.g., determining whether a received packet is actually destined for the UE based on the L2 source and destination IDs in the MAC header), SL carrier / resource pool / resource (re)selection within the resource pool, priority handling between the SL and UL for a given UE, SL logical channel priority sorting, corresponding packet multiplexing (e.g., multiplexing multiple MAC Service Data Units (SDUs) into a given MAC Protocol Data Unit (PDU)), and SL HARQ retransmission / reception.

[0095] The RLC protocol layer performs RLC SDU segmentation / SDU reassembly, RLC SDU segment resegmentation, and error correction via ARQ (only for AM data transmission). The PDCP protocol layer performs header compression / decompression, encryption and / or integrity protection, deduplication detection, reordering, and ordered and unordered packet delivery to upper layers.

[0096] The RRC protocol layer performs the transmission of SL-RRC messages between peer UEs, the maintenance and release of SL-RRC connections between two UEs, and the detection of SL radio link failures in SL-RRC connections. The SDAP protocol layer performs the mapping between Quality of Service (QoS) streams and SL data radio bearers.

[0097] SCI on PSCCH and / or PSSCH includes two SCI formats. The first-stage SCI format is SCI format 1-A in PSCCH, and the second-stage SCI format is SCI format 2-A and / or SCI format 2-B in PSSCH. Each SCI format has the following information.

[0098] SCI format 1-A is used for scheduling the second-stage SCI on PSSCH and PSSCH.

[0099] The following information is sent via SCI format 1-A: (1) Priority - 3 bits, as defined in the 3GPP standard specification; (2) Frequency resource allocation - when the value of the higher-level parameter sl-MaxNumPerReserve is configured to 2. Bits, otherwise, when the value of the higher-level parameter sl-MaxNumPerReserve is configured to 3. (3) Time resource allocation - 5 bits when the higher-level parameter sl-MaxNumPerReserve is configured to 2, otherwise 9 bits when the higher-level parameter sl-MaxNumPerReserve is configured to 3, as defined in the 3GPP standard specification; (4) Resource reservation period - Bits, as defined in the 3GPP standard specification, where N is configured if the higher-level parameter sl-MultiReserveResource is selected. rsv_period It is the number of entries in the higher-level parameter sl-ResourceReservePeriodList; otherwise, it is 0 bits; (5) DMRS mode - Bits, as defined in the 3GPP standard specification, where N pattern This is the number of DMRS modes configured by the higher-level parameter sl-PSSCH-DMRS-TimePatternList; if sl-PSSCH-DMRS-TimePatternList is not configured, it is 0 bits; (6) Second-stage SCI format - 2 bits, as shown in Table 1; (7) Beta_offset indicator - 2 bits, as provided by the higher-level parameter sl-BetaOffsets2ndSCI and the table shown in Table 2; (8) DMRS port number - 1 bit, as defined in the table shown in Table 3; (9) Modulation and coding scheme - 5 bits, as defined in the 3GPP standard specification; (10) Additional MCS Table indicator - as defined in the 3GPP standard specification: 1 bit if one MCS table is configured by the higher-level parameter sl-Additional-MCS-Table; 2 bits if two MCS tables are configured by the higher-level parameter sl-Additional-MCS-Table; otherwise, 0 bits; (11) PSFCH overhead indicator - as defined in the 3GPP standard specification: 1 bit if the higher-level parameter sl-PSFCH-Period = 2 or 4; otherwise, 0 bits; and / or (12) Reserved - the number of bits determined by the higher-level parameter sl-NumReservedBits, with its value set to zero.

[0100] Table 1. Second-stage SCI format

[0101] The second stage of SCI format field values Second-stage SCI format 00 SCI Format 2-A 01 SCI Format 2-B 10 reserve 11 reserve

[0102] Table 2. Mapping of Beta_offset indicator values ​​to indices

[0103]

[0104]

[0105] Table 3. (Multiple) DMRS Port Numbers

[0106] The value of the DMRS port number field Antenna port 0 1000 1 1000 and 1001

[0107] SCI format 2-A in PSSCH is used for PSSCH decoding. It has HARQ operation when the HARQ-ACK information includes ACK or NACK or when there is no HARQ-ACK information feedback.

[0108] Send the following information via SCI format 2-A: (1) HARQ process number - (1) New Data Indicator - 1 bit, as defined in the 3GPP standard specification; (2) Redundancy Version - 2 bits, as defined in the 3GPP standard specification; (3) Source ID - 8 bits, as defined in the 3GPP standard specification; (4) Destination ID - 16 bits, as defined in the 3GPP standard specification; (5) HARQ Feedback Enable / Disable Indicator - 1 bit, as defined in the 3GPP standard specification; (6) Propagation Type Indicator - 2 bits, as shown in Table 4; and / or (8) CSI Request - 1 bit, as defined in the 3GPP standard specification.

[0109] Table 4. Propagation Type Indicators

[0110] Value of propagation type indicator Types of propagation 00 broadcast 01 multicast 10 unicast 11 reserve

[0111] The SCI format 2-B in PSSCH is used for PSSCH decoding. It has HARQ operation when the HARQ-ACK information only includes NACK or when there is no HARQ-ACK feedback.

[0112] Send the following information via SCI format 2-B: (1) HARQ process number - (1) New data indicator - 1 bit, as defined in the 3GPP standard specification; (2) Redundancy version - 2 bits, as defined in the 3GPP standard specification; (3) Source ID - 8 bits, as defined in the 3GPP standard specification; (4) Destination ID - 16 bits, as defined in the 3GPP standard specification; (5) HARQ feedback enable / disable indicator - 1 bit, as defined in the 3GPP standard specification; (6) Area ID - 12 bits; and / or (8) Communication range requirements, as defined in the 3GPP standard specification.

[0113] Figure 8 The resource (re)selection for an example TX UE for transmission 800 is shown according to an embodiment of this disclosure. Figure 8 The embodiment shown in the diagram for resource (re)selection for TX UE of transmission 800 is for illustrative purposes only.

[0114] like Figure 8 As shown, resource selection involves two steps. It can be assumed that the UE triggers resource selection at time n. First, the UE performs channel sensing during the sensing window to identify the observed available SL channels. Channel sensing is actually performed before time n (e.g., the sensing window runs from time (n-T0) to time (n-Tproc,0)). Then, during the resource selection window, the UE selects the actual resource(s) for transmission from the observed available SL channels. For example, the resource selection window runs from time (n+T1) to time (n+T2).

[0115] The 3GPP standard specification supports and defines basic SL communication functions. For Rel-17, more enhancements are planned for SL, one of which is the introduction of SL DRX (Discontinuous Receive) operation. Note that in the 3GPP standard specification Rel-16, UE DRX operation is only specified for DL ​​(Downlink). Detailed DL DRX operation is specified in 3GPP standard specifications (e.g., MAC).

[0116] Compared to DL DRX, SL multicast / broadcast communication presents new challenges (e.g., there is no SL-RRC / PC5-RRC protocol for SL multicast / broadcast communication, while all parameters of DL DRX are configured by dedicated RRC messages (e.g., RRC connection reconfiguration); SL ​​multicast / broadcast is many-to-many (M-to-M) communication, while DL / UL communication is essentially one-to-one (1-to-1) communication, etc.). A DRX mechanism specific to SL multicast / broadcast is provided here.

[0117] Figure 9 Signaling flow 900 for DRX for SL multicast / broadcast communication according to an embodiment of the present disclosure is shown. Figure 9The embodiment of signaling flow 900 shown is for illustrative purposes only. Figure 9 One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0118] like Figure 9 As shown, TX UE#1 and TX UE#2 are UEs with data to send, therefore they send the corresponding PSCCH and PSSCH on the SL. RX UE is the UE that receives the PSCCH and PSSCH on the SL. Note that TX UE#1 and TX UE#2 can also be RX UEs when a UE receives the PSCCH and PSSCH of other UEs. Also note that it is assumed that all TX UE#1, TX UE#2, and RX UEs belong to the same SL multicast / broadcast group. Members in the same SL multicast / broadcast group share the same group ID, which can be expressed by the same L2 destination ID in the MAC header, or the L1 destination ID in the SCI of the PSCCH and / or PSSCH, or the upper-layer (V2X layer or application layer) link ID.

[0119] like Figure 9 As shown, in T601, T602, and T603, the gNB notifies all UEs of SL DRX-related configurations via system information or RRC-specific messages (e.g., RRC connection reconfiguration), including the default SL DRX cycle length / SL DRX on-duration timer length / SL DRX inactivity timer length, N, M, scaling factor #1 (SF#1) for the SL DRX on-duration timer, and / or SF#2 for the SL DRX inactivity timer. In another example, a list of SF#1 and / or SF#2 may be included, and each SF#1 and / or SF#2 may be linked to the number of group member UEs; for example, a first SF#1 may be used when the number of group member UEs is (equal to or) less than a threshold #1, a second SF#1 may be used when the number of group member UEs is greater than a threshold #1 but (equal to or) less than a threshold #2, and so on.

[0120] Instead of system information or RRC-specific messages (e.g., RRC connection reconfiguration), all or a portion of SL DRX-related configurations can also be pre-configured. In T611, T612, and T613, when the UE receives SL DRX-related configurations, the UE determines whether DRX is applied to a given multicast / broadcast group that the UE is interested in sending and / or receiving. To assist the UE, the configurations in T601, T602, and T603, or this pre-configuration, may include information indicating whether SL DRX operations are applied according to the joined multicast / broadcast groups.

[0121] A simple example includes a one-bit indication based on the group ID (e.g., L1 / L2 destination ID or upper-layer link ID). It can be assumed that for the UE's group ID (e.g., L1 / L2 destination ID or upper-layer link ID), information indicating the application of SL DRX operation is pre-configured in the diagram. The UE calculates the starting subframe and time slot for the first SL DRX start duration timer. In this calculation, the UE's group ID (e.g., L1 / L2 destination ID or upper-layer link ID) is used to calculate the starting subframe and time slot to distribute different group members at different timings, which avoids resource conflicts / congestion across different groups. An example of the calculation is as follows.

[0122] In one example, the starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (L1 / L2 destination id) modulo (SL DRX period)}. In another example, the starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (L1 / L2 destination id) modulo (N)}.

[0123] In another example, the starting time slot is the time slot following {(L1 / L2 destination id) modulo M} from the starting subframe determined above.

[0124] Note that instead of the L1 / L2 destination ID, the upper-layer link / application ID or any kind of ID that can distinguish between packetcast / broadcast groups can be used in the above calculations. Note that it is also possible to calculate the starting subframe simply by using the L1 / L2 destination ID in the modulo equation, but the starting timeslot is fixed and there is no calculation as shown in the example above (e.g., the starting timeslot can be fixed as the first timeslot in the starting subframe).

[0125] If the UE knows the number of group members, it can also calculate the actual SL DRX enable duration timer length and / or SL DRX inactivity timer length for a given group, indicated by the L1 / L2 destination ID or upper-layer link ID. For example: the SL DRX enable duration timer is {(number of group members) * SF#1}; and / or the SL DRX inactivity timer is {(number of group members) * SF#2}. In another example, the SL DRX enable duration timer is {(received SL DRX enable duration timer length) * (SF#1 corresponding to the number of group members)}; and / or the SL DRX inactivity timer is {(received SL DRX inactivity timer length) * (SF#2 corresponding to the number of group members)}.

[0126] If the UE does not know the number of group members, the default SL DRX enable duration timer length and SL DRX inactivity timer length are used. Note that this embodiment also includes the possibility that the default SL DRX enable duration timer length and SL DRX inactivity timer length can be used normally regardless of whether the UE knows the number of group members. Furthermore, it is noted in the figure that it is assumed that separate SF values ​​can be signaled for the SL DRX enable duration timer and SL DRX inactivity timer; however, a single common SF can also be used instead of two separate SFs.

[0127] like Figure 9 As shown, T631 and T641 indicate the calculated start subframe and time slot timing, and the SL DRX start duration timer starts from T631 in RX UE and from T641 in TX UE#1 and TX UE#2. Note that T631 and T641 are likely to be the same timing. From the perspective of the TX UE, TX UE#1 and TX UE#2 need to start resource (re)selection in advance before the actual PSCCH and / or PSSCH transmission. Resource (re)selection can be performed based on channel sensing (including partial sensing) or random selection. The details of the resource (re)selection process are specified in 3GPP standard specifications (e.g., physical layer control procedures and physical layer data procedures).

[0128] It can be assumed that TX UE#1 and TX UE#2 perform resource (re)selection in T621 and T622. In T621 and T622, if the SL inactivity timer is running, the TX UE can select resources for initial transmission (i.e., excluding HARQ retransmissions) during the period from T641 to T644 (i.e., when the SL DRX start duration timer is running) or during the period from T632 to T635 (i.e., when the SL DRX inactivity timer is running). To ensure that the TX UE selects resources for transmission during the period when the SL DRX start duration / inactivity timer is running in (multiple) peer RX UEs, the TX UE needs to consider the resource selection window that also begins when the SL DRX start duration timer starts.

[0129] For example, refer to Figure 8 TX UE can assume that the start time of the resource selection window (n+T1) is equal to the start time of the SL DRX start duration timer (e.g., Figure 6 (T641 and T646 in the example), and the time before the SL DRX starts the duration timer (e.g., Figure 6 In this case, the sensing window's position in the time domain is determined based on the assumption that the resource selection window begins at the start time of the SL DRX enable duration timer. Using the same principle, the end time of the resource selection window (n+T2) is equal to the expiration of the SL DRX inactivity timer and the runtime of any SL DRX timer (e.g., the SL DRX HARQ retransmission timer, etc.) where no defined duration for which (multiple) RX UEs need to listen to the PSCCH and / or PSSCH is specified.

[0130] exist Figure 9 In this example, TX UE#1 sends PSCCH and PSSCH for the initial transmission in T642, and TX UE#2 sends PSCCH and PSSCH for the initial transmission in T643, while the SL DRX starts a duration timer. Whenever the RX UE receives the PSCCH and / or PSSCH for the initial transmission of a mapped or interested multicast / broadcast group ID (e.g., a mapped or interested L1 / L2 destination ID or upper-layer link ID), the RX UE starts or restarts (if the timer has already been started and is running) the SL DRX inactivity timer, as described in T632 and T633.

[0131] exist Figure 9In the process, the SL DRX inactivity timer, restarted from T633, expires at T635 because there are no further PSCCH and / or PSSCH for the initial transmission from any TX UE. On the TX UE side, the SL DRX inactivity timer is maintained in a similar manner to the RX UE. For example, when TX UE#1 sends its own PSCCH and / or PSSCH for the initial transmission to the RX UE, TX UE#1 starts the SL DRX inactivity timer at T642, and once the transmission is complete at T642, the UE becomes an RX UE, assuming no further data needs to be sent. This means that the UE can receive the PSCCH and / or PSSCH for the initial transmission from TX UE#1 at T633 as an RX UE.

[0132] Then, the UE restarts the SL DRX inactivity timer at T643, and the SL DRX inactivity timer expires at T645. For example, TX UE#2, acting as the RX UE, starts the SL DRX inactivity timer at T632. Because TX UE#2 does not perform transmissions at that time, the RX UE receives the PSCCH and / or PSSCH for the initial transmission from TX UE#1 at T632. And when TX UE#1 sends its own PSCCH and / or PSSCH for the initial transmission to the RX UE at T643, TX UE#1 restarts the SL DRX inactivity timer at T643 (because the timer has already been started and is running), and the SL DRX inactivity timer expires at T645.

[0133] Using this specified rule, the start timing and expiration timing of the SL DRX inactivity timer are synchronized between (multiple) RX UEs and (multiple) TX UEs. Note that the SL DRX enable duration timer is also maintained in the TX UE in a similar manner to the RX UE, so the actual start subframe and time slot of the SL DRX enable duration timer (T631 in the RX UE and T641 in the TX UE) and the expiration timing of the SL DRX enable duration timer (T634 in the RX UE and T644 in the TX UE) are synchronized between (multiple) TX UEs and (multiple) RX UEs.

[0134] In DRX operation for a given L1 / L2 destination ID of interest / mapping, while the SL DRX Enable Duration Timer and SL DRX Inactivity Timer are running (from T631 to T635), (multiple) RX UEs listen for the PSCCH and / or PSSCH for initial transmission (not for HARQ retransmission). Otherwise, for a given L1 / L2 destination ID of interest / mapping, (multiple) RX UEs skip listening for the PSCCH and / or PSSCH for initial transmission unless other DRX active times specified in the 3GPP standard specification (e.g., MAC) are met (besides the SL DRX Enable Duration Timer and SL DRX Inactivity Timer, such as the duration for which the SL DRX HARQ retransmission timer runs). After T635, (multiple) RX UEs start the next SL DRX Enable Duration Timer at T636, after the SL DRX cycle length from T631. In the same manner, (multiple) TX UEs start the next SL DRX Enable Duration Timer at T646. The SL DRX cycle length can be derived using the following example.

[0135] In one example, the default SL DRX cycle lengths for T601, T602, and T603 are used.

[0136] In another example, the default SL DRX cycle lengths for T601, T602, and T603 are initially used. However, if the SL DRX cycle length is shorter or longer than the default SL DRX cycle length, it can be updated based on the minimum of {the elapsed time of PSCCH and / or PSSCH reception since the start time of the SL DRX start duration timer and the resource reservation period in the SCI of the PSCCH and / or PSSCH}. For example, it can be assumed that the default SL DRX cycle is 320ms in T603, the resource reservation period information #1 included in the SCI of the PSCCH and / or PSSCH of T632 indicates 70ms and (T632-T631) is 10ms, and the resource reservation period information #2 included in the SCI of the PSCCH and / or PSSCH of T633 indicates 140ms and (T633-T631) is 20ms. 80ms is derived from the minimum of {(70+10)ms, (140+20)ms}, and since 80ms is shorter than the default SL DRX cycle length (320ms), 80ms is determined to be the SL DRX cycle length.

[0137] Note that the functional concepts / definitions for the SL DRX enable duration timer are referenced to the SL DRX inactivity timer, SL DRX period and SL DRX HARQ retransmission timer, drx-onDurationTimer, drx-InactivityTimer, DRX period and drx-RetransmissionTimerDL defined for downlink in 3GPP standard specifications (e.g., MAC).

[0138] Figure 10A A flowchart of a method 1000 for RX UE behavior according to an embodiment of the present disclosure is shown. Figure 10A The embodiments of method 1000 shown are for illustrative purposes only. Figure 10A One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0139] Figure 10B A flowchart of a method 1050 for RX UE behavior according to an embodiment of the present disclosure is shown. Figure 10B The embodiments of method 1050 shown are for illustrative purposes only. Figure 10B One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0140] like Figure 10A and Figure 10B As shown, in step 1001, the UE receives SL DRX related parameters / configurations via system information, RRC-specific messages (e.g., RRC connection reconfiguration), or pre-configuration, and the UE is configured by the upper layer for SL reception. The SL DRX related parameters / configurations include the default SL DRX period length, the default SL DRX on duration timer length, the default SL DRX inactivity timer length, N, M, SF#1, and SF#2. In another example, a list of SF#1 and / or SF#2 may be included, and each SF#1 and / or SF#2 may be linked to the number of group member UEs; for example, a first SF#1 is used when the number of group member UEs is (equal to or) less than threshold #1, a second SF#1 is used when the number of group member UEs is greater than threshold #1 but (equal to or) less than threshold #2, and so on. For a given L1 / L2 destination ID or upper-layer link / application ID that the UE is interested in for SL reception, in step 1011, the UE determines whether to apply SL DRX operation.

[0141] Note that the corresponding L2 destination ID for SL multicast / broadcast is provided by the upper layer and is received as part of the MAC header in the PSSCH. The L1 destination ID is provided by the MAC layer to the physical layer and is received as part of the SCI in the PSCCH and / or PSSCH. The pre-configuration includes information indicating whether SL DRX is applied for a given L2 destination ID or upper layer / application ID. Based on the pre-configuration, if SL DRX operation is applied to a given L1 / L2 destination ID or upper layer link / application ID of interest, then in step 1021, the UE calculates the starting subframe and time slot for the SL DRX activation duration timer.

[0142] The starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (multicast / broadcast id) modulo (SLDRX period)}. In another example, the starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (L1 / L2 destination id) modulo (N)}. The starting timeslot is the timeslot following {(multicast / broadcast id) modulo M} from the starting subframe. Note that the UE may also calculate the starting subframe simply by using the L1 / L2 destination id in the modulo equation (as above), and the starting timeslot is fixed and does not need to be calculated. For example, the starting timeslot can be fixed as the first timeslot in the starting subframe. Based on the pre-configuration, if the SL DRX operation is not applied to a given L1 / L2 destination ID or upper-layer link / application ID of interest, then in step 1023, the UE does not apply the SL DRX operation in SL reception for the L1 / L2 destination ID (i.e., applies Rel-16 SL reception behavior for the L1 / L2 destination ID).

[0143] If the UE knows the number of participating members belonging to the L1 / L2 destination ID in step 1031, then in step 1041, the UE calculates the SL DRX enable duration timer length and the SL DRX inactivity timer length. For example, the SL DRX enable duration timer is {(number of group members) * SF#1}, and the SL DRX inactivity timer is {(number of group members) * SF#2}. In another example, the SL DRX enable duration timer is {(received SL DRX enable duration timer length) * (SF#1 corresponding to the number of group members)}; and / or the SL DRX inactivity timer is {(received SL DRX inactivity timer length) * (SF#2 corresponding to the number of group members)}. If the UE does not know the number of participating group members, then in step 1045, the default SL DRX enable duration timer length and SL DRX inactivity timer length are used.

[0144] Note that this embodiment also includes the possibility of using the default SL DRX enable duration timer length and SLDRX inactivity timer length regardless of whether the UE knows the number of group members. Furthermore, in Figure 10A and Figure 10B It is noted that, assuming that separate SF values ​​can be signaled for the SL DRX enable duration timer and the SL DRX inactivity timer, a single common SF can also be used instead of two separate SFs.

[0145] In step 1043, the UE starts the SL DRX enable duration timer in the frame and time slot calculated in step 1021 or after the SL DRX cycle ends in step 1071, and (re)starts the SL DRX cycle at the start of the SL DRX enable duration timer. If the SL DRX enable duration timer or the SL DRX inactivity timer is running in step 1051, then in step 1053, the UE listens to the PSCCH and / or PSSCH of the L1 / L2 destination ID. If neither the SL DRX enable duration timer nor the SL DRX inactivity timer is running in step 1051, then the UE skips listening to the PSCCH and / or PSSCH until the SL DRX cycle ends / expires, unless other active times specified in the 3GPP standard specification are met (in addition to the SL DRX enable duration timer and the SL DRX inactivity timer, such as the duration for which the SL DRX HARQ retransmission timer runs) (in step 1055).

[0146] If, in step 1061, the UE receives a PSCCH and / or PSSCH with an L1 / L2 destination ID for initial transmission (not for HARQ retransmission), then in step 1063, the UE (re)starts the SL DRX inactivity timer (if the SL DRX inactivity timer has already been started and is running, it is restarted). If the SL DRX period length is shorter or longer than the default SL DRX period length, the UE may also update the SL DRX period length based on the minimum of {the elapsed time since the start time of the SL DRX start duration timer and the resource reservation period in the SCI of the PSCCH and / or PSSCH} (in step 1063). If the SL DRX period length is equal to the default DRX period length, or if no SCI with a resource reservation period is received in the PSCCH and / or PSSCH for the L1 / L2 destination ID, the UE uses the default SL DRX period length.

[0147] As another example, regardless of the PSCCH and / or PSSCH reception time and the resource retention period in the SCI of the PSCCH and / or PSSCH, the UE can use the default SL DRX period length. In this case, system information / RRC-specific messages (e.g., RRC connection reconfiguration) / pre-configuration can include multiple default SL DRX periods based on the QoS level, and in this case, the UE can select the most appropriate default SL DRX period based on the required QoS level for SL communication with L1 / L2 destination IDs. If the SL DRX period ends / expires in step 1071, the UE proceeds to step 1031. If the SL DRX period does not end or expire, the UE proceeds to step 1051. In step 1061, if the UE does not receive the PSCCH and / or PSSCH with L1 / L2 destination IDs for the initial transmission, the UE proceeds to step 1071.

[0148] Figure 11A A flowchart of a method 1100 for TX UE behavior according to an embodiment of the present disclosure is shown. Figure 11A The embodiments of method 1100 shown are for illustrative purposes only. Figure 11A One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0149] Figure 11B A flowchart of a method 1150 for TX UE behavior according to an embodiment of the present disclosure is shown. Figure 11B The embodiments of method 11500 shown are for illustrative purposes only. Figure 11B One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0150] like Figure 11A and Figure 11BAs shown, in step 1101, the UE receives SL DRX related parameters / configurations via system information, RRC-specific messages (e.g., RRC connection reconfiguration), or pre-configuration, and the UE is configured by the upper layer for SL transmission. The SL DRX related parameters / configurations include the default SL DRX cycle length, the default SL DRX on duration timer length, the default SL DRX inactivity timer length, N, M, SF#1, and SF#2. In another example, a list of SF#1 and / or SF#2 may be included, and each SF#1 and / or SF#2 may be linked to the number of group member UEs; for example, a first SF#1 may be used when the number of group member UEs is (equal to or) less than a threshold #1, a second SF#1 may be used when the number of group member UEs is greater than a threshold #1 but (equal to or) less than a threshold #2, and so on.

[0151] For a given L1 / L2 destination ID or upper-layer link / application ID that the UE is interested in sending to SL, in step 1111, the UE determines whether to apply DRX operation.

[0152] Note that the corresponding L2 destination ID for SL multicast / broadcast is provided by the upper layer and is sent / received as part of the MAC header in the PSSCH. The L1 destination ID is provided by the MAC layer to the physical layer and is sent / received as part of the SCI in the PSCCH and / or PSSCH. Pre-configuration includes information indicating whether SL DRX is applied for a given L2 destination ID or upper layer / application ID.

[0153] Based on the pre-configuration, if the SL DRX operation is applied to a given L1 / L2 destination ID or upper-layer link / application ID of interest, then in step 1121, the UE calculates the starting subframe and time slot for the SL DRX start duration timer. The starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (multicast / broadcast ID) modulo (SL DRX period)}. In another example, the starting subframe is an incoming subframe that satisfies {[(SFN*10)+subframe number] modulo (SL DRX period) = (L1 / L2 destination ID) modulo (N)}. The starting time slot is the time slot following {(multicast / broadcast ID) modulo M} from the starting subframe.

[0154] Note that the UE may also calculate the starting subframe simply by using the L1 / L2 destination ID in the modulo equation (as above), and the starting timeslot is fixed and does not need to be calculated. For example, the starting timeslot may be fixed as the first timeslot in the starting subframe. Based on the pre-configuration, if the SL DRX operation is not applied to SL communication with a given L1 / L2 destination ID or upper-layer link / application ID of interest, then in step 1123, the UE does not apply the SLDRX operation for the L1 / L2 destination ID in SL transmission (i.e., applies Rel-16 SL transmission behavior for the L1 / L2 destination ID).

[0155] If the UE knows the number of participating members belonging to the L1 / L2 destination ID in step 1131, then in step 1141, the UE calculates the SL DRX enable duration timer length and the SL DRX inactivity timer length. For example, the SL DRX enable duration timer is {(number of group members) * SF#1}, and the SL DRX inactivity timer is {(number of group members) * SF#2}. In another example, the SL DRX enable duration timer is {(received SL DRX enable duration timer length) * (SF#1 corresponding to the number of group members)}; and / or the SL DRX inactivity timer is {(received SL DRX inactivity timer length) * (SF#2 corresponding to the number of group members)}. If the UE does not know the number of participating group members, then in step 1147, the default SL DRX enable duration timer length and SL DRX inactivity timer length are used.

[0156] Note that this embodiment also includes the possibility that the default SL DRX enable duration timer length and SL DRX inactivity timer length can be used regardless of whether the UE knows the number of group members. Furthermore, it is noted in the figure that while it is assumed that separate SF values ​​can be signaled for the SL DRX enable duration timer and SL DRX inactivity timer, a single common SF can also be used instead of two separate SFs. In step 1143, the UE performs resource selection in advance before the PSCCH and / or PSSCH are transmitted.

[0157] For resources used for initial transmission (not for HARQ retransmission), the UE selects resources during the period when the SL DRX enable duration timer is running or the SL DRX inactivity timer is running. Note that resource selection is based on channel sensing (including partial sensing) performed during a previous window or random selection period as specified in the 3GPP standard specification.

[0158] In step 1145, the UE starts an SL DRX enable duration timer in the frame and time slot calculated in step 1121 or after the DRX cycle ends / expires in step 1171, and (re)starts the SL DRX cycle at the start of the SL DRX enable duration timer. If the SL DRX enable duration timer or the SL DRX inactivity timer is running in step 1151, then in step 1153, the UE listens for the PSCCH and / or PSSCH of the L1 / L2 destination ID, sends the PSCCH and / or PSSCH when the resource selected in step 1143 is available, and performs another resource selection and PSCCH and / or PSSCH transmission if necessary (e.g., if the UE has more new data to transmit in the transmit buffer).

[0159] The UE can select resources for initial transmission during the period when the SL enable duration timer or the SL inactive timer is running. If neither the SL enable duration timer nor the SL inactive timer is running in step 1151, the UE does not perform resource selection and does not send PSCCH and PSSCH for initial transmission until the end / expiration of the DRX cycle, unless other active times specified in the 3GPP standard specification are met (other than the SL DRX enable duration timer and the SL DRX inactive timer, such as the duration during which the SL DRX HARQ retransmission timer is running) (in step 1155). If, in step 1161, the UE sends or receives a PSCCH and / or PSSCH with L1 / L2 destination IDs for initial transmission (not for HARQ retransmission), the UE (re)starts the SL DRX inactivity timer (if the SL DRX inactivity timer has already been started and is running, then restarts it), and if the SL DRX period length is shorter or longer than the default SL DRX period length, the UE can also update the SL DRX period length based on the minimum of {the time elapsed since the start time of the SL DRX start duration timer for sending / receiving PSCCH and / or PSSCH and the resource reservation period in the SCI of the PSCCH and / or PSSCH} (in step 1163).

[0160] If the SL DRX period length is equal to the default SL DRX period length, or if no SCI is received in the PSCCH and / or PSSCH with a resource reservation period for the L1 / L2 destination ID, the UE uses the default SL DRX period length. As another example, the UE can use the default SL DRX period length regardless of the PSCCH and / or PSSCH reception time and the resource reservation period in the PSCCH. In this case, system information / RRC-specific messages (e.g., RRC connection reconfiguration) / preconfiguration can include multiple default SL DRX periods based on the QoS level, and the UE can select the most appropriate default SL DRX period based on the required QoS level for the L1 / L2 destination ID.

[0161] Note that in steps 1161 and 1163, the difference compared to the RX UE behavior is that the TX UE includes not only the received PSCCH and / or PSSCH, but also its own transmitted PSCCH and / or PSSCH. For example, the SL DRX inactivity timer is also (re)started when the TX UE transmits the PSCCH and / or PSSCH for the initial transmission, and the elapsed time of its own PSCCH transmission and the resource reservation period in the SCI of the PSCCH and / or PSSCH are also taken into account in the update of the SL DRX cycle length.

[0162] If the SL DRX cycle ends / expires in step 1171, the UE proceeds to step 1131. If the SL DRX cycle does not end or expire, the UE proceeds to step 1151. In step 1161, if the UE does not receive the PSCCH and / or PSSCH with L1 / L2 destination IDs for initial transmission, the UE proceeds to step 1171. Figure 11A and Figure 11B As shown, it can be assumed that the TX UE also maintains the same timers as the SL DRX enable duration timer and SL DRX inactivity timer on the RX UE side. However, it is also possible that the TX UE maintains timers similar to those on the RX UE side. Figure 11A and Figure 11B The SL DRX Enable Duration Timer and the SLDRX Inactive Timer shown are new timers (with different names) that operate in the same or similar manner.

[0163] As described in the foregoing embodiments and / or examples, it is assumed that for a given source ID (L1 / L2 source TX UE ID), or destination ID (L1 / L2 destination RX UE / group ID), or a combination of source ID and destination ID, or a combination of SL logical channel ID, source ID, and destination ID, the DRX of the RX UE and / or the corresponding DTX of the TX UE operate according to (multiple) SL links.

[0164] This means that if the source ID (L1 / L2 source ID), or the destination ID (L1 / L2 destination ID), or the combination of source ID and destination ID, or the SL logical channel ID, or the combination of source ID and destination ID are different, then different DRXs can operate on (multiple) SL links.

[0165] In another example, the DRX of the RX UE and / or the corresponding DTX of the TX UE can operate differently depending on the SL propagation type. For example, if the SL link is SL unicast, then for a given source ID, the DRX of the RX UE and / or the corresponding DTX of the TX UE operate according to (multiple) SL links, while if the SL link is SL multicast or broadcast, then for a given destination ID, the DRX of the RX UE and / or the corresponding DTX of the TX UE operate according to (multiple) SL links. This is because, in general, DRX operation is highly dependent on the service pattern generated in the TX UE, so it makes sense for DRX to operate according to the source TX UE. This principle works well for SL unicast; however, for SL multicast / broadcast, considering that many UEs can be TX UEs (e.g., group members), maintaining this principle for SL multicast / broadcast could lead to more UE power consumption issues due to numerous independent activity times.

[0166] Since all member UEs share the same application and most likely similar service patterns (or QoS levels) in multicast / broadcast with the same destination ID, it is more desirable for DRX to operate according to the destination ID in SL multicast / broadcast. Note that if the SL link is SL unicast, the DRX in the RX UE (and / or the corresponding DTX in the TX UE) operates according to the SL link(s) with a given source ID, and if the SL link is SL multicast / broadcast, the DRX (and / or DTX) operates according to the SL link(s) with a given destination ID; any other combination is also possible in this embodiment.

[0167] Figure 12 A flowchart of a method 1200 for discontinuous reception of sidelink multicast / broadcast operations according to an embodiment of the present disclosure is shown. Method 1200 can be performed by a UE (e.g., such as...) Figure 1 Execute as shown in 111-116). Figure 12 The embodiments of method 1200 shown are for illustrative purposes only. Figure 12 One or more of the components shown may be implemented in a dedicated circuit configured to perform the indicated function, or one or more of the components may be implemented by one or more processors that execute instructions to perform the indicated function.

[0168] like Figure 12 As shown, method 1200 begins at step 1202. In step 1202, the first UE determines whether to initiate an SL DRX operation for SL multicast / broadcast operation.

[0169] In step 1204, the first UE identifies at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer for SL multicast / broadcast operations.

[0170] In step 1206, the first UE identifies a time instance of the start of the SLDRX cycle based on at least one of the destination ID and the SL DRX start offset. In step 1206, the time instance includes at least one of a time slot, a subframe, and a frame.

[0171] In step 1208, the first UE receives PSCCH and PSSCH from the second UE belonging to the destination ID based on at least one of SL DRX cycle length, SL DRX start offset, destination ID and SL DRX timer.

[0172] In one embodiment, the first UE identifies an indicator configured according to the L2 destination identifier ID included in the pre-configuration information for SL communication, which indicates whether to initiate an SL DRX operation for SL multicast / broadcast operations.

[0173] In one embodiment, the first UE identifies at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer for SL multicast / broadcast operations based on pre-configuration information.

[0174] In one embodiment, the first UE further identifies at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer for SL multicast / broadcast operations based on at least one of SIB or dedicated RRC signaling.

[0175] In one embodiment, the first UE determines, based on the characteristics of data transmission, whether a default value is applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer respectively; based on the determination that a default value is applied, the first UE applies a default value to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer respectively; and based on the determination that no default value is applied, the first value is applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer respectively, wherein the default value and the first value are different from each other.

[0176] In one embodiment, the first UE determines whether its upper layer has identified the number of group member UEs, and adjusts at least one of a plurality of scaling factors to the value of the SL DRX timer based on the number of group member UEs. In such an embodiment, the SL DRX timer is at least one of an SL DRX on duration timer and an SL DRX inactivity timer. In such an embodiment, the plurality of scaling factors corresponding to the number of group member UEs are configured based on at least one of pre-configuration information, SIB, dedicated RRC signaling, or predetermined values.

[0177] In one embodiment, the first UE receives an SCI or MAC CE, the SCI or MAC CE including an indicator indicating whether an SL DRX operation is applied for an SL multicast / broadcast operation with a destination ID.

[0178] The flowcharts above illustrate example methods that can be implemented according to the principles of this disclosure, and various changes can be made to the methods shown in the flowcharts herein. For example, although shown as a series of steps, the individual steps in each diagram may overlap, occur in parallel, occur in different orders, or occur multiple times. In another example, steps may be omitted or replaced by other steps.

[0179] Although this disclosure has been described with reference to exemplary embodiments, various changes and modifications will occur to those skilled in the art. This disclosure is intended to cover such changes and modifications that fall within the scope of the appended claims. None of the descriptions in this application should be construed as implying that any particular element, step, or function is an essential element that must be included within the scope of the claims. The scope of the patent subject matter is defined by the claims.

Claims

1. A first user equipment (UE), comprising: The processor is configured as follows: Identification Layer 2 (L2) Destination Identifier ID Determine whether to initiate a sidelink discontinuous SLDRX operation for sidelink SL multicast / broadcast transmission, and Determine the SL DRX start offset based on the L2 destination ID, and A transceiver, operably connected to the processor, is configured to receive the Physical Side Link Control Channel (PSCCH) and the Physical Side Link Shared Channel (PSSCH) from a second UE associated with an L2 destination ID, based on the SL DRX start offset.

2. The first UE according to claim 1, wherein, The processor is also configured to determine whether to initiate an SL DRX operation for SL multicast / broadcast transmission based on the L2 destination ID and information included in the pre-configuration information, wherein the information indicates whether to apply SL DRX for SL multicast or broadcast transmission.

3. The first UE according to claim 1, wherein, The processor is also configured to: Based on pre-configuration information, identify at least one of the SL DRX period length, SL DRX start offset, and SLDRX timer used for SL multicast / broadcast transmission; or Based on at least one of System Information Block (SIB) or Dedicated Radio Resource Control (RRC) signaling, identify at least one of the following for SL multicast / broadcast transmission: SL DRX period length, SL DRX start offset, and SL DRX timer.

4. The first UE according to claim 1, wherein, The processor is also configured to: Based on the characteristics of data transmission, determine whether to apply default values ​​to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; Based on the determination that default values ​​were applied, default values ​​were applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; and Based on the determination that no default value is applied, a first value is applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer, wherein the default value and the first value are different from each other.

5. The first UE according to claim 1, in, The processor is also configured to: Determine whether the upper layer of the first UE has identified the number of member UEs in the group, and Based on the number of member UEs in the group, at least one of the values ​​of the SL DRX timer is adjusted using multiple scaling factors. The transceiver is further configured to receive sidelink control information (SCI) or MAC control element (CE) including an indicator that indicates whether SL DRX operation is applied for SL multicast / broadcast transmissions with L2 destination IDs. The SL DRX timer is at least one of an SL DRX enable duration timer and an SL DRX inactivity timer. The multiple scaling factors corresponding to the number of group member UEs are configured based on at least one of pre-configuration information, SIB, dedicated RRC signaling, or predetermined values.

6. A method performed by a first user equipment (UE), the method comprising: Identify Layer 2 (L2) Destination Identifier ID; Determine whether to initiate a sidelink discontinuous SL DRX operation for sidelink SL multicast / broadcast transmission; as well as Determine the starting offset of SL DRX based on L2 destination ID; as well as Based on the SL DRX start offset, the Physical Side Link Control Channel (PSCCH) and Physical Side Link Shared Channel (PSSCH) are received from the second UE associated with the L2 destination ID.

7. The method of claim 6, wherein the determination further comprises determining whether to initiate an SL DRX operation for SL multicast / broadcast transmission based on the L2 destination ID and information included in the pre-configuration information, and in, The information indicates whether SL DRX is applied for SL multicast or broadcast transmission.

8. The method according to claim 6, further comprising: Based on pre-configuration information, identify at least one of the SL DRX period length, SL DRX start offset, and SLDRX timer used for SL multicast / broadcast transmission; or Based on at least one of System Information Block (SIB) or Dedicated Radio Resource Control (RRC) signaling, identify at least one of the following for SL multicast / broadcast transmission: SL DRX period length, SL DRX start offset, and SL DRX timer.

9. The method according to claim 6, further comprising: Based on the characteristics of data transmission, determine whether to apply default values ​​to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; Based on the determination that default values ​​were applied, default values ​​were applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; and Based on the determination that no default value is applied, a first value is applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer, wherein the default value and the first value are different from each other.

10. The method of claim 6, further comprising: Determine whether the upper layer of the first UE has identified the number of group member UEs; Based on the number of member UEs, at least one of the values ​​of the SL DRX timer is adjusted using multiple scaling factors; and Receive sidelink control information (SCI) or MAC control element (CE) including indicators, which indicate whether SL DRX operation should be applied for SL multicast / broadcast transmissions with L2 destination IDs. The SL DRX timer is at least one of an SL DRX enable duration timer and an SL DRX inactivity timer. The multiple scaling factors corresponding to the number of group member UEs are configured based on at least one of pre-configuration information, SIB, dedicated RRC signaling, or predetermined values.

11. A second user equipment (UE), comprising: The processor is configured as follows: Identification Layer 2 (L2) Destination Identifier ID Determine whether to initiate a sidelink discontinuous SLDRX operation for sidelink SL multicast / broadcast transmission, and Determine the SL DRX start offset based on the L2 destination ID, and A transceiver, operably connected to the processor, is configured to transmit the Physical Side Link Control Channel (PSCCH) and the Physical Side Link Shared Channel (PSSCH) to a first UE associated with an L2 Destination ID based on the SL DRX start offset.

12. The second UE according to claim 11, wherein, The processor is also configured to determine whether to initiate an SL DRX operation for SL multicast / broadcast transmission based on the L2 destination ID and information included in the pre-configuration information, and The information indicates whether SL DRX is applied for SL multicast or broadcast transmission.

13. The second UE according to claim 11, wherein, The processor is also configured to: Based on pre-configuration information, identify at least one of the SL DRX period length, SL DRX start offset, and SLDRX timer used for SL multicast / broadcast transmission; or Based on at least one of System Information Block (SIB) or Dedicated Radio Resource Control (RRC) signaling, identify at least one of the following for SL multicast / broadcast transmission: SL DRX period length, SL DRX start offset, and SL DRX timer.

14. The second UE according to claim 11, wherein, The processor is also configured to: Based on the characteristics of data transmission, determine whether to apply default values ​​to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; Based on the determination that default values ​​were applied, default values ​​were applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer; and Based on the determination that no default value is applied, a first value is applied to at least one of the SL DRX cycle length, SL DRX start offset, and SL DRX timer, respectively, where the default value and the first value are different from each other.

15. The second UE according to claim 11, in, The processor is also configured to: Determine whether the upper layer of the first UE has identified the number of member UEs in the group, and Based on the number of member UEs in the group, at least one of the values ​​of the SL DRX timer is adjusted using multiple scaling factors. The transceiver is further configured to receive sidelink control information (SCI) or MAC control element (CE) including an indicator that indicates whether SL DRX operation is applied for SL multicast / broadcast transmissions with L2 destination IDs. The SL DRX timer is at least one of an SL DRX enable duration timer and an SL DRX inactivity timer. The multiple scaling factors corresponding to the number of group member UEs are configured based on at least one of pre-configuration information, SIB, dedicated RRC signaling, or predetermined values.

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