Improving power efficiency by using sidelink wake-up signal

Abstract

Certain aspects of the present disclosure relate to wireless communication and, more particularly, to techniques for sidelink (SL) power saving using SL wake-up signal (WUS). A method that can be performed by a user equipment (UE) includes determining, based on a WUS resource configuration, a resource for a SL WUS transmission from a second UE; monitoring the resource for a SL WUS from the second UE; and participating in a SL communication with the second UE if the SL WUS is detected during the monitoring.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Application No. 17 / 166,997, filed on February 3, 2021, the entire contents of which are expressly incorporated herein by reference, as fully set forth below, and for all applicable purposes. Technical Field

[0003] Various aspects of this disclosure relate to wireless communication, and more specifically, to techniques for SL power saving using side link (SL) wake-up signals (WUS). Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. These wireless communication systems can employ multiple access technologies that enable communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access systems include the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) system, the improved LTE (LTE-A) system, Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems.

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the city, country, region, and even global levels. New radios (e.g., 5G NR) are examples of emerging telecommunications standards. NR is a set of enhancements to the Long Term Evolution (LTE) mobile standard released by 3GPP. NR is designed to better support mobile broadband internet access by improving spectrum efficiency, reducing costs, improving service, utilizing new spectrum, and using OFDMA with a cyclic prefix (CP) on the downlink (DL) and uplink (UL). For this purpose, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

[0006] However, with the continued growth in demand for mobile broadband access, there is a need for further improvements to NR and LTE technologies. Preferably, these improvements should be applicable to other multiple access technologies and telecommunications standards that employ these technologies. Summary of the Invention

[0007] The systems, methods, and apparatuses of this disclosure have several aspects, none of which are solely responsible for their desired properties. Upon consideration of this discussion, and especially after reading the section entitled "Detailed Description," those skilled in the art will understand how the features of this disclosure provide advantages including improved side link (SL) power consumption.

[0008] One or more aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication by a first user equipment (UE). The method generally includes determining resources for side-link (SL) WUS transmissions from a second UE based on wake-up signal (WUS) resource configuration; monitoring resources for SL WUS from the second UE; and engaging in SL communication with the second UE if SL WUS is detected during monitoring.

[0009] One or more aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication by a second UE. The method generally includes determining, based on WUS resource configuration, resources for SL WUS transmission to the second UE; transmitting the SL WUS to the second UE on the determined resources; and engaging in SL communication with the second UE after transmitting the SL WUS.

[0010] One or more aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication by a first UE. The apparatus generally includes at least one processor and memory coupled to the at least one processor. The memory generally includes code executable by the at least one processor to cause the first UE to: determine resources for SL WUS transmissions from a second UE based on WUS resource configuration; monitor resources for SL WUS transmissions from the second UE; and, if SL WUS is detected during monitoring, engage in SL communication with the second UE.

[0011] One or more aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication by a second UE. The apparatus generally includes at least one processor and memory coupled to the at least one processor. The memory generally includes code executable by the at least one processor to cause the second UE to: determine, based on WUS resource configuration, resources for SL WUS transmission to the second UE; transmit SL WUS to the second UE on the determined resources; and engage in SL communication with the second UE after transmitting the SL WUS.

[0012] One or more aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes units for performing the following operations: determining resources for SL WUS transmissions from a second UE based on WUS resource configuration; monitoring resources for SL WUS from the second UE; and engaging in SL communication with the second UE if SL WUS is detected during monitoring.

[0013] One or more aspects of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication. The apparatus generally includes units for determining resources for SL WUS transmission to a second UE based on WUS resource configuration; units for transmitting SL WUS to the second UE on the determined resources; and units for participating in SL communication with the second UE after transmitting the SL WUS.

[0014] One or more aspects of the subject matter described in this disclosure may be implemented in a computer-readable medium having computer-executable code for wireless communication stored thereon. The computer-executable code generally includes code for performing the following operations: determining resources for SL WUS transmissions from a second UE based on WUS resource configuration; monitoring resources for SL WUS transmissions from the second UE; and engaging in SL communication with the second UE if SL WUS is detected during monitoring.

[0015] One or more aspects of the subject matter described in this disclosure may be implemented in a computer-readable medium having computer-executable code for wireless communication stored thereon. The computer-executable code generally includes code for determining, based on WUS resource configuration, resources for SL WUS transmission to the second UE; code for transmitting the SL WUS to the second UE on the determined resources; and code for participating in SL communication with the second UE after transmitting the SL WUS.

[0016] To achieve the foregoing and related objectives, one or more aspects include the features fully described below and specifically pointed out in the claims. The following description and drawings set forth certain illustrative features of one or more aspects in detail. However, these feature indications can be adopted in only a few of the various ways in which the principles of each aspect apply. Attached Figure Description

[0017] To gain a more detailed understanding of the features described above in this disclosure, the content briefly summarized above can be described in more specific terms by referring to various aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only certain aspects of this disclosure, and that the description may permit other equally valid aspects.

[0018] Figure 1 This is a block diagram conceptually illustrating certain aspects of an example telecommunications system based on this disclosure.

[0019] Figure 2 This is a block diagram conceptually illustrating the design of an example base station (BS) and user equipment (UE) according to certain aspects of this disclosure.

[0020] Figure 3 This is an example frame format for New Radio (NR) based on certain aspects of this disclosure.

[0021] Figure 4A and Figure 4B A graphical representation of an example vehicle-to-everything (V2X) system is shown, illustrating certain aspects of this disclosure.

[0022] Figure 5A and Figure 5B Two side link (SL) communication modes are shown according to certain aspects of this disclosure.

[0023] Figure 6 This is a schematic diagram illustrating an example discontinuous reception (DRX) cycle according to certain aspects of this disclosure.

[0024] Figure 7 This is a schematic diagram illustrating an example side-link (SL) wake-up signal (WUS) configuration according to certain aspects of this disclosure.

[0025] Figure 8 This is a flowchart illustrating example operations for wireless communication by a UE according to various aspects of this disclosure.

[0026] Figure 9 This is a flowchart illustrating example operations for wireless communication by a UE according to various aspects of this disclosure.

[0027] Figure 10A and Figure 10B These are call flowcharts illustrating example SL communications for one-way and two-way WUS configuration between UEs, respectively, according to certain aspects of this disclosure.

[0028] Figure 11 This is a schematic diagram illustrating an example SL WUS configuration that incorporates DRX loops according to certain aspects of this disclosure.

[0029] Figure 12A and Figure 12B Example options for configuring WUS resources are shown, based on certain aspects of this disclosure.

[0030] Figures 13A-13CThis illustrates an example time slot format when WUS resources are included in a WUS resource pool shared by multiple UEs, according to certain aspects of this disclosure.

[0031] Figure 14 This document illustrates an example subset of available WUS resources for sending and / or receiving WUS, in accordance with certain aspects of this disclosure.

[0032] Figure 15A This illustrates communication between UEs in unicast mode, according to certain aspects of this disclosure.

[0033] Figure 15B and Figure 15C Example options for selecting WUS resources during unicast communication between UEs are shown, according to certain aspects of this disclosure.

[0034] Figure 16 An example is shown in which a Physical Side Link Feedback Channel (PSFCH) can be used in an SL WUS configuration, according to certain aspects of this disclosure.

[0035] Figure 17 An example communication device is shown according to various aspects of this disclosure, which may include various components configured to perform operations using the techniques disclosed herein.

[0036] Figure 18 An example communication device is shown according to various aspects of this disclosure, which may include various components configured to perform operations using the techniques disclosed herein.

[0037] To facilitate understanding, where possible, identical reference numerals have been used to designate identical elements common to the figures. It is anticipated that elements disclosed in one aspect can be beneficially utilized in other aspects without specific description. Detailed Implementation

[0038] This disclosure provides apparatus, methods, processing systems, and computer-readable media for side link (SL) power saving using a wake-up signal (WUS) on the SL. The use of the SL WUS allows devices to remain in a low-power state for extended periods and / or return to a low-power state more quickly.

[0039] Wireless devices may include baseband processing components, radio frequency (RF) RX front-end components (e.g., referred to as a receive (RX) chain), and RF TX front-end components (e.g., referred to as a transmit (TX) chain). Power-saving configurations can allow wireless devices to power off one or more of these RF components when not in use to save power.

[0040] In some examples, power-saving techniques can be configured for SL communications. SL power-saving configurations can define the time periods during which a radio node monitors one or more physical-side line link control channels (PSCCHs) for transmissions from other remote UEs. In some examples, power-saving configurations can use SL WUS configurations.

[0041] When a UE is configured with WUS, the techniques presented herein allow radio nodes to use SL WUS to improve power efficiency. In some aspects, SL WUS can be configured on dedicated (periodic) resources in a WUS resource pool shared by multiple UEs or on a bandwidth portion / SL carrier. The actual resources used by the UE to transmit / receive WUS can be only a subset of the available WUS resources.

[0042] The following description provides examples of SL WUS resource configurations. Changes may be made to the function and arrangement of the elements discussed without departing from this disclosure. Various processes or components may be omitted, substituted, or added as appropriate in the examples. For example, the described methods may be performed in a different order than those described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into some other examples. For example, an apparatus or method may be implemented using any number of aspects set forth herein. Moreover, this disclosure is intended to cover such apparatuses or methods practiced using structures, functions, or structures and functions other than those set forth herein or different from those set forth herein. It should be understood that any aspect of the disclosure herein may be embodied by one or more elements of the claims. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily construed as preferred or advantageous over other aspects.

[0043] Typically, any number of wireless networks can be deployed in a given geographical area. Each wireless network can support a specific Radio Access Technology (RAT) and can operate on one or more frequencies. A RAT can also be referred to as a radio technology, air interface, etc. A frequency can also be referred to as a carrier, subcarrier, frequency channel, tone, subband, etc. Each frequency can support a single RAT in a given geographical area to avoid interference between wireless networks using different RATs.

[0044] The techniques described herein can be used in a variety of wireless networks and radio technologies. For clarity, although aspects may be described herein using terms commonly associated with 3G, 4G, and / or newer radio technologies (e.g., 5G NR), aspects of this disclosure can be applied to communication systems based on other generations, including subsequent technologies.

[0045] NR access can support a variety of wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth, millimeter wave (mmW) targeting high carrier frequencies, massive machine-type communication (mMTC) targeting non-backward-compatible MTC technology, and / or mission-critical services targeting ultra-reliable low-latency communication (URLLC). These services can include latency and reliability requirements. These services can also have different transmission time intervals (TTIs) to meet their respective quality of service (QoS) requirements. Furthermore, these services can coexist in the same subframe.

[0046] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc., based on frequency / wavelength. In 5G NR, the two initial operating bands have been designated as frequency range names FR1 (410MHz–7.125GHz) and FR2 (24.25GHz–52.6GHz). Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Although a portion of FR1 is greater than 6GHz, in various documents and articles, FR1 is often (interchangeably) referred to as the “sub-6GHz” band. Similar naming issues sometimes arise regarding FR2; although FR2 differs from the Extremely High Frequency (EHF) band (30GHz–300GHz) designated as a “millimeter wave” band by the International Telecommunication Union (ITU), it is often (interchangeably) referred to as the “millimeter wave” band in documents and articles.

[0047] In light of the foregoing, unless otherwise specifically stated, it should be understood that the terms "below 6 GHz" and the like (if used herein) can broadly refer to frequencies that are less than 6 GHz, within FR1, or may include mid-band frequencies. Furthermore, unless otherwise specifically stated, it should be understood that the terms "millimeter wave" and the like (if used herein) can broadly refer to frequencies that may include mid-band frequencies, within FR2, or within the EHF band.

[0048] NR also supports beamforming, and the beam direction can be dynamically configured. It also supports precoded multiple-input multiple-output (MIMO) transmission. In some examples, the MIMO configuration in the DL can support up to eight transmit antennas, with up to eight streams in multi-layer DL transmission and up to two streams per UE. In some examples, multi-layer transmission with up to two streams per UE can be supported. Aggregation of multiple cells with up to eight serving cells can be supported.

[0049] Figure 1 An example wireless communication network 100 is shown in which various aspects of this disclosure can be implemented. For example, according to some aspects, the wireless communication network 100 may include a UE 120 configured for SL communication based on SL WUS configuration, as presented herein. Figure 1 As shown, UE 120a includes an SL WUS manager 122a, UE 120b includes an SL WUS manager 122b, and BS 110a includes an SL WUS manager 112a. WUS managers 122a and 122b can be configured to perform... Figure 8 Operation 800 and Figure 9 Operation 900.

[0050] The wireless communication network 100 may be an NR system (e.g., a 5G NR network). The core network 132 may communicate via one or more interfaces with one or more base stations (BSs) 110a-z (each BS is also individually referred to herein as BS110 or collectively as BS110) and / or UEs 120a-y (each UE is also individually referred to herein as UE 120 or collectively as UE 120). BS110 may provide communication coverage for a specific geographic area (sometimes referred to as a “cell”), which may be stationary or mobile depending on the location of the mobile BS110. In some examples, BS110 may interconnect with each other and / or with one or more other BSs or network nodes (not shown) in the wireless communication network 100 using any suitable transport network through various types of backhaul interfaces (e.g., direct physical connection, wireless connection, virtual network, etc.). Figure 1 In the example shown, BS110a, 110b, and 110c can be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS110x can be a pico BS for pico cell 102x. BS110y and 110z can be femto BSs for femto cells 102y and 102z, respectively. A BS can support one or more cells. UEs 120 (e.g., 120x, 120y, etc.) can be distributed throughout the wireless communication network 100, and each UE 120 can be stationary or mobile.

[0051] The wireless communication network 100 may also include a relay station (e.g., relay station 110r) (also referred to as a repeater, etc.) that receives transmissions of data and / or other information from an upstream station (e.g., BS110a or UE 120r) and transmits transmissions of data and / or other information to a downstream station (e.g., UE 120 or BS110), or relays transmissions between UEs 120 to facilitate communication between devices.

[0052] Network controller 130 can be coupled to a group of BS110s and provide coordination and control for these BS110s. Network controller 130 can communicate with BS110s via backhaul. Network controller 130 can communicate with core network 132 (e.g., 5G core network (5GC)), which provides various network functions such as access and mobility management, session management, user plane functions, policy control functions, authentication server functions, unified data management, application functions, network exposure functions, network repository functions, network slice selection functions, etc.

[0053] Figure 2 Example components of BS110a and UE 120a are shown (e.g., in...). Figure 1 In the wireless communication network 100, they may be similar components in UE 120b, which can be used to implement various aspects of this disclosure.

[0054] At BS110a, the transmitting processor 220 can receive data from data source 212 and control information from controller / processor 240. Control information can be used for Physical Broadcast Channel (PBCH), Physical Control Format Indicator Channel (PCFICH), Physical Hybrid ARQ Indicator Channel (PHICH), Physical Downlink Control Channel (PDCCH), Group Common PDCCH (GC PDCCH), etc. Data can be used for Physical Downlink Shared Channel (PDSCH), etc. A Media Access Control (MAC)-Control Element (MAC-CE) is a MAC layer communication structure that can be used for exchanging control commands between radio nodes. For example, the BS can send a MAC CE to the UE to put the UE into Discontinuous Receive (DRX) mode to reduce the UE's power consumption. The MAC-CE can be carried in a shared channel (such as Physical Downlink Shared Channel (PDSCH), Physical Uplink Shared Channel (PUSCH), or Physical Sidelink Shared Channel (PSSCH)). MAC-CE can also be used to transmit information that facilitates communication, such as information about buffer status and available power margin.

[0055] Processor 220 can process (e.g., encode and symbol map) data and control information separately to obtain data symbols and control symbols. Transmit processor 220 can also generate reference symbols such as those for the primary synchronization signal (PSS), secondary synchronization signal (SSS), and channel state information reference signal (CSI-RS). Transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding, if applicable) on data symbols, control symbols, and / or reference symbols, and can provide output symbol streams to modulators (MODs) in transceivers 232a-232t. Each modulator can process its own output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator can further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink (DL) signal. The DL signal from the modulators in transceivers 232a-232t can be transmitted via antennas 234a-234t respectively.

[0056] At UE 120a, antennas 252a-252r can receive downlink signals from BS 110a or downlink signals from UE 120b, and can provide the received signals to demodulators (DEMODs) in transceivers 254a-254r respectively. Each demodulator can adjust (e.g., filter, amplify, downconvert, and digitize) its respective received signal to obtain an input sample. Each demodulator can further process the input sample (e.g., for OFDM, etc.) to obtain received symbols. MIMO detector 256 can obtain the received symbols from all demodulators in transceivers 254a-254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. Receiver processor 258 can process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for UE 120a to data sink 260, and provide decoded control information to controller / processor 280.

[0057] On the uplink (UL) and / or SL, at UE 120a, the transmit processor 264 can receive and process data from data source 262 (e.g., for the Physical Uplink Shared Channel (PUSCH)) and control information from controller / processor 280 (e.g., for the Physical Uplink Control Channel (PUCCH)). The transmit processor 264 can also generate reference symbols for reference signals (e.g., for sounding reference signals (SRS)). Symbols from the transmit processor 264 can be pre-encoded by the TXMIMO processor 266 (if applicable), further processed by modulators (e.g., for SC-FDM, etc.) in transceivers 254a-254r, and transmitted to BS 110a. At BS110a, the UL signal from UE 120a can be received by antenna 234, processed by the demodulator in transceivers 232a-232t, detected by MIMO detector 236 (if applicable), and further processed by receiver processor 238 to obtain decoded data and control information transmitted by UE 120a. Receiver processor 238 can provide the decoded data to data sink 239 and the decoded control information to controller / processor 240.

[0058] Memory 242 and 282 can store data and program code for BS110a and UE 120a, respectively. Scheduler 244 can schedule the UE for data transmission on DL and / or UL.

[0059] The antenna 252, processors 266, 258, 264 and / or controller / processor 280 and / or antenna 234, processors 220, 230, 238 of UE 120a can be used to perform the various techniques and methods described herein. For example, such as Figure 2 As shown, the controller / processor 280 of UE120a has an SL WUS manager 281. The SL WUS 281 can be configured to perform... Figure 8 Operation 800 and Figure 9 Operation 900.

[0060] The antenna 234, processors 220, 260, 238 and / or the controller / processor 240 with SL WUS manager 241 of BS110a can also be used to perform the various techniques and methods described herein.

[0061] NR can utilize Orthogonal Frequency Division Multiplexing (OFDM) with a cyclic prefix (CP) on both the uplink and downlink. NR can support half-duplex operation using Time Division Duplex (TDD). OFDM and Single-Carrier Frequency Division Multiplexing (SC-FDM) divide the system bandwidth into multiple orthogonal subcarriers, which are often also referred to as tones, bins, etc. Each subcarrier can be modulated using data. Modulation symbols can be transmitted in the frequency domain using OFDM and in the time domain using SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers can depend on the system bandwidth. The minimum resource allocation, called a resource block (RB), can be 12 consecutive subcarriers. The system bandwidth can also be divided into subbands. For example, a subband can cover multiple RBs. NR can support a basic subcarrier spacing (SCS) of 15 kHz, and other SCSs can be defined with respect to the basic SCS (e.g., 30 kHz, 60 kHz, 120 kHz, 240 kHz, etc.).

[0062] Figure 3 This is a schematic diagram illustrating an example of frame format 300 for NR. The transmission timeline for each of DL and UL can be divided into units of radio frames. Each radio frame can have a predetermined duration (e.g., 10 ms) and can be divided into 10 subframes (each subframe being 1 ms) indexed from 0 to 9. Each subframe can include a variable number of time slots (e.g., 1, 2, 4, 8, 16... time slots), depending on the SCS. Each time slot can include a variable number of symbol periods (e.g., 7 or 14 symbols), depending on the SCS. The symbol periods within each time slot can be assigned an index. A micro-time slot (which may be referred to as a sub-time slot structure) refers to a transmission time interval with a duration less than a time slot (e.g., 2, 3, or 4 symbols). Each symbol in a time slot can indicate the link direction for data transmission (e.g., DL, UL, or flexible), and the link direction for each subframe can be dynamically switched. The link direction can be based on the time slot format. Each time slot can include DL / UL data and DL / UL control information.

[0063] In NR, a Synchronization Signal Block (SSB) is transmitted. In some respects, the SSB can be transmitted in a burst, where each SSB in the burst corresponds to a different beam direction for UE-side beam management (e.g., including beam selection and / or beam refinement). The SSB includes the PSS, SSS, and a two-symbol PBCH. The SSB can be transmitted at a fixed time slot location (such as in...). Figure 3The symbols 0-3 shown in the diagram are transmitted in the PSS and SSS. The PSS and SSS can be used by the UE for cell search and acquisition. The PSS provides half-frame timing, and the SS provides CP length and frame timing. The PSS and SSS can provide cell identification. The PBCH carries basic system information such as downlink system bandwidth, timing information within the radio frame, SS burst set periodicity, system frame number, etc. SSBs can be organized into SS bursts to support beam scanning. Further system information (such as Residual Minimum System Information (RMSI), System Information Block (SIB), and Other System Information (OSI)) can be transmitted on the Physical Downlink Shared Channel (PDSCH) in certain subframes. For millimeter wave (mmWave), for example, using up to sixty-four different beam directions, the SSB can be transmitted up to sixty-four times. Multiple transmissions of the SSB are called SS burst sets. SSBs in an SS burst set can be transmitted in the same frequency region, while SSBs in different SS burst sets can be transmitted in different frequency regions.

[0064] In some examples, access to the air interface can be scheduled. A scheduling entity (e.g., BS110) allocates resources for communication among some or all equipment and apparatus within its service area or cell. The scheduling entity can be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, the subordinate entity utilizes the resources allocated by the scheduling entity. BS110 is not the only entity that can be used as a scheduling entity. In some examples, UE 120 can be used as a scheduling entity, and can schedule resources for one or more subordinate entities (e.g., one or more other UE 120s), and other UE 120s can utilize the resources scheduled by UE 120 for wireless communication. In some examples, UE 120 can be used as a scheduling entity in peer-to-peer (P2P) networks and / or in mesh networks. In mesh network examples, UE 120s can communicate directly with each other in addition to communicating with a scheduling entity.

[0065] In some examples, communication between UE 120 and BS110 is referred to as an access link. The access link can be provided via the Uu interface. Communication between devices can be referred to as a sidelink.

[0066] In some examples, two or more dependent entities (e.g., UE 120) can communicate with each other using sidelink signaling. Real-world applications of such sidelink communication can include public safety, proximity services, UE-to-network relay, vehicle-to-vehicle (V2V) communication, Internet of Things (IoE) communication, IoT communication, mission-critical mesh networks, and / or various other suitable applications. Typically, sidelink signaling can refer to a signal transmitted from one dependent entity (e.g., UE 120a) to another dependent entity (e.g., another UE 120) without relaying the communication through a scheduling entity (e.g., UE 120 or BS110), even if the scheduling entity can be used for scheduling and / or control purposes. In some examples, sidelink signaling can be transmitted using licensed spectrum (unlike WLANs, which can use unlicensed spectrum). An example of sidelink communication is PC5, for example, as used in V2V, LTE, and / or NR.

[0067] Various SL channels can be used for SL communication, including the Physical Side Link Discovery Channel (PSDCH), Physical Side Link Control Channel (PSCCH), Physical Side Link Shared Channel (PSSCH), and Physical Side Link Feedback Channel (PSFCH). The PSDCH can carry discovery expressions that enable near-end devices to discover each other. The PSCCH can carry control signaling, such as side-link resource configurations and other parameters for data transmission, while the PSSCH can carry data transmission. The PSFCH can carry feedback, such as CSI related to SL channel quality.

[0068] Roadside Units (RSUs) can be utilized. RSUs can be used for V2I communication. In some examples, RSUs can act as forwarding nodes to extend coverage for UEs. In some examples, RSUs can be co-located with BSs or can be independent. RSUs can have different classifications. For example, RSUs can be classified as UE-type RSUs and micro NodeB-type RSUs. Micro NodeB-type RSUs have similar functionality to macro eNBs / gNBs. Micro NodeB-type RSUs can utilize the Uu interface. UE-type RSUs can meet stringent Quality of Service (QoS) requirements by minimizing collisions and improving reliability. UE-type RSUs can use centralized resource allocation mechanisms to allow for efficient resource utilization. Critical information (e.g., traffic conditions, weather conditions, congestion statistics, sensor data, etc.) can be broadcast to UEs within the coverage area. Repeaters can rebroadcast critical information received from some UEs. UE-type RSUs can be reliable synchronization sources.

[0069] Figure 4A and Figure 4BA graphical representation of an example vehicle-to-everything (V2X) system is shown, illustrating some aspects of this disclosure. For example, in Figure 4A and Figure 4B The vehicles shown can communicate via the SL channel according to the SL WUS resource configuration, as described herein.

[0070] exist Figure 4A and Figure 4B The V2X system provided in China offers two complementary transmission modes. Figure 4A The first transmission mode, illustrated by way of example, involves direct communication between participants close to each other in a local area (e.g., also referred to as SL communication). Figure 4B The second transmission mode illustrated by way of example involves network communication over a network, which may be implemented via a Uu interface (e.g., a wireless communication interface between a radio access network (RAN) and a UE).

[0071] Reference Figure 4A A V2X system 400A (e.g., including vV2V communication) is shown as having two vehicles 402 and 404. A first transmission mode can accommodate direct communication between different participants in a given geographic location. As shown, the vehicles may have a wireless communication link 406 with individuals (vehicle-to-pedestrian (V2P)) (e.g., via a UE) through a PC5 interface. Communication between vehicles 402 and 404 can also occur via a PC5 interface 408. Similarly, communication can occur from vehicle 402 to other highway components (e.g., highway component 410) (such as traffic signals or signs (vehicle-to-infrastructure (V2I)) via a PC5 interface 412. Regarding... Figure 4A In each communication link shown, bidirectional communication can occur between elements, so each element can be both a sender and a receiver of information. The V2X system 400 can be a self-managing system implemented without assistance from network entities. Self-managing systems can achieve improved spectrum efficiency, reduced costs, and increased reliability because network service interruptions do not occur during handover operations for mobile vehicles. The V2X system can be configured to operate in licensed or unlicensed spectrum, so any vehicle equipped with the system can access public frequencies and share information. Such coordinated / public spectrum operation takes into account safe and reliable operation.

[0072] Figure 4BA V2X system 450 is illustrated for communication between vehicles 452 and 454 via network entity 456. This network communication can occur via discrete nodes such as BS (e.g., eNB or gNB) that send and receive information to and from vehicles 452 and 454 (e.g., relaying information between vehicles 452 and 454). Network communication via vehicle-to-network (V2N) links 458 and 410 can be used for, for example, long-distance communication between vehicles, such as transmitting information about a car accident some distance ahead along a road or highway. Other types of communication can be sent from nodes to vehicles, such as traffic flow conditions, road hazard warnings, environmental / weather reports, and service station availability, among other examples. Such data may be obtained from cloud-based shared services.

[0073] As described above, V2V and V2X communications are examples of communications that can be sent via SL. Other applications of SL communications can include public safety or service announcement communications, communications for proximity services, communications for UE-to-network relay, device-to-device (D2D) communications, Internet of Things (IoE) communications, Internet of Things (IoT) communications, mission-critical mesh communications, and other suitable applications. Typically, SL can refer to a direct link between one dependent entity (e.g., UE1) and another dependent entity (e.g., UE2).

[0074] Various SL channels can be used for SL communication, including the Physical Side Link Discovery Channel (PSDCH), Physical Side Link Control Channel (PSCCH), Physical Side Link Shared Channel (PSSCH), and Physical Side Link Feedback Channel (PSFCH). The PSDCH can carry discovery expressions that enable near-end devices to discover each other. The PSCCH can carry control signaling, such as SL resource configurations and other parameters for data transmission, while the PSSCH can carry data transmission itself.

[0075] Regarding PSSCH operations, the UE can perform transmission or reception on a carrier within a time slot. For the UE, NR SL can support a case where all symbols in a time slot are available for SL, and another case where only a subset of consecutive symbols in a time slot are available for SL.

[0076] The PSFCH can carry feedback, such as CSI related to the SL channel quality. Sequence-based PSFCH formats with one symbol (excluding the automatic gain control (AGC) training period) can be supported. The following formats are possible: PSFCH formats based on PUCCH format 2, and PSFCH formats spanning all available symbols for SL in the time slot.

[0077] In NR, there are typically two basic SL resource allocation modes. Figure 5A and Figure 5B Two SL communication modes are shown in accordance with certain aspects of this disclosure. The RX UE behavior can be identical for both SL resource allocation modes.

[0078] According to the first mode (Mode 1 (e.g., centralized mode)), such as Figure 5A As shown, the BS can allocate SL resources for SL communication between UEs. For example, the BS can send downlink control information (e.g., DCI 3_0) to allocate time and frequency resources and indicate transmission timing. The modulation and coding scheme (MCS) can be determined by the UE within constraints set by the BS.

[0079] In some cases, Mode 1 can support Dynamic Grant (DG) and Configuration Grant (CG) (e.g., CG Type 1 and CG Type 2). CG Type 1 can be activated via Radio Resource Control (RRC) signaling from the BS.

[0080] According to the second mode (mode 2 (e.g., distributed mode)), such as Figure 5B As shown, the UE can determine the SL resource (the BS does not schedule SL transmission resources within the SL resources configured by the BS / network). In this case, the UE can autonomously select the SL resource for transmission (following some rules in the NR standard). The UE can assist in the selection of SL resources for other UEs. The UE can be configured with NR configuration permissions for SL transmission, and the UE can schedule SL transmissions for other UEs.

[0081] In some cases, a V2X UE can perform channel sensing by blindly decoding all PSCCH channels to determine which resources are reserved by other UEs for other SL transmissions. In this scenario, the V2X UE may be required to perform sensing and receiving continuously, which can be very power-intensive. However, it may be desirable to monitor messages only during certain time-frequency resource periods of the channel to reduce power consumption at the UE.

[0082] Power-saving configurations can be configured for sidelinks to allow wireless devices to power down one or more RF components when not in use, thereby saving power. Specifically, 3GPP Release 17 systems focus on power-saving techniques in non-vehicle applications such as public safety applications, commercial use cases, and wearable devices. Such systems seek to achieve maximum power savings at the physical / medium access control (MAC) layer. In some examples, power-saving configurations may use partial sensing. In some examples, power-saving configurations may use discontinuous reception (DRX) cycling.

[0083] Figure 6 An example SL DRX configuration 600 for a UE is shown. As illustrated, SL DRX configuration 600 may include SL DRX on (e.g., wake-up phase) durations 602, 604 (also referred to as DRX on phases). As described herein, the SL DRX on phase may repeat in each DRX cycle. For example, DRX on duration 602 may be during DRX cycle 406, as illustrated. The TX UE may be awake during DRX on durations 602, 604 to communicate with another RX UE for unicast, or with multiple RX UEs for broadcast and multicast (e.g., the RX UE monitors for signaling that can be received from the TX UE), and both the TX UE and RX UE may be in a low-power state (e.g., sleep phase) at other times (also referred to as SL DRX off durations or SLDRX off phases). Furthermore, a UE may become a TX UE on the SL when a UE in a service, group, or UE pair has packets to send on the SL to other UEs in the service or group or other UEs in the UE pair. Therefore, unlike DRX, which is used by the UE to monitor downlink control information (DCI) from network entities at the Uu interface, SL DRX can be bidirectional on the SL for both TX UE and RX UE; and therefore, SL DRX can form SL service modes for services, groups or UE pairs.

[0084] To further reduce the workload of the UE for receiving data, the UE can be configured with an SL WUS configuration by avoiding unnecessary waking up of the UE or keeping the UE awake. Therefore, various aspects of this disclosure provide SL WUS configurations for improving power efficiency in SL communications.

[0085] Example design considerations for sidelink (SL) wake-up signal (WUS)

[0086] The techniques described herein can use a sidelink (SL) wake-up signal (WUS) to indicate to a radio node (such as a user equipment (UE) participating in SL communication) whether an upcoming control channel signaling resource includes information relevant to the UE. The SL WUS can be designed to account for detection performed by the UE with relatively simple, low-power processing. In this way, the UE can be more fully woken up to perform complex control channel signaling processing only when the control channel includes signals relevant to the UE, thereby conserving UE battery power and resources.

[0087] Figure 7This is a schematic diagram illustrating a timeline 700 of an example SL WUS configuration according to certain aspects of this disclosure. As shown, the SL WUS configuration may include WUS monitoring times 702, 704, and 706. As described herein, WUS monitoring times may repeat in each WUS period. In some examples, the UE may only wake up a low-power WUS receiver to perform monitoring during WUS monitoring times 702, 704, and 706 (one or a subset of WUS monitoring times 702, 704, and 706).

[0088] If the UE does not detect WUS during a WUS monitoring period, as shown in WUS monitoring period 702, the UE can remain in a low-power (sleep) state, during which all RF components are powered down. If the UE detects WUS during a WUS monitoring period, as shown in WUS monitoring period 704, the UE can remain awake and communicate with another receiver (RX) UE for unicast or with an RX UE for broadcast and multicast. The UE can remain awake during the WUS period to determine whether WUS is detected in subsequent monitoring periods (such as WUS monitoring period 706), and if no WUS is detected after a previous WUS monitoring period in which WUS was detected, it decides to return to the sleep phase.

[0089] Figure 8 This is a flowchart illustrating an example operation 800 for wireless communication by a first UE according to certain aspects of this disclosure. Operation 800 may be performed, for example, by a wireless node (e.g., UE 120a such as in wireless communication network 100). Operation 800 may be implemented in one or more processors (e.g., Figure 2 The software components executed and running on the controller / processor 280. Further, in operation 800, the transmission and reception of signals by the wireless node can, for example, be via one or more antennas (e.g., Figure 2 This can be achieved via antenna 252. In some aspects, the transmission and / or reception of signals by the wireless node can be achieved via a bus interface that receives and / or outputs signals from one or more processors (e.g., controller / processor 280).

[0090] At box 805, operation 800 may begin by determining the resources for SLWUS transmissions from the second UE based on WUS resource configuration.

[0091] At box 810, the first UE monitors resources for the SL WUS from the second UE.

[0092] At box 815, if SL WUS is detected during monitoring, the first UE participates in SL communication with the second UE.

[0093] Figure 9 This is a flowchart illustrating example operation 900, which can be considered as... Figure 8 Operation 800 is complementary. For example, operation 900 can be executed by a second UE to execute... Figure 8 Operation 800 involves the first UE sending an SL WUS (and performing SL communication with the first UE). Operation 900 can be performed, for example, by a remote UE (e.g., UE 120a in wireless communication network 100). Operation 900 can be implemented in one or more processors (e.g., Figure 2 Software components executed and running on the controller / processor 280. Further, in operation 900, the transmission and reception of signals by the remote UE can, for example, be via one or more antennas (e.g., Figure 2 This can be achieved via antenna 252. In some aspects, the transmission and / or reception of signals by a remote UE can be achieved via a bus interface that obtains and / or outputs signals through one or more processors (e.g., controller / processor 280).

[0094] At box 905, operation 900 can begin by determining the resources for SLWUS transport to the first UE based on WUS resource configuration.

[0095] At box 910, the second UE sends SL WUS to the first UE on the determined resource.

[0096] At frame 915, the second UE participates in SL communication with the first UE after sending SL WUS.

[0097] Figure 8 Operation 800 and Figure 9 Operation 900 can be used as a reference Figure 10A To understand this, refer to call flowcharts 1000A and 10B, specifically call flowchart 1000B. Figure 10A and Figure 10B Example SL communications for one-way and two-way WUS configuration between UEs are shown respectively, according to certain aspects of this disclosure.

[0098] As mentioned above, when a UE in a service, group, or UE pair has a packet to send to other UEs in the service or group, or other UEs in the UE pair, it can initiate an SL transmission (becoming a TX UE on the SL). Therefore, unlike downlink (DL) scenarios where a network entity (e.g., BS) is responsible for determining the WUS configuration and sending the WUS configuration at the Uu interface, SLWUS can be unidirectional or bidirectional for both the TX UE and the RX UE (either UE in the SL pair can send SLWUS).

[0099] like Figure 10A As shown, in a one-way WUS scenario, one UE can configure another UE for SL WUS and send SL WUS to another UE (this can be similar to the BS configuration and DL WUS configuration for sending WUS). When an SL connection is established between two UEs (e.g., during the SL discovery process), the UEs can negotiate to determine which UE will send SL WUS and which UE will receive SL WUS. In a one-way WUS scenario, the determined WUS RX UE may not send SL WUS; only the WUS TX UE can send SL WUS.

[0100] In this scenario, the first UE (e.g., SL WUS TX UE) can send SL WUS to the second UE (e.g., SL WUS RX UE). After receiving the SL WUS, the second UE can send it back to the first UE at any given time (subject to the discontinuous reception (DRX) constraint at the WUS TX UE). The second UE may be less capable than the first UE (e.g., in terms of battery power). In such a case, based on the presence of SL WUS, the second UE can assume that the first UE is always awake (i.e., the SL WUS TX UE does not participate in power saving), or that the first UE will be awake for a certain amount of time. Based on this assumption, the second UE will not need to send WUS back to the first UE (which is why this scenario can be called a one-way WUS scenario).

[0101] like Figure 10B As shown, the configuration and transmission of WUS can be bidirectional, where both UEs can send their own SL WUS.

[0102] Depending on one option, the wake-up state can be defined only in one direction. For example, if a service arrives at a first UE (e.g., SL WUS TX UE), the first UE can send an SL WUS to a second UE (e.g., SL WUS RX UE). The second UE can monitor for SL WUS during WUS monitoring. When WUS is detected, the second UE can receive only the transmission from the first UE. Because the wake-up state is defined only in one direction, the second UE may not send SL transmissions to the first UE except for sending an SL Hybrid Automatic Repeat Request (HARQ) acknowledgment (ACK) feedback. The second UE may need to send an SL WUS to the first UE in order to send data back to the first UE.

[0103] According to another option, the wake-up state can be defined in two directions. For example, if a service arrives at a first UE (e.g., SL WUS TX UE), the first UE can send an SL WUS to a second UE (e.g., SL WUS RX UE), similar to the example where the wake-up state is defined in one direction. However, when the wake-up state is defined in two directions, the sent SL WUS can be used to wake up both the first UE and the second UE (e.g., wake up both the SL WUS TX UE and the SL WUS RX UE). Therefore, the SL WUS can be used to wake up both the transmitter and receiver components at the first UE (and similarly, both the transmitter and receiver components at the second UE), thereby allowing the second UE to transmit and receive from the first UE, and vice versa.

[0104] Depending on certain aspects, WUS resource configuration can be configured jointly with SL DRX configuration. Figure 11 This is a schematic diagram 1100 illustrating an example SL WUS configuration combining DRX cycles according to certain aspects of this disclosure. Combining SL DRX and SLWUS can reduce the workload of remote UEs for receiving data, avoiding unnecessary wake-ups or stay-on states.

[0105] In other words, jointly configuring WUS resource configuration with SL DRX configuration can add an additional power-saving layer before each SL DRX on duration. As submitted above, the SL DRX on duration (and SL DRX off duration) can be repeated for each SL DRX cycle. When WUS configuration is jointly configured with SL DRX configuration, WUS resource configuration can indicate one or more WUS monitoring opportunities within a time slot for the first UE to monitor.

[0106] WUS monitoring can occur periodically during the SL DRX off duration configured in the SL DRX configuration (and before each SL DRX on duration). If an SL WUS is detected during monitoring during a WUS monitoring period, the UE can wake up and enter the DRX on state. If no SL WUS is detected during monitoring during a WUS monitoring period, the UE can choose not to enter the DRX on state and can remain in a low-power state for the SL DRX on duration configured in the SL DRX configuration (i.e., remain in a low-power state until the next WUS monitoring period). Therefore, this joint configuration allows the UE to avoid unnecessary wake-ups and / or remaining awake, thereby further reducing the workload of remote UEs for receiving.

[0107] SL WUS can be configured and sent on dedicated (periodic) resources. Figure 12A and Figure 12B Example options for configuring SL WUS resources for a cycle, based on certain aspects of this disclosure, are shown.

[0108] According to the first WUS resource configuration option, dedicated resources can be decoupled from the resource pool configuration, such as... Figure 12A As shown. In other words, SL WUS resources can be configured in a bandwidth portion (BWP) or an SL carrier, as well as in any resource pool that is not included / configured in a BWP or SL carrier. In some aspects, SL WUS can also be applied to other BWPs or SL carriers. For example, an SL WUS RX UE can monitor / receive SL WUS for SL WUS in one BWP, and wake up to receive transmissions from other BWPs.

[0109] In some examples, WUS resources can be configured as narrowband, and the SL WUS RX UE can receive SL WUS only by enabling the RF for narrowband. In such cases, the SL WUS RX UE can monitor for SL WUS with a first RF bandwidth setting based on the BWP or SL carrier in which the WUS resources are configured, and if WUS is detected by the SL WUS RX UE, the SL WUS RX UE can enable another RF component to participate in SL communication with the SL WUS TX UE using a second RF bandwidth setting that is wider than the first RF bandwidth setting (e.g., after the SL WUS RX UE has detected SLWUS, the SL WUS TX UE can monitor for SLWUS with a narrower bandwidth setting than the bandwidth setting used for receiving packets).

[0110] According to the second WUS resource configuration option, dedicated resources for SL WUS can be included / configured in a WUS resource pool shared by multiple UEs. For example... Figure 12B As shown, different WUS monitoring times can be assigned to different UEs; for example, each UE pair can be allocated SL WUS times every two time slots. As a result, the monitoring times for a UE pair can be relatively long, for example, every thirty time slots. Therefore, the UE pair can wake up only during the selected WUS monitoring times. Figure 12B In the example shown, the first pair of UEs, 1 and 2, are assigned the first WUS monitoring opportunity, while the second pair of UEs, 3 and 4, are assigned the second WUS monitoring opportunity, as shown. Figure 12B As shown. For this resource configuration option, if the UE is configured (or pre-configured) with WUS functionality (e.g., pre-configured with WUS resource configuration), then at least one resource pool can be configured with WUS resources.

[0111] According to the second WUS resource configuration option, the WUS resource allocation indication can indicate one or more WUS monitoring opportunities within a time slot for the SL WUS RX UE to perform monitoring.

[0112] Figures 13A-13C This illustration shows an example time slot format when WUS resources are included in a WUS resource pool shared by multiple UEs, according to certain aspects of this disclosure. As shown, one or more types of physical SL channels (e.g., PSSCH, PSCCH, and / or PSFCH) can be rate-matched around resources at one or more WUS monitoring times within a time slot.

[0113] The time-slot format can also provide the interval between WUS monitoring and PSSCH. For example, as... Figure 13A As shown, the new slot format defined for WUS containing slot may include a WUS occupying several symbols in the time domain (including an automatic gain control (AGC) symbol preceding the WUS and a slot symbol at the end of the WUS), while the remainder of the slot is used for PSSCH / PSCH, followed by the slot symbol.

[0114] As another example, such as Figure 13B As shown, a new time-slot format for WUS containing time-slot definitions can include multiple WUS monitoring events, in which each WUS occupies several symbols in the time domain (including the AGC symbol preceding the WUS and the gap symbol at the end of the WUS), and multiple such WUS occupying the entire time slot (e.g., in...). Figure 13B In the middle, three WUS occupies the entire time slot.

[0115] As another example, such as Figure 13C As shown, the new slot format for WUS containing slot definitions can include a WUS occupying several symbols in the time domain (including the ACG symbol before the WUS and the gap symbol at the end of the WUS), a PSSCH / PSCCH occupying several symbols in the time domain (followed by the gap symbol), and a PSFCH occupying several symbols in the time domain (followed by the gap symbol), thereby filling the entire slot.

[0116] Based on WUS configuration, a UE pair can determine which WUS resources to use (for transmission or for monitoring transmission). As described above, the actual resources used by the UE pair / set to send and / or receive WUS may only be a subset of the available WUS resources. In other words, the WUS timing configured in the time domain may be much more time-intensive than the actual periodicity used by the UE pair / set. UE pairs / sets (e.g., SL WUS TX UE and SL WUS RX UE) can use additional rules to determine which subset of available WUS resources the pair / set can use / monitor as WUS timing. This determination may differ for UE pairs in unicast compared to UE pairs receiving WUS resource configurations via broadcast, multicast, or multicast signaling.

[0117] Figure 14 This illustration shows an example subset of available WUS resources for transmitting and / or receiving WUS, according to certain aspects of this disclosure. A pair including UE 1 and UE 2 can be woken up and monitored during a first WUS monitoring event, and a pair including UE 3 and UE 4 can be woken up and monitored during a second WUS monitoring event. Therefore, each pair can use only a subset of the available resources configured for WUS monitoring / transmission.

[0118] In cases where TX / RX UEs are communicating via broadcast, multicast, or multicast signaling, one TX UE (e.g., an SL WUS TX UE) can communicate with multiple RX UEs (e.g., SL WUS RX UEs). Therefore, SL WUS can be sent from the TX UE to multiple RX UEs. In this case, the actual WUS resources / timing used by the TX UE can be based on a Layer 2 (L2) identifier (ID). When the TX / RX UEs are communicating via broadcast, the L2 ID can be derived from the application that triggered the UE to send the block message (i.e., determined by the TX UE). When the TX / RX UEs are communicating via multicast, the L2 ID can be derived from the group information ID established between the TX UE and a group of RX UEs (i.e., determined by the TX UE). When the TX / RX UEs are communicating via connectionless multicast, the L2 ID can be derived based on the service type (i.e., determined by the TX UE).

[0119] Figure 15A This illustration depicts communication between UEs in unicast mode, according to certain aspects of this disclosure. In the case of a UE pair in unicast mode, the WUS resources / timings to be used / monitored can be based on the source / destination IDs established during the PC5 (SL interface) connection setup between the UE pair. Two approaches can be considered for selecting the WUS timings / resources to be used / monitored (e.g., an indication of the resources a UE can use to send SL WUS for SL WUS TX, and an indication of the timings a UE can monitor for SL WUS for SL WUS RX).

[0120] Figure 15B and Figure 15C Example options for selecting WUS resources during unicast communication between UEs are shown, according to certain aspects of this disclosure. For example... Figure 15B As shown, according to the first approach, the network entity can determine an indication of the resources / timing to be used / monitored and signal the indication of the resources / timing to be used / monitored. In some examples, the network entity can determine the WUS resources / timing based on resources selected / preferred by one of the SL WUS RX UEs, the WUS resources / timing being indicated to the SL WUS TX UE and relayed to the network entity.

[0121] like Figure 15CAs shown, according to the second approach, WUS resources / timing can be selected by the UE itself (in the absence of a network entity). In some examples, the UE can determine WUS resources / timing based on the identifiers (IDs) of the SL WUS TX UE and the SL WUS RX UE (e.g., source and destination IDs). Alternatively, in some other examples, either the SL WUS TX UE or the SL WUS RX UE can indicate a preference for resources to be used for SL WUS resources / timing, and the other SL WUS RX UE can make the final decision regarding the resources / timing to be used for SL WUS transmissions / monitoring for SL WUS transmissions.

[0122] When WUS is configured jointly with DRX, the WUS timing can be determined based on the DRX cycle and the DRX on-time duration. For example, the WUS cycle can be the same as the DRX cycle, or the WUS periodicity can include multiple DRX cycles. The WUS monitoring timing can occur (periodically) in a threshold number of slots / symbols before the start of each SL DRX on-time duration. The TX / RX UE can know the WUS timing used before each DRX on-time duration. This approach is efficient because it eliminates the need for separate indication of the WUS timing.

[0123] In some cases, SL WUS can be transmitted by the SL WUS TX UE via sidelink control information (SCI) or by a sequence. The SCI or sequence may indicate at least one bit for wake-up indication and one or more bits indicating at least one of BWP, resource pool, or component carrier (CC) ID. Sequence-based WUS may contain ten or fewer bits, while SCI-based WUS may be able to transmit more than ten bits.

[0124] For both SCI-based WUS and sequence-based WUS, SL WUS can be scrambled by at least one of the following: destination ID, group destination ID, or dedicated scrambling ID / Radio Network Temporary Identifier (RNTI). The dedicated scrambling ID can be configured for UE pairs used for unicast, for a group of UEs used for managed multicast, or for an application. Therefore, SL WUS does not need to transmit explicit source or destination IDs. This can help reduce the payload size of SL WUS. Furthermore, scrambling SL WUS can help prevent unnecessary wake-ups of other UEs. SL WUS can be designed only for one SLWUS RX UE, and only the intended SL WUS RX UE may be able to decode SL WUS. Therefore, other UEs may not be able to decode / descramble SL WUS because they may not know the IDs of the SL WUS TX UE and SL WUS RX UE.

[0125] Because SL involves multiple UEs (which can now know the locations of other UEs), there is an increased probability of collisions in the transmitted SL WUS. Therefore, SL WUS may be less reliable than Uu-WUS. Thus, depending on certain aspects, the SL WUS RX UE can provide ACK feedback for the received SL WUS (e.g., HARQ-ACK feedback only). If no ACK is sent, the SL WUS TX UE can retransmit the SL WUS to increase its reliability.

[0126] Figure 16 Examples are shown in which PSFCH can be used in an SL WUS configuration, according to certain aspects of this disclosure. In some examples, such as Figure 16 As shown, the SL WUS RX UE can monitor for SL WUS during WUS monitoring. When SL WUS is not detected, the SL WUS RX UE may not send an ACK feedback, depending on certain factors. Because the SL WUS TX UE may not receive the ACK feedback, the SL WUS TX UE can retransmit SL WUS. Alternatively, when the SL WUS RX UE detects SL WUS, the SL WUS RX UE can send a PSFCH (feedback) back to the SL WUS TX UE.

[0127] Alternatively, in some examples, the SL WUS TX UE can be configured to transmit SL WUS multiple times using repetition (without using PSFCH feedback from the SL WUS RX UE). While this can increase the reliability of SL WUS reception, it may increase the number of resources / repetitions required to transmit SL WUS more than once.

[0128] Figure 17 A communication device 1700 is shown, which may include operations configured to perform the techniques disclosed herein (such as in...). Figure 8 The communication device 1700 includes various components (e.g., corresponding to functional module components) shown in the diagram. The communication device 1700 includes a processing system 1702 coupled to a transceiver 1708 (e.g., a transmitter and / or receiver). The transceiver 1708 is configured to transmit and receive signals for the communication device 1700 via an antenna 1710, such as the various signals described herein. The processing system 1702 can be configured to perform processing functions for the communication device 1700, including processing signals received and / or to be transmitted by the communication device 1700.

[0129] Processing system 1702 includes processor 1704 coupled to computer-readable medium / memory 1712 via bus 1706. In some aspects, computer-readable medium / memory 1712 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1704, cause processor 1704 to perform... Figure 8 The operations shown herein, or other operations used to perform the various techniques discussed herein. In some aspects, the computer-readable medium / memory 1712 stores code 1714 for determining (e.g., for determining resources for SL WUS transmission from the second UE based on WUS resource configuration); code 1716 for monitoring (e.g., for monitoring resources for SL WUS from the second UE); and code 1718 for participating (e.g., for participating in SL communication with the second UE if SL WUS is detected during monitoring). In some aspects, the processor 1704 has circuitry configured to implement the code stored in the computer-readable medium / memory 1712. The processor 1704 includes circuitry 1724 for determining (e.g., for determining resources for SL WUS transmission from the second UE based on WUS resource configuration); circuitry 1726 for monitoring (e.g., for monitoring resources for SL WUS from the second UE); and circuitry 1728 for participating (e.g., for participating in SL communication with the second UE if SL WUS is detected during monitoring).

[0130] Figure 18A communication device 1800 is shown, which may include operations configured to perform the techniques disclosed herein (such as in...). Figure 9 The communication device 1800 includes various components (e.g., corresponding to functional module components) shown in the diagram. The communication device 1800 includes a processing system 1802 coupled to a transceiver 1808 (e.g., a transmitter and / or receiver). The transceiver 1808 is configured to transmit and receive signals for the communication device 1800 via an antenna 1810, such as the various signals described herein. The processing system 1802 can be configured to perform processing functions for the communication device 1800, including processing signals received and / or to be transmitted by the communication device 1800.

[0131] Processing system 1802 includes processor 1804 coupled to computer-readable medium / memory 1812 via bus 1806. In some aspects, computer-readable medium / memory 1812 is configured to store instructions (e.g., computer-executable code) that, when executed by processor 1804, cause processor 1804 to perform actions... Figure 9 The operations shown herein, or other operations used to perform the various techniques discussed herein. In some aspects, the computer-readable medium / memory 1812 stores code 1814 for determining (e.g., determining resources for SL WUS transmission to the second UE based on WUS resource configuration); code 1816 for transmitting (e.g., transmitting SL WUS to the second UE); and code 1818 for participating (e.g., participating in SL communication with the second UE). In some aspects, the processor 1804 has circuitry configured to implement the code stored in the computer-readable medium / memory 1812. The processor 1804 includes circuitry 1824 for determining (e.g., determining resources for SL WUS transmission to the second UE based on WUS resource configuration); circuitry 1826 for transmitting (e.g., transmitting SL WUS to the second UE); and circuitry 1828 for participating (e.g., participating in SL communication with the second UE).

[0132] Example

[0133] Aspect 1: An apparatus for wireless communication by a first user equipment (UE), comprising: a memory and at least one processor coupled to the memory, the memory and at least one processor being configured to: determine resources for side-link (SL) WUS transmissions from a second UE based on wake-up signal (WUS) resource configuration; monitor resources for SL WUS from the second UE; and participate in SL communication with the second UE if SL WUS is detected during monitoring.

[0134] Aspect 2: According to the apparatus of aspect 1, wherein the first UE is pre-configured with WUS resource configuration.

[0135] Aspect 3: The apparatus according to aspect 1 or aspect 2, wherein participating in SL communication with the second UE includes sending SL transmissions to the second UE.

[0136] Aspect 4: The apparatus according to any of aspects 1-3, wherein participating in SL communication with the second UE includes receiving SL transmissions from the second UE.

[0137] Aspect 5: According to the apparatus of aspect 4, the participation in SL communication with the second UE further includes: sending SLWUS to the second UE; and sending SL transmission to the second UE after sending SL WUS to the second UE.

[0138] Aspect 6: The apparatus according to any of Aspects 1-5, wherein participating in SL communication with the second UE includes sending SL transmission to the second UE without sending SL WUS to the second UE.

[0139] Aspect 7: An apparatus according to any of Aspects 1-6, wherein the WUS resource configuration indicates resources in at least one of the bandwidth portion (BWP) or SL carrier.

[0140] Aspect 8: The apparatus according to aspect 7, wherein: the memory and at least one processor are configured to monitor for SL WUS using a first radio frequency (RF) bandwidth setting based on a BWP or SL carrier; and the memory and at least one processor are configured to participate in SL communication with a second UE using a second RF bandwidth setting that is wider than the first RF bandwidth setting.

[0141] Aspect 9: An apparatus according to any of Aspects 1-8, wherein the WUS resource configuration indicates resources in a WUS resource pool shared by multiple UEs.

[0142] Aspect 10: According to the apparatus of aspect 9, wherein the WUS resource configuration indicates one or more WUS monitoring opportunities for the first UE to monitor within a time slot.

[0143] Aspect 11: According to the apparatus of aspect 10, wherein one or more types of physical SL channels are rate matched around resources for one or more WUS monitoring opportunities within a time slot.

[0144] Aspect 12: According to the apparatus of aspect 11, wherein the format of the time slot provides a gap between at least one WUS monitoring opportunity and the physical side crosslink shared channel (PSSCH) in one or more WUS monitoring opportunities.

[0145] Aspect 13: An apparatus according to any of aspects 1-12, wherein the memory and at least one processor are further configured to receive WUS resource configuration from a second UE via broadcast, multicast or multicast signaling.

[0146] Aspect 14: According to the apparatus of aspect 13, the resource for monitoring SL WUS transmissions from the second UE is determined further based on the layer 2 (L2) identifier (ID) of the second UE.

[0147] Aspect 15: The apparatus according to any of aspects 1-14, wherein: the resource to be monitored for SLWUS transmissions from the second UE is selected by at least one of the first UE or the second UE.

[0148] Aspect 16: According to the apparatus of aspect 15, the resources to be monitored for SL WUS transmissions from the second UE are selected based on the identifiers of the first UE and the second UE.

[0149] Aspect 17: The apparatus according to aspect 15 or aspect 16, wherein: one of the first UE or the second UE indicates a preference for resources to be used for SL WUS transmissions from the second UE; and the first UE or the second UE that does not indicate a preference makes a final decision regarding the resources to be used for SL WUS transmissions from the second UE.

[0150] Aspect 18: An apparatus according to any of aspects 15-17, wherein the memory and at least one processor are further configured to: receive network signaling indicating resources to be monitored for SL WUS transmissions from a second UE.

[0151] Aspect 19: An apparatus according to any of Aspects 1-18, wherein: the WUS resource configuration is configured in conjunction with the SL DRX configuration; and the memory and at least one processor are configured to determine the timing of the WUS to be monitored based on the SL DRX cycle and the SL DRX on duration of the SL DRX configuration.

[0152] Aspect 20: The apparatus according to aspect 18, wherein the memory and at least one processor are configured to: monitor resources for SL WUS from a second UE during the SL DRX off duration configured in the SL DRX configuration; and remain in a low-power state during the SL DRX on duration configured in the SL DRX configuration, unless SL WUS is detected during the monitoring.

[0153] Aspect 21: The apparatus according to any of aspects 1-20, wherein the SL WUS is transmitted via at least one of side link control information (SCI) or sequence.

[0154] Aspect 22: The apparatus according to aspect 21, wherein the SCI or sequence indicator is at least one bit for wake-up indication and one or more bits indicating at least one of the bandwidth portion (BWP), resource pool or component carrier (CC) identifier (ID).

[0155] Aspect 23: The apparatus according to aspect 21 or aspect 22, wherein the SCI or sequence is scrambled by at least one of destination ID, group destination ID or dedicated scrambling ID.

[0156] Aspect 24: According to the apparatus of aspect 23, the dedicated scrambling ID is configured for at least one of a first UE and a second UE for unicast, for a group of UEs for managed multicast, or for an application.

[0157] Aspect 25: An apparatus according to any of aspects 1-24, wherein the memory and at least one processor are further configured to provide acknowledgment (ACK) feedback for SL WUS.

[0158] Aspect 26: The apparatus according to any of aspects 1-25, wherein SL WUS is transmitted using multiple repetitions within the WUS timing.

[0159] Aspect 27: An apparatus for wireless communication by a second user equipment (UE), comprising: a memory and at least one processor coupled to the memory, the memory and at least one processor being configured to: determine, based on wake-up signal (WUS) resource configuration, resources for side-link (SL) WUS transmission to a first UE; transmit the SL WUS to the first UE on the determined resources; and participate in SL communication with the first UE after transmitting the SL WUS.

[0160] Aspect 28: The apparatus according to aspect 27, wherein the WUS resource configuration indicates resources in at least one of a WUS resource pool, a bandwidth portion (BWP), or an SL carrier shared by multiple UEs.

[0161] Aspect 29: A method for wireless communication by a first user equipment (UE), comprising: determining resources for sidelink (SL) WUS transmission from a second UE based on wake-up signal (WUS) resource configuration; monitoring resources for SL WUS from the second UE; and engaging in SL communication with the second UE if SL WUS is detected during monitoring.

[0162] Aspect 30: A method for wireless communication by a second user equipment (UE), comprising: determining, based on wake-up signal (WUS) resource configuration, resources for side-link (SL) WUS transmission to a first UE; transmitting the SL WUS to the second UE on the determined resources; and participating in SL communication with the second UE after transmitting the SL WUS.

[0163] Other considerations

[0164] The techniques described in this document can be used in a variety of wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), Improved LTE (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), Time Division Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms "network" and "system" are often used interchangeably. CDMA networks can implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers the IS-2000, IS-95, and IS-856 standards. TDMA networks can implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA networks can implement radio technologies such as NR (e.g., 5G RA), evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDMA. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are versions of UMTS using E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the 3rd Generation Partnership Project (3GPP). CDMA2000 and UMB are described in documents from an organization called the 3rd Generation Partnership Project 2 (3GPP2). NR is an emerging wireless communication technology currently being deployed.

[0165] In 3GPP, the term "cell" can refer to the coverage area of ​​a Node B (NB) and / or the NB subsystem serving that coverage area, depending on the context in which the term is used. In NR systems, the term "cell" is used interchangeably with BS, Next Generation Node B (gNB or gNodeB), Access Point (AP), Distributed Unit (DU), and Carrier or Transmit / Receive Point (TRP). A BS can provide communication coverage for macrocells, picocells, femtocells, and / or other types of cells. A macrocell can cover a relatively large geographic area (e.g., a radius of several kilometers) and can allow unrestricted access by UEs with service subscriptions. A picocell can cover a relatively small geographic area and can allow unrestricted access by UEs with service subscriptions. A femtocell can cover a relatively small geographic area (e.g., a residential area) and can allow restricted access by UEs associated with that femtocell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for users in a residential area, etc.). A BS used for a macrocell can be called a macro BS. A BS used for a picocell can be called a pico BS. A BS used for a femtocell can be called a femtocell BS or a home BS.

[0166] A UE can also be referred to as a mobile station, terminal, access terminal, subscriber unit, station, customer premises equipment (CPE), cellular phone, smartphone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, laptop computer, cordless phone, wireless local loop (WLL) station, tablet computer, camera, gaming device, netbook, smartbook, ultrabook, appliance, medical device or medical equipment, biometric sensor / device, wearable device (such as smartwatch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio unit, etc.), vehicle component or sensor, smart meter / sensor, industrial manufacturing equipment, GPS device, or any other suitable device configured to communicate via wireless or wired media. Some UEs can be considered machine-type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTCUE include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., which can communicate with the BS, another device (e.g., a remote device), or some other entity. Wireless nodes can provide connectivity to or to a network (e.g., a wide area network such as the Internet or cellular networks) via wired or wireless communication links. Some UEs can be considered Internet of Things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

[0167] The methods disclosed herein include one or more steps or actions for implementing the methods. Method steps and / or actions can be interchanged with each other. In other words, the order and / or use of specific steps and / or actions can be modified unless a specific order of steps or actions is specified.

[0168] As used herein, the phrase “at least one of” in a list of items refers to any combination of those items, including a single member. For example, “at least one of the following: a, b, or c” is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc, or any other ordering of a, b, and c).

[0169] As used herein, the term "determine" encompasses a wide variety of actions. For example, "determine" can include calculation, operation, processing, derivation, investigation, lookup (e.g., searching in a table, database, or other data structure), ascertainment, etc. Furthermore, "determine" can include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), etc. Additionally, "determine" can include parsing, selecting, choosing, establishing, etc.

[0170] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Unless specifically stated otherwise, references to elements in the singular form are not intended to mean “one and only one” but rather “one or more.” Unless otherwise expressly stated, the term “some” refers to one or more. All structural and functional equivalents of the elements throughout the various aspects described in this disclosure are expressly incorporated herein by reference and intended to be included by the claims, and are known or to be known by those skilled in the art. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is expressly recited in the claims. No claim element is to be interpreted pursuant to 35 U.SC §112(f) unless the element is expressly recited using the phrase “unit for…” or, in the case of a method claim, using the phrase “step for…”.

[0171] The various operations of the methods described above can be performed by any suitable unit capable of performing the corresponding functions. Units may include various hardware and / or software components and / or modules, including but not limited to circuits, application-specific integrated circuits (ASICs), or processors. Typically, in the presence of operations as shown in the figures, those operations may have corresponding paired functional module components with similar numbering.

[0172] The various illustrative logic blocks, modules, and circuits described in connection with this disclosure can be implemented or executed using a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general-purpose processor may be a microprocessor, but alternatively, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0173] If implemented in hardware, an example hardware configuration could include a processing system in a wireless node. The processing system could be implemented using a bus architecture. Depending on the specific application and overall design constraints of the processing system, the bus could include any number of interconnect buses and bridges. The bus could link together various circuits, including a processor, machine-readable media, and a bus interface. In addition, the bus interface could be used to connect a network adapter to the processing system via the bus. The network adapter could be used to implement physical layer signal processing functions. In user terminal 120 (see...) Figure 1 In this case, a user interface (e.g., keypad, display, mouse, joystick, etc.) can also be connected to the bus. The bus can also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, etc., which are well known in the art and therefore will not be described further. The processor can be implemented using one or more general-purpose and / or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits capable of executing software. Those skilled in the art will recognize how the functionality described for the processing system can be optimally implemented depending on the specific application and the overall design constraints imposed on the system as a whole.

[0174] If implemented in software, the functionality can be stored on or transmitted via a computer-readable medium as one or more instructions or code. Whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise, software should be broadly interpreted to mean instructions, data, or any combination thereof. Computer-readable media includes both computer storage media and communication media, with communication media encompassing any medium that facilitates the transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general-purpose processing, including the execution of software modules stored on the machine-readable storage medium. The computer-readable storage medium may be coupled to the processor, allowing the processor to read information from and write information to it. Alternatively, the storage medium may be an integral part of the processor. For example, the machine-readable medium may include a transmission line, a carrier wave modulated by data, and / or a separate computer-readable storage medium containing instructions stored thereon, all accessible to the processor via a bus interface. Alternatively or additionally, the machine-readable medium or any portion thereof may be integrated into the processor, such as in the case of a cache and / or a general-purpose register file. For example, examples of machine-readable storage media may include RAM (random access memory), flash memory, ROM (read-only memory), PROM (programmable read-only memory), EPROM (erasable programmable read-only memory), EEPROM (electrically erasable programmable read-only memory), registers, disks, optical disks, hard disks, or any other suitable storage media, or any combination thereof. Machine-readable media may be embodied in a computer program product.

[0175] Software modules may include a single instruction or a number of instructions, and may be distributed across several different code segments, within different programs, and across multiple storage media. Computer-readable media may include a number of software modules. Software modules include instructions that, when executed by a device such as a processor, cause a processing system to perform various functions. Software modules may include sending modules and receiving modules. Each software module may reside in a single storage device or be distributed across multiple storage devices. For example, when a triggering event occurs, a software module may be loaded from a hard disk drive into RAM. During the execution of a software module, the processor may load some of the instructions into a cache to increase access speed. One or more cache lines may then be loaded into a general-purpose register file for execution by the processor. When the functionality of a software module is referred to below, it will be understood that such functionality is implemented by the processor when executing the instructions from that software module.

[0176] Furthermore, any connection properly referred to as computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (such as infrared (IR), radio, and microwave), then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (such as infrared, radio, and microwave) is included in the definition of medium. As used herein, disk and disc include compressed optical disc (CD), laser disc, optical disc, digital versatile optical disc (DVD), floppy disk, and... Optical discs, where magnetic disks typically copy data magnetically, utilize lasers to optically copy data. Therefore, in some aspects, computer-readable media can include non-transitory computer-readable media (e.g., tangible media). Furthermore, in other aspects, computer-readable media can include transient computer-readable media (e.g., signals). Combinations of the above can also be considered examples of computer-readable media.

[0177] Therefore, certain aspects may include computer program products for performing the operations given herein. For example, such computer program products may include computer-readable media having instructions stored thereon (and / or encoded thereon) that are executable by one or more processors to perform the operations described herein, such as those for performing the operations described herein and in... Figure 8 and / or Figure 9 The instructions for the operation are shown in the figure.

[0178] Furthermore, it should be understood that modules and / or other suitable units for performing the methods and techniques described herein can be downloaded and / or otherwise obtained by the user terminal and / or base station, where applicable. For example, such a device can be coupled to a server to facilitate the transmission of units for performing the methods described herein. Alternatively, the various methods described herein can be provided via storage units (e.g., RAM, ROM, physical storage media such as compressed optical discs (CDs) or floppy disks), such that the user terminal and / or base station can access the various methods when the storage units are coupled to or provided to the device. In addition, any other suitable techniques for providing the methods and techniques described herein to the device can be utilized.

[0179] It should be understood that the claims are not limited to the precise configurations and components shown above. Various modifications, alterations, and variations may be made to the arrangement, operation, and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

1. An apparatus for wireless communication by a first user equipment (UE), comprising: Memory including instructions; as well as One or more processors, individually or in combination, are configured to execute the instructions and cause the device to: The WUS resources for side-link (SL) WUS transmissions from the second UE are determined based on the Wake-up Signal (WUS) resource configuration, wherein the WUS resources correspond to WUS time-frequency resources; A subset of the WUS resources to be monitored is determined based on the broadcast type associated with at least one of the first UE or the second UE. For the subset of WUS resources monitored by the SL WUS from the second UE; and If an SL WUS is detected during the monitoring period, then SL communication with the second UE is initiated.

2. The apparatus according to claim 1, wherein, The first UE is pre-configured with the WUS resource configuration.

3. The apparatus according to claim 1, wherein, The one or more processors are individually or in combination configured to execute the instructions and cause the device to participate in SL communication with the second UE by sending SL transmissions to the second UE.

4. The apparatus according to claim 1, wherein, The one or more processors are individually or in combination configured to execute the instructions and cause the device to participate in SL communication with the second UE by receiving SL transmissions from the second UE.

5. The apparatus according to claim 4, wherein, The one or more processors are configured individually or in combination to execute the instructions and cause the device to also participate in SL communication with the second UE by: Send SL WUS to the second UE; and After sending the SL WUS to the second UE, the SL transmission is sent to the second UE.

6. The apparatus according to claim 1, wherein, The one or more processors are individually or in combination configured to execute the instructions and cause the device to participate in SL communication with the second UE by sending SL transmissions to the second UE without sending SL WUS to the second UE.

7. The apparatus according to claim 1, wherein, The WUS resource configuration indicates WUS resources in at least one of the bandwidth portion (BWP) or SL carrier.

8. The apparatus according to claim 7, wherein: The one or more processors are individually or in combination configured to execute the instructions and cause the device to monitor the SL WUS using a first radio frequency (RF) bandwidth setting based on the BWP or SL carrier; and The one or more processors are individually or in combination configured to execute the instructions and cause the device to participate in SL communication with the second UE using a second RF bandwidth setting that is wider than the first RF bandwidth setting.

9. The apparatus according to claim 1, wherein, The WUS resource configuration indicates the WUS resources in the WUS resource pool shared by multiple UEs.

10. The apparatus according to claim 9, wherein, The WUS resource configuration indicates one or more WUS monitoring opportunities within a time slot for the first UE to perform monitoring.

11. The apparatus according to claim 10, wherein, One or more types of physical SL channels are rate-matched around WUS resources during one or more WUS monitoring times within the time slot.

12. The apparatus according to claim 11, wherein, The format of the time slot provides a gap between at least one WUS monitoring opportunity and the Physical Side Link Shared Channel (PSSCH) in one or more WUS monitoring opportunities.

13. The apparatus according to claim 1, wherein, The one or more processors are configured individually or in combination to execute the instructions and cause the device to: The WUS resource configuration is received from the second UE via broadcast, multicast, or multicast signaling.

14. The apparatus according to claim 13, wherein, The one or more processors are individually or in combination configured to execute the instructions and cause the device to further determine, based on the Layer 2 (L2) identifier (ID) of the second UE, the subset of the WUS resources for monitoring SL WUS transmissions from the second UE.

15. The apparatus according to claim 1, wherein: The subset of WUS resources to be monitored for SL WUS transmissions from the second UE is selected by at least one of the first UE or the second UE during the connection establishment between the first UE and the second UE.

16. The apparatus according to claim 15, wherein, The subset of WUS resources to be monitored for SL WUS transmissions from the second UE is selected based on the identifiers of the first UE and the second UE.

17. The apparatus according to claim 15, wherein: One of the first UE or the second UE indicates a preference for the subset of WUS resources to be used for SL WUS transmissions from the second UE; and The first UE or the second UE, which has not indicated the preference, makes a final decision regarding the subset of WUS resources to be used for SLWUS transmissions from the second UE.

18. The apparatus according to claim 15, wherein, The one or more processors are configured individually or in combination to execute the instructions and cause the device to: Receive network signaling for the subset of WUS resources that indicates monitoring of SL WUS transmissions from the second UE.

19. The apparatus according to claim 1, wherein: The WUS resource configuration is configured jointly with the SL DRX configuration; and The one or more processors are individually or in combination configured to execute the instructions and cause the device to determine the timing of WUS to be monitored based on the SL DRX cycle and SL DRX on duration configured by the SL DRX.

20. The apparatus according to claim 19, wherein, The one or more processors are configured individually or in combination to execute the instructions and cause the device to: During the SL DRX off duration configured in the SL DRX configuration, the subset of WUS resources is monitored for SL WUS from the second UE; as well as The SL DRX remains in a low-power state during the SL DRX on-time of the SL DRX configuration unless an SL WUS is detected during the monitoring period.

21. The apparatus according to claim 1, wherein, The SL WUS is transmitted via at least one of the side link control information (SCI) or a sequence.

22. The apparatus according to claim 21, wherein, The SCI or the sequence indicator includes at least one bit for the wake-up indication and one or more bits indicating at least one of the bandwidth portion (BWP), resource pool, or component carrier (CC) identifier (ID).

23. The apparatus according to claim 21, wherein, The SCI or the sequence is scrambled using at least one of the following: destination ID, group destination ID, or dedicated scrambling ID.

24. The apparatus according to claim 23, wherein, The dedicated scrambling ID is configured for at least one of the first and second UEs used for unicast, for a group of UEs used for managed multicast, or for an application.

25. The apparatus according to claim 1, wherein, The one or more processors are configured individually or in combination to execute the instructions and cause the device to: Provide acknowledgment (ACK) feedback for the SL WUS.

26. The apparatus according to claim 1, wherein, The SL WUS is sent using multiple repetitions within the WUS timeframe.

27. An apparatus for wireless communication by a second user equipment (UE), comprising: Memory including instructions; as well as One or more processors, individually or in combination, are configured to execute the instructions and cause the device to: The WUS resources for side-link (SL) WUS transmission to the first UE are determined based on the Wake-up Signal (WUS) resource configuration, wherein the WUS resources correspond to WUS time-frequency resources; A subset of the WUS resources to be used for the SL WUS transmission is determined based on the broadcast type associated with at least one of the first UE or the second UE. Send SL WUS to the first UE on the determined subset of the WUS resources; and After sending the SL WUS, it participates in SL communication with the first UE.

28. The apparatus according to claim 27, wherein, The WUS resource configuration indicates WUS resources in at least one of the WUS resource pool, bandwidth portion (BWP), or SL carrier shared by multiple UEs.

29. A method for wireless communication by a first user equipment (UE), comprising: The WUS resources for side-link (SL) WUS transmissions from the second UE are determined based on the Wake-up Signal (WUS) resource configuration, wherein the WUS resources correspond to WUS time-frequency resources; A subset of the WUS resources to be monitored is determined based on the broadcast type associated with at least one of the first UE or the second UE. For the subset of WUS resources monitored by the SL WUS from the second UE; and If an SL WUS is detected during the monitoring period, then SL communication with the second UE is initiated.

30. A method for wireless communication by a second user equipment (UE), comprising: The WUS resources for side-link (SL) WUS transmission to the first UE are determined based on the Wake-up Signal (WUS) resource configuration, wherein the WUS resources correspond to WUS time-frequency resources; A subset of the WUS resources to be used for the SL WUS transmission is determined based on the broadcast type associated with at least one of the first UE or the second UE. Send SL WUS to the second UE on the determined subset of the WUS resources; and After sending the SL WUS, it participates in SL communication with the second UE.

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