Drx operation for d2d communication

Abstract

A wireless communication device (UE1) determines a DRX configuration for D2D communication. The DRX configuration is based on at least one timer maintained by the wireless communication device (UE1). Further, the wireless communication device (UE1) controls the at least one timer based on at least one D2D transmission between the wireless communication device (UE1) and another wireless communication device (UE2). Based on the DRX configuration, the wireless communication device (UE1) receives at least one D2D transmission from the other wireless communication device (UE2) (405).

Description

[0001] This application is a divisional application of Chinese invention patent application entitled "DRX operation for D2D communication" (application number 202180058380.2, application date July 29, 2021). Technical Field

[0002] This invention relates to a method for controlling device-to-device (D2D) communication, as well as corresponding devices, systems, and computer programs. Background Technology

[0003] Current wireless communication networks (e.g., based on LTE (Long Term Evolution) or NR technologies as defined by 3GPP (3rd Generation Partnership Project)) also support D2D communication modes to enable direct communication between UEs (User Equipment) (sometimes referred to as secondary link (SL) communication). This D2D communication mode can be used for vehicle-to-everything (V2X) communication, including communication between vehicles, between vehicles and roadside communication infrastructure, and possibly between vehicles and cellular networks. Because it can involve a wide range of different types of devices communicating with vehicles, V2X communication is another term used to refer to this type of communication. Vehicle communication has the potential to improve traffic safety, reduce energy consumption, and enable new services related to intelligent transportation systems.

[0004] Due to the nature of basic road safety services, LTE V2X functionality is designed for broadcast transmissions, i.e., for transmissions in which all receivers within a specific range of a transmitter (i.e., those that can be considered intended recipients) can receive messages from the transmitter. In practice, the transmitter may not be aware of or otherwise unable to control the intended group of receivers. For example, V2X functionality for NR technology is described in 3GPPTR 38.885V16.0.0 (2019-03). In NR technology, more targeted V2X services are also considered by supporting multicast, unicast, or multi-cast transmissions, where the intended recipients of a message are either a subset (multicast) of receivers within a specific range of the transmitter or a single receiver (unicast). For example, in platooning services for vehicles, some messages may only be of interest to member vehicles in the queue, making member vehicles in the queue effectively targets for multicast transmissions. In another example, a see-through function (where one vehicle provides video data from a front-facing camera to subsequent vehicles) may involve V2X communication between only one pair of vehicles, where unicast transmission may be preferred. In addition, NR secondary link communication supports D2D communication between UEs with and without network coverage, where the UE interacts with the network to varying degrees, including the possibility of independent, network-free operation.

[0005] Other potential use cases for D2D communication include NSPS (National Security and Public Safety), Network Control Interaction Services (NCIS), and railway bay analysis. To provide broader NR sidelink coverage for these use cases, further enhancements to NR sidelink technology are being considered. One such enhancement is power saving, which enables battery-constrained UEs to perform sidelink operation in a power-efficient manner. For example, the 3GPP work item “NR Sidelink Enhancement” (document RP-193231, TSG RAN meeting #86, 2019-12) recommends investigating sidelink discontinuous reception (DRX) operation for broadcast, multicast, and unicast transmission modes. It aims to define sidelink DRX configurations and procedures for implementing sidelink DRX in UEs, including mechanisms for aligning sidelink DRX configurations between communicating UEs and mechanisms for aligning sidelink DRX configurations with DRX configurations for downlink (DL) and uplink (UL) communication via the Uu radio interface. However, suitable mechanisms and procedures have not yet been developed.

[0006] For NR technology, 3GPP TS 38.321V16.0.0 (2020-03) specifies the DRX procedures for DL / UL communication via the Uu radio interface. Based on these procedures, the expected UE behavior in the reception and processing of transmissions can be controlled. The underlying DRX functionality is based on defining DRX active time (sometimes referred to as active time states or active states), during which the UE is expected to receive and process incoming transmissions. For example, the UE is expected to decode the DL control channel, process received grants, etc. Outside of DRX active time (during what is also called DRX inactive time), the UE is not expected to receive and process transmissions. Therefore, the access node (denoted as "gNB" in NR technology) cannot assume that the UE will listen for DL ​​transmissions. DRX configuration can also define transitions between states. Typically, UEs not in DRX active time will shut down some of their components and enter a low-power mode (e.g., sleep mode). To ensure that the UE periodically switches to DRX active time (i.e., wakes up from sleep mode), a DRX period is defined. A DRX cycle is essentially based on two parameters: the period of the DRX cycle, which controls how frequently the UE switches to DRX active time; and the duration of the DRX active time, which controls how long the UE remains in DRX active state. In addition to this basic DRX cycle, the DRX procedure defines other conditions that allow the UE to switch between DRX active and DRX inactive times. For example, if the UE is expecting a retransmission from the gNB, the UE can enter a DRX inactive time (e.g., when the gNB is preparing to retransmit), and then enter a DRX active time, which should match the time window in which the gNB is expected to send a retransmission. Typically, the DRX active time of a DRX cycle is determined by the DRX configuration. Therefore, the DRX configuration usually allows prediction of when the UE will be in DRX active time. On the other hand, predicting whether the UE is in DRX active time can be much more difficult due to the various timers that depend on the data traffic the UE is receiving or sending. The DRX procedure specified in 3GPP TS 38.321V16.0.0 applies to DL / UL communication between the UE and the wireless communication network, but not to SL communication or other types of D2D communication.

[0007] Therefore, there is a need for a technology that allows for efficient implementation of DRX for secondary link transmissions and other types of D2D transmissions. Summary of the Invention

[0008] According to one embodiment, a method for controlling D2D communication is provided. According to the method, a wireless communication device determines a DRX configuration for D2D communication. Furthermore, the wireless communication device aligns this DRX configuration with that of another wireless communication device. Based on this DRX configuration, the wireless communication device participates in D2D communication with the other wireless communication device.

[0009] According to another embodiment, a method for controlling D2D communication is provided. According to this method, nodes in a wireless communication network align the first wireless communication device and the second wireless communication device for D2D communication between the first wireless communication device and the second wireless communication device using a DRX configuration.

[0010] According to another embodiment, a method for controlling D2D communication is provided. According to the method, a wireless communication device determines a DRX configuration for D2D communication. This DRX configuration is based on at least one timer maintained by the wireless communication device. Furthermore, the wireless communication device controls the at least one timer based on at least one D2D transmission between itself and another wireless communication device. Based on this DRX configuration, the wireless communication device receives at least one D2D transmission from the other wireless communication device.

[0011] According to another embodiment, a wireless communication device is provided. The wireless communication device is configured to determine a DRX configuration for D2D communication. Furthermore, the wireless communication device is configured to align the DRX configuration with another wireless communication device. Additionally, the wireless communication device is configured to participate in D2D communication with the other wireless communication device based on the DRX configuration.

[0012] According to another embodiment, a wireless communication device is provided. The wireless communication device includes at least one processor and a memory. The memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to determine a DRX configuration for D2D communication. Furthermore, the memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to align the DRX configuration with another wireless communication device. Additionally, the memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to participate in D2D communication with another wireless communication device based on the DRX configuration.

[0013] According to another embodiment, a node for a wireless communication network is provided. The node is configured to align the first and second wireless communication devices for D2D communication between a first wireless communication device and a second wireless communication device using a DRX configuration.

[0014] According to another embodiment, a node for a wireless communication network is provided. The node includes at least one processor and a memory. The memory contains instructions executable by the at least one processor, thereby enabling the node to operate to align the first and second wireless communication devices for a DRX configuration for D2D communication between a first and a second wireless communication device.

[0015] According to another embodiment, a wireless communication device is provided. The wireless communication device is configured to determine a DRX configuration for D2D communication. The DRX configuration is based on at least one timer maintained by the wireless communication device. Furthermore, the wireless communication device is configured to control the at least one timer based on at least one D2D transmission between the wireless communication device and another wireless communication device. Additionally, the wireless communication device is configured to receive at least one D2D transmission from the other wireless communication device based on the DRX configuration.

[0016] According to another embodiment, a wireless communication device is provided. The wireless communication device includes at least one processor and a memory. The memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to determine a DRX configuration for D2D communication. The DRX configuration is based on at least one timer maintained by the wireless communication device. Furthermore, the memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to control the at least one timer based on at least one D2D transmission between the wireless communication device and another wireless communication device. Additionally, the memory contains instructions executable by the at least one processor, thereby enabling the wireless communication device to receive at least one D2D transmission from the other wireless communication device based on the DRX configuration.

[0017] According to another embodiment of the present invention, a computer program or computer program product (e.g., in the form of a non-transitory storage medium) is provided, comprising program code executable by at least one processor of a wireless communication device. Execution of the program code causes the wireless communication device to determine a DRX configuration for D2D communication. Furthermore, execution of the program code causes the wireless communication device to align the DRX configuration with that of another wireless communication device. Additionally, execution of the program code causes the wireless communication device to participate in D2D communication with the other wireless communication device based on the DRX configuration.

[0018] According to another embodiment of the invention, a computer program or computer program product (e.g., in the form of a non-transitory storage medium) is provided, comprising program code to be executed by at least one processor of a node for a wireless communication network. Execution of the program code causes the node to align the first and second wireless communication devices for a DRX configuration for D2D communication between a first and a second wireless communication device.

[0019] According to another embodiment of the present invention, a computer program or computer program product (e.g., in the form of a non-transitory storage medium) is provided, comprising program code executable by at least one processor of a wireless communication device. Execution of the program code causes the wireless communication device to determine a DRX configuration for D2D communication. The DRX configuration is based on at least one timer maintained by the wireless communication device. Furthermore, execution of the program code causes the wireless communication device to control the at least one timer based on at least one D2D transmission between the wireless communication device and another wireless communication device. Additionally, execution of the program code causes the wireless communication device to receive at least one D2D transmission from the other wireless communication device based on the DRX configuration.

[0020] Specific details of such embodiments and further embodiments will become apparent from the following detailed description of the embodiments. Attached Figure Description

[0021] Figure 1 An exemplary V2X scenario with controllable D2D communication is schematically illustrated according to an embodiment of the present invention.

[0022] Figure 2 An exemplary scenario is schematically illustrated according to an embodiment of the present invention, wherein D2D communication can be controlled according to an embodiment of the present invention.

[0023] Figure 3 An exemplary NSPS communication scenario, in which D2D communication can control the establishment of a direct wireless link, is schematically illustrated according to an embodiment of the present invention.

[0024] Figure 4 An exemplary scenario illustrating control of DRX operation for D2D transmission is shown schematically according to an embodiment of the present invention.

[0025] Figure 5 This illustration schematically depicts another exemplary scenario in which DRX operation for D2D transmission is controlled according to an embodiment of the present invention.

[0026] Figure 6 This illustration schematically depicts another exemplary scenario in which DRX operation for D2D transmission is controlled according to an embodiment of the present invention.

[0027] Figure 7 This illustration schematically depicts another exemplary scenario in which DRX operation for D2D transmission is controlled according to an embodiment of the present invention.

[0028] Figure 8A An exemplary scenario of an aligned DRX configuration is schematically illustrated according to an embodiment of the present invention.

[0029] Figure 8B This illustration schematically depicts another exemplary scenario of an aligned DRX configuration according to an embodiment of the present invention.

[0030] Figure 9A This illustration schematically depicts another exemplary scenario of an aligned DRX configuration according to an embodiment of the present invention.

[0031] Figure 9B This illustration schematically depicts another exemplary scenario of an aligned DRX configuration according to an embodiment of the present invention.

[0032] Figure 10 This illustration schematically depicts another exemplary scenario of an aligned DRX configuration according to an embodiment of the present invention.

[0033] Figure 11 This illustration schematically depicts another exemplary scenario of an aligned DRX configuration according to an embodiment of the present invention.

[0034] Figure 12 A flowchart illustrating a method according to an embodiment of the present invention is shown.

[0035] Figure 13 The diagram illustrates the implementation corresponding to Figure 12 An exemplary block diagram illustrating the functionality of a wireless communication device.

[0036] Figure 14 A flowchart illustrating another method according to an embodiment of the present invention is shown.

[0037] Figure 15 The diagram illustrates the implementation corresponding to Figure 14 An exemplary block diagram illustrating the functionality of a wireless communication device.

[0038] Figure 16 A flowchart illustrating another method according to an embodiment of the present invention is shown.

[0039] Figure 17 The diagram illustrates the implementation corresponding to Figure 16 An exemplary block diagram illustrating the functionality of a network node in the method.

[0040] Figure 18The diagram schematically illustrates the structure of a wireless communication device according to an embodiment of the present invention.

[0041] Figure 19 The diagram schematically illustrates the structure of a network node according to an embodiment of the present invention. Detailed Implementation

[0042] In the following, the concepts of exemplary embodiments according to the present invention will be described in more detail with reference to the accompanying drawings. The illustrated embodiments relate to the control of D2D communication by wireless communication devices. These wireless communication devices may include various types of UEs or other wireless devices (WDs). As used herein, the term "wireless device" (WD) means a device capable of, configured, set up, and / or operable to wirelessly communicate with network nodes and / or other WDs. Unless otherwise stated, the term WD may be used interchangeably with UE herein. Wireless communication may involve transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for transmitting information over the air. In some embodiments, a WD may be configured to transmit and / or receive information without direct human interaction. For example, a WD may be designed to send information to the network at a predetermined schedule when triggered by internal or external events or in response to a request from the network. Examples of WDs include, but are not limited to, smartphones, mobile phones, cellular phones, Voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, game consoles or devices, music storage devices, playback devices, wearable terminal devices, wireless endpoints, mobile stations, tablet computers, laptop computers, laptop embedded devices (LEEs), laptop mounted devices (LMEs), smart devices, wireless client devices (CPEs), in-vehicle wireless terminal devices, connected vehicles, etc. In some examples, in Internet of Things (IoT) scenarios, a WD can also represent a machine or other device that performs monitoring and / or measurement and sends the results of such monitoring and / or measurement to another WD and / or network node. In this case, the WD can be a machine-to-machine (M2M) device, which in the 3GPP context can be referred to as a machine-type communication (MTC) device. As a specific example, a WD can be a UE implementing the 3GPP Narrowband Internet of Things (NB-IoT) standard. Specific examples of such machines or devices are sensors, metering devices (such as power meters), industrial machinery, or household or personal appliances (e.g., refrigerators, televisions, etc.), or personal wearable devices (e.g., watches, fitness trackers, etc.). In other scenarios, a WD can refer to a vehicle or other device capable of monitoring and / or reporting its operational status or other functions associated with its operation. A WD as described above can refer to a wirelessly connected endpoint, in which case the device may be referred to as a wireless terminal. Furthermore, a WD as described above can be mobile, in which case it may also be referred to as a mobile device or mobile terminal. The concepts illustrated specifically relate to WDs supporting D2D communication, for example, by implementing 3GPP standards for secondary link communication, vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-everything (V2X).D2D communication can be based, for example, on LTE or NR radio technologies as defined by 3GPP, such as on the PC5 interface of LTE or NR technologies. However, note that the concepts described can also be applied to other radio technologies, such as WLAN (Wireless Local Area Network) technology.

[0043] In the concepts described, D2D communication can be performed in a power-efficient manner using procedures and mechanisms that enable DRX operations for D2D communication. DRX operations can be applied to secondary link (SL) communication, for example, via the PC5 interface of LTE or NR technologies, and are denoted herein as "SL DRX". DRX operations may involve configuring DRX active and inactive times for the UE participating in D2D communication. A sequence of active and subsequent inactive times can also be denoted as a "SL DRX cycle". Note that SL DRX cycles do not need to repeat periodically, and the duration of active and / or inactive times can vary from one SL DRX cycle to the next.

[0044] In the D2D communication considered herein, the UE can act as a receiver (also referred to herein as the RX UE) and / or a transmitter (also referred to herein as the TX UE). For the TX UE, participating in D2D communication may involve the TX UE sending at least one D2D transmission to the RX UE during DRX active time. For the RX UE, participating in D2D communication may involve the RX UE receiving at least one D2D transmission from the TX UE during DRX active time. During DRX inactive time, the RX UE may shut down at least a portion of its receiver circuitry to achieve power savings. During DRX active time, the RX UE is in DRX active mode and is not permitted to shut down portions of its receiver circuitry. The TX UE can consider DRX inactive time by avoiding sending any D2D transmissions to the RX UE during DRX inactive time.

[0045] Note that some of the examples below are described from the perspective of the RX UE, while others are described from the perspective of the TX UE; however, the roles of RX UE and TX UE are interchangeable. Furthermore, a UE can act as both a TX UE and an RX UE simultaneously. Additionally, while the examples described below assume that the D2D UE and its serving access node operate using the same Radio Access Technology (RAT) (e.g., NR or LTE), the concepts illustrated can be applied to any combination of RATs between the D2D UE and its serving access node. Furthermore, in the illustrated concepts, D2D transmission can be based on unicast, multicast, or broadcast transmission modes.

[0046] Figure 1 The illustration depicts an exemplary scenario involving V2X communication. Specifically, Figure 1 Various UE 10 models are shown, which can participate in V2X communication or other D2D communication, as indicated by solid arrows. Furthermore, Figure 1 An access node 100 of a wireless communication network is shown, such as an eNB with LTE technology, a gNB with NR technology, or an access point for a WLAN. At least some UEs 10 may also be able to communicate using DL radio transmissions and / or UL radio transmissions, as indicated by the dashed arrows.

[0047] Figure 1 The UE 10 shown includes vehicles, drones, mobile phones, and people, such as pedestrians, cyclists, vehicle drivers, or vehicle passengers. Note that in the case of a vehicle, radio transmissions can be performed by a communication module installed in the vehicle, while in the case of a person, radio transmissions can be performed by a wireless device carried or worn by the person (e.g., a wristband device or similar wearable device). Furthermore, note that... Figure 1 The UE shown is merely exemplary, and other types of V2X or D2D communication devices may also be used within the illustrated concepts, such as RSUs (Roadside Units) or other infrastructure-based V2X communication devices, V2X communication devices located in aircraft (such as airplanes or helicopters), spacecraft, trains or train carriages, ships, motorcycles, bicycles, motorized scooters, or any other type of mobile or transport equipment. V2X communication may also involve using the illustrated mechanisms and processes to enable DRX operation for V2X communication between UEs 10, thereby improving the energy efficiency of V2X communication.

[0048] Figure 2 An exemplary D2D communication scenario is illustrated. Specifically, Figure 2 Multiple UEs 10 are shown, interconnected by radio links implementing direct radio links (indicated by double-headed arrows). Furthermore, one of the UEs 10 is connected via a radio link to an access node 100 of the wireless communication network, for example, to an eNB using LTE technology or a gNB using NR technology. Access node 100 is part of the RAN (Radio Access Network) of the wireless communication network, which typically also includes other access nodes to provide the desired coverage of the wireless communication network. Furthermore, Figure 2 The core network (CN) 210 of the wireless communication network is shown. CN 210 can provide the UE 10 with connectivity to other data networks, for example, through GW 220 provided in CN 210. In addition, CN 210 may also include various nodes for controlling the operation of UE 10.

[0049] Radio links can be used for D2D communication between UEs 10. Furthermore, radio links to wireless communication networks can be used for control or other facilitators of D2D communication. Additionally, D2D communication and / or data communication with wireless communication networks can be used to provide various services to UEs 10, such as voice services, multimedia services, data services, Intelligent Transportation Systems (ITS) or similar vehicle management or coordination services, NSPS services, and / or NCIS services. These services can be based on applications executed on UEs 10 and / or on devices linked to UEs 10. Therefore, in the illustrated concepts, D2D transmissions can transmit or correspond to V2X messages, ITS messages, or some other type of service-related message. Furthermore, Figure 2 The illustration shows the application service platform 250 within the CN 210 wireless communication network. Furthermore, Figure 2 The illustration shows one or more application servers 300 provided outside the wireless communication network. Applications running on UE 10 and / or one or more other devices linked to UE 10 can use radio links with one or more other UE 10s, application service platform 250, and / or application server 300 to enable corresponding services on UE 10. In some scenarios, the services used by UE 10 can therefore be hosted on the network side, for example, on application service platform 250 or application server 300. However, some services can also be network-independent, allowing them to be used without an active data connection to the wireless communication network. This can be applied, for example, to certain V2X or NSPS services. However, when UE 10 is within the coverage area of ​​the wireless communication network, such services can still be assisted from the network side. Similarly, Figure 2 In such scenarios, UE 10 can apply DRX operations to D2D communication to improve energy efficiency.

[0050] exist Figure 2 In the example, it is assumed that UE 10 is a mobile phone and vehicle-based or vehicle-integrated communication device (e.g., an in-vehicle or vehicle-integrated communication module), or a smartphone or other user equipment linked to a vehicle system. However, note that other types of UEs can also be used, such as pedestrian-carried devices or infrastructure-based devices, such as... Figure 1 The roadside unit shown.

[0051] Figure 3 A schematic illustration of an NSPS communication scenario is provided. Specifically, Figure 3Multiple UEs 10 are illustrated, which can exchange NSPS messages associated with one or more NSPS services using D2D communication, for example, based on LTE secondary link communication or NR secondary link communication. As further shown, NSPS services can be assisted from the network by exchanging NSPS messages via access node 100. NSPS services may include, for example, group communication of other devices or personnel from rescue vehicles, rescue personnel, or public safety-related organizations. Such communication may also involve using the illustrated mechanisms and processes to enable DRX operation for D2D communication between UEs 10, thereby improving the energy efficiency of D2D communication.

[0052] As mentioned above, in some scenarios, D2D communication applying DRX operation can be based on SL mode using NR or LTE technology and employing the PC5 radio interface. In this case, SL communication can be based on multiple physical channels defined at the physical (PHY) layer of the radio interface between the TX UE and the RX UE, including the Physical Secondary Link Control Channel (PSCCH), Physical Secondary Link Shared Channel (PSSCH), Physical Secondary Link Feedback Channel (PSFCH), and Physical Secondary Link Broadcast Channel (PSBCH). Data decoded from the PHY layer can then be further processed by the RX UE's MAC (Media Access Control) entity.

[0053] The PSCCH carries only control information, often referred to as Phase 1 SCI (Secondary Link Control Message). It is transmitted using a predefined format on predetermined radio resources, allowing the RX UE to perform blind decoding. That is, the RX UE attempts to decode the PSCCH according to the predefined format on predetermined radio resources without knowing beforehand whether the PSCCH has actually been transmitted. If the decoding operation is successful, the RX UE assumes the PSCCH was transmitted. Otherwise, it assumes the PSCCH was not transmitted. The PSCCH carries the information necessary for decoding.

[0054] The PSSCH carries both control information and a data payload. The control information is often referred to as the second-stage SCI. It is transmitted using the radio resource allocation and transmission format indicated in the PSSCH. It also contains other information necessary for decoding the data payload carried by the PSSCH.

[0055] The PSFCH carries only feedback information. The content of the PSFCH depends on the HARQ operation mode. In some cases, both positive (also labeled ACK) and negative (also labeled NACK) acknowledgments are sent. In other cases, only NACK is sent. PSFCH transmissions use a predefined format and occur within predetermined radio resources.

[0056] The PSBCH carries basic system configuration information, such as bandwidth and TDD (Time Division Duplex) configuration. In addition, the PSBCH carries synchronization signals.

[0057] For SL communication, a typical operation can be as follows: A first UE performs SL transmission on the PSCCH and PSSCH. A second UE receives the SL transmission. Receiving the SL transmission may involve, with the aid of blind decoding, the second UE detecting the PSCCH and decoding the first-stage SCI carried by the PSCCH. If blind decoding is successful, the second UE uses the decoded content of the PSCCH to decode the second-stage SCI carried by the PSSCH. After decoding the second-stage SCI, the second UE uses the first-stage SCI and the second-stage SCI to decode the payload data carried by the PSSCH. After successfully decoding the payload data, the second UE continues to send HARQ (Hybrid Automatic Repeat Request) feedback on the PSFCH. Different modes of providing HARQ feedback can be used. The first UE expects to receive HARQ feedback from the second UE and can use the presence and content of the PSFCH to determine further actions, such as whether to perform a retransmission. Therefore, the PSDCH can be used to trigger actions related to HARQ operations for SL transmission. In some cases, the use of HARQ feedback can also be omitted. For example, HARQ feedback is generally not used for SL transmissions in broadcast mode. The TX UE (e.g., the first UE in the considered example) can indicate in the SCI whether it expects the RX UE (e.g., the second UE in the considered example) to send a PSFCH with HARQ feedback.

[0058] DRX operations for SL transmissions can be based on one or more timers and parameters (as part of the UE's SL DRX configuration) to control the UE's handover between active and inactive times. Specifically, these timers and parameters may include one or more of the following:

[0059] The timer labeled "drx-onDurationTimerSL" is defined as the duration at the start of the SL DRX cycle;

[0060] The parameter labeled "drx-SlotOffsetSL" defines the delay before starting the timer drx-onDurationTimerSL;

[0061] The parameter labeled "drx-LongCycleStartOffsetSL" defines the long SL DRX cycle;

[0062] The parameter labeled "drx-StartOffsetSL" is defined in the subframe at the start of the (long or short) SL DRX cycle;

[0063] The optional parameter labeled "drx-ShortCycleSL" defines the short SL DRX cycle;

[0064] An optional timer labeled “drx-ShortCycleTimerSL” indicates that the UE should follow the duration of the short SL DRX cycle;

[0065] The timer, designated “drx-InactivityTimerSL”, is defined as the duration following the receipt of a PSCCH / PSSCH timing event that includes SCI information indicating a new SL transmission for the MAC entity.

[0066] The timer labeled "drx-RetransmissionTimerSL" is defined as the maximum duration until an SL retransmission is received, and is typically defined per SL HARQ process, except for broadcast SL transmissions;

[0067] The timer labeled “drx-HARQ-RTT-TimerSL” is defined as the minimum duration prior to the SL retransmission authorization for SL HARQ retransmission expected by the MAC entity on the PSCCH, and is typically defined per SL HARQ process, except for broadcast SL transmissions.

[0068] The timer labeled "drx-HARQ-FB-TimerSL" is defined as the maximum duration until SL HARQ feedback is received, and is typically defined per SL HARQ process, except for broadcast SL transmissions;

[0069] The timer labeled “drx-HARQ-FB-RTT-TimerSL” is defined as the minimum duration expected before the SL HARQ feedback on the PSFCH after the associated PSSCH transmission if a given PSSCH transmission requires HARQ feedback. It is typically defined per SL HARQ process, except for broadcast SL transmissions.

[0070] The timer labeled "drx-CSIReport-TimerSL" is defined as the maximum duration until an SL CSI (Channel State Information) report is received;

[0071] The timer labeled “drx-CSIReport-RTT-TimerSL” is defined as the minimum duration prior to the MAC entity’s expected authorization of the SL transmission for CSI reporting on the PSCCH.

[0072] The timer labeled "drx-Retx-Proc-TimerSL" is defined as the minimum duration expected before the next blind retransmission, typically defined per SL HARQ procedure;

[0073] The timer labeled “drx-BlindRetransmissionTimerSL” is defined as the maximum duration until the next blind retransmission is received, or alternatively, the maximum duration until all blind retransmissions of the SL transmission are received, or the maximum number of blind retransmissions for the SL transmission, typically defined per SL process.

[0074] Because of their use in controlling SL DRX operation, the timers mentioned above can also be called "SL DRX timers". Note that the names of the timers and parameters above can change, and the SL DRX configuration can also include various additional parameters.

[0075] Note that the concepts described herein can be used by applying all or only a subset of the parameters and timers defined in the SL DRX configuration. For example, in some cases, only a subset of all parameters or timers may be configured or enabled. For instance, the SL DRX configuration may include parameters or timers related to HARQ, but some of these parameters or timers may not be used if HARQ feedback is not used or disabled. Similarly, some parameters or timers may not be used if the maximum number of data packet transmissions is set to one or its usage is limited based on the configured maximum number of retransmissions. For example, a timer may be reset only K times for a data packet, where K is the maximum number of transmissions for that data packet or the (pre)configured maximum number of transmissions, for example, (pre)configured per SL resource pool. Similarly, some parameters or timers may not be used if the SL transmission has no associated SL HARQ feedback, or if the grant or SL resource pool does not include resources for sending SL HARQ feedback.

[0076] As further explained below, considering SL transmission characteristics such as anticipated HARQ feedback transmissions, data (re)transmissions, and / or CSI report transmissions, UEs participating in SL transmissions can be configured to wake up during DRX operation, i.e., switch to DRX active time. Therefore, the DRX timer can be controlled (i.e., started, restarted, or stopped) based on one or more SL transmissions. These SL transmissions may include, for example, SL transmissions carrying control information in the PSCCH or PSSCH. Alternatively or additionally, these SL transmissions may include, for example, SL transmissions carrying a data payload in the PSSCH. Alternatively or additionally, these SL transmissions may include, for example, SL transmissions carrying feedback in the PSFCH. Alternatively or additionally, these SL transmissions may include, for example, SL transmissions triggering CSI reporting by indicating it in the SCI, by carrying CSI-RS, etc. Alternatively or additionally, these SL transmissions may include SL transmissions carrying CSI reports (e.g., including rank indicators (RI), channel quality indicators (CQI), precoding matrix indicators (PMI), or transmissions carrying SL path loss estimates), for example, for power control.

[0077] The SL DRX timers include timers that keep the UE in DRX active mode while the timer is running, as well as other timers, such as timers that control the time during which the UE is allowed to leave DRX active mode. In the following examples, the UE is controlled to be in DRX active mode when any of the following timers (which may also be labeled "DRX active timers") are running: timer drx-onDurationTimerSL, timer drx-InactivityTimerSL, timer drx-RetransmissionTimerSL, timer drx-HARQ-FB-TimerSL, timer drx-CSIReport-TimerSL, and timer drx-BlindRetransmissionTimerSL. In some scenarios, it may be possible that the UE does not need to be in DRX active mode continuously while timer drx-BlindRetransmissionTimerSL is running.

[0078] In some examples, after the UE receives an SCI (indicating an SL transmission of interest, to which the UE is the receiving target) carried in, for example, the PSCCH or PSSCH, or sends a trigger message (e.g., a message triggering an SL CSI report that triggers an SL transmission from another UE), the UE starts the timer drx-InactivityTimerSL. When the timer drx-InactivityTimerSL expires, if a short SL DRX period is configured, the UE uses that short SL DRX period and starts or restarts the timer drx-ShortCycleTimerSL; otherwise, it uses a long SL DRX period. In other examples, if the data for the corresponding HARQ procedure is successfully decoded, the UE stops all DRX active timers, such as the timer drx-onDurationTimerSL, the timer drx-InactivityTimerSL, the timer drx-RetransmissionTimerSL, and the optional timer drx-BlindRetransmissionTimerSL.

[0079] In some scenarios, the concepts described can be used to enable DRX operations for retransmissions based on HARQ feedback. In such scenarios, if an SCI carried, for example in the PSCCH or PSSCH, indicates that an associated PSSCH transmission requires HARQ feedback, the UE starts a timer drx-HARQ-RTT-TimerSL in the first symbol after the end of the corresponding transmission carrying SL HARQ feedback. Additionally, for the corresponding SL HARQ procedure, the UE stops timer drx-RetransmissionTimerSL. If timer drx-HARQ-RTT-TimerSL expires and the data for the corresponding SL HARQ procedure is not successfully decoded, the UE starts timer drx-RetransmissionTimerSL for the corresponding SL HARQ procedure. While timer drx-RetransmissionTimerSL is running, the UE remains in DRX active mode. If the UE decodes a retransmission for the corresponding SL HARQ procedure while an associated DRX active timer is running (e.g., while timer drx-RetransmissionTimerSL is running), the UE can stop that DRX active timer.

[0080] Figure 4 An example of the procedure for enabling DRX operation for HARQ-based retransmission is shown. Figure 4 The process involves a first UE (UE1) and a second UE (UE2). In Figure 4 In the example, UE 1 receives, for example, an SL transmission 401 carrying a MAC PDU (Protocol Data Unit), which requires HARQ feedback. The requirement for HARQ feedback can be indicated by the SCI associated with SL transmission 401. As further shown, UE 1 sends HARQ feedback 402 to UE 2. As shown in box 403, UE 1 then starts a timer drx-HARQ-RTT-TimerSL for the corresponding HARQ procedure and stops a timer drx-RetransmissionTimerSL for the corresponding HARQ procedure. This can be done in the first symbol after the corresponding SL transmission carrying SL HARQ feedback 402 has ended. As shown in box 404, when timer drx-HARQ-RTT-TimerSL expires and the data for the corresponding HARQ procedure has not been successfully decoded, UE 1 starts a timer drx-RetransmissionTimerSL for the corresponding HARQ procedure. This can be done in the first symbol after drx-HARQ-RTT-TimerSL expires. During the subsequent DRX activity period, UE 1 receives a retransmission 405 from UE 2 based on HARQ feedback. As shown in box 406, after successfully decoding data from the corresponding HARQ procedure, for example based on the initial SL transmission 401 and the retransmission 405, UE 1 stops the timer drx-RetransmissionTimerSL, which allows UE 1 to leave DRX activity mode.

[0081] In some scenarios, the concepts described can be used to enable DRX operation for HARQ feedback transmissions. In such scenarios, the UE can send SCIs, for example, carried in the PSCCH or PSSCH, indicating that the associated PSSCH transmission requires HARQ feedback and that the UE expects to receive HARQ feedback from its peer. The UE can then start a timer drx-HARQ-FB-RTT-TimerSL for the corresponding HARQ procedure in the first symbol after the end of the corresponding PSSCH transmission. After timer drx-HARQ-FB-RTT-TimerSL expires, the UE starts another timer drx-HARQ-FB-TimerSL for the corresponding HARQ procedure. While timer drx-HARQ-FB-TimerSL is running, the UE remains in DRX active mode to enable the reception of the expected HARQ feedback. If the expected HARQ feedback is received, the UE can stop timer drx-HARQ-FB-TimerSL.

[0082] During the above process, timers drx-HARQ-RTT-TimerSL and drx-RetransmissionTimerSL can be selectively applied or not applied depending on the scheduling mode associated with the HARQ procedure. For example, if the HARQ procedure is based on SL granting configured in Mode 1, the UE can avoid applying timers drx-HARQ-RTT-TimerSL and drx-RetransmissionTimerSL. In this way, it can be assumed that SL HARQ feedback will not trigger retransmission for SL granting configured in Mode 1. The selective application of timers can be based on, for example, indicating the scheduling mode to the receiving UE in the PSCCH. This indication can be explicitly included in the SCI or can be implicitly obtained from other information indicated on the PSCCH. When using selective application of timers, the configuration of timers drx-HARQ-RTT-TimerSL and drx-RetransmissionTimerSL can differ from the case where timers are applied non-selectively.

[0083] Figure 5 An example of the procedure for enabling DRX operation for HARQ feedback is shown. Figure 5 The process involves a first UE (UE1) and a second UE (UE2). In Figure 4 In the example, UE 1 sends an SL transmission 501, for example, carrying a MAC PDU, to UE 2. The SL transmission 501 may be sent based on an SL grant requiring HARQ feedback, for example. Therefore, as shown in box 502, UE 1 starts a timer drx-HARQ-FB-RTT-TimerSL for the corresponding HARQ procedure. This can be done in the first symbol after the corresponding PSSCH transmission (i.e., SL transmission 501) ends. As shown in box 503, when the timer drx-HARQ-FB-RTT-TimerSL expires, UE 1 starts a timer drx-HARQ-FB-TimerSL for the corresponding HARQ procedure. This can be done in the first symbol after the timer drx-HARQ-RTT-TimerSL expires. During the subsequent DRX activity period, UE 1 receives HARQ feedback 504 from UE 2 for the SL transmission 501. As shown in box 505, after receiving HARQ feedback 504, UE1 can stop the timer drx-HARQ-FB-TimerSL used for the corresponding HARQ procedure.

[0084] In the above process, the configuration of the timer drx-HARQ-FB-RTT-TimerSL (i.e., the duration until the timer expires) can be based at least on the UE (i.e., Figure 5The processing capability of UE2 in the example is determined by the expected HARQ feedback. Furthermore, the configuration of timer drx-HARQ-FB-RTT-TimerSL can be determined based on the time-domain periodicity of the PSFCH resources on the relevant resource pool (which are used for the transmission of expected HARQ feedback).

[0085] In some scenarios, the concepts described can be used to enable DRX operation for blind retransmissions (which are not triggered by HARQ feedback). In such scenarios, the UE may receive an SCI, for example, carried by the PSCCH or PSSCH, indicating that no HARQ feedback is expected for the associated SL transmission (e.g., a transport block carried by the PSSCH). In this case, the UE can, however, expect to receive blind retransmissions in the future. For example, the SCI may indicate the time and / or frequency resources in which blind retransmissions can be expected. In this case, the UE may start a timer drx-Retx-Proc-TimerSL for the corresponding SL procedure in the first symbol after receiving the corresponding PSSCH transmission and stop a timer drx-BlindRetransmissionTimerSL for the corresponding SL procedure. After drx-Retx-Proc-TimerSL expires and if the data for the corresponding SL procedure has not been successfully decoded, the UE may start a timer drx-BlindRetransmissionTimerSL. While timer drx-BlindRetransmissionTimerSL is running, the UE remains in DRX active mode to enable expected blind retransmission reception. If the UE successfully decodes the blind retransmission for the corresponding SL procedure while the associated timer drx-BlindRetransmissionTimerSL is running, the UE can stop timer drx-BlindRetransmissionTimerSL.

[0086] Figure 6 An example of the procedure for enabling DRX operation for blind retransmission is shown. Figure 6 The process involves a first UE (UE1) and a second UE (UE2). In Figure 6In the example, UE 1 receives, for example, an SL transmission 601 carrying a MAC PDU, which does not require HARQ feedback. The requirement for HARQ feedback can be indicated by the SCI associated with SL transmission 601. As shown in box 602, upon receiving SL transmission 601, UE 1 starts drx-Retx-Proc-TimerSL for the corresponding SL procedure and stops drx-BlindRetransmissionTimerSL for the corresponding SL procedure. This can be done in the first symbol after the end of receiving the corresponding PSSCH (i.e., SL transmission 601). As shown in box 603, when timer drx-Retx-Proc-TimerSL expires and the data for the corresponding SL procedure is not successfully decoded, UE 1 starts timer drx-BlindRetransmissionTimerSL for the corresponding SL procedure. This can be done in the first symbol after timer drx-Retx-Proc-TimerSL expires. During subsequent DRX activity time, UE 1 receives blind retransmission 604 from UE 2. As shown in box 605, after successfully decoding data from the corresponding SL procedure, for example based on the initial SL transmission 601 and blind retransmission 605, UE 1 stops the timer drx-BlindRetransmissionTimerSL, which allows UE 1 to leave DRX active mode.

[0087] In the above process, the configuration of the timer drx-Retx-Proc-TimerSL (i.e., the duration until the timer expires) can be given by the time gap between the two reservations on the PSSCH. This time gap between the two reservations can be indicated in the PSSCH, for example, using the information field of the SCI labeled "Time Resource Allocation".

[0088] In another variation of the above process, the UE can also immediately initiate drx-BlindRetransmissionTimerSL in response to receiving an SL transmission that does not require HARQ feedback, for example, in the Nth symbol after receiving the corresponding PSSCH. Therefore, the initiation of timer drx-BlindRetransmissionTimerSL can also be triggered without using timer drx-Retx-Proc-TimerSL. The value of N can be based on the UE (i.e., Figure 6 The example UE2) provides blind retransmission processing capabilities to determine this. In some scenarios, the value of N can be N=1.

[0089] In both variations of the above process, the configuration of timer drx-BlindRetransmissionTimerSL (i.e., the duration until the timer expires) can be defined in terms of the number of consecutive SCIs (e.g., those carried by PSCCH or PSSCH indicating blind retransmissions of the same transport block in the SL process). Furthermore, the configuration of timer drx-BlindRetransmissionTimerSL (i.e., the duration until the timer expires) can be defined as the maximum duration corresponding to the period until all blind retransmissions of the transport block are received or the maximum number of blind retransmissions is reached. For example, if the UE receives an SL transmission that does not require HARQ feedback, the UE can, for example, start timer drx-Retx-Proc-TimerSL for the corresponding SL process in the first symbol after the end of receiving the corresponding PSSCH, and pause drx-BlindRetransmissionTimerSL if it has already been started. When timer drx-Retx-Proc-TimerSL expires, the data for the corresponding SL procedure is not successfully decoded, and timer drx-BlindRetransmissionTimerSL has not yet been started, the UE can, for example, start timer drx-BlindRetransmissionTimerSL for the corresponding SL procedure in the first symbol after drx-Retx-Proc-TimerSL expires. If timer drx-BlindRetransmissionTimerSL has been started but has not yet expired, the UE can, for example, resume timer drx-BlindRetransmissionTimerSL for the corresponding SL procedure in the first symbol after drx-Retx-Proc-TimerSL expires. If the data for the corresponding SL procedure is successfully decoded, the UE does not need to be activated / wake up, even if drx-BlindRetransmissionTimerSL for the corresponding SL procedure may still be running.

[0090] In some scenarios, the concepts described can be used to enable DRX operation for transmissions related to CSI reports. In such a scenario, it is assumed that the PSSCH sent by the UE may include a reference signal that triggers a CSI report from the peer UE. Alternatively or additionally, the PSCCH sent by the UE may include a CSI report request. Therefore, the UE can expect to receive a CSI report from the peer UE. Furthermore, the UE can start a timer drx-CSIReport-RTT-TimerSL, for example, in the first symbol after sending the corresponding PSSCH or after the PSCCH ends. After the timer drx-CSIReport-RTT-TimerSL expires, the UE can start a timer drx-CSIReport-TimerSL. While the timer drx-CSIReport-TimerSL is running, the UE remains in DRX active mode to enable the reception of the expected CSI report. If the corresponding CSI report is received, the UE can stop the timer drx-CSIReport-TimerSL.

[0091] Figure 7 An example of the procedure for enabling DRX operation for CSI reporting is shown. Figure 7 The process involves a first UE (UE1) and a second UE (UE2). In Figure 7 In the example, UE 1 sends, for example, an SL transmission 701 carrying a MAC PDU (which triggers a CSI report from UE 2). The SL transmission 701 may be sent based on an SL grant and include a reference signal and / or a request for a CSI report. As shown in box 702, after sending the SL transmission 701, UE 1 starts the drx-CSIReport-RTT-TimerSL for the corresponding HARQ procedure and stops the timer drx-CSIReport-TimerSL for the corresponding SL procedure. This can be done in the first symbol after the corresponding PSSCH or PSCCH transmission (i.e., SL transmission 701) ends. As shown in box 703, when the timer drx-CSIReport-RTT-TimerSL expires, UE 1 starts the timer drx-CSIReport-TimerSL for the corresponding HARQ procedure. This can be done in the first symbol after the timer drx-HARQ-RTT-TimerSL expires. During the subsequent DRX activity period, UE 1 receives a CSI report 704 from UE 2. As shown in box 705, after successfully receiving CSI report 704, UE 1 stops the timer drx-CSIReport-TimerSL used for the corresponding HARQ procedure, which allows UE 1 to leave DRX active mode.

[0092] Given that DRX is to be used effectively for SL communication and other types of D2D communication, it may be necessary to align the SL DRX configuration (particularly timers and / or parameters for controlling the transition between DRX active and DRX inactive times) between peer UEs participating in D2D communication. Furthermore, it may be necessary to align the UE's SL DRX configuration with its DRX configuration used for DL / UL communication with the wireless communication network (also referred to hereinafter as DL / UL DRX configuration, or simply as DL DRX configuration in relation to DRX operations related to receiving DL transmissions). In this way, the duration in which the UE is in DRX active time can be minimized. As used herein, the SL DRX configuration may denote a set of one or more parameters that determine the UE's DRX behavior in SL communication, for example, including the settings of the timers and other parameters mentioned above.

[0093] The following describes the procedures and mechanisms that allow for the alignment of SL DRX configurations among peer UEs participating in SL communication. In these descriptions, it will be assumed that SL communication is based on a unicast transmission mode. However, note that the principles of aligning SL DRX configurations described can also be applied to groups of UEs participating in SL communication based on multicast or broadcast transmission modes. Some of these procedures and mechanisms involve one or more access nodes of the wireless communication network. Similar to access node 100 mentioned above, these access nodes may correspond to a gNB for NR technology or an eNB for LTE technology.

[0094] Alignment in the SL DRX configuration can be based on the following variations:

[0095] -According to the first variant, the RX UE or the RX UE's serving access node provides the SL DRX configuration for the RX UE and coordinates the SL DRX configuration with the TX UE or the TX UE's serving access node, for example, by indicating the corresponding configuration information to the TX UE and / or its serving access node.

[0096] - According to the second variant, the TX UE or the TX UE's serving access node provides the SL DRX configuration for the RX UE and coordinates the SL DRX configuration with the RX UE or the RX UE's serving access node, for example, by indicating the corresponding configuration information to the TX UE and / or its serving access node.

[0097] According to the third variant, the access node performs alignment between the DL / UL DRX configuration and the SL DRX configuration. Furthermore, the access node can indicate either the DL / UL DRX configuration or the SL DRX configuration to the UE. For example, the access node can indicate the DL / UL DRX configuration and the deviation between the DL / UL DRX configuration and the SL DRX configuration. Alternatively, the access node can indicate the SL DRX configuration and the deviation between the SL DRX configuration and the DL / UL DRX configuration. This deviation can be indicated in terms of one or more incremental values ​​between corresponding parameters of the DL / UL DRX configuration and the SL DRX configuration.

[0098] According to the fourth variant, the TX UE indicates its DL / UL DRX configuration and / or SL DRX configuration to the RX UE, and the RX UE then considers the indicated DRX configuration when determining the RX UE's DL / UL DRX configuration and / or SL DRX configuration. Alternatively, the RX UE indicates its DL / UL DRX configuration and / or SL DRX configuration to the TX UE, and the TX UE then considers the indicated DRX configuration when determining the TX UE's DL / UL DRX configuration and / or SL DRX configuration.

[0099] Figure 8A An example of the process for aligning SL DRX configurations by exchanging configuration information between the RX UE and the TX UE is shown. Specifically, in Figure 8A In the example, the RX UE determines its SLDRX configuration and indicates the determined SLDRX configuration to the TX UE. Figure 8A The process involves the RX UE, the TX UE, the access node (AN1) serving the RX UE, and the access node (AN2) serving the TX UE. Note that in some scenarios, the RX UE and the TX UE may also be served by the same access node.

[0100] exist Figure 8A During this process, the access node AN1 can send configuration information (CI) 801 to the RX UE. Configuration information 801 may, for example, indicate the RX UE's DL / UL DRX configuration and / or parameters that the RX UE will use to determine its SL DRX configuration. In some scenarios, the access node AN1 can also determine the SL DRX configuration for the RX UE and use configuration information 801 to indicate the SL DRX configuration to the RX UE.

[0101] Then, the RX UE determines its SL DRX configuration and sends configuration information 802 to the TX UE. Configuration information 802 indicates the SL DRX configuration of the RX UE, and the TX UE may take into account the indicated SL DRX configuration when sending SL transmissions to the RX UE and when determining its own SL DRX configuration, for example, by adopting the same or similar parameters as the SL DRX configuration.

[0102] As further shown, the TX UE can then notify the access node AN2 of the SL DRX configuration determined for the RX UE by sending the corresponding configuration information 803 to its serving access node AN2.

[0103] As further shown, the TX UE can also send an acknowledgment 804 to the RX UE, indicating that the SL DRX configuration indicated by the configuration information 802 has been accepted by the TX UE.

[0104] As a result, the SL DRX configurations of the RX UE and TX UE are aligned. Based on the aligned SL DRX configuration, the TX UE can then send SL transmission 805 to the RX UE.

[0105] As can be seen, in Figure 8A In the example, the alignment of the SL DRX configuration can be based on exchanging configuration information via the SL transport that transmits configuration information 802. For example, the SL transport may include an RRC (Radio Resource Control) message indicating configuration information 802, such as an RRCReconfigurationSidelink message. Alternatively or additionally, at least a portion of the configuration information may be indicated by a MAC CE (Control Element) or PHY layer control signaling. Furthermore, access nodes AN1 and AN2 may be notified of the SL DRX configuration for the RX UE and TX UE. Figure 8A In the example, alignment of the SL DRX configuration can be performed, for example, when establishing or modifying the AS (Access Stratum) configuration for SL communication between the TX UE and the RX UE.

[0106] The indication of SL DRX configuration from RX UE to TX UE can be based on one or more of the following:

[0107] In some cases, the RX UE can be configured or pre-configured with multiple SL DRX configurations. For example, a corresponding SL DRX configuration can be configured or pre-configured for each destination identifier, unicast link, or resource pool. The RX UE can then select which SL DRX configuration to use for SL communication with the TX UE from these multiple DRX configurations. This selection can also be based on a mapping configured or pre-configured in the RX UE. For example, two SL DRX configurations can be provided, one for SL communication HARQ feedback and the other for SL communication without HARQ feedback. Depending on whether HARQ feedback is used for SL communication, for example, based on the service or QoS (Quality of Service) requirements of the SL communication, the RX UE can select one or the other of these two SL DRX configurations.

[0108] In some cases, the RX UE can use RRC signaling on the PC5 interface to indicate the SL DRX configuration to the TX UE, for example, via the RRCReconfigurationSidelink message. The TX UE can then forward the indicated SL DRX configuration to its serving access node. The TX UE or its serving access node can then decide whether to accept or reject the indicated SL DRX configuration. The TX UE can also notify the RX UE of this decision, for example, as described with respect to message 804. For the latter purpose, the TX UE can use RRC signaling on the PC5 interface.

[0109] - In some cases, multiple SL connections may exist between the RX UE and the TX UE, for example, multiple PC5 unicast links. In this case, the corresponding SL DRX configuration can be determined for each of the multiple SL connections, and the alignment process described above can be performed individually for each of the multiple SL connections.

[0110] In some cases, information exchange regarding the SL DRX configuration to be applied can be performed before any SL data radio bearer is established between the RX UE and the TX UE. If the indicated SL DRX configuration is not accepted by the corresponding other UE, the link failure can be declared and the corresponding SL connection released.

[0111] - In some cases, the exchange of information about the SL DRX configuration to be applied may involve only a subset of the parameters of the SL DRX configuration.

[0112] - In some cases, both the RX UE and the TX UE can be configured or pre-configured with multiple candidate SL DRX configurations, and an indication of the SL DRX configuration can be provided by identifying one of the candidate SL DRX configurations (e.g., in terms of indexing).

[0113] - In some cases, TX UE and RX UE may be provided with a configured or pre-configured common SL DRX configuration, and this common SL DRX configuration is applied when one or more SL transports are used to exchange information about the SL DRX configuration to be applied.

[0114] In one variant, the serving access node of the RX UE can provide the SL DRX configuration of the RX UE and indicate it to the serving access node of the TX UE. For this purpose, the serving access node of the RX UE can use signaling via the Xn interface to the serving access node of the TX UE or signaling via the AMF (Access and Mobility Management Function) of the wireless communication network. Furthermore, the serving access node of the TX UE can decide to accept or reject the indicated SL DRX configuration and notify the serving access node of the TX UE and / or the RX UE of this decision. The serving access node of the TX UE or the RX UE can then notify the RX UE of this decision. In some variants, the serving access node of the RX UE can indicate the SL DRX configuration to the RX UE only in response to the SL DRX configuration being accepted. If the SL DRX configuration is rejected, the serving access node of the RX UE can indicate an AS layer configuration failure to the RX UE.

[0115] Figure 8B An example of the process in which the serving access node of the RX UE provides the SL DRX configuration of the RX UE and instructs it to the serving access node of the TX UE is shown. Figure 8B The process involves the RX UE, the TX UE, the access node (AN1) serving the RX UE, and the access node (AN2) serving the TX UE.

[0116] exist Figure 8B During the process, access node AN1 generates the SL DRX configuration to be applied by the RX UE and sends configuration information (CI) 811 indicating the SL DRX configuration to the serving access node AN2 of the TX UE. The configuration information 811 can be transmitted via signaling to the serving access node AN2 of the TX UE through the Xn interface or via signaling through the AMF. Then, the serving access node AN2 of the TX UE can decide to accept or reject the indicated SL DRX configuration and notify the serving access node AN1 of the TX UE and / or the RX UE of this decision. Figure 8BIn the example, access node AN2 accepts the indicated SL DRX configuration and sends configuration information 812 indicating the SL DRX configuration to TX UE. Furthermore, access node AN2 sends an acknowledgment 813 to the serving access node AN1 of RX UE indicating acceptance of the SL DRX configuration. In response to receiving this acknowledgment, access node AN1 sends configuration information 814 to RX UE indicating the accepted SL DRX configuration. As a result, the SL DRX configurations of RX UE and TX UE are aligned. Based on the aligned SL DRX configuration, TX UE can then send SL transmissions to RX UE 815.

[0117] After receiving and accepting the RX UE's SL DRX configuration, the TX UE can consider the RX UE's SL DRX configuration when sending SL transmissions to the RX UE. In other words, the TX UE can send SCI and SL data only when the RX UE is awake and able to receive SL transmissions from the TX UE. Furthermore, after receiving and accepting the RX UE's SL DRX configuration (provided by the TX UE itself or the TX UE's serving access node), the TX UE uses the same SL DRX configuration for its own SL DRX procedure when receiving SL transmissions from the RX UE.

[0118] Therefore, in some scenarios, the RX UE can generate, receive, or select the SL DRX configuration to be used and send it to the TX UE so that the TX UE knows when the RX UE wakes up and can receive SL transmissions. For example, this variant can be applied when the RX UE is out of coverage or in the RRC_IDLE / INACTIVE state. In this case, the transmission of configuration information 801 can be omitted.

[0119] In some cases, the RX UE may be within coverage and in the RRC_CONNECTED state. In this scenario, the RX UE can send an AS configuration request for SL communication with the TX UE to the access node AN1, such as a SidelinkUEInformation message. Upon receiving the AS configuration request from the RX UE, the access node AN1 can provide configuration 801, thereby instructing the RX UE on SL DRX configuration. In this case, configuration information 801 can be transmitted, for example, via an RRC message, such as in an information element identified as SL-ConfigDedicatedNR.

[0120] Figure 9A An example of the process for aligning SL DRX configurations by exchanging configuration information between the RX UE and the TX UE is shown. Specifically, in Figure 9AIn the example, the TX UE determines the SL DRX configuration to be applied by the RX UE and indicates the determined SL DRX configuration to the RX UE. Figure 9A The process involves the RX UE, the TX UE, the access node (AN1) serving the RX UE, and the access node (AN2) serving the TX UE. Note that in some scenarios, the RX UE and the TX UE may also be served by the same access node.

[0121] exist Figure 9A During this process, Access Node AN2 can send Configuration Information (CI) 901 to the TX UE. Configuration Information 901 can, for example, indicate the TX UE's DL / UL DRX configuration and / or parameters that the TX UE will use to determine the SLDRX configuration to be applied by the RX UE. In some scenarios, Access Node AN2 can also determine the SL DRX configuration to be applied by the RX UE and use Configuration Information 901 to indicate the SL DRX configuration to the TX UE. In some scenarios, the TX UE can also use Configuration Information 901 to determine its own SL DRX configuration.

[0122] Then, the TX UE determines the SL DRX configuration to be applied by the RX UE and sends configuration information 902 to the RX UE. Configuration information 902 indicates the SL DRX configuration to be applied by the RX UE, and the RX UE may consider the indicated SL DRX configuration when determining its own SL DRX configuration, for example, by adopting the parameters of the indicated SL DRX configuration, by modifying the indicated SL DRX configuration, or by rejecting the indicated SL DRX configuration.

[0123] As further shown, the RX UE can also notify the access node AN1 of the SL DRX configuration determined for the RX UE by sending configuration information 903 to its serving access node AN1.

[0124] As further shown, the RX UE can also send an acknowledgment 904 to the RX UE, indicating that the SL DRX configuration indicated by the configuration information 902 has been accepted by the RX UE.

[0125] As a result, the SL DRX configurations of the RX UE and TX UE are aligned. Based on the aligned SL DRX configuration, the TX UE can then send SL transmission 905 to the RX UE.

[0126] As can be seen, in Figure 9AIn the example, the alignment of the SL DRX configuration can be based on exchanging configuration information via the SL transport that transmits configuration information 902. For example, the SL transport may include an RRC message indicating configuration information 902, such as an RRCReconfigurationSidelink message. Alternatively or additionally, at least a portion of the configuration information may be indicated by MACCE or PHY layer control signaling. Furthermore, access nodes AN1 and AN2 may be notified of the SLDRX configuration for the RX UE and TX UE. Figure 9A In the example, alignment of the SL DRX configuration can be performed, for example, when establishing or modifying the AS configuration for SL communication between the TX UE and the RX UE.

[0127] Therefore, in some scenarios, the TX UE can generate, receive, or select the SL DRX configuration to be used and send that SL DRX configuration to the RX UE. Thus, the TX UE knows about the RX UE's SL DRX configuration and knows when the RX UE wakes up and can receive SL transmissions. For example, this variant can be applied when the TX UE is out of coverage or in the RRC_IDLE / INACTIVE state. In this case, the transmission of configuration information 901 can be omitted.

[0128] In some cases, the TX UE may be within coverage and in the RRC_CONNECTED state. In this scenario, the TX UE can send an AS configuration request for SL communication with the RX UE to the access node AN2, for example, a SidelinkUEInformation message. After receiving the AS configuration request from the TX UE, the access node AN2 can provide configuration 901, thereby indicating the SL DRX configuration to the TX UE. In this case, configuration information 901 can be transmitted, for example, by an RRC message, such as in an information element marked SL-ConfigDedicatedNR. Therefore, the serving access node of the TX UE can generate the SL DRX configuration to be used by the RX UE after receiving the AS configuration request from the TX UE, and indicate the SL DRX configuration to the TX UE. Furthermore, the TX UE can further indicate the SL DRX configuration to the RX UE. The RX UE can immediately adopt the SL DRX configuration or use it as the basis for determining the updated SL DRX configuration to be applied by the RX UE.

[0129] Therefore, in some scenarios, the TX UE can provide the SL DRX configuration to be used by the RX UE and send it to the RX UE so that the RX UE knows when it should wake up and be able to receive SL transmissions. The TX UE can provide the SL DRX configuration, for example, when establishing or modifying the AS configuration for SL communication with the RX UE.

[0130] In some scenarios, when the TX UE and RX UE have agreed on the SL DRX configuration to be applied by the RX UE, the TX UE can consider the RX UE's SL DRX configuration when performing SL transmissions to the RX UE. For example, the TX UE can only transmit if the RX UE is woken up and able to receive SL transmissions from the TX UE.

[0131] The indication of SL DRX configuration from TX UE to RX UE can be based on one or more of the following:

[0132] In some cases, the TX UE can use RRC signaling on the PC5 interface to indicate the SL DRX configuration to the RX UE, for example, via the RRCReconfigurationSidelink message. The RX UE can then forward the indicated SL DRX configuration to its serving access node. The RX UE or its serving access node can then decide whether to accept or reject the indicated SL DRX configuration, or whether to update the indicated SL DRX configuration. The RX UE can also notify the TX UE of this decision, for example, as described with respect to message 904, and (if applicable) also indicate the updated SL DRX configuration. For the latter purpose, the TX UE can use RRC signaling on the PC5 interface.

[0133] When the RX UE has indicated an updated SL DRX configuration, the TX UE or its serving access node can determine whether to accept the updated SL DRX configuration and notify the RX UE of this decision. If the TX UE and RX UE have agreed on the SL DRX configuration, the TX UE should only send SCI and SL data to the RX UE when the RX UE is expected to wake up according to the agreed SL DRX configuration. If the TX UE and RX UE have not agreed on the SL DRX configuration, an AS configuration failure procedure can be triggered and the corresponding bearer can be released.

[0134] - In some cases, the RX UE may notify its serving access node about the SL DRX configuration indicated by the TX UE (e.g., as described with respect to configuration information 903), and the serving access node of the RX UE may notify the RX UE whether the indicated SL DRX configuration is accepted or rejected, and whether an updated SL DRX configuration needs to be determined from the indicated SL DRX configuration.

[0135] - In some cases, the TX UE can indicate the updated SL DRX configuration provided by the RX UE to the TX UE's serving access node, and the TX UE's serving access node can notify the TX UE whether the updated SL DRX configuration is accepted or rejected.

[0136] - In some cases, multiple SL connections may exist between the RX UE and the TX UE, for example, multiple PC5 unicast links. In this case, the corresponding SL DRX configuration can be determined for each of the multiple SL connections, and the alignment process described above can be performed individually for each of the multiple SL connections.

[0137] In some cases, information exchange regarding the SL DRX configuration to be applied can be performed before any SL data radio bearer is established between the RX UE and the TX UE. If the indicated SL DRX configuration is not accepted by the corresponding other UE, the link failure can be declared and the corresponding SL connection released.

[0138] - In some cases, the exchange of information about the SL DRX configuration to be applied may involve only a subset of the parameters of the SL DRX configuration.

[0139] - In some cases, both the RX UE and the TX UE can be configured or pre-configured with multiple candidate SL DRX configurations, and an indication of the SL DRX configuration can be provided by identifying one of the candidate SL DRX configurations (e.g., in terms of indexing).

[0140] - In some cases, TX UE and RX UE may be provided with a configured or pre-configured common SL DRX configuration, and this common SL DRX configuration is applied when one or more SL transports are used to exchange information about the SL DRX configuration to be applied.

[0141] In one variant, the serving access node of the TX UE can provide and indicate the SL DRX configuration for the RX UE to the serving access node of the RX UE. For this purpose, the serving access node of the RX UE can use signaling via the Xn interface to the serving access node of the TX UE or signaling via the AMF of the wireless communication network. Furthermore, the serving access node of the RX UE can decide whether to accept or reject the indicated SL DRX configuration, or whether the indicated SL DRX configuration should be updated, and notify the serving access nodes of the RX UE and / or TX UE of this decision, or (if applicable) the updated SL DRX configuration. Subsequently, the serving access node of the RX UE or TX UE can notify the TX UE of this decision.

[0142] Figure 9B An example of the process in which the serving access node of the TX UE provides the SL DRX configuration of the RX UE and instructs it to the serving access node of the RX UE is shown. Figure 9B The process involves the RX UE, the TX UE, the access node (AN1) serving the RX UE, and the access node (AN2) serving the TX UE.

[0143] exist Figure 9B During this process, access node AN2 generates the SL DRX configuration to be applied by the RX UE and sends configuration information (CI) 911 indicating this SL DRX configuration to the serving access node AN1 of the RX UE. The configuration information 911 can be transmitted via signaling to the serving access node AN1 of the RX UE through the Xn interface or via signaling through the AMF. Then, the serving access node AN1 of the TX UE can decide whether to accept or reject the indicated SL DRX configuration, or whether the indicated SL DRX configuration should be updated, and notify the serving access node AN2 of the RX UE and / or TX UE of this decision. Figure 9B In the example, access node AN1 accepts the indicated SL DRX configuration and sends configuration information 912 indicating the SL DRX configuration to the RX UE. Furthermore, access node AN1 sends an acknowledgment 913 indicating acceptance of the SL DRX configuration to the serving access node AN2 of the TX UE. In response to receiving the acknowledgment 913, access node AN2 sends configuration information 914 indicating the accepted SL DRX configuration to the TX UE. As a result, the SL DRX configurations of the RX UE and the TX UE are aligned. Based on the aligned SL DRX configuration, the TX UE can then send SL transmissions to the RX UE 915.

[0144] As mentioned above, alignment of SL DRX configuration and DL / UL DRX configuration can also be expected. Here, two specific types of alignment are involved: alignment of the DL / UL DRX configuration of the RX UE with the SL DRX configuration of the RX UE, and alignment of the DL / UL DRX configuration of the TX UE with the SL DRX configuration of the RX UE.

[0145] DL / UL DRX configuration may include one or more of the following parameters and timers:

[0146] The timer labeled "drx-onDurationTimer" is defined as the duration at the start of the DL / UL DRX cycle;

[0147] The parameter labeled "drx-SlotOffset" is defined as the delay before the timer drx-onDurationTimer is started;

[0148] The parameter labeled "drx-LongCycleStartOffset" defines the long DL / UL DRX cycle;

[0149] The parameter labeled "drx-StartOffset" is defined in the subframe at the start of its (long or short) DL / UL DRX cycle;

[0150] The optional parameter labeled "drx-ShortCycle" defines the short DL / UL DRX cycle;

[0151] An optional timer labeled “drx-ShortCycleTimer” indicates the duration for which the UE should follow the short DL / UL DRX cycle;

[0152] The timer labeled “drx-InactivityTimer” is defined as the duration after receiving a PDCCH (Physical Downlink Control Channel) event that includes DCI information indicating a new DL or UL (Uplink) transmission.

[0153] The timer labeled "drx-RetransmissionTimerDL" is defined as the maximum duration until a DL retransmission is received, and is typically defined per DL HARQ process, except for broadcast SL transmissions;

[0154] The timer labeled “drx-RetransmissionTimerUL” is defined as the maximum duration until a UL retransmission is received, and is typically defined per UL HARQ process, except for broadcast SL transmissions;

[0155] The timer labeled “drx-HARQ-RTT-TimerDL” is defined as the minimum duration before the DL retransmission authorization for DL ​​HARQ retransmission is expected on the PDCCH by the MAC entity, and is typically defined per DL HARQ process.

[0156] The timer labeled “drx-HARQ-RTT-TimerUL” is defined as the minimum duration prior to the DL retransmission authorization for UL HARQ retransmission on the PDCCH that the MAC entity expects, typically defined per UL HARQ process.

[0157] When DL / UL DRX is configured, the UE should wake up, i.e., be in DRX active time, when any of the timers drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, or drx-RetransmissionTimerUL is running. If the received PDCCH indicates a new transmission (DL or UL), the timer drx-InactivityTimer is started or restarted. When the timer drx-InactivityTimer expires, the UE uses a short DRX cycle, and if a short DRX cycle is configured, the drx-ShortCycleTimer is started or restarted; otherwise, it uses a long DRX cycle. If the PDCCH indicates a UL transmission or MAC PDU is sent in the configured UL grant, the timer drx-HARQ-RTT-TimerUL is started and the timer drx-RetransmissionTimerUL is stopped for the corresponding HARQ procedure after the first repetition of the corresponding PUSCH transmission ends. If timer drx-HARQ-RTT-TimerUL expires, then drx-RetransmissionTimerUL is started for the corresponding HARQ procedure. If the PDCCH indicates in the configured DL grant that a DL transmission or MAC PDU has been received, then after the corresponding transmission carrying DL HARQ feedback has ended, timer drx-HARQ-RTT-TimerDL is started and drx-RetransmissionTimerDL is stopped for the corresponding HARQ procedure. If timer drx-HARQ-RTT-TimerDL expires and the data for the corresponding HARQ procedure has not been successfully decoded, then timer drx-RetransmissionTimerDL is started for the corresponding HARQ procedure.

[0158] Alignment of the RX UE's DL / UL DRX configuration with the RX's SL DRX configuration can be performed by the RX UE itself or by the access node serving the RX UE. For example, if the alignment is performed by the RX UE's serving access node, the access node can indicate the SL DRX configuration and DL / UL DRX configuration to the RX UE using the relationship between the SL DRX configuration and the DL / UL DRX configuration. In particular, instead of indicating a first set of parameters for the SL DRX configuration and a separate second set of parameters for the DL / UL DRX configuration, the access node can indicate a set of parameters for one of the SL DRX configurations or the DL / UL DRX configuration, and indicate the other of the SL DRX configuration and DL / UL DRX configuration in terms of deviation from the indicated set of parameters (e.g., in terms of one or more incremental values, where each incremental value represents a difference between a parameter of the SL DRX configuration and a corresponding parameter of the DL / UL DRX configuration). By way of example, for timer drx-InactivityTimerSL, the service access node can indicate the setting of timer drx-InactivityTimer for DL / UL DRX configuration, and the incremental value indicating the difference between the settings of timer drx-InactivityTimer and drx-InactivityTimerSL. Alternatively, the service access node can indicate the setting of timer drx-InactivityTimerSL for SL DRX configuration, and the incremental value indicating the difference between the settings of timer drx-InactivityTimer and drx-InactivityTimerSL. A similar approach can be used for all parameters applied in both SLDRX and DL / UL DRX configurations, but with different settings.

[0159] Figure 10 An example of the process in which the access node serving the RX UE aligns the SL DRX configuration and DL / UL DRX configuration of the RX UE is shown. Figure 10 The process involves the RX UE, the TX UE, and the access node (AN) serving the RX UE.

[0160] exist Figure 10In the example, the access node AN serving the RX UE sends configuration information (CI) 1001 to the RX UE. Configuration information 1001 indicates at least a portion of the SL DRX configuration to be applied by the RX UE and at least a portion of the DL / UL DRX configuration to be applied by the RX UE. This configuration information indicates the set of parameters used for the DL / UL DRX configuration, and the deviation from the indicated parameter set for the SL DRX configuration, for example, in terms of one or more incremental values, where each incremental value represents a difference between the parameters of the SL DRX configuration and the corresponding parameters of the DL / UL DRX configuration. Alternatively, configuration information 1001 may indicate the set of parameters used for the SL DRX configuration, and the deviation from the indicated parameter set for the DL / UL DRX configuration, for example, in terms of one or more incremental values, where each incremental value represents a difference between the parameters of the SL DRX configuration and the corresponding parameters of the DL / UL DRX configuration. Based on configuration information 1001, the RX UE determines and aligns its SL DRX configuration and DL / UL DRX configuration. Based on the aligned DRX configuration, the RX UE can then receive SL transmission 1002 from the TX UE.

[0161] In some scenarios, for example, such as in Figure 9A and Figure 9B In the example, the alignment of the SL DRX configuration and the DL / UL DRX configuration may involve the TX UE or the access node serving the TX UE providing the SL DRX configuration to be applied by the RX UE and indicating that SL DRX configuration to the RX. In this case, when the SL DRX configuration is provided, the TX UE or the access node serving the TX UE may consider the DL / UL DRX configuration of the RX UE. Information about the DL / UL DRX configuration of the RX UE can be obtained from the RX UE or from the access node serving the RX UE. For example, the RX UE may use SL transmission to indicate its DL / UL DRX configuration to the TX UE (e.g., RRC signaling on the PC5 interface), and optionally, the TX UE may forward this information to its serving access node. Furthermore, the serving access node of the RX UE may (e.g., via the Xn interface or via AMF) indicate the DL / UL DRX configuration of the RX UE to the serving access node of the TX UE, and optionally, the serving access node of the TX UE may forward this information to the TX UE.

[0162] Figure 11 An example of the process in which the SL DRX configuration and DL / UL DRX configuration of the RX UE are aligned by the TX UE is shown. Figure 11 The process involves the RX UE, the TX UE, the access node (AN1) serving the RX UE, and the access node (AN2) serving the TX UE.

[0163] exist Figure 11 In the example, the RX UE sends configuration information (CI) 1101 to the TX UE. Configuration information 1101 indicates the DL / UL DRX configuration of the RX UE.

[0164] Based on the indicated DL / ULDRC configuration, the TX UE then determines the SL DRX configuration to be applied by the RX UE and sends configuration information 1102 to the RX UE. Configuration information 1102 indicates the SL DRX configuration to be applied by the RX UE, and the RX UE may consider the indicated SL DRX configuration when determining its own SL DRX configuration, for example, by adopting the parameters of the indicated SL DRX configuration, by modifying the indicated SL DRX configuration, or by rejecting the indicated SL DRX configuration.

[0165] As further shown, the RX UE can also notify the access node AN1 of the SL DRX configuration determined for the RX UE by sending the corresponding configuration information 1103 to its serving access node AN1.

[0166] As further shown, the RX UE can also send an acknowledgment 1104 to the TX UE, indicating that the SL DRX configuration indicated by the configuration information 1102 has been accepted by the RX UE.

[0167] As further shown, the TX UE can also notify the access node AN2 of the SL DRX configuration determined for the RX UE by sending the corresponding configuration information 1105 to its serving access node AN2.

[0168] As a result, the SL DRX configuration and DL / UL of the RX UE are aligned. Based on the aligned DRX configuration, the RX UE can then receive SL transmission 1105 from the TX UE.

[0169] In one variant, where the access node of the TX UE or serving TX UE provides the SLDRX configuration to be applied by the RX UE, for example, as in Figure 9A , Figure 9B and Figure 11 In the example, the TX UE can notify the RX UE of its SL DRX configuration, for example, by sending an SL transmission, such as an SL transmission carrying configuration information 902 or 1102. The RX UE can then forward this information to its serving access node, for example, by sending corresponding configuration information, such as configuration information 903 or 1103. Furthermore, the serving access node of the RX UE can adjust or reconfigure the RX UE's DL / UL DRX configuration.

[0170] To align the DL / UL DRX configuration of the TX UE with the SL DRX configuration of the RX UE, the TX UE or the access node serving the TX UE can provide the SL DRX configuration to be applied by the RX UE, for example, as in Figure 9A , Figure 9B and Figure 11 In the example, when determining the SL DRX configuration to be applied by the RX UE, the TX UE or the access node serving the TX UE may also consider the DL / UL DRX configuration of the TX UE. If the alignment is performed by the serving access node of the TX UE, the serving access node of the TX UE may also indicate to the TX UE a set of parameters for one of the SL DRX configurations or the DL / UL DRX configuration using the options mentioned above, and indicate the other of the SL DRX configuration and the DL / UL DRX configuration in terms of deviation from the indicated set of parameters (e.g., in terms of one or more incremental values, where each incremental value represents the difference between the parameters of the SL DRX configuration and the corresponding parameters of the DL / UL DRX configuration).

[0171] In some scenarios, the RX UE or the access node serving the RX UE provides the SL DRX configuration that will be applied by the RX UE, for example, as in Figure 8A , Figure 8B and Figure 10 In the example, alignment of the DL / UL DRX configuration of the TX UE and the SL DRX configuration of the RX UE can also be achieved. In this case, when the SL DRX configuration is provided, the RX UE or the access node serving the RX UE can consider the DL / UL DRX configuration of the TX UE. Information about the DL / UL DRX configuration of the TX UE can be obtained from the TX UE or from the access node serving the TX UE. For example, the TX UE can use SL transmission to indicate its DL / UL DRX configuration to the RX UE (e.g., RRC signaling on the PC5 interface), and optionally, the RX UE can forward this information to its serving access node. Furthermore, the serving access node of the TX UE can (e.g., via the Xn interface or via AMF) indicate the DL / UL DRX configuration of the TX UE to the serving access node of the RX UE, and optionally, the serving access node of the RX UE can forward this information to the RX UE.

[0172] In one variant, where the RX UE or the access node serving the RX UE provides the SL DRX configuration to be applied by the RX UE, for example, as in Figure 8A , Figure 8B and Figure 10In the example, the RX UE can notify the TX UE of its SL DRX configuration, for example, by sending an SL transmission, such as an SL transmission carrying configuration information 802. The TX UE can then forward this information to its serving access node, for example, by sending corresponding configuration information, such as configuration information 803. The serving access node of the TX UE can then adjust or reconfigure the DL / UL DRX configuration of the TX UE.

[0173] Figure 12 A flowchart illustrating the methods that can be used to implement the concepts described is shown. Figure 12 The method can be used to implement the described concepts in wireless communication devices (corresponding to any of the UEs mentioned above). In some scenarios, the wireless communication device can be a vehicle or an in-vehicle device, but other types of WDs, such as those mentioned above, can also be used.

[0174] If a processor-based implementation of a wireless communication device is used, then Figure 12 At least some steps of the method can be executed and / or controlled by one or more processors of the wireless communication device. Such a wireless communication device may also include storage for implementing at least some of the steps described below. Figure 12 The memory of the program code containing the function or steps of the method.

[0175] At step 1210, the wireless communication device determines a DRX configuration for D2D communication with another wireless communication device. This DRX configuration is based on at least one timer maintained by the wireless communication device. The D2D communication may, for example, correspond to SL communication via a PC5 interface using LTE or NR technology. The DRX configuration may, for example, correspond to the SL DRX configuration mentioned above that will be applied by the RX UE.

[0176] The wireless communication device can determine at least a portion of the DRX configuration based on the DRX configuration used for downlink or uplink communication with the wireless communication network. Furthermore, the wireless communication device can determine at least a portion of the DRX configuration based on the characteristics of D2D communication between the wireless communication device and another wireless communication device (e.g., based on whether HARQ feedback or other acknowledgment feedback is required).

[0177] At step 1220, the wireless communication device may align with another wireless communication device that configures the DRX. Alignment at step 1220 allows the other wireless communication device to avoid sending D2D transmissions to the aligned wireless communication device, while, depending on the aligned DRX configuration, the wireless communication device is not in an active mode for receiving D2D transmissions, for example, not during DRX active time. Alignment at step 1230 may be performed, for example, with respect to the duration of at least one timer and / or parameters used to derive the duration of at least one timer.

[0178] The alignment in step 1220 may involve the wireless communication device determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to another wireless communication device. For example, this can be done by sending the configuration information (e.g., as...) Figure 8A The configuration information (802) in the example is used to implement this. In some scenarios, the wireless communication device can indicate the determined configuration information by transmitting it via D2D to another wireless communication device. Furthermore, the configuration information can be indicated by the following items transmitted via D2D to another wireless communication device: RRC information, MAC control information, and / or PHY layer control information. In some scenarios, the wireless communication device can also send the configuration information indirectly, for example, via an access node serving the wireless communication device and / or an access node serving another wireless communication device.

[0179] Alternatively, the alignment in step 1220 may involve the wireless communication device determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to a node in the wireless communication network associated with the other wireless communication device (e.g., an access node serving the other wireless communication device). This can also be achieved indirectly via the other wireless communication device or the access node serving the wireless communication device. For example, the wireless communication device may send configuration information (e.g., configuration information 802) to the other wireless communication device, and the other wireless communication device may then propagate the configuration information to its serving access node, for example, using configuration information 803.

[0180] Alternatively, the alignment in step 1220 may involve the wireless communication device determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to a node of the wireless communication network to which the wireless communication device is associated (e.g., an access node serving the wireless communication device), for example, using configuration information 903 or 1103.

[0181] In some scenarios, the wireless communication device can determine at least a portion of the configuration information based on configuration information received from a node of the wireless communication network (e.g., from an access node serving the wireless communication device) (such as configuration information 801, 814, 912, or 1001).

[0182] In some scenarios, the wireless communication device can determine at least a portion of the configuration information based on the DRX configuration used for communication with the wireless communication network via DL or UL.

[0183] In some scenarios, the wireless communication device can determine at least a portion of the configuration information based on the characteristics of D2D communication between the wireless communication device and another wireless communication device (e.g., based on whether HARQ feedback or other confirmation feedback is required).

[0184] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving confirmation information (e.g., confirmation 804) in response to an indication of the determined configuration information.

[0185] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving an acknowledgment from the node (indicating whether the determined configuration information is accepted) in response to indicating the determined configuration information to the node, and the wireless communication device forwarding the acknowledgment to another wireless communication device.

[0186] In some scenarios, the alignment in step 1220 may involve the wireless communication device declaring a failure of the D2D link between itself and another wireless communication device in response to the confirmation message indicating that the determined configuration information has not been accepted. In some cases, the alignment in step 1220 may additionally or alternatively involve the wireless communication device initiating the release or reconfiguration of bearers configured on the D2D link between itself and another wireless communication device in response to the confirmation message indicating that the determined configuration information has not been accepted. For example, the latter variation may be useful if multiple bearers are configured on the D2D link and the unaccepted configuration information pertains only to a subset of the bearers.

[0187] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving configuration information from another wireless communication device and determining at least a portion of the DRX configuration based on the configuration information received from the other wireless communication device (e.g., configuration information 902, 1102).

[0188] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving configuration information from another wireless communication device and determining the DRX configuration for downlink or uplink communication with the wireless communication network based on the received configuration information (e.g., configuration information 1102). This configuration information may be received based on a D2D transmission received from the other wireless communication device. Furthermore, the received configuration information may be indicated by the following items transmitted by the D2D transmission from the other wireless communication device: RRC control information, MAC control information, and / or physical layer control information. In some scenarios, the wireless communication device may also receive the configuration information indirectly, for example, via an access node serving the wireless communication device and / or an access node serving another wireless communication device.

[0189] In some scenarios, the wireless communication device may forward at least a portion of configuration information received from another wireless communication device to a node in the wireless communication network, such as the serving access node of the wireless communication device. The forwarded configuration may correspond to at least a portion of the determined DRX configuration for D2D communication. Furthermore, the wireless communication device may receive acknowledgment information from the node. This acknowledgment information may indicate whether the forwarded configuration information has been accepted. Subsequently, the wireless communication device may forward the acknowledgment information to another wireless communication device.

[0190] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving configuration information from a node of the wireless communication network (e.g., from an access node serving the wireless communication device or an access node serving another wireless communication device) and determining at least a portion of the DRX configuration based on the configuration information received from the node of the wireless communication network (e.g., configuration information 801, 912, or 1001).

[0191] In some scenarios, the alignment in step 1220 may involve the wireless communication device receiving configuration information from a node of the wireless communication network (e.g., from an access node serving the wireless communication device or an access node serving another wireless communication device) and determining the DRX configuration for communicating with the DL or UL of the wireless communication network based on the received configuration information (e.g., configuration information 801, 1001).

[0192] In some scenarios, the alignment in step 1220 may involve the wireless communication device sending an acknowledgment message indicating whether the received configuration information is accepted in response to receiving configuration information.

[0193] In each of the above examples using configuration information, the configuration information may indicate at least a portion of the DRX configuration for D2D communication in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration for DL ​​or UL communication with the wireless communication network. Furthermore, the configuration information may indicate at least a portion of the DRX configuration by identifying one of a plurality of pre-configured (e.g., pre-configured based on standards, operator settings, or network configuration) DRX configurations.

[0194] At step 1230, the wireless communication device controls at least one timer based on at least one D2D transmission between the wireless communication device and another wireless communication device.

[0195] At least one timer may include at least one first timer for controlling the wireless communication device to be in an active mode of receiving with D2D transmission enabled (e.g., during DRX active time) when the first timer has not expired. Examples of the at least one first timer include the timers mentioned above: drx-onDurationTimerSL, drx-InactivityTimerSL, drx-RetransmissionTimerSL, drx-HARQ-FB-TimerSL, drx-CSIReport-TimerSL, and drx-BlindRetransmissionTimerSL.

[0196] In some scenarios, at least one first timer may include a retransmission timer that is activated in response to an incoming D2D transmission received by the wireless communication device failing to be successfully decoded.

[0197] In some cases, incoming D2D transmissions require acknowledgment feedback (e.g., HARQ feedback). An example of a retransmission timer in this case is the aforementioned timer drx-RetransmissionTimerSL. In this scenario, step 1230 may involve the wireless communication device initiating a retransmission timer in response to the expiration of a second timer (which responds to the receipt of an incoming D2D transmission), wherein the second timer is associated with the round-trip time of the acknowledgment feedback. An example of the second timer in this case is the aforementioned timer drx-HARQ-RTT-TimerSL. The round-trip time of the acknowledgment feedback can be defined as the time interval between sending the acknowledgment feedback and the earliest possible time for receiving a retransmission of the incoming D2D transmission or for resource authorization for a retransmission of the incoming D2D transmission. In some scenarios, step 1230 may also involve the wireless communication device selectively deciding whether to initiate the retransmission timer and / or the second timer based on the scheduling mode associated with the incoming D2D transmission. For example, in the case of LTE or NR SL transmissions, different modes can be used to allocate or select resources for SL transmissions; these modes are denoted as "Mode 1", "Mode 2", "Mode 3", and "Mode 4". In modes 1 and 3, the selection of resources for SL transmission is network-assisted, while in modes 2 and 4, the transmitting wireless communication device selects resources autonomously. For some scheduling modes, such as those using network assistance, acknowledgment feedback may be less important and is sometimes ignored. This can be considered when selectively deciding whether to start a retransmission timer and / or a second timer.

[0198] In some cases, incoming D2D transmissions may be required without acknowledgment feedback. In this scenario, an example of a retransmission timer is the aforementioned timer drx-BlindRetransmissionTimerSL. In this case, step 1230 may involve the wireless communication device starting a retransmission timer in response to the expiration of a second timer (which is started in response to the receipt of an incoming D2D transmission), wherein the second timer is associated with the timing of the anticipated blind retransmission of the incoming D2D transmission. In this scenario, an example of a second timer is the aforementioned timer drx-Retx-Proc-TimerSL. The duration of the second timer may depend on the time gap between subsequent reservations made by another wireless communication device for a set of radio resources used for D2D communication. The wireless communication device or a node of the wireless communication network (e.g., a serving access node of the wireless communication device) can determine the duration of the second timer based on the time gap between subsequent reservations made by another wireless communication device for a set of radio resources used for D2D communication. The duration of the retransmission timer can be based on at least one of the following: control information associated with the incoming D2D transmission, the maximum duration of retransmissions associated with the incoming D2D transmission, and the maximum number of retransmissions associated with the incoming D2D transmission. A node of a wireless communication device or wireless communication network (e.g., a serving access node of the wireless communication device) can determine the duration of the retransmission timer based on at least one of the following: control information associated with the incoming D2D transmission, the maximum duration of retransmissions associated with the incoming D2D transmission, and the maximum number of retransmissions associated with the incoming D2D transmission. Note that the duration is the running time of the timer from its first start or reset to its expiration, without considering possible time intervals during which the timer may be paused. In some scenarios, after receiving an incoming D2D transmission, the wireless communication device can start the retransmission timer in the Nth symbol after the end of the incoming D2D transmission in response to the expiration of a configured time interval, where N is 1 or greater.

[0199] Furthermore, step 1230 may involve the wireless communication device stopping the retransmission timer in response to successfully decoding a retransmission associated with an incoming D2D transmission.

[0200] In some scenarios, at least one first timer may include a feedback timer that is activated in response to an outgoing D2D transmission sent by the wireless communication device (requiring acknowledgment feedback from another wireless communication device). An example of a feedback timer is the aforementioned timer drx-HARQ-FB-TimerSL. In this case, step 1230 may involve the wireless communication device activating the feedback timer in response to the expiration of a second timer (activated in response to sending an outgoing D2D transmission), wherein the second timer is associated with the round-trip time of the acknowledgment feedback. An example of the second timer in this case is the aforementioned timer drx-HARQ-FB-RTT-TimerSL. The duration of the second timer is based on the processing power of the other wireless communication device or on the periodicity of radio resources used for sending acknowledgment feedback. The wireless communication device or a node of the wireless communication network (e.g., the serving access node of the wireless communication device) may determine the duration of the second timer based on the processing power of the other wireless communication device or on the periodicity of radio resources used for sending acknowledgment feedback. The round-trip time for acknowledgment feedback can be defined as the time interval between sending an outgoing D2D transmission (specifically, the end time of the outgoing D2D transmission) and the earliest possible time to receive acknowledgment feedback. Similarly, duration is the runtime of a timer from its first start or reset to its expiration, without considering possible time intervals during which the timer may be paused.

[0201] Furthermore, step 1230 may involve the wireless communication device stopping the feedback timer in response to successfully receiving acknowledgment feedback for transmitting D2D data.

[0202] In some scenarios, at least one first timer may include a report timer that is activated in response to the wireless communication device sending an outgoing D2D transmission that triggers a measurement report from another wireless communication device. An example of a report timer is the aforementioned timer drx-CSIReport-TimerSL. In this case, step 1230 may involve the wireless communication device activating the report timer in response to the expiration of a second timer (activated in response to the transmission of an outgoing D2D transmission), wherein the second timer is associated with the round-trip time of the measurement report. An example of the second timer in this case is the aforementioned timer drx-CSIReport-RTT-TimerSL. The round-trip time of the measurement report can be defined as the time interval between sending an outgoing D2D transmission (specifically, the end time of the outgoing D2D transmission) and the earliest possible time of receiving the measurement report.

[0203] Furthermore, step 1230 may involve the wireless communication device stopping the reporting timer in response to successfully receiving a measurement report.

[0204] At step 1240, the wireless communication device receives at least one D2D transmission from another wireless communication device. For example, the wireless communication device may receive at least one D2D transmission during DRX active time and may control the switching to or from DRX active time based on at least one timer.

[0205] Figure 13 The illustration is shown according to Figure 12 The block diagram illustrates the functionality of the wireless communication device 1300 operated by the method described above. The wireless communication device 1300 may correspond to any of the UEs mentioned above. As shown, the wireless communication device 1300 may be provided with a module 1310 configured to determine a DRX configuration for D2D communication with another wireless communication device (as described in conjunction with step 1210). Furthermore, the wireless communication device 1300 may be provided with a module 1320 configured to align the DRX configuration with the other wireless communication device (as described in conjunction with step 1220). Additionally, the wireless communication device 1300 may be provided with a module 1330 configured to control at least one timer for the DRX configuration based on D2D transmissions (as described in conjunction with step 1230). Furthermore, the wireless communication device 1300 may be provided with a module 1340 configured to receive at least one D2D transmission (as described in conjunction with step 1240).

[0206] Note that the wireless communication device 1300 may include other modules for implementing other functions (such as known functions of the UE in LTE and / or NR radio technologies). Furthermore, note that the modules of the wireless communication device 1300 do not necessarily represent the hardware structure of the wireless communication device 1300, but may also correspond to functional elements (e.g., implemented by hardware, software, or a combination thereof).

[0207] Figure 14 A flowchart illustrating the methods that can be used to implement the concepts described is shown. Figure 14 The method can be used to implement the illustrated concepts in wireless communication devices (e.g., corresponding to any of the UEs mentioned above). In some scenarios, the wireless communication device may be a vehicle or an in-vehicle device, but other types of WDs, such as those mentioned above, may also be used.

[0208] If a processor-based implementation of a wireless communication device is used, then Figure 14 At least some steps of the method can be executed and / or controlled by one or more processors of the wireless communication device. Such a wireless communication device may also include storage for implementing at least some of the steps described below. Figure 14The memory of the program code containing the function or steps of the method.

[0209] At step 1410, the wireless communication device determines a DRX configuration for D2D communication with another wireless communication device. This DRX configuration is based on at least one timer maintained by the wireless communication device. The D2D communication may, for example, correspond to SL communication via a PC5 interface using LTE or NR technology. The DRX configuration may, for example, correspond to the SL DRX configuration mentioned above that will be applied by the RX UE. The D2D communication may involve the wireless communication device receiving at least one D2D communication from another wireless communication device. Alternatively or additionally, the D2D communication may involve the wireless communication device sending at least one D2D transmission to another wireless communication device.

[0210] The wireless communication device can determine at least a portion of the DRX configuration based on the DRX configuration used for DL ​​or UL communication with the wireless communication network. Furthermore, the wireless communication device can determine at least a portion of the DRX configuration based on the characteristics of D2D communication between the wireless communication device and another wireless communication device (e.g., based on whether HARQ feedback or other acknowledgment feedback is required).

[0211] At step 1420, the wireless communication device aligns its DRX configuration with that of another wireless communication device. To receive D2D transmissions from the other wireless communication device, the alignment in step 1420 allows the other wireless communication device to avoid sending D2D transmissions to the first wireless communication device, while, according to the aligned DRX configuration, the first wireless communication device is not in an active mode for receiving D2D transmissions enabled, for example, not during a DRX active period. To send D2D transmissions to the other wireless communication device, the alignment in step 1430 allows the first wireless communication device to avoid sending D2D transmissions to the first wireless communication device, while, according to the aligned DRX configuration, the other wireless communication device is not in an active mode for receiving D2D transmissions enabled, for example, not during a DRX active period. The alignment in step 1420 can, for example, be performed for the duration of at least one timer and / or parameters used to derive the duration of at least one timer.

[0212] The alignment in step 1420 may involve the wireless communication device determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to another wireless communication device. For example, this can be done by sending the configuration information (e.g., as...) Figure 8AThe configuration information (802) in the example is used to implement this. In some scenarios, the wireless communication device can indicate the determined configuration information by transmitting it via D2D to another wireless communication device. Furthermore, the configuration information can be indicated by the following items transmitted via D2D to another wireless communication device: RRC information, MAC control information, and / or PHY layer control information. In some scenarios, the wireless communication device can also send the configuration information indirectly, for example, via an access node serving the wireless communication device and / or an access node serving another wireless communication device.

[0213] Alternatively, the alignment in step 1420 may involve the wireless communication device determining configuration information for at least a portion of the DRX configuration and indicating the determined configuration information to a node in the wireless communication network associated with the other wireless communication device (e.g., an access node serving the other wireless communication device). This can also be achieved indirectly via the other wireless communication device or the access node serving the wireless communication device. For example, the wireless communication device may send configuration information (e.g., configuration information 802) to another wireless communication device, and the other wireless communication device may then propagate the configuration information to its serving access node, for example, using configuration information 803.

[0214] Alternatively, the alignment in step 1420 may involve the wireless communication device determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to a node of the wireless communication network to which the wireless communication device is associated (e.g., an access node serving the wireless communication device), for example, using configuration information 903 or 1103.

[0215] In some scenarios, the wireless communication device can determine at least a portion of the configuration information based on configuration information received from a node of the wireless communication network (e.g., from an access node serving the wireless communication device) (such as configuration information 801, 814, 912, or 1001).

[0216] In some scenarios, the wireless communication device can determine at least a portion of the configuration information based on the DRX configuration used for communication with the wireless communication network via DL or UL.

[0217] In some scenarios, the wireless communication device may determine at least a portion of the configuration information based on the characteristics of D2D communication between the wireless communication device and another wireless communication device (e.g., whether HARQ feedback or other confirmation feedback is required).

[0218] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving confirmation information (e.g., confirmation 804) in response to an indication of the determined configuration information.

[0219] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving an acknowledgment from the node (indicating whether the determined configuration information is accepted) in response to indicating the determined configuration information to the node, and the wireless communication device forwarding the acknowledgment to another wireless communication device.

[0220] In some scenarios, the alignment in step 1420 may involve the wireless communication device declaring a failure of the D2D link between itself and another wireless communication device in response to the confirmation message indicating that the determined configuration information has not been accepted. In some cases, the alignment in step 1420 may additionally or alternatively involve the wireless communication device initiating the release or reconfiguration of bearers configured on the D2D link between itself and another wireless communication device in response to the confirmation message indicating that the determined configuration information has not been accepted. For example, the latter variation may be useful if multiple bearers are configured on the D2D link and the unaccepted configuration information pertains only to a subset of the bearers.

[0221] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving configuration information from another wireless communication device and determining at least a portion of the DRX configuration based on the configuration information received from the other wireless communication device (e.g., configuration information 902, 1102).

[0222] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving configuration information from another wireless communication device and determining the DRX configuration for downlink or uplink communication with the wireless communication network based on the received configuration information (e.g., configuration information 1102). This configuration information may be received based on a D2D transmission received from the other wireless communication device. Furthermore, the received configuration information may be indicated by the following items transmitted by the D2D transmission from the other wireless communication device: RRC control information, MAC control information, and / or physical layer control information. In some scenarios, the wireless communication device may also receive the configuration information indirectly, for example, via an access node serving the wireless communication device and / or an access node serving another wireless communication device.

[0223] In some scenarios, the wireless communication device may forward at least a portion of configuration information received from another wireless communication device to a node in the wireless communication network, such as the serving access node of the wireless communication device. The forwarded configuration may correspond to at least a portion of the determined DRX configuration for D2D communication. Furthermore, the wireless communication device may receive acknowledgment information from the node. This acknowledgment information may indicate whether the forwarded configuration information has been accepted. Subsequently, the wireless communication device may forward the acknowledgment information to another wireless communication device.

[0224] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving configuration information from a node of the wireless communication network (e.g., from an access node serving the wireless communication device or an access node serving another wireless communication device) and determining at least a portion of the DRX configuration based on the configuration information received from the node of the wireless communication network (e.g., configuration information 801, 912, or 1001).

[0225] In some scenarios, the alignment in step 1420 may involve the wireless communication device receiving configuration information from a node of the wireless communication network (e.g., from an access node serving the wireless communication device or an access node serving another wireless communication device) and determining the DRX configuration for communicating with the DL or UL of the wireless communication network based on the received configuration information (e.g., configuration information 801, 1001).

[0226] In some scenarios, the alignment in step 1420 may involve the wireless communication device sending an acknowledgment indicating whether the received configuration information is accepted in response to receiving configuration information.

[0227] In each of the examples above using configuration information, the configuration information may indicate at least a portion of the DRX configuration for D2D communication in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration for DL ​​or UL communication with the wireless communication network. Furthermore, the configuration information may indicate at least a portion of the DRX configuration by identifying one of a plurality of pre-configured (e.g., pre-configured based on standards, operator settings, or network configuration) DRX configurations.

[0228] At least one timer may include at least one first timer for controlling the wireless communication device to be in an active mode of receiving with D2D transmission enabled (e.g., during DRX active time) when the first timer has not expired. Examples of at least one first timer include the timers mentioned above: drx-onDurationTimerSL, drx-InactivityTimerSL, drx-RetransmissionTimerSL, drx-HARQ-FB-TimerSL, drx-CSIReport-TimerSL, and drx-BlindRetransmissionTimerSL.

[0229] In some scenarios, at least one timer may include a retransmission timer that is activated in response to an incoming D2D transmission received by the wireless communication device failing to be successfully decoded.

[0230] In some scenarios, at least one timer may include a feedback timer that is activated in response to an outgoing D2D transmission sent by the wireless communication device (which requires acknowledgment feedback from another wireless communication device).

[0231] In some scenarios, at least one first timer may include a report timer that is activated in response to the wireless communication device sending an outgoing D2D transmission that triggers a measurement report from another wireless communication device.

[0232] At step 1430, the wireless communication device participates in D2D communication with another wireless communication device. For example, the wireless communication device may receive at least one D2D transmission from the other wireless communication device during the DRX activity time determined by the aligned DRX configuration, or the wireless communication device may send at least one D2D transmission to the other wireless communication device during the DRX activity time determined by the aligned DRX configuration.

[0233] Figure 15 The illustration is shown according to Figure 14The block diagram illustrates the functionality of the wireless communication device 1300 operated by the method described above. The wireless communication device 1500 may correspond, for example, to any of the UEs mentioned above. As shown, the wireless communication device 1500 may be provided with a module 1510 configured to determine a DRX configuration for D2D communication with another wireless communication device (as described in conjunction with step 1410). Furthermore, the wireless communication device 1500 may be provided with a module 1520 configured to align the DRX configuration with that of the other wireless communication device (as described in conjunction with step 1420). Additionally, the wireless communication device 1300 may be provided with a module 1530 configured to receive at least one D2D transmission or transmit at least one D2D transmission (as described in conjunction with step 1440).

[0234] Note that the wireless communication device 1500 may include other modules for implementing other functions (such as known functions of the UE in LTE and / or NR radio technologies). Furthermore, note that the modules of the wireless communication device 1500 do not necessarily represent the hardware structure of the wireless communication device 1500, but may also correspond to functional elements (e.g., implemented by hardware, software, or a combination thereof).

[0235] Figure 16 A flowchart illustrating the methods that can be used to implement the concepts described is shown. Figure 16 The method can be used to implement the illustrated concept in nodes of a wireless communication network (e.g., corresponding to any of the access nodes mentioned above).

[0236] If a node-based processor-based implementation is used, then Figure 16 At least some steps of the method can be executed and / or controlled by one or more processors of the node. Such a node may also include storage for implementing at least some of the steps described below. Figure 16 The memory of the program code containing the function or steps of the method.

[0237] At step 1610, the node can control at least one of the first wireless communication device and the second wireless communication device. In some scenarios, the wireless communication devices may each be vehicles or in-vehicle devices, but other types of WDs, such as those mentioned above, may also be used. The node may be an access node serving at least one of the first and second wireless communication devices.

[0238] At step 1620, the node can receive or transmit control information. The node can receive control information from another node in the wireless communication network, for example, using control information 811 or 911. Furthermore, the node can receive control from a first and / or second wireless communication device, for example, using control information 803, 903, or 1103. The node can transmit control information to another node in the wireless communication network, for example, using control information 811 or 911. Furthermore, the node can transmit control to the first and / or second wireless communication device, for example, using control information 801, 812, 814, 912, 914, or 1001.

[0239] At step 1630, the node aligns the first and second wireless communication devices for D2D communication configuration between them. D2D communication may correspond, for example, to SL communication via a PC5 interface using LTE or NR technology. The DRX configuration may correspond, for example, to the SL DRX configuration to be applied by the RXUE mentioned above. D2D communication may involve one of the first and second wireless communication devices receiving at least one D2D communication transmitted by the other of the first and second wireless communication devices.

[0240] The alignment in step 1630 can be based on the configuration information received or transmitted at step 1620. The alignment in step 1630 can prevent one of the first and second wireless communication devices from sending D2D transmissions to the other, while ensuring that, according to the aligned DRX configuration, the other wireless communication device is not in an active mode for receiving D2D transmissions, for example, not during DRX active time.

[0241] The alignment in step 1630 may be performed, for example, with respect to the duration of at least one timer and / or parameters used to derive the duration of at least one timer. At least one timer may include at least one timer for controlling the wireless communication device to be in an active mode of receiving with D2D transmission enabled (e.g., during DRX active time) when a first timer has not expired. Examples of at least one first timer include the aforementioned timers drx-onDurationTimerSL, drx-InactivityTimerSL, drx-RetransmissionTimerSL, drx-HARQ-FB-TimerSL, drx-CSIReport-TimerSL, and drx-BlindRetransmissionTimerSL. In some scenarios, at least one timer may include a retransmission timer that is started in response to an incoming D2D transmission received by the wireless communication device not being successfully decoded. In some scenarios, at least one timer may include a feedback timer that is started in response to an outgoing D2D transmission sent by the wireless communication device (requiring acknowledgment feedback from another wireless communication device). In some scenarios, at least one first timer may include a report timer that is activated in response to an outgoing D2D transmission sent by a wireless communication device, which triggers a measurement report from another wireless communication device.

[0242] The alignment in step 1630 may involve the node determining at least a portion of configuration information for DRX configuration and indicating the determined configuration information to the first wireless communication device and / or the second wireless communication device. Alternatively or additionally, the node may determine at least a portion of configuration information for DRX configuration and indicate the determined configuration information to at least one other node in the wireless communication network. The node may determine at least a portion of the configuration information based on configuration information received from at least one of the first and second wireless communication devices, or based on configuration information received from another node in the wireless communication network. Therefore, the node may also forward configuration information from one wireless communication device to another, or may forward received configuration information to another node.

[0243] Furthermore, the alignment in step 1630 may involve the node sending an acknowledgment message indicating whether the received configuration information is accepted in response to receiving configuration information from at least one of the first and second wireless communication devices.

[0244] Furthermore, the alignment in step 1630 may involve the node determining at least a portion of the configuration information based on the DRX configuration for communicating with at least one of the first and second wireless communication devices via DL or UL.

[0245] Furthermore, the alignment in step 1630 may involve the node determining at least a portion of the configuration information based on the characteristics of the D2D communication between the first wireless communication device and the second wireless communication device (e.g., based on whether HARQ feedback or other confirmation feedback is required).

[0246] Furthermore, the alignment in step 1630 may involve receiving confirmation information indicating whether the configuration information determined by the instruction is accepted in response to the configuration information determined by the instruction.

[0247] Furthermore, the alignment in step 1630 may involve the node declaring a failure of the D2D link between the first and second wireless communication devices in response to the confirmation message indicating that the configuration information determined is not accepted. In some cases, the alignment in step 1630 may additionally or alternatively involve the node initiating the release or reconfiguration of bearers configured on the D2D link between the wireless communication devices in response to the confirmation message indicating that the configuration information determined is not accepted. For example, the latter variant may be useful if multiple bearers are configured on the D2D link and the unaccepted configuration information relates only to a subset of the bearers.

[0248] The configuration information can indicate at least a portion of the DRX configuration in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration used for downlink or uplink communication with at least one of the wireless communication devices and the second wireless communication. Furthermore, the configuration information can indicate at least a portion of the DRX configuration by identifying one of a plurality of pre-configured DRX configurations.

[0249] Furthermore, the alignment in step 1630 may involve the node receiving at least a portion of configuration information for DRX configuration from at least one of the first wireless communication device or the second wireless communication device, and determining a DRX configuration for DL ​​or UL communication with at least one of the first wireless communication device and the second wireless communication device based on the received configuration information.

[0250] Figure 17 The illustration is shown according to Figure 16The diagram illustrates the functionality of node 1700 in a wireless communication network operated by a method. Node 1700 may, for example, correspond to any of the access nodes mentioned above. As shown, node 1700 may be provided with module 1710, which is configured to control wireless communication devices (as described in conjunction with step 1610). Furthermore, node 1700 may be provided with module 1720, which is configured to receive or transmit control information (as described in conjunction with step 1620). Additionally, node 1700 may be provided with module 1730, which is configured to align wireless communication devices for DRX configurations used for D2D communication (as described in conjunction with step 1640).

[0251] Note that Node 1700 may include other modules for implementing other functions, such as the known functions of the eNB in ​​LTE technology and / or the gNB in ​​NR technology. Furthermore, note that the modules of Node 1700 do not necessarily represent the hardware structure of Node 1700, but may also correspond to functional elements (e.g., implemented by hardware, software, or a combination thereof).

[0252] It should be understood that, in combination Figures 12 to 17 The described functionality may also include, for example, based on Figure 12 Wireless communication devices operated by the method, according to Figure 14 Wireless communication devices operated by the method, and according to Figure 16 The method operates by combining two or more nodes in a system in various ways. Furthermore, the same wireless communication device can implement corresponding... Figure 12 Methods and Figure 14 The function of the method's steps.

[0253] Figure 18 The illustration shows a processor-based implementation of a wireless communication device 1800 that can be used to implement the above concepts. For example, as Figure 18 The structures shown can be used to implement these concepts in any of the UEs mentioned above.

[0254] As shown in the figure, the wireless communication device 1800 includes one or more radio interfaces 1810. The radio interface 1810 may be based on NR or LTE technology, for example. The radio interface 1810 may support D2D communication, for example, using SL communication as specified for NR or LTE technology.

[0255] Furthermore, the wireless communication device 1800 may include one or more processors 1850 coupled to a radio interface 1810 and a memory 1860 coupled to the processor 1850. For example, the radio interface 1810, processor 1850, and memory 1860 may be coupled via one or more internal bus systems of the wireless communication device 1800. The memory 1860 may include read-only memory (ROM) (e.g., flash ROM), random access memory (RAM) (e.g., dynamic RAM (DRAM) or static RAM (SRAM)), mass storage devices (e.g., hard disk or solid-state drive), etc. As shown, the memory 1860 may include software 1870 and / or firmware 1880. The memory 1860 may include appropriately configured program code to be executed by the processor 1850 to implement the functions described above for controlling D2D communication (such as combining...). Figures 12 to 15 (As explained).

[0256] It should be understood that Figure 18 The structures shown are merely illustrative, and the wireless communication device 1800 may actually include other components (not shown for clarity, such as other interfaces like a dedicated management interface, or other processors). Furthermore, it should be understood that the memory 1860 may include additional program code for implementing known functions of the UE. According to some embodiments, a computer program may also be provided to implement the functions of the wireless communication device 1800, for example, in the form of a physical medium storing the program code and / or other data to be stored in the memory 1860, or by making the program code available for download or streaming.

[0257] Figure 19 The illustration shows a processor-based implementation of node 1900 for a wireless communication network, which can be used to implement the above concepts. For example, as... Figure 19 The structure shown can be used to implement these concepts in any of the access nodes mentioned above.

[0258] As shown in the figure, node 1900 may include one or more radio interfaces 1910. Radio interfaces 1910 may be based on NR or LTE technology, for example. Radio interfaces 1910 can be used to control wireless communication devices, such as any of the UEs mentioned above. Furthermore, node 1900 may include one or more network interfaces 1920. Network interfaces 1920 can be used, for example, to communicate with one or more other nodes in a wireless communication network. Network interfaces 1920 can also be used to control wireless communication devices, such as any of the UEs mentioned above.

[0259] Furthermore, node 1900 may include one or more processors 1950 coupled to interfaces 1910 and 1920, and memory 1960 coupled to processor 1950. For example, interface 1910, processor 1950, and memory 1960 may be coupled via one or more internal bus systems of node 1900. Memory 1960 may include ROM (e.g., flash ROM), RAM (e.g., DRAM or SRAM), mass storage devices (e.g., hard disk or solid-state drive), etc. As shown, memory 1960 may include software 1970 and / or firmware 1980. Memory 1960 may include appropriately configured program code to be executed by processor 1950 to implement the functions described above for controlling D2D communication (such as in combination with...). Figure 16 and Figure 17 (As explained).

[0260] It should be understood that Figure 19 The structure shown is merely illustrative, and node 1900 may actually include other components (not shown for clarity, such as other interfaces like a dedicated management interface, or other processors). Furthermore, it should be understood that memory 1960 may include additional program code for implementing known functions of an eNB or gNB. According to some embodiments, a computer program may also be provided to implement the functionality of node 1900, for example, in the form of a physical medium storing program code and / or other data to be stored in memory 1960, or by making the program code available for download or streaming.

[0261] As can be seen, the concepts described above can be used to perform D2D communication in an energy-efficient manner. In particular, considering SL transmission and reception characteristics (such as anticipated HARQ feedback transmissions, data retransmissions, and CSI report transmissions), these concepts can be used when an SL UE is configured to wake up for DRX operation. Furthermore, based on the signaling procedures and mechanisms shown herein, SL DRX configurations can be correctly configured and aligned between peer UEs participating in SL communication. Additionally, aligning the SL DRX and DL / UL DRX configurations of the UEs is also possible. This enables efficient management of battery consumption, as the UE can shut down at least a portion of its receive circuitry when no transmission or reception is expected.

[0262] It should be understood that the examples and embodiments described above are merely illustrative and are readily subject to various modifications. For example, the illustrated concepts can be applied in conjunction with various radio technologies (e.g., WLAN technology or other wireless ad hoc network technologies) and D2D communication applications, and are not limited to NR technology or LTE technology in SL mode. Furthermore, these concepts can be applied to various types of UEs, and are not limited to vehicle-based UEs. Moreover, these concepts can be applied in conjunction with various services supported by D2D communication, and are not limited to V2X, NSPS, or NCIS. Furthermore, it should be understood that the above concepts can be implemented using appropriately designed software (to be executed by one or more processors of existing devices or apparatuses), or by using dedicated device hardware. Additionally, it should be noted that the illustrated apparatus or devices can each be implemented as a single device or as a system of multiple interacting devices or modules.

[0263] Accordingly, the embodiments provided in this disclosure include:

[0264] Example 1:

[0265] A method for controlling device-to-device D2D communication, the method comprising:

[0266] The wireless communication device (10; 1300; 1800) determines a discontinuous reception DRX configuration for D2D communication, the DRX configuration being based on at least one timer maintained by the wireless communication device (10; 1300; 1800);

[0267] The wireless communication device controls at least one timer based on at least one D2D transmission between the wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800); and

[0268] Based on this DRX configuration, a wireless communication device (10; 1300; 1800) receives at least one D2D transmission from another wireless communication device (10; 1300; 1500; 1800).

[0269] Example 2:

[0270] The method according to Example 1 includes:

[0271] Wherein, at least one timer includes at least one first timer, which is used to control the wireless communication device (10; 1300; 1800) to be in an active mode of receiving with D2D transmission enabled when the first timer has not expired.

[0272] Example 3:

[0273] The method according to Example 2 includes:

[0274] At least one of the first timers includes a retransmission timer that is activated in response to an incoming D2D transmission received by the wireless communication device (10; 1300; 1800) failing to be decoded.

[0275] Example 4:

[0276] According to the method described in Example 3

[0277] Among them, incoming D2D transmission requires confirmation feedback.

[0278] Example 5:

[0279] The method according to Example 4 includes:

[0280] The wireless communication device (10; 1300; 1800) starts a retransmission timer in response to the expiration of a second timer, which is in response to receiving an incoming D2D transmission and is associated with the round-trip time of an acknowledgment feedback.

[0281] Example 6:

[0282] The method according to embodiment 4 or 5 includes:

[0283] Based on the scheduling mode associated with the incoming D2D transmission, the wireless communication device (10; 1300; 1800) selectively decides whether to start the retransmission timer.

[0284] Example 7:

[0285] According to the method described in Example 3

[0286] In particular, no confirmation feedback is required for incoming D2D transmission.

[0287] Example 8:

[0288] The method according to Example 7 includes:

[0289] The wireless communication device (10; 1300; 1800) starts a retransmission timer in response to the expiration of a second timer, which is started in response to the receipt of an incoming D2D transmission and is associated with the timing of the expected blind retransmission of the incoming D2D.

[0290] Example 9:

[0291] The method according to Example 8 includes:

[0292] The wireless communication device (10; 1300; 1800) determines the duration of the second timer based on the time gap between subsequent reservations made by another wireless communication device (10; 1300; 1500; 1800) for the set of radio resources used for D2D communication.

[0293] Example 10:

[0294] The method according to Example 7 includes:

[0295] After receiving an incoming D2D transmission, the wireless communication device starts a retransmission timer in response to the expiration of the configured time interval.

[0296] Example 11:

[0297] The method according to any one of Examples 7 to 10 includes:

[0298] The wireless communication device (10; 1300; 1800) determines the duration of the retransmission timer based on at least one of the following: control information associated with the incoming D2D transmission, the maximum duration of the retransmission associated with the incoming D2D transmission, and the maximum number of retransmissions associated with the incoming D2D transmission.

[0299] Example 12:

[0300] The method according to any one of Examples 4 to 11 includes:

[0301] The wireless communication device (10; 1300; 1800) stops the retransmission timer in response to successful decoding of a retransmission associated with an incoming D2D transmission.

[0302] Example 13:

[0303] According to the method of any one of Examples 2 to 12,

[0304] At least one of the first timers includes a feedback timer that is activated in response to an outgoing D2D transmission sent by a wireless communication device (10; 1300; 1800) and requires acknowledgment feedback from another wireless communication device.

[0305] Example 14:

[0306] The method according to Example 13 includes:

[0307] The wireless communication device starts a feedback timer in response to the expiration of a second timer, which is started in response to the transmission of an outgoing D2D transmission and is associated with the round-trip time of the acknowledgment feedback.

[0308] Example 15:

[0309] The method according to embodiment 13 or 14 includes:

[0310] The wireless communication device (10; 1300; 1800) determines the duration of the second timer based on the processing capability of another wireless communication device (10; 1300; 1500; 1800).

[0311] Example 16:

[0312] The method according to any one of Examples 13 to 15 includes:

[0313] The wireless communication device (10; 1300; 1800) determines the duration of the second timer based on the periodicity of the radio resources used to send acknowledgment feedback.

[0314] Example 17:

[0315] The method according to any one of Examples 13 to 16 includes:

[0316] The wireless communication device (10; 1300; 1800) stops the feedback timer in response to successfully receiving acknowledgment feedback for outgoing D2D transmission.

[0317] Example 18:

[0318] According to the method of any one of Examples 2 to 17,

[0319] At least one of the first timers includes a report timer that is activated in response to an outgoing D2D transmission sent by a wireless communication device (10; 1300; 1800), which triggers a measurement report from another wireless communication device (10; 1300; 1500; 1800).

[0320] Example 19:

[0321] The method according to Example 18 includes:

[0322] The wireless communication device (10; 1300; 1800) starts a report timer in response to the expiration of a second timer, which is started in response to the transmission of an outgoing D2D transmission and is associated with the round-trip time of the measurement report.

[0323] Example 20:

[0324] The method according to embodiment 18 or 19 includes:

[0325] The wireless communication device (10; 1300; 1800) stops the reporting timer in response to successfully receiving a measurement report.

[0326] Example 21:

[0327] The method according to any one of Examples 1 to 20 includes:

[0328] The wireless communication devices (10; 1300; 1800) align the DRX configuration with another wireless communication device (10; 1300; 1500; 1800).

[0329] Example 22:

[0330] According to the method described in Example 21,

[0331] The alignment DRX configuration includes:

[0332] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0333] The wireless communication device instructs another wireless communication device (10; 1300; 1500; 1800) to indicate the determined configuration information.

[0334] Example 23:

[0335] According to the method described in Example 22,

[0336] The wireless communication device indicates the determined configuration information by transmitting D2D data to another wireless communication device (10; 1300; 1500; 1800).

[0337] Example 24:

[0338] According to the method described in Example 23,

[0339] The determined configuration information is indicated by the following items transmitted via D2D transmission to another wireless communication device (10; 1300; 1500; 1800): Radio Resource Control (RRC) information, Media Access Control (MAC) information, and / or Physical Layer Control information.

[0340] Example 25:

[0341] According to the method described in Examples 21 to 24

[0342] The alignment DRX configuration includes:

[0343] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0344] The wireless communication device (10; 1300; 1800) indicates the determined configuration information to the node (100; 1700; 1900) of the wireless communication network associated with the other wireless communication device.

[0345] Example 26:

[0346] According to the method described in Example 25,

[0347] Among them, the node (100; 1700; 1900) associated with another wireless communication device (10; 1300; 1500; 1800) is an access node that serves the other wireless communication device (10; 1300; 1500; 1800).

[0348] Example 27:

[0349] According to the method of any one of Examples 21 to 26,

[0350] The alignment DRX configuration includes:

[0351] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0352] The wireless communication device (10; 1300; 1800) indicates the determined configuration information to the node (100; 1700; 1900) of the wireless communication network to which the wireless communication device (10; 1300; 1800) is associated.

[0353] Example 28:

[0354] According to the method described in Example 27

[0355] Among them, the nodes (100; 1700; 1900) associated with the wireless communication device (10; 1300; 1800) are the access nodes that serve the wireless communication device (10; 1300; 1800).

[0356] Example 29:

[0357] According to the method of any one of Examples 22 to 28,

[0358] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information based on the configuration information received from the nodes (100; 1700; 1900) of the wireless communication network.

[0359] Example 30:

[0360] According to the method of any one of Examples 22 to 29,

[0361] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information based on the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0362] Example 31:

[0363] According to the method of any one of Examples 22 to 30,

[0364] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information based on the characteristics of D2D communication between the wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0365] Example 32:

[0366] The method according to any one of Examples 22 to 31 includes:

[0367] In response to the configuration information determined by the indication, the wireless communication device (10; 1300; 1800) receives confirmation information indicating whether the configuration information determined by the indication has been accepted.

[0368] Example 33:

[0369] The method according to embodiment 32 includes:

[0370] In response to the confirmation message indicating that the configuration information determined is not accepted, the wireless communication device (10; 1300; 1800) declares the failure of the D2D link between the wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800), or the wireless communication device (10; 1300; 1800) initiates the release or reconfiguration of the bearer configured on the D2D link between the wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0371] Example 34:

[0372] According to the method of any one of Examples 21 to 33,

[0373] The alignment DRX configuration includes:

[0374] Wireless communication devices (10; 1300; 1800) receive configuration information from another wireless communication device (10; 1300; 1500; 1800); and

[0375] The wireless communication device (10; 1300; 1800) determines at least a portion of the DRX configuration based on configuration information received from another wireless communication device (10; 1300; 1500; 1800).

[0376] Example 35:

[0377] According to the method of any one of Examples 21 to 34,

[0378] The alignment DRX configuration includes:

[0379] Wireless communication devices (10; 1300; 1800) receive configuration information from another wireless communication device (10; 1300; 1500; 1800); and

[0380] Based on the received configuration information, the wireless communication device (10; 1300; 1800) determines the DRX configuration for downlink or uplink communication with the wireless communication network.

[0381] Example 36:

[0382] The method described according to Example 34 or 35

[0383] The configuration information received from another wireless communication device (10; 1300; 1500; 1800) is based on D2D transmission received from that other wireless communication device.

[0384] Example 37:

[0385] According to the method described in Example 36

[0386] The received configuration information is indicated by the following items transmitted via D2D transmission from another wireless communication device (10; 1300; 1500; 1800): RRC control information, MAC control information, and / or physical layer control information.

[0387] Example 38:

[0388] According to the method of any one of Examples 21 to 37,

[0389] The alignment DRX configuration includes:

[0390] Wireless communication devices (10; 1300; 1800) receive configuration information from nodes (100; 1700; 1900) of the wireless communication network; and

[0391] The wireless communication device (10; 1300; 1800) determines at least a portion of the DRX configuration based on configuration information received from nodes (100; 1700; 1900) of the wireless communication network.

[0392] Example 39:

[0393] According to the method of any one of Examples 21 to 38,

[0394] The alignment DRX configuration includes:

[0395] Wireless communication devices (10; 1300; 1800) receive configuration information from nodes (100; 1700; 1900) of the wireless communication network; and

[0396] Based on the received configuration information, the wireless communication device (10; 1300; 1800) determines the DRX configuration for downlink or uplink communication with the wireless communication network.

[0397] Example 40:

[0398] The method according to embodiment 38 or 39

[0399] Among them, the nodes (100; 1700; 1900) that receive configuration information are the access nodes that serve the wireless communication devices (10; 1300; 1800).

[0400] Example 41:

[0401] According to the method of any one of Examples 38 to 40,

[0402] Among them, the nodes (100; 1700; 1900) that receive configuration information are access nodes that serve another wireless communication device (10; 1300; 1500; 1800).

[0403] Example 42:

[0404] The method according to any one of Examples 34 to 41 includes:

[0405] In response to receiving configuration information, the wireless communication device (10; 1300; 1800) sends an acknowledgment indicating whether the received configuration information has been accepted.

[0406] Example 43:

[0407] According to any one of Examples 22 to 42,

[0408] The configuration information indicates at least a portion of the DRX configuration in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0409] Example 44:

[0410] According to any one of Examples 22 to 44,

[0411] The configuration information indicates at least a portion of the DRX configuration by identifying one of a plurality of pre-configured DRX configurations.

[0412] Example 45:

[0413] According to any one of Examples 21 to 44,

[0414] The alignment DRX configuration includes:

[0415] The wireless communication device (10; 1300; 1800) determines at least a portion of the DRX configuration based on the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0416] Example 46:

[0417] According to the method of any one of Examples 21 to 45,

[0418] The wireless communication device (10; 1300; 1800) determines at least a portion of the DRX configuration based on the characteristics of the D2D communication between the wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0419] Example 47:

[0420] According to the method of any one of Examples 21 to 46,

[0421] The aligned DRX configuration causes another wireless communication device (10; 1300; 1500; 1800) to avoid sending D2D transmissions to the wireless communication device (10; 1300; 1800), while the wireless communication device (10; 1300; 1800) is not in an active mode of receiving D2D transmissions enabled, depending on the aligned DRX configuration.

[0422] Example 48:

[0423] According to the method of any one of Examples 21 to 47,

[0424] The DRX configuration is aligned for the duration of at least one timer and / or for parameters used to derive the duration of at least one timer.

[0425] Example 49:

[0426] A method for controlling device-to-device D2D communication, the method comprising:

[0427] The wireless communication device (10; 1300; 1500; 1800) determines the discontinuous reception DRX configuration for D2D communication;

[0428] The wireless communication devices (10; 1300; 1500; 1800) align this DRX configuration with another wireless communication device (10; 1300; 1500; 1800); and

[0429] Based on this DRX configuration, wireless communication devices (10; 1300; 1500; 1800) participate in D2D communication with another wireless communication device (10; 1300; 1500; 1800).

[0430] Example 50:

[0431] According to the method described in Example 49

[0432] The alignment DRX configuration includes:

[0433] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0434] Wireless communication device (10; 1300; 1500; 1800) instructs another wireless communication device (10; 1300; 1500; 1800) on the determined configuration information.

[0435] Example 51:

[0436] According to the method described in Example 50,

[0437] The wireless communication devices (10; 1300; 1500; 1800) indicate the determined configuration information by transmitting D2D data to another wireless communication device (10; 1300; 1500; 1800).

[0438] Example 52:

[0439] According to the method described in Example 51,

[0440] The determined configuration information is indicated by the following items transmitted via D2D transmission to another wireless communication device (10; 1300; 1500; 1800): Radio Resource Control (RRC) information, Media Access Control (MAC) information, and / or Physical Layer Control information.

[0441] Example 53:

[0442] The method described according to Examples 49 to 52

[0443] The alignment DRX configuration includes:

[0444] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0445] The wireless communication device (10; 1300; 1500; 1800) indicates the determined configuration information to the node (100; 1700; 1900) of the wireless communication network associated with another wireless communication device (10; 1300; 1500; 1800).

[0446] Example 54:

[0447] According to the method described in Example 53,

[0448] Among them, the node (100; 1700; 1900) associated with another wireless communication device (10; 1300; 1500; 1800) is an access node that serves the other wireless communication device (10; 1300; 1500; 1800).

[0449] Example 55:

[0450] According to any one of Examples 49 to 54, the method is as follows

[0451] The alignment DRX configuration includes:

[0452] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the configuration information used for the DRX configuration; and

[0453] The wireless communication device (10; 1300; 1500; 1800) indicates the determined configuration information to the node (100; 1700; 1900) of the wireless communication network associated with the wireless communication device (10; 1300; 1500; 1800).

[0454] Example 56:

[0455] According to the method described in Example 55,

[0456] Among them, the nodes (100; 1700; 1900) associated with the wireless communication device (10; 1300; 1500; 1800) are the access nodes that serve the wireless communication device (10; 1300; 1500; 1800).

[0457] Example 57:

[0458] According to the method of any one of Examples 50 to 55,

[0459] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the configuration information based on the configuration information received from the nodes (100; 1700; 1900) of the wireless communication network.

[0460] Example 58:

[0461] According to the method of any one of Examples 50 to 57,

[0462] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the configuration information based on the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0463] Example 59:

[0464] According to the method of any one of Examples 50 to 58,

[0465] The wireless communication device (10; 1300; 1800) determines at least a portion of the configuration information based on the characteristics of D2D communication between the wireless communication device (10; 1300; 1500; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0466] Example 60:

[0467] The method according to any one of Examples 49 to 57 includes:

[0468] In response to the configuration information determined by the indication, the wireless communication device (10; 1300; 1500; 1800) receives confirmation information indicating whether the configuration information determined by the indication is accepted.

[0469] Example 61:

[0470] The method according to Example 60 includes:

[0471] In response to the confirmation message indicating that the configuration information determined is not accepted, the wireless communication device (10; 1300; 1500; 1800) declares the failure of the D2D link between the wireless communication device (10; 1300; 1500; 1800) and another wireless communication device (10; 1300; 1500; 1800), or the wireless communication device (10; 1300; 1500; 1800) initiates the release or reconfiguration of the bearer configured on the D2D link between the wireless communication device (10; 1300; 1500; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0472] Example 62:

[0473] According to the method described in any one of Examples 49 to 61,

[0474] The alignment DRX configuration includes:

[0475] Wireless communication devices (10; 1300; 1500; 1800) receive configuration information from another wireless communication device (10; 1300; 1500; 1800); and

[0476] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the DRX configuration based on configuration information received from another wireless communication device (10; 1300; 1500; 1800).

[0477] Example 63:

[0478] According to the method described in any one of Examples 49 to 62,

[0479] The alignment DRX configuration includes:

[0480] Wireless communication devices (10; 1300; 1500; 1800) receive configuration information from another wireless communication device (10; 1300; 1500; 1800); and

[0481] Based on the received configuration information, the wireless communication device (10; 1300; 1500; 1800) determines the DRX configuration for downlink or uplink communication with the wireless communication network.

[0482] Example 64:

[0483] The method described according to embodiment 62 or 63

[0484] The configuration information received from another wireless communication device (10; 1300; 1500; 1800) is based on the D2D transmission received from that other wireless communication device (10; 1300; 1500; 1800).

[0485] Example 65:

[0486] According to the method described in Example 64

[0487] The received configuration information is indicated by the following items transmitted via D2D transmission from another wireless communication device (10; 1300; 1500; 1800): RRC control information, MAC control information, and / or physical layer control information.

[0488] Example 66:

[0489] According to the method of any one of Examples 49 to 65,

[0490] The alignment DRX configuration includes:

[0491] Wireless communication devices (10; 1300; 1500; 1800) receive configuration information from nodes (100; 1700; 1900) of the wireless communication network; and

[0492] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the DRX configuration based on configuration information received from nodes (100; 1700; 1900) of the wireless communication network.

[0493] Example 67:

[0494] According to the method described in any one of Examples 49 to 66,

[0495] The alignment DRX configuration includes:

[0496] Wireless communication devices (10; 1300; 1500; 1800) receive configuration information from nodes (100; 1700; 1900) of the wireless communication network; and

[0497] Based on the received configuration information, the wireless communication device (10; 1300; 1500; 1800) determines the DRX configuration for downlink or uplink communication with the wireless communication network.

[0498] Example 68:

[0499] The method described according to Example 66 or 67

[0500] Among them, the nodes (100; 1700; 1900) that receive configuration information are access nodes that serve wireless communication devices (10; 1300; 1500; 1800).

[0501] Example 69:

[0502] According to the method of any one of Examples 66 to 68,

[0503] Among them, the nodes (100; 1700; 1900) that receive configuration information are access nodes that serve another wireless communication device (10; 1300; 1500; 1800).

[0504] Example 70:

[0505] The method according to any one of Examples 63 to 69 includes:

[0506] In response to receiving configuration information, the wireless communication device (10; 1300; 1500; 1800) sends an acknowledgment indicating whether the received configuration information has been accepted.

[0507] Example 71:

[0508] According to the method of any one of Examples 50 to 70,

[0509] The configuration information indicates at least a portion of the DRX configuration in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0510] Example 72:

[0511] According to the method of any one of Examples 50 to 71,

[0512] The configuration information indicates at least a portion of the DRX configuration by identifying one of a plurality of pre-configured DRX configurations.

[0513] Example 73:

[0514] According to the method described in any one of Examples 49 to 72,

[0515] The alignment DRX configuration includes:

[0516] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the DRX configuration based on the DRX configuration used for downlink or uplink communication with the wireless communication network.

[0517] Example 74:

[0518] According to any one of Examples 49 to 73, the method

[0519] The wireless communication device (10; 1300; 1500; 1800) determines at least a portion of the DRX configuration based on the characteristics of D2D communication between the wireless communication device (10; 1300; 1500; 1800) and another wireless communication device (10; 1300; 1500; 1800).

[0520] Example 75:

[0521] According to the method of any one of Examples 49 to 74

[0522] The aligned DRX configuration causes another wireless communication device (10; 1300; 1500; 1800) to avoid sending D2D transmissions to the other wireless communication device (10; 1300; 1500; 1800), and according to the aligned DRX configuration, the other wireless communication device (10; 1300; 1500; 1800) is not in a receiving mode that enables D2D transmission, and / or causes the other wireless communication device (10; 1300; 1500; 1800) to avoid sending D2D transmissions to the other wireless communication device (10; 1300; 1500; 1800), and according to the aligned DRX configuration, the other wireless communication device (10; 1300; 1500; 1800) is not in a receiving mode that enables D2D transmission.

[0523] Example 76:

[0524] A method for controlling device-to-device D2D communication, the method comprising:

[0525] The nodes (100; 1700; 1900) of the wireless communication network are configured for discontinuous reception (DRX) of D2D communication between the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800), and are aligned with the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device.

[0526] Example 77:

[0527] According to the method described in Example 76

[0528] The alignment includes:

[0529] Nodes (100; 1700; 1900) determine at least a portion of the configuration information used for DRX configuration; and

[0530] The node (100; 1700; 1900) indicates the determined configuration information to at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device.

[0531] Example 78:

[0532] The method described according to embodiment 76 or 77

[0533] The alignment includes:

[0534] Nodes (100; 1700; 1900) determine at least a portion of the configuration information used for DRX configuration; and

[0535] Nodes (100; 1700; 1900) indicate the determined configuration information to at least one other node (100; 1700; 1900) in the wireless communication network.

[0536] Example 79:

[0537] According to the method described in any one of Examples 76 to 78,

[0538] Nodes (100; 1700; 1900) are access nodes serving at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0539] Example 80:

[0540] According to the method described in any one of Examples 76 to 79,

[0541] Nodes (100; 1700; 1900) determine at least a portion of the configuration information based on configuration information received from at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0542] Example 81:

[0543] The method according to Example 80 includes:

[0544] In response to receiving configuration information from at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800), the node (100; 1700; 1900) sends an acknowledgment indicating whether the received configuration information has been accepted.

[0545] Example 82:

[0546] According to the method of any one of Examples 76 to 81,

[0547] Nodes (100; 1700; 1900) determine at least a portion of configuration information based on DRX configuration for downlink or uplink communication with at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0548] Example 83:

[0549] According to the method of any one of Examples 76 to 82,

[0550] Among them, nodes (100; 1700; 1900) determine at least a portion of the configuration information based on the characteristics of D2D communication between the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0551] Example 84:

[0552] The method according to any one of embodiments 76 to 83 includes:

[0553] In response to the configuration information determined by the indication, the nodes (100; 1700; 1900) receive confirmation information indicating whether the configuration information determined by the indication is accepted.

[0554] Example 85:

[0555] The method according to Example 84 includes:

[0556] In response to the confirmation message indicating that the configuration information determined was not accepted, the node (100; 1700; 1900) declares the failure of the D2D link between the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800), or the node (100; 1700; 1900) initiates the release or reconfiguration of the bearer configured on the D2D link between the wireless communication device (10; 1300; 1800) and the other wireless communication device (10; 1300; 1500; 1800).

[0557] Example 86:

[0558] According to the method of any one of Examples 76 to 85,

[0559] The configuration information indicates at least a portion of the DRX configuration in terms of deviations between one or more parameters of the DRX configuration and the DRX configuration used for downlink or uplink communication with at least one of the wireless communication devices (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0560] Example 87:

[0561] According to the method of any one of Examples 76 to 86,

[0562] The alignment includes:

[0563] Nodes (100; 1700; 1900) receive at least a portion of configuration information for DRX configuration from at least one of a first wireless communication device (10; 1300; 1500; 1800) and a second wireless communication device (10; 1300; 1500; 1800); and

[0564] Based on the received configuration information, the node (100; 1700; 1900) determines the DRX configuration for downlink or uplink communication with at least one of the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0565] Example 88:

[0566] According to the method described in any one of Examples 76 to 87,

[0567] The configuration information indicates at least a portion of the DRX configuration by identifying one of a plurality of pre-configured DRX configurations.

[0568] Example 89:

[0569] According to the method of any one of Examples 76 to 88,

[0570] The alignment ensures that one of the first wireless communication devices (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800) avoids sending D2D transmissions to the other wireless communication device, while, according to the aligned DRX configuration, the other wireless communication device (10; 1300; 1500; 1800) is not in an active mode for receiving D2D transmissions.

[0571] Example 90:

[0572] A wireless communication device (10; 1300; 1800) is configured to:

[0573] Determine the discontinuous reception DRX configuration for D2D communication, which is based on at least one timer maintained by the wireless communication device;

[0574] Based on at least one D2D transmission between a wireless communication device (10; 1300; 1800) and another wireless communication device (10; 1300; 1500; 1800), control the at least one timer; and

[0575] Based on this DRX configuration, at least one D2D transmission is received from another wireless communication device (10; 1300; 1500; 1800).

[0576] Example 91:

[0577] According to the wireless communication device (10; 1300; 1800) described in Embodiment 90,

[0578] The wireless communication device (10; 1300; 1800) is configured to perform the method according to any one of embodiments 2 to 48.

[0579] Example 92:

[0580] The wireless communication device (10; 1300; 1800) according to embodiment 90 or 91 includes:

[0581] At least one processor (1850), and

[0582] The memory (1860) contains program code executable by the at least one processor (1850).

[0583] Thus, the at least one processor (1850) executes the program code to cause the wireless communication device (10; 1300; 1800) to perform the method according to any one of embodiments 1 to 48.

[0584] Example 93:

[0585] A wireless communication device (10; 1300; 1500; 1800) is configured to:

[0586] Determine the discontinuous reception DRX configuration for D2D communication;

[0587] Align this DRX configuration with another wireless communication device (10; 1300; 1500; 1800); and

[0588] Based on this DRX configuration, participate in D2D communication with another wireless communication device (10; 1300; 1500; 1800).

[0589] Example 94:

[0590] According to the wireless communication device (10; 1300; 1500; 1800) described in Embodiment 93,

[0591] The wireless communication device (10; 1300; 1500; 1800) is configured to perform the method according to any one of embodiments 50 to 75.

[0592] Example 95:

[0593] The wireless communication device (10; 1300; 1500; 1800) according to embodiment 93 or 94 includes:

[0594] At least one processor (1850), and

[0595] The memory (1860) contains program code executable by the at least one processor (1850).

[0596] Thus, the at least one processor (1850) executes the program code to cause the wireless communication device (10; 1300; 1500; 1800) to perform the method according to any one of embodiments 49 to 75.

[0597] Example 96:

[0598] A node (100; 1700; 1900) for a wireless communication network, the node (100; 1700; 1900) being configured to:

[0599] For discontinuous reception DRX configuration of D2D communication between a first wireless communication device (10; 1300; 1500; 1800) and a second wireless communication device (10; 1300; 1500; 1800), align the first wireless communication device (10; 1300; 1500; 1800) and the second wireless communication device (10; 1300; 1500; 1800).

[0600] Example 97:

[0601] According to the nodes (100; 1700; 1900) described in Example 95,

[0602] The node (100; 1700; 1900) is configured to perform the method according to any one of embodiments 77 to 89.

[0603] Example 98:

[0604] The node (100; 1700; 1900) according to embodiment 95 or 96 includes:

[0605] At least one processor (1950), and

[0606] Memory (1960) containing program code executable by the at least one processor (1950),

[0607] Thus, the at least one processor (1950) executes the program code to cause the node (100; 1700; 1900) to perform the method according to any one of embodiments 76 to 89.

[0608] Example 99:

[0609] A computer program or computer program product comprising program code executable by at least one processor of a wireless communication device (10; 1300; 1500; 1800), wherein execution of the program code causes the wireless communication device (10; 1300; 1500; 1800) to perform the method according to any one of embodiments 1 to 75.

[0610] Example 100:

[0611] A computer program or computer program product comprising program code to be executed by at least one processor of a node (100; 1700; 1900) for a wireless communication network, wherein execution of the program code causes the node (100; 1700; 1900) to perform the method according to any one of embodiments 76 to 89.

Claims

1. A method of controlling device-to-device, D2D, communication, the method comprising: a wireless communication device determining a discontinuous reception, DRX, configuration for D2D communication; the wireless communication device aligning the DRX configuration with another wireless communication device; and based on the DRX configuration, the wireless communication device engaging in D2D communication with the other wireless communication device, wherein the aligning the DRX configuration comprises: the wireless communication device determining configuration information for at least a portion of the DRX configuration; the wireless communication device indicating the determined configuration information to the other wireless communication device; and in response to the indicating the determined configuration information, the wireless communication device receiving confirmation information indicating whether the determined configuration information is accepted.

2. The method of claim 1, the wireless communication device indicating the determined configuration information by a D2D transmission to the other wireless communication device. wherein, 3. The method of claim 2, the determined configuration information is indicated by the D2D transmission to the other wireless communication device by radio resource control, RRC, information, medium access control, MAC, control information, and / or physical layer control information. wherein 4. The method of any of claims 1-3, the wireless communication device determining at least a portion of the configuration information based on a DRX configuration for downlink or uplink communication with a wireless communication network, and / or wherein wherein the wireless communication device determines at least a portion of the configuration information in dependence on a characteristic of D2D communication between the wireless communication device and the other wireless communication device.

5. The method of any of claims 1-3, the confirmation information further indicates an updated DRX configuration for D2D communication. wherein 6. The method of any of claims 1-3, the aligning the DRX configuration comprises: wherein the wireless communication device receiving configuration information from the other wireless communication device; and the wireless communication device determining at least a portion of the DRX configuration based on the configuration information received from the other wireless communication device.

7. The method of any of claims 1-3, the aligning the DRX configuration comprises: wherein the wireless communication device receiving configuration information from the other wireless communication device; based on the received configuration information, the wireless communication device determining a DRX configuration for downlink or uplink communication with a wireless communication network; the wireless communication device forwarding at least a portion of the configuration information received from the other wireless communication device to a node of the wireless communication network; the wireless communication device receiving confirmation information from the node, the confirmation information indicating whether the forwarded configuration information is accepted; and the wireless communication device forwarding the confirmation information to the other wireless communication device.

8. The method of claim 6, the receiving the configuration information from the other wireless communication device is based on a D2D transmission received from the other wireless communication device. wherein 9. The method of claim 8, ​ wherein The received configuration information is indicated by the following being transmitted by the D2D transmission from the other wireless communication device: RRC control information, MAC control information, and / or physical layer control information.

10. The method of any of claims 1 to 3, wherein The configuration information indicates at least a part of the DRX configuration in terms of a deviation of one or more parameters of the DRX configuration from a DRX configuration for downlink or uplink communication with a wireless communication network, and / or wherein the configuration information indicates at least a part of the DRX configuration by identifying one of a plurality of preconfigured DRX configurations.

11. The method of any of claims 1 to 3, wherein The aligning the DRX configuration comprises: The wireless communication device determines at least a part of the DRX configuration based on a DRX configuration for downlink or uplink communication with a wireless communication network, and / or The wireless communication device determines at least a part of the DRX configuration in dependence on a characteristic of a D2D communication between the wireless communication device and the other wireless communication device.

12. The method of any of claims 1 to 3, wherein The wireless communication device is a connected vehicle.

13. A method of controlling device-to-device, D2D, communication, the method comprising: a node of a wireless communication network aligning a first wireless communication device and a second wireless communication device for a discontinuous reception, DRX, configuration for D2D communication between the first wireless communication device and the second wireless communication device, wherein the aligning comprises: the node determining configuration information for at least a part of the DRX configuration; and the node indicating the determined configuration information to at least one of the first wireless communication device and the second wireless communication device; and in response to the indicating the determined configuration information, the node receiving confirmation information indicating whether the determined configuration information is accepted.

14. The method of claim 13, wherein The aligning comprises: the node determining configuration information for at least a part of the DRX configuration; and the node indicating the determined configuration information to at least one other node of the wireless communication network.

15. The method of claim 13 or 14, wherein, The node determines at least a part of the configuration information based on configuration information received from at least one of the first wireless communication device and the second wireless communication device.

16. The method of claim 15, comprising: in response to receiving the configuration information from the at least one of the first wireless communication device and the second wireless communication device, the node sending confirmation information indicating whether the received configuration information is accepted.

17. The method of claim 13 or 14, wherein, The node determines at least a part of the configuration information based on a DRX configuration for downlink or uplink communication with at least one of the first wireless communication device and the second wireless communication device, and / or wherein the node determines at least part of the configuration information based on characteristics of a D2D communication between the first wireless communication device and the second wireless communication device.

18. The method of claim 13 or 14, wherein, the aligning comprises: the node receives configuration information for at least part of the DRX configuration from at least one of the first wireless communication device and the second wireless communication device; and based on the received configuration information, the node determines a DRX configuration for downlink or uplink communication with at least one of the first wireless communication device and the second wireless communication device.

19. The method of claim 13 or 14, wherein the configuration information indicates at least part of the DRX configuration by identifying one of a plurality of preconfigured DRX configurations.

20. A wireless communication device, the wireless communication device comprising: at least one processor, and a memory storing program code executable by the at least one processor, whereby the at least one processor executes the program code to cause the wireless communication device to: determine a discontinuous reception, DRX, configuration for device-to-device, D2D, communication; align the DRX configuration with another wireless communication device; and participate in D2D communication with the other wireless communication device based on the DRX configuration, wherein, for the aligning the DRX configuration, the at least one processor executes the program code to further cause the wireless communication device to: determine configuration information for at least part of the DRX configuration; indicate the determined configuration information to the other wireless communication device; and in response to the indicating the determined configuration information, receive confirmation information indicating whether the determined configuration information is accepted.

21. The wireless communication device of claim 20, the at least one processor executes the program code to further cause the wireless communication device to indicate the determined configuration information by a D2D transmission to the other wireless communication device. wherein, 22. The wireless communication device of claim 21, the determined configuration information is indicated by the D2D transmission to the other wireless communication device by radio resource control, RRC, information, medium access control, MAC, control information, and / or physical layer control information. wherein, 23. The wireless communication device of any of claims 20 to 22, the at least one processor executes the program code to further cause the wireless communication device to: wherein determine at least part of the configuration information based on a DRX configuration for downlink or uplink communication with a wireless communication network, and / or determine at least part of the configuration information based on characteristics of a D2D communication between the wireless communication device and the other wireless communication device.

24. The wireless communication device of any of claims 20 to 22, the confirmation information further indicates an updated DRX configuration for D2D communication. wherein 25. The wireless communication device of any of claims 20 to 22, ​ wherein For said aligning the DRX configuration, the at least one processor executes the program code further to cause the wireless communication device to: receive configuration information from the other wireless communication device; and determine at least part of the DRX configuration based on the configuration information received from the other wireless communication device.

26. The wireless communication device of any of claims 20 to 22, wherein, For said aligning the DRX configuration, the at least one processor executes the program code further to cause the wireless communication device to: receive configuration information from the other wireless communication device; determine a DRX configuration for downlink or uplink communication with a wireless communication network based on the received configuration information; forward at least part of the configuration information received from the other wireless communication device to a node of the wireless communication network; receive confirmation information from the node, the confirmation information indicating whether the forwarded configuration information is accepted; and forward the confirmation information to the other wireless communication device.

27. The wireless communication device of claim 25, wherein said receiving the configuration information from the other wireless communication device is based on a D2D transmission received from the other wireless communication device.

28. The wireless communication device of claim 27, wherein, the received configuration information is indicated by RRC control information, MAC control information, and / or physical layer control information conveyed by the D2D transmission from the other wireless communication device.

29. The wireless communication device of any of claims 20 to 22, wherein, said configuration information indicates at least part of the DRX configuration in terms of one or more parameters of the DRX configuration and a DRX configuration for downlink or uplink communication with a wireless communication network, and / or wherein the configuration information indicates at least part of the DRX configuration by identifying one of a plurality of preconfigured DRX configurations.

30. The wireless communication device of any of claims 20 to 22, wherein, For said aligning the DRX configuration, the at least one processor executes the program code further to cause the wireless communication device to: determine at least part of the DRX configuration based on a DRX configuration for downlink or uplink communication with a wireless communication network, and / or determine at least part of the DRX configuration in dependence on a characteristic of D2D communication between the wireless communication device and the other wireless communication device.

31. The wireless communication device of any of claims 20 to 22, wherein, the wireless communication device is a connected vehicle.

32. A node for a wireless communication network, the node comprising: at least one processor, and a memory storing program code executable by the at least one processor, whereby execution of the program code by the at least one processor causes the node to: receive configuration information from the other wireless communication device; and determine at least part of the DRX configuration based on the configuration information received from the other wireless communication device. aligning, for a discontinuous reception, DRX, configuration for device-to-device, D2D, communication between a first wireless communication device and a second wireless communication device, the first wireless communication device and the second wireless communication device, wherein, for the aligning, the at least one processor executing the program code further causes the node to: determine configuration information for at least a portion of the DRX configuration; and indicate the determined configuration information to at least one of the first wireless communication device and the second wireless communication device; and receive, in response to the indicating the determined configuration information, confirmation information indicating whether the determined configuration information is accepted.

33. The node of claim 32, wherein for the aligning, the at least one processor executing the program code further causes the node to: determine configuration information for at least a portion of the DRX configuration; and indicate the determined configuration information to at least one other node of the wireless communication network.

34. The node of claim 32 or 33, wherein, the at least one processor executing the program code further causes the node to determine at least a portion of the configuration information based on configuration information received from at least one of the first wireless communication device and the second wireless communication device.

35. The node of claim 34, wherein the at least one processor executing the program code further causes the node to, in response to receiving the configuration information from the at least one of the first wireless communication device and the second wireless communication device, send confirmation information indicating whether the received configuration information is accepted.

36. The node of claim 32 or 33, wherein the at least one processor executing the program code further causes the node to: determine at least a portion of the configuration information based on a DRX configuration for downlink or uplink communication with at least one of the first wireless communication device and the second wireless communication device, and / or determine at least a portion of the configuration information in accordance with a characteristic of D2D communication between the first wireless communication device and the second wireless communication device.

37. The node of claim 32 or 33, wherein for the aligning, the at least one processor executing the program code further causes the node to: receive, from at least one of the first wireless communication device and the second wireless communication device, configuration information for at least a portion of the DRX configuration; and determine, based on the received configuration information, a DRX configuration for downlink or uplink communication with at least one of the first wireless communication device and the second wireless communication device.

38. The node of claim 32 or 33, the configuration information indicates at least a portion of the DRX configuration by identifying one of a plurality of preconfigured DRX configurations. wherein, ​ 39. A non-transitory storage medium having stored thereon program code to be executed by at least one processor of a wireless communication device, whereby execution of the program code causes the wireless communication device to perform the method of any of claims 1-12.

40. A non-transitory storage medium having stored thereon program code to be executed by at least one processor of a node for a wireless communication network, whereby execution of the program code causes the node to perform the method of any of claims 13-19.

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