WO2021147006A1

WO2021147006A1 - Sidelink reception alignment

Info

Publication number: WO2021147006A1
Application number: PCT/CN2020/073840
Authority: WO
Inventors: Xiaodong Yu; Zhennian SUN; Ran YUE; Haipeng Lei; Haiming Wang; Xin Guo
Original assignee: Lenovo (Beijing) Limited
Priority date: 2020-01-22
Filing date: 2020-01-22
Publication date: 2021-07-29

Abstract

Methods and apparatuses for sidelink reception alignment are disclosed. A method may comprises receiving, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit; and receiving a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit.

Description

SIDELINK RECEPTION ALIGNMENT

FIELD

The subject matter disclosed herein generally relates to wireless communications, and more particularly relates to sidelink reception alignment.

BACKGROUND

The following abbreviations are herewith defined, at least some of which are referred to within the following description: Third Generation Partnership Project (3GPP) , European Telecommunications Standards Institute (ETSI) , Frequency Division Duplex (FDD) , Frequency Division Multiple Access (FDMA) , Long Term Evolution (LTE) , New Radio (NR) , Very Large Scale Integration (VLSI) , Random Access Memory (RAM) , Read-Only Memory (ROM) , Erasable Programmable Read-Only Memory (EPROM or Flash Memory) , Compact Disc Read-Only Memory (CD-ROM) , Local Area Network (LAN) , Wide Area Network (WAN) , Personal Digital Assistant (PDA) , User Equipment (UE) , Uplink (UL) , Evolved Node B (eNB) , Next Generation Node B (gNB) , New Radio (NR) , Downlink (DL) , Central Processing Unit (CPU) , Graphics Processing Unit (GPU) , Field Programmable Gate Array (FPGA) , Dynamic RAM (DRAM) , Synchronous Dynamic RAM (SDRAM) , Static RAM (SRAM) , Liquid Crystal Display (LCD) , Light Emitting Diode (LED) , Organic LED (OLED) , Next Generation Node B (gNB) , Orthogonal Frequency Division Multiplexing (OFDM) , Radio Resource Control (RRC) , Reference Signal (RS) , Time-Division Duplex (TDD) , Time Division Multiplex (TDM) , User Entity/Equipment (Mobile Terminal) (UE) , Uplink (UL) , Universal Mobile Telecommunications System (UMTS) , Long Term Evolution (LTE) , Narrowband (NB) , Physical Downlink Shared Channel (PDSCH) , Physical Uplink Shared Channel (PUSCH) , Physical Uplink Control Channel (PUCCH) , Downlink control information (DCI) , Universal Mobile Telecommunications System (UMTS) , Evolved-UMTS Terrestrial Radio Access (E-UTRA or EUTRA) , Media Access Control (MAC) , Control Element (CE) , Bandwidth Part (BWP) , Technical specification (TS) , sidelink (SL) , Discontinuous Reception (DRX) , in the coverage of network (IC) , out of coverage of network (OOC) , Sidelink Control Information (SCI) , Physical Sidelink Control Channel (PSCCH) , Radio Network Tempory Identity (RNTI) .

When multiple Tx UEs perform transmissions to the same Rx UE on sidelink, Rx UE may align DRX ON durations among the communication with multiple Tx UEs for the power consumption of Rx UE. For example, in upper part of Figure 1, Tx UE A performs sidelink transmission to Rx UE in the first time period and Tx UE B performs sidelink transmission to Rx UE in the third time period. In the first and the third time periods, Rx UE can be configured or indicated as DRX ON duration during which Rx UE monitors sidelink transmission. In other time periods (the second time period, fourth time period and fifth time period) , Rx UE can be configured or indicated as DRX OFF duration, during which Rx UE does not monitor sidelink transmission for saving power. Basically, Tx UE A and Tx UE B don’ t take full time domain and/or frequency domain resource during each time period (10ms) . That is, Tx UE A and Tx UE B can perform transmission in the same one time period (for example, in the first time period) , as shown in lower part of Figure 1. From the perspective of Rx UE, if the Rx UE can perform reception of transmissions from multiple Tx UEs (e.g. Tx UE A and Tx UE B) in the same time period, it can save power by monitoring all transmissions during a shorter time duration.

It is therefore an object of the present invention to provide methods and apparatuses to implement sidelink reception alignment (e.g. perform reception of sidelink transmissions from different Tx UEs in the same time period) .

BRIEF SUMMARY

Methods and apparatuses for sidelink reception alignment are disclosed.

In one embodiment, a method comprises receiving, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit; and receiving a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit. In one embodiment, the method further comprises monitoring the sidelink transmission according to the activated sidelink reception duration configuration.

In one embodiment, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions

In some embodiment, the downlink control information includes a field to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration. In some embodiment, the downlink control information is scrambled by a RNTI to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration. In some embodiment, the downlink control information includes a field to indicate which sidelink reception duration configuration is activated or deactivated. In another embodiment, the sidelink control information includes a field to indicate that the activated sidelink reception duration configuration is contained in data transmission.

In some embodiment, the method further comprises sending a set of candidate sidelink reception duration configurations to the transmitting remote unit. In particular, the method may further comprise sending a scheduling request for transmitting sidelink reception duration configuration (s) to the base unit; and in response to receiving a grant from the base unit, sending the set of candidate sidelink reception duration configurations to the transmitting remote unit.

In some embodiment, when a plurality of sidelink reception duration configurations are activated, the method further comprises sending a selected activated sidelink reception duration configuration to the transmitting remote unit. In particular, the activated sidelink reception duration configuration is selected based on a larger ON duration among multiple activated configurations, or based on the comparison of priorities among multiple activated configurations, or based on the comparison of cast types of multiple activated configurations.

In one embodiment, a base unit comprises a transmitter configured to transmit, to a receiving remote unit and/or a transmitting remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving unit; and a receiver, wherein in response to the receiver receiving an indication of the sidelink transmission, the transmitter is further configured to transmit, to the receiving remote unit, a downlink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.

In another embodiment, a method comprises transmitting, to a receiving remote unit and/or a transmitting remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving unit; and in response to receiving an indication of the sidelink transmission, transmitting, to the receiving remote unit, a downlink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations

In yet another embodiment, a receiving remote unit comprises a receiver configured to receive, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit, wherein the receiver is further configured to receive a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit.

In a further embodiment, a method comprises receiving, from a base unit and/or a receiving remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to the receiving remote unit; and transmitting, to the receiving remote unit, a sidelink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.

In a yet further embodiment, a transmitting remote unit comprises a receiver configured to receive, from a base unit and/or a receiving remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving remote unit; and a transmitter configured to transmit, to the receiving remote unit, a sidelink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of the embodiments briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only some embodiments, and are not therefore to be considered to be limiting of scope, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:

Figure 1 illustrates an example of conventional sidelink transmission and reception and a desired sidelink transmission and reception;

Figure 2 illustrates an example of a method according to a first embodiment;

Figure 3 illustrates a method of transmitting sidelink (SL) control information from Tx UE;

Figure 4 illustrates a method of transmitting sidelink (SL) control information from Rx UE;

Figure 5 is a schematic flow chart diagram illustrating an embodiment of a method;

Figure 6 is a schematic flow chart diagram illustrating a further embodiment of a method; and

Figure 7 is a schematic flow chart diagram illustrating another embodiment of a method

Figure 8 is a schematic block diagram illustrating apparatuses according to one embodiment.

DETAILED DESCRIPTION

As will be appreciated by one skilled in the art that certain aspects of the embodiments may be embodied as a system, apparatus, method, or program product. Accordingly, embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc. ) or an embodiment combining software and hardware aspects that may generally all be referred to herein as a “circuit” , “module” or “system” . Furthermore, embodiments may take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer readable code, and/or program code, referred to hereafter as “code” . The storage devices may be tangible, non-transitory, and/or non-transmission. The storage devices may not embody signals. In a certain embodiment, the storage devices only employ signals for accessing code.

Certain functional units described in this specification may be labeled as “modules” , in order to more particularly emphasize their independent implementation. For example, a module may be implemented as a hardware circuit comprising custom very-large-scale integration (VLSI) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

Modules may also be implemented in code and/or software for execution by various types of processors. An identified module of code may, for instance, include one or more physical or logical blocks of executable code which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but, may include disparate instructions stored in different locations which, when joined logically together, include the module and achieve the stated purpose for the module.

Indeed, a module of code may contain a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules and may be embodied in any suitable form and organized within any suitable type of data structure. This operational data may be collected as a single data set, or may be distributed over different locations including over different computer readable storage devices. Where a module or portions of a module are implemented in software, the software portions are stored on one or more computer readable storage devices.

Any combination of one or more computer readable medium may be utilized. The computer readable medium may be a computer readable storage medium. The computer readable storage medium may be a storage device storing code. The storage device may be, for example, but need not necessarily be, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

A non-exhaustive list of more specific examples of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, random access memory (RAM) , read-only memory (ROM) , erasable programmable read-only memory (EPROM or Flash Memory) , portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Code for carrying out operations for embodiments may include any number of lines and may be written in any combination of one or more programming languages including an object-oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or the like, and/or machine languages such as assembly languages. The code may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the very last scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN) , or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider) .

Reference throughout this specification to “one embodiment” , “an embodiment” , or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment” , “in an embodiment” , and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including” , “comprising” , “having” , and variations thereof mean “including but are not limited to” , unless otherwise expressly specified. An enumerated listing of items does not imply that any or all of the items are mutually exclusive, otherwise unless expressly specified. The terms “a” , “an” , and “the” also refer to “one or more” unless otherwise expressly specified.

Furthermore, described features, structures, or characteristics of various embodiments may be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments. One skilled in the relevant art will recognize, however, that embodiments may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid any obscuring of aspects of an embodiment.

Aspects of different embodiments are described below with reference to schematic flowchart diagrams and/or schematic block diagrams of methods, apparatuses, systems, and program products according to embodiments. It will be understood that each block of the schematic flowchart diagrams and/or schematic block diagrams, and combinations of blocks in the schematic flowchart diagrams and/or schematic block diagrams, can be implemented by code. This code may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the schematic flowchart diagrams and/or schematic block diagrams for the block or blocks.

The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices, to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices, to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code executed on the computer or other programmable apparatus provides processes for implementing the functions specified in the flowchart and/or block diagram block or blocks.

The schematic flowchart diagrams and/or schematic block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of apparatuses, systems, methods and program products according to various embodiments. In this regard, each block in the schematic flowchart diagrams and/or schematic block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions of the code for implementing the specified logical function (s) .

It should also be noted that in some alternative implementations, the functions noted in the block may occur out of the order noted in the Figures. For example, two blocks shown in succession may substantially be executed concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more blocks, or portions thereof, to the illustrated Figures.

Although various arrow types and line types may be employed in the flowchart and/or block diagrams, they are understood not to limit the scope of the corresponding embodiments. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the depicted embodiment. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted embodiment. It will also be noted that each block of the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and code.

The description of elements in each Figure may refer to elements of proceeding figures. Like numbers refer to like elements in all figures, including alternate embodiments of like elements.

For sidelink, Rx UE may be in the coverage of network (IC) or out of coverage of network (OOC) . On the other hand, Tx UE may work in mode 1 or mode 2. In mode 1, the base unit (e.g. gNB) schedules resource (s) for sidelink transmission. In mode 2, Tx UE autonomously selects resource (s) for sidelink transmission. Tx UE may also be in the coverage of network (IC) or out of coverage of network (OOC) . When Tx UE is out of coverage of network (OOC) , the Tx UE must work in mode 2. However, when Tx UE is in the coverage of network (IC) , it can work either in mode 1 or in mode 2. Different scenarios are listed in Table 1 (two Tx UEs and one Rx UE are considered) :

Table 1

In the first embodiment, the first scenario is considered, in which the Tx UE (s) are in mode 1 and the Rx UE is in the coverage of network (IC) . The Tx UE performs sidelink transmission to the Rx UE.

As shown in Figure 2, in step 210, the gNB configures or preconfigures one or more sidelink (SL) DRX duration configurations for Rx UE. The gNB sends said one or more SL DRX duration configurations for Rx UE to the Tx UE and the Rx UE by higher layer signaling (e.g. RRC) . Step 210 is not necessarily performed just before the Tx UE performs the sidelink transmission. Instead, step 210 can be performed any time before the sidelink transmission. The sidelink DRX duration configuration includes a time period of sidelink reception for the Rx UE. During the time period of sidelink reception, the Rx UE is ready to perform sidelink reception, i.e., to monitor SCI on PSCCH and decode its associated data transmission on PSSCH. In case of DRX, the time period of sidelink reception may refer to ‘drx-ActiveTime’ . In particular, the time period of sidelink reception may include the desired starting time and the desired length of the time period. The time period of sidelink reception may be defined as a set of sidelink resources or a set of resource pools or a part of a resource pool in time domain. A resource pool is a set of resources preconfigured for sidelink reception. In other words, the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) can be examples corresponding to the set of sidelink resources (or the set of resource pools or a part of the resource pool) .

For example, the gNB may configure or preconfigure 8 SL DRX duration configurations for Rx UE as shown in Table 2. The SL DRX duration configuration may be configured or preconfigured based on cast type. Some SL DRX duration configurations may be used for a certain cast type (e.g. unicast, groupcast or broadcast) . In addition or alternatively, the SL DRX duration configuration may be configured or preconfigured based on traffic period and/or based on destination UE of traffic transmission and/or based on resource pool.

000	#0 SL DRX duration configuration
001	#1 SL DRX duration configuration
010	#2 SL DRX duration configuration
011	#3 SL DRX duration configuration

100	#4 SL DRX duration configuration
101	#5 SL DRX duration configuration
110	#6 SL DRX duration configuration
111	#7 SL DRX duration configuration

Table 2

In step 220, the Tx UE reports its sidelink assistance information of sidelink transmission to the gNB. The sidelink assistance information is an indication of the sidelink transmission from the Tx UE to the Rx UE. The sidelink assistance information may include traffic period, traffic size, destination UE (i.e. Rx UE) of the sidelink transmission, and/or cast type (unicast, groupcast or broadcast) of the sidelink transmission. The sidelink assistance information can be used for selecting a SL DRX duration configuration to be activated.

In step 230, the gNB sends a first downlink control information for scheduling sidelink transmission to the Tx UE. The first downlink control information includes at least the time period in which the sidelink transmission is scheduled to be sent from the Tx UE to the Rx UE.

In step 240, the gNB sends a second downlink control information to the Rx UE to activate a SL DRX duration configuration for sidelink reception.

There are several ways for implementing the second downlink control information.

In a first way, when the gNB configures (or preconfigures) and sends one SL DRX duration configuration in step 210, the second downlink control information activates the one SL DRX duration configuration for sidelink reception. That is, when the SL DRX duration configuration is activated, the Rx UE will monitor SCI on PSCCH based on the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) included in the activated SL DRX duration configuration. The second downlink control information may include a field (e.g. 1 bit) to represent that the second downlink control information is used to activate or deactivate the (pre-) configured SL DRX duration configuration. For example, the value of ‘1’ indicates to activate while the value of ‘0’ indicates to deactivate, or vice versa. Alternatively, the second downlink control information may be scrambled by a RNTI. The RNTI represents that the second downlink control information is used to activate the configured (or preconfigured) SL DRX duration configuration. Incidentally, the RNTI may also represent that the second downlink control information is used to deactivate the (pre-) configured SL DRX duration configuration.

In a second way, when the gNB configures (or preconfigures) and sends multiple SL DRX duration configurations for Rx UE in step 210, the gNB sends a second downlink control information to the Rx UE to activate one of the multiple SL DRX duration configurations. For example, the gNB may configure (or preconfigure) 8 SL DRX duration configurations for Rx UE as shown in the above Table 2. So, the second downlink control information may include a field (e.g. 3 bits) to represent that the second downlink control information is used to activate a SL DRX duration configuration from the multiple SL DRX duration configurations. The field with value ‘101’ may represent to activate #5 SL DRX duration configuration. Further, the second downlink control information can be scrambled by a RNTI. The RNTI represents the downlink control information is used to activate or deactivate SL DRX duration configuration. The Rx UE will monitor SCI on PSCCH based on the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) included in the activated SL DRX duration configuration.

In a third way, when the gNB configures (or preconfigures) and sends multiple SL DRX duration configurations for Rx UE in step 210, the gNB sends a second downlink control information to the Rx UE to activate one of the multiple SL DRX duration configurations, similar to the second way. Different from the second way, according to the third way, the second downlink control information includes at least two fields: a first field (e.g. 1 bit) represents that the second downlink control information is used to activate or deactivate a SL DRX duration configuration. For example, ‘1’ represents to activate a SL DRX duration configuration, and ‘0’ represents to deactivate a SL DRX duration configuration, or vice versa. A second field (e.g. 3 bits) represents that the second downlink control information is used to indicate which SL DRX duration configuration of the multiple SL DRX duration configurations is to be activated or deactivated. For example, the gNB may configure (or preconfigure) 8 SL DRX duration configurations for Rx UE as shown in the above Table 2. The value ‘010’ may represent to activate #2 SL DRX duration configuration. The Rx UE will monitor SCI on PSCCH based on the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) included in the activated SL DRX duration configuration.

In step 250, the Tx UE sends the sidelink transmission to the Rx UE based on the first downlink control information received from the gNB in step 230; and the Rx UE, based on the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) included in the activated SL DRX duration configuration, monitors SCI on PSCCH and decodes its associated data transmission on PSSCH so that the sidelink transmission sent from the Tx UE can be successfully received.

According to the first embodiment, when both Tx UE A and Tx UE B report their sidelink assistance informations to the gNB for indicating the sidelink transmissions to the same Rx UE, the gNB may send the second downlink control information to the Rx UE to activate the same SL DRX duration configuration, so that the Rx UE monitors SCI on PSCCH and decodes its associated data transmission on PSSCH in the same time period of sidelink reception for the sidelink transmissions from Tx UE A and Tx UE B. Incidentally, the first downlink control information is sent to the Tx UE A and Tx UE B, so that both Tx UE A and Tx UE B use the same time period for sidelink transmissions to the Rx UE. The SL DRX duration configuration to be activated can be selected in the following manner, with reference to the sidelink assistance information received from multiple Tx UEs. For example, when a reception ON duration of 20ms of a first SL DRX duration configuration is selected according to the sidelink assistance information received from Tx UE A while a reception ON duration of 30ms of a second SL DRX duration configuration is to be selected according to the sidelink assistance information received from Tx UE B, the activated SL DRX duration configuration may be selected according to a larger ON duration (i.e. 30ms) of the first and the second SL DRX duration configurations, i.e. the second SL DRX duration configuration will be selected as the activated SL DRX duration configuration. The activated SL DRX duration configuration may be additionally or alternatively selected according to comparison of priorities of multiple sidelink transmissions (e.g. indicated by Tx UE A and Tx UE B) . For example, when the sidelink transmission from Tx UE A has a higher priority than the sidelink transmission from Tx UE B, the activated SL DRX duration configuration may be selected according to the reception ON duration being consistent with the traffic period of the sidelink transmission from the Tx UE A. The activated SL DRX duration configuration may be additionally or alternatively selected based on the comparison of cast types (e.g. broadcast > groupcast > unicast) of multiple sidelink transmissions (e.g. indicated by Tx UE A and Tx UE B) . For example, when Tx UE A indicates a sidelink transmission of broadcast while Tx UE B indicates a sidelink transmission of groupcast, the activated SL DRX duration configuration may be selected according to the reception ON duration being consistent with the traffic period of the sidelink transmission from the Tx UE A.

According to a second embodiment, in scenario 2, when the Rx UE is out of coverage of network (OOC) , the Rx UE cannot receive the second downlink control information from the gNB in step 240.

In step 210, the gNB has preconfigured one or more SL DRX duration configurations for Rx UE and sent the same to the Tx UE and the Rx UE. Therefore, instead of receiving an activation signaling (e.g. the second downlink control information) from the gNB in step 240, the Rx UE according to the second embodiment receives the activation signaling (e.g. sidelink (SL) control information) from the Tx UE.

Figure 3 illustrates a method of transmitting sidelink (SL) control information from Tx UE.

In an optional step 310, the Rx UE sends a set of candidate SL DRX duration configurations, to the Tx UE. The Tx UE will activate one of the received SL DRX duration configurations. If step 310, which is optional, is not performed, the Tx UE will activate one of the SL DRX duration configurations for the Rx UE received in step 210.

In step 320, the Tx UE sends SL control information to the Rx UE. The SL control information activates one of the received SL DRX duration configurations in step 310 or in step 210. The activated SL DRX duration configuration can be selected from the multiple SL DRX duration configurations according to different criteria. If only one SL DRX duration configuration is received by the Tx UE, the received SL DRX duration configuration is selected. If multiple SL DRX duration configurations are received by the Tx UE, the activated SL DRX duration configuration can be selected in a similar manner as those for selecting the activated SL DRX duration configuration by the gNB, e.g. based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities of multiple sidelink transmissions, or based on the comparison of the cast types of multiple sidelink transmissions (e.g. broadcast > groupcast > unicast) .

In addition, the SL control information may include a field (e.g. of 1 bit) to indicate whether data transmission exists. For example, if the value of the field is ‘1’ , it means that data transmission to the Rx UE exists and the information on the activated SL DRX duration configuration is carried in the data transmission. The Rx UE should decode the data transmission for the activated SL DRX duration configuration. If the value of the field is ‘0’ , it means that the data transmission to the Rx UE does not exist, and the Rx UE would skip decoding the data transmission. When the data transmission to the Rx UE does not exist, the configurations of the time period of sidelink reception may be preconfigured (i.e. well known by the Tx UE and the Rx UE) , and the SL control information would contains an activation signaling for activating one of the preconfigured configurations of the time period of sidelink reception.

In step 330, the Rx UE monitors the SL transmissions in time period of sidelink reception included in the activated SL DRX duration configuration.

The method 300 applies to e.g. scenarios 1, 2 and 3, in which at least a Tx UE is in the coverage of network (IC) .

According to a third embodiment, if the Rx UE receives multiple (different) activations of the SL DRX duration configurations from multiple Tx UEs while each activated configuration is associated with a traffic (sidelink tranmsission) with different priorities, the Rx UE may choose one of the received activated SL DRX duration configurations, e.g. based on a larger ON duration among the multiple activated configurations, or based on the comparison of different priorities of the multiple activated configurations, or based on the comparison of the cast type (e.g. broadcast > groupcast > unicast) of the multiple activated configurations. The Rx UE may further send the selected SL DRX duration configuration to the Tx UEs, e.g. by transmitting a sidelink (SL) control information to the Tx UE.

Figure 4 illustrates a method of transmitting sidelink (SL) control information from Rx UE.

In step 410, the SL control information is sent from the Rx UE to the Tx UE as a sidelink transmission. The sidelink transmission may include only control information (in SCI) (i.e. no data transmission) or include both control information (in SCI) and data transmission. In both situations, the SL control information includes a field to indicate a time offset between the transmission of the SL control information and the active time of the selected SL DRX duration configuration (the selected time period of sidelink reception) . When the sidelink transmission includes data transmission, the configuration of the time period of sidelink reception (e.g., reception ON duration or DRX ON duration) is transmitted in the data transmission. When the sidelink transmission does not include data transmission, the configurations of the time period of sidelink reception may be preconfigured (i.e. well known by the Tx UE and the Rx UE) , and the control information would contains an activation signaling for activating one of the preconfigured configurations of the time period of sidelink reception.

In step 420, the Tx UE sends the sidelink transmission (including both SCI and data) in the time period of sidelink reception (e.g. reception ON duration or DRX ON duration) of the selected SL DRX duration configuration based on the SL control information received in step 410.

As mentioned above, the Tx UE may work in mode 1 or mode 2. In mode 1, the gNB schedules resource (s) for Tx UE transmitting SL DRX duration configuration (s) on sidelink. In this condition, the Tx UE is necessary to obtain a sidelink (SL) grant from the gNB for transmitting SL DRX duration configuration (s) . To achieve this, the Tx UE can send a dedicated scheduling request (SR) to the gNB to request a SL grant for Tx UE transmitting SL DRX duration configuration (s) . After the Tx UE receives the SL grant from the gNB, the Tx UE can perform step 320.

In addition, in step 310 and step 410, the sidelink transmission is performed by the Rx UE. In these steps, as the Rx UE performs the sidelink transmission (s) , it actually functions as a Tx UE. Therefore, before performing these steps, if the Rx UE (functioning as Tx UE) works in mode 1, the Rx UE is also necessary to obtain a SL grant from the gNB for transmitting SL DRX duration configuration (s) . To achieve this, the Rx UE (functioning as Tx UE) can send a dedicated scheduling request (SR) to the gNB to request a SL grant. After the Rx UE (functioning as Tx UE) receives the SL grant from the gNB, the Rx UE (functioning as Tx UE) can perform step 310 or step 410.

Figure 5 is a schematic flow chart diagram illustrating an embodiment of a method 500 for sidelink reception alignment. In some embodiments, the method 500 is performed by an apparatus, such as a base unit. In certain embodiments, the method 500 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 500 may include 510 transmitting, to a receiving remote unit and/or a transmitting remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving unit; and 520 in response to receiving an indication of the sidelink transmission, transmitting, to the receiving remote unit, a downlink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations. The step 510 may correspond to step 210 in Figure 2; and the step 520 may correspond to step 220 and step 240 in Figure 2.

Figure 6 is a schematic flow chart diagram illustrating an embodiment of a method 600 for sidelink reception alignment. In some embodiments, the method 600 is performed by an apparatus, such as a receiving remote unit (UE) . In certain embodiments, the method 600 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 600 may include 610 receiving, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit; and 620 receiving a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit. The step 610 may correspond to step 210 in Figure 2; and the step 620 may correspond to step 240 in Figure 2 or step 320 in Figure 3.

Figure 7 is a schematic flow chart diagram illustrating an embodiment of a method 700 for sidelink reception alignment. In some embodiments, the method 600 is performed by an apparatus, such as a transmitting remote unit (UE) . In certain embodiments, the method 700 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

The method 700 may include 710 receiving, from a base unit and/or a receiving remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to the receiving remote unit; and 720 transmitting, to the receiving remote unit, a sidelink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations. The step 710 may correspond to step 210 in Figure 2 or step 310 in Figure 3; and the step 720 may correspond to step 320 in Figure 3.

Referring to Figure 8, the UE (i.e. the remote unit) includes a processor, a memory, and a transceiver. The processor implements a function, a process, and/or a method which are proposed in Figures 6 and 7. The gNB (i.e. base unit) includes a processor, a memory, and a transceiver. The processors implement a function, a process, and/or a method which are proposed in Figure 5. Layers of a radio interface protocol may be implemented by the processors. The memories are connected with the processors to store various pieces of information for driving the processors. The transceivers are connected with the processors to transmit and/or receive a radio signal. Needless to say, the transceiver may be implemented as a transmitter to transmit the radio signal and a receiver to receive the radio signal.

The memories may be positioned inside or outside the processors and connected with the processors by various well-known means.

In the embodiments described above, the components and the features of the embodiments are combined in a predetermined form. Each component or feature should be considered as an option unless otherwise expressly stated. Each component or feature may be implemented not to be associated with other components or features. Further, the embodiment may be configured by associating some components and/or features. The order of the operations described in the embodiments may be changed. Some components or features of any embodiment may be included in another embodiment or replaced with the component and the feature corresponding to another embodiment. It is apparent that the claims that are not expressly cited in the claims are combined to form an embodiment or be included in a new claim.

The embodiments may be implemented by hardware, firmware, software, or combinations thereof. In the case of implementation by hardware, according to hardware implementation, the exemplary embodiment described herein may be implemented by using one or more application-specific integrated circuits (ASICs) , digital signal processors (DSPs) , digital signal processing devices (DSPDs) , programmable logic devices (PLDs) , field programmable gate arrays (FPGAs) , processors, controllers, micro-controllers, microprocessors, and the like.

Embodiments may be practiced in other specific forms. The described embodiments are to be considered in all respects to be only illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

A method, comprising:

transmitting, to a receiving remote unit and/or a transmitting remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving unit; and

in response to receiving an indication of the sidelink transmission, transmitting, to the receiving remote unit, a downlink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.
The method of claim 1, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The method of claim 1, wherein, the downlink control information includes a field to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The method of claim 1, wherein, the downlink control information is scrambled by a RNTI to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The method of claim 1, wherein, the downlink control information includes a field to indicate which sidelink reception duration configuration is activated or deactivated.
A method, comprising:

receiving, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit; and

receiving a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit.
The method of claim 6, further comprising: monitoring the sidelink transmission according to the activated sidelink reception duration configuration.
The method of claim 6, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The method of claim 6, wherein, the downlink control information includes a field to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The method of claim 6, wherein, the downlink control information is scrambled by a RNTI to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The method of claim 6, wherein, the downlink control information includes a field to indicate which sidelink reception duration configuration is activated or deactivated.
The method of claim 6, wherein, the sidelink control information includes a field to indicate that the activated sidelink reception duration configuration is contained in data transmission.
The method of claim 6, further comprising: sending a set of candidate sidelink reception duration configurations to the transmitting remote unit.
The method of claim 13, further comprising: sending a scheduling request for transmitting sidelink reception duration configuration (s) to the base unit; and in response to receiving a grant from the base unit, sending the set of candidate sidelink reception duration configurations to the transmitting remote unit.
The method of claim 6, wherein, when a plurality of sidelink reception duration configurations are activated, sending a selected activated sidelink reception duration configuration to the transmitting remote unit.
The method of claim 15, wherein, the activated sidelink reception duration configuration is selected based on a larger ON duration among multiple activated configurations, or based on the comparison of priorities among multiple activated configurations, or based on the comparison of cast types of multiple activated configurations.
A base unit, comprising:

a transmitter configured to transmit, to a receiving remote unit and/or a transmitting remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving unit; and

a receiver, wherein

in response to the receiver receiving an indication of the sidelink transmission, the transmitter is further configured to transmit, to the receiving remote unit, a downlink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.
The base unit of claim 17, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The base unit of claim 17, wherein, the downlink control information includes a field to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The base unit of claim 17, wherein, the downlink control information is scrambled by a RNTI to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The base unit of claim 17, wherein, the downlink control information includes a field to indicate which sidelink reception duration configuration is activated or deactivated.
A receiving remote unit, comprising:

a receiver configured to receive, from a base unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to a receiving remote unit, wherein,

the receiver is further configured to receive a control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations, wherein the control information is sidelink control information received from the transmitting remote unit or downlink control information received from the base unit.
The receiving remote unit of claim 22, further comprising a processor configured to monitor the sidelink transmission according to the activated sidelink reception duration configuration.
The receiving remote unit of claim 22, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The receiving remote unit of claim 22, wherein, the downlink control information includes a field to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The receiving remote unit of claim 22, wherein, the downlink control information is scrambled by a RNTI to represent that the downlink control information is used to activate or deactivate a sidelink reception duration configuration.
The receiving remote unit of claim 22, wherein, the downlink control information includes a field to indicate which sidelink reception duration configuration is activated or deactivated.
The receiving remote unit of claim 22, wherein, the sidelink control information includes a field to indicate that the activated sidelink reception duration configuration is contained in data transmission.
The receiving remote unit of claim 22, further comprising a transmitter configured to send a set of candidate sidelink reception duration configurations to the transmitting remote unit.
The receiving remote unit of claim 29, wherein, the transmitter is further configured to send a scheduling request for transmitting sidelink reception duration configuration (s) to the base unit; and in response to receiver receiving a grant from the base unit, the transmitter is further configured to send the set of candidate sidelink reception duration configurations to the transmitting remote unit.
The receiving remote unit of claim 22, further comprising a transmitter configured to, when a plurality of sidelink reception duration configurations are activated, send a selected activated sidelink reception duration configuration to the transmitting remote unit.
The receiving remote unit of claim 31, wherein, the activated sidelink reception duration configuration is selected based on a larger ON duration among multiple activated configurations, or based on the comparison of priorities among multiple activated configurations, or based on the comparison of cast types of multiple activated configurations.
A method, comprising:

receiving, from a base unit and/or a receiving remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from a transmitting remote unit to the receiving remote unit; and

transmitting, to the receiving remote unit, a sidelink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.
The method of claim 33, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The method of claim 33, further comprising: sending the sidelink transmission according to the activated sidelink reception duration configuration.
The method of claim 33, wherein, the sidelink control information includes a field to indicate that the activated sidelink reception duration configuration is contained in data transmission.
The method of claim 33, further comprising: sending a scheduling request for transmitting the sidelink control information to the receiving remote unit; and in response to receiving a grant from the base unit, sending the sidelink control information to the receiving remote unit.
The method of claim 33, further comprising: receiving a selected activated sidelink reception duration from the receiving remote unit; and sending the sidelink transmission according to the received selected activated sidelink reception duration configuration.
A transmitting remote unit, comprising:

a receiver configured to receive, from a base unit and/or a receiving remote unit, one or multiple sidelink reception duration configurations for a sidelink transmission to be sent from the transmitting remote unit to the receiving remote unit; and

a transmitter configured to transmit, to the receiving remote unit, a sidelink control information to activate the one sidelink reception duration configuration or one of the multiple sidelink reception duration configurations.
The transmitting remote unit of claim 39, wherein, the activated sidelink reception duration configuration is determined based on a larger ON duration among multiple configurations selected for multiple sidelink transmissions, or based on the comparison of priorities among multiple sidelink transmissions, or based on the comparison of cast types of multiple sidelink transmissions.
The transmitting remote unit of claim 39, wherein the transmitter is further configured to send the sidelink transmission according to the activated sidelink reception duration configuration.
The transmitting remote unit of claim 39, wherein, the sidelink control information includes a field to indicate that the activated sidelink reception duration configuration is contained in data transmission.
The transmitting remote unit of claim 39, wherein the transmitter is further configured to send a scheduling request for transmitting the sidelink control information to the receiving remote unit; and in response to the receiver receiving a grant from the base unit, send the sidelink control information to the receiving remote unit.
The transmitting remote unit of claim 39, wherein the receiver is further configured to receive a selected activated sidelink reception duration from the receiving remote unit; and the transmitter is further configured to send the sidelink transmission according to the received selected activated sidelink reception duration configuration.