WO2024007126A1

WO2024007126A1 - Methods for resource allocation of sl on unlicensed spectrum

Info

Publication number: WO2024007126A1
Application number: PCT/CN2022/103729
Authority: WO
Inventors: Junqiang CHENG; Tao Chen; Jing-Wei Chen
Original assignee: Mediatek Singapore Pte. Ltd.
Priority date: 2022-07-04
Filing date: 2022-07-04
Publication date: 2024-01-11
Also published as: CN117354951A

Abstract

This disclosure describes methods for resource allocation of SL transmitted on unlicensed spectrum. A new definition of sub-channel under CRB based, and IRB based transmission is proposed to be utilize as the resource allocation granularity of the frequency domain. The resource allocated for PSCCH can occupy (multiple) starting/leading sub-channel (s) and/or (multiple) fixed sub-channel (s) within (multiple) starting/leading RB set (s) / (LBT) channel (s) /LBT bandwidth (s) and/or (multiple) fixed RB set (s) / (LBT) channel (s) /LBT bandwidth (s) via RRC (pre-) configuration. The resource allocated for PSSCH can occupy (multiple) sub-channel (s) across (multiple) RB set (s) via SCI indication. The resource allocated for PSFCH can occupy (multiple) sub-channel (s) within one RB set via RRC (pre-) configuration and/or SCI indication under IRB based, and/or CRB based transmission according to the OCB requirement.

Description

METHODS FOR RESOURCE ALLOCATION OF SL ON UNLICENSED SPECTRUM

FIELD

The invention discussed below relates generally to wireless communication systems, and more particularly, to methods for resource allocation of SL operated on unlicensed spectrum.

BACKGROUND

Sidelink operated on unlicensed/shared spectrum (SL-U) is one of the most promising directions for SL evolution. However, considering the resource allocation frameworks in legacy NR unlicensed (NR-U) and SL are different, the design of resource allocation framework for SL-U will be a critical issue, and thus should be addressed as a fundamental premise to ensure that SL can be operated on unlicensed/shared spectrum.

SUMMARY

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

Various aspects of the present disclosure relate to methods of resource allocation for SL-U. SL-U UE can access single or multiple LBT channel (s) on which transmission (s) are performed. Both contiguous RB (CRB) based and interlace RB (IRB) based transmission can be supported for SL-U. One sub-channel with new definition can be used as the granularity of frequency domain resource allocation for SL-U. For IRB based transmission, one sub-channel can be defined as K (contiguous) interlace (s) . For CRB based transmission, one sub-channel can be defined as N contiguous RB (s) . For the indication of the sub-channel under CRB based and/or IRB based transmission, a bitmap and/or SLIV and be used. The sub-channel under both IRB and CRB can be defined within one RB set/ (LBT) channel/LBT bandwidth or across multiple RB sets/ (LBT) channels/LBT bandwidths if channel access procedures for transmission (s) on multiple (LBT) channels are supported. The definition of sub-channel in IRB based and CRB based transmission can be (pre-) configured and/or indicated via SIB and/or RRC and/or MAC-CE according to, such as the bandwidth, the numerology, and the COB requirements, etc.

In another aspect of the disclosure, the resource allocated for PSCCH can occupy (multiple) starting/leading sub-channel (s) and/or (multiple) fixed sub-channel (s) within (multiple) starting/leading RB set(s) / (LBT) channel (s) /LBT bandwidth (s) and/or (multiple) fixed RB set (s) / (LBT) channel (s) /LBT bandwidth (s) . The resource allocation information for PSCCH can be (pre-) configured and/or indicated via SIB and/or RRC and/or MAC-CE. Additionally, the resource allocated for PSSCH can occupy (multiple) sub-channel (s) within one RB set/ (LBT) channel/LBT bandwidth or across multiple RB sets/ (LBT) channels/LBT bandwidths if channel access procedures for transmission (s) on multiple (LBT) channels are supported. The resource allocation information for PSSCH can be (dynamically) indicated via SCI and/or MAC-CE. Besides, the resource allocated for PSFCH can occupy (multiple) sub-channel (s) within one RB set/ (LBT) channel/LBT bandwidth via SIB and/or RRC, and/or MAC-CE, and/or SCI as (pre-) configuration/indication under the IRB based transmission and/or CRB based transmission with the consideration of OCB requirements.

For the indication of the allocated resource configuration, the bitmap and/or SLIV can be used to indicate the information of the allocated resource. For example, a sub-channel indicator can be (pre-) configured to include the information of the allocated sub-channel. For example, the number of allocated sub-channel (s) , and/or the length of one allocated sub-channel. The RB set indicator can be (pre-) configured to include the information of allocated RB set (s) . For example, the start position of the first allocated RB set, and/or the length of (contiguous) allocated RB set (s) . The resource allocation indicator in SCI can be multiplexed with the existing resource allocation filed in legacy SCI. Alternatively, to differentiate with the existing SCI format, the new SCI format and/or SCI format indicator can be introduced.

After a successful LBT, the COT initiator can share the COT to the other UE (s) . The COT sharing UE (s) can be (pre-) configured to transmit packet with or without PSCCH. For the (potential) PSCCH from each COT sharing UE, the COT initiator will monitor the PSCCH at (multiple) (pre-) configured starting/leading sub-channel (s) and/or (multiple) (pre-) configured fixed sub-channel (s) within (multiple) (pre-) configured starting/leading RB set (s) and/or (multiple) (pre-) configured fixed RB set (s) within the corresponding allocated resources for each COT sharing UE.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed figures set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary diagram of the present resource allocation framework for SL-U including CRB based, and IRB based transmission.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

This invention is motived by, but not limited to, a scenario where the sidelink is transmitted on unlicensed/shared spectrum. Considering legacy NR-U and SL have individual resource allocation frameworks, for SL-U transmission scenario, one fundamental premise would be the design of the resource allocation framework and method. Therefore, in this disclosure, resource allocation methods for SL-U are proposed.

In this disclosure, SL-U UE can access a single channel on which transmission (s) are performed. Alternatively, the wideband operation can also be supported, which means that SL-U UE can access multiple channels on which transmission (s) are performed. Both CRB based and IRB based transmission can be supported for SL-U UE. One sub-channel with new definitions for CRB based and IRB based transmissions can be used as the resource allocation granularity of frequency domain via (pre-) configuration and/or indication of SIB and/or RRC and/or MAC-CE and/or SCI.

For CRB based transmission, one sub-channel can be defined as N contiguous RB (s) within one RB set/ (LBT) channel/LBT bandwidth. The value of N can be (pre-) configured and/or indicated by SIB and/or RRC and/or MAC-CE. For example, N can be defined as a value (s) chosen from the set or a sub-set of {1, 2, 3, …, 109, 110} under different configurations, such as the numerology, and/or the OCB requirement, and/or the multiplexing mode, and/or the COT information, and/or the scheduling information, and/or the configuration of the RBs within the intra-cell guard band if wideband operation is supported, etc. For IRB based transmission, one sub-channel can be defined as K (contiguous) interlace (s) within one RB set/ (LBT) channel/LBT bandwidth. The value of K can be (pre-) configured and/or indicated by SIB and/or RRC and/or MAC-CE. For example, K can be defined as a value (s) chosen from the set or a sub-set of {1, 2, 3, …, 9, 10} under different configurations, such as the numerology. For CRB based transmission, the number of RBs for different sub-channels can be (pre-) configured the same or different. For IRB based transmission, the number of RBs within different interlaces and/or sub-channels can be (pre-) configured the same or different. The relation between sub-channel (s) and interlace (s) and/or RB (s) can be indicated through a bitmap and/or SLIV.

Alternatively, if channel access procedures for transmission (s) on multiple (LBT) channels are supported, the sub-channel can be defined within one RB set/ (LBT) channel/LBT bandwidth as describe above, and/or across multiple RB sets/ (LBT) channels/LBT bandwidths for both CRB based and IRB based transmission. For the case that the sub-channel is defined across multiple RB sets/ (LBT) channels/LBT bandwidths, besides the information of the sub-channel defined within one RB set/ (LBT) channel/LBT bandwidth, the additional information about the RB sets/ (LBT) channels/LBT bandwidths that the sub-channel is defined in on should also be (pre-) configured and/or indicated. Besides, for wideband operation, an intra-cell guard band between two consecutive RB sets/ (LBT) channels/LBT bandwidths can be (pre-) configured, and the RBs within the intra-cell guard band can be configured to belong to the resource pool. In this case, the sub-channel can also be (pre-) configured to include the RBs within the intra-cell guard band.

As an example described in Figure 1, the channel access procedures are operated on a wide channel bandwidth comprised of two (LBT) channels/LBT bandwidths/RB sets. In this example, the channel bandwidth is 40 MHz. As illustrated in Figure 1, the channel bandwidth can be divided into two parts. One is the inter-cell guard band located at the two end parts of the channel bandwidth. Another one is the transmission bandwidth can be used for SL-U transmission. In this example, the transmission bandwidth is comprised of 106 RBs, where the middle 6 RBs are (pre-) configured as the intra-cell guard band and the other RBs within the transmission bandwidth are divided into two RB sets each with 50 RBs. Before the SL-U UE can transmit traffic on the channel bandwidth, it should perform the multiple channel access procedures on the channel bandwidth. If the multiple channel access procedures are judged as successful, the SL-U UE can start the CRB based transmission or IRB based transmission as (pre-) configured.

For the case of CRB based transmission, as shown in Figure 1, an example is that one sub-channel can be defined as N consecutive RBs within one RB set. According to the (pre-) configuration, if the RBs within the intra-cell guard band belong to the resource pool, the value of N can be (pre-) configured from the set of {1, 2, …, 55, 56} . Otherwise, if the RBs within the intra-cell guard band does not belong to the resource pool, the value of N can be (pre-) configured from {1, 2, …, 49, 50} . For the case of IRB based transmission, an example is that one sub-channel can be defined as K (contiguous) interlace (s) within one RB set. As for the example shown in Figure 1, the value of K can be (pre-) configured from the set or a sub-set of {1, 2, …, 4, 5} . According to the (pre-) configuration, if the interlaces (RBs) within the intra-cell guard band belong to the resource pool, the sub-channel can occupy the interlaces (RBs) within the intra-cell guard band. Otherwise, the sub-channel cannot occupy the interlaces (RBs) within the intra-cell guard band.

For the cases that the channel access and transmission are operated on a single and/or multiple (LBT) channel (s) (i.e., wideband operation) , the resources allocated for PSCCH can be configured to occupy (multiple) starting/leading sub-channel (s) and/or (multiple) fixed sub-channel (s) within (multiple) starting/leading RB set (s) / (LBT) channel (s) /LBT bandwidth (s) and/or (multiple) fixed RB set (s) / (LBT) channel (s) /LBT bandwidth (s) . The resource allocation configuration can be (pre-) configured and/or indicated via SIB and/or RRC and/or MAC-CE. The resources allocated for PSSCH can be configured to occupy (multiple) sub-channel (s) within one RB set or across multiple RB sets. The resources allocated for PSFCH can be (pre-) configured and/or indicated to occupy (multiple) sub-channel (s) within one RB set via SIB and/or RRC and/or SCI under the IRB based transmission and/or CRB based transmission with the consideration of the OCB requirements.

The resource allocation configuration can be indicated via SCI. Besides, the resource can be indicated through the bitmap and/or SLIV configuration. For example, for the case that the sub-channel is defined within one RB set. The SCI can be (pre-) configured to include the sub-channel indicator, and/or RB set indicator. The sub-channel indicator can be (pre-) configured to include the information of the allocated sub-channel (s) , such as the number of allocated sub-channel (s) , and/or the length of one allocated sub-channel if the transmission is CRB based. The RB set indicator can be (pre-) configured to include the information of the allocated RB set (s) , such as the start position of the first allocated RB set, and/or the length/number of the allocated RB set (s) . For another example, in the case that the sub-channel is defined across multiple RB sets, the SCI can be (pre-) configured to include the sub-channel indicator, including the number of allocated sub-channel (s) , and/or the length of one allocated sub-channel if the transmission is CRB based. The resource allocation indicator can be multiplexed with the existing resource allocation filed in legacy SCI. Alternatively, to differentiate with the existing SCI format, the new SCI format and/or SCI format indicator can be introduced.

The COT initiator can be (pre-) configured to occupy (a sub-set of) (multiple) RB set (s) in the leading/beginning position of the COT. Besides, the COT can be used by the COT initiator and/or shared by the COT initiator to the other SL-U UEs in TDM and/or FDM modes as (pre-) configured. For the case that the OCB requirements need be satisfied, if TDM mode is adopted, IRB based transmission can be configured as a default way and CRB can only be used if it can satisfy the OCB requirements. If FDM mode is adopted, both IRB based and CRB based transmission can be used as (pre-) configured. For the case that the OCB requirements do not need to be satisfied, both IRB based and CRB based transmission can be used for both TDM and FDM modes as (pre-) configured.

After a successful LBT, the COT initiator can share the COT to the other UE (s) . The COT sharing UE (s) can be (pre-) configured to transmit packet with or without PSCCH. For the (potential) PSCCH from each COT sharing UE, the COT initiator will monitor the PSCCH at (multiple) (pre-) configured starting/leading sub-channel (s) and/or (multiple) (pre-) configured fixed sub-channel (s) within (multiple) (pre-) configured starting/leading RB set (s) and/or (multiple) (pre-) configured fixed RB set (s) within the corresponding allocated resource for each COT sharing UE.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “UE, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ”

While aspects of the present disclosure have been described in conjunction with the specific embodiments thereof that are proposed as examples, alternatives, modifications, and variations to the examples may be made. Accordingly, embodiments as set forth herein are intended to be illustrative and not limiting. There are changes that may be made without departing from the scope of the claims set forth below.

Claims

A method of wireless communication, comprising:

the resource allocation framework for SL transmission on unlicensed spectrum.
The method of claim 1, wherein the transmission can be CRB based and/or IRB based as (pre-) configured via SIB and/or RRC and/or MAC-CE.
The method of claim 1, wherein the resource allocation granularity in frequency domain can be (pre-) configured as sub-channel with a new definition.
The method of claim 3, wherein the sub-channel can be defined as (contiguous) RB (s) and (contiguous) ) interlace (s) for CRB based transmission and IRB based transmission, respectively, via SIB and/or RRC and/or MAC-CE (pre-) configuration.
The method of claim 3, wherein the sub-channel can be indicated a bitmap and/or SLIV.
The method of claim 1, wherein the resource allocated for PSCCH can occupy (multiple) starting/leading sub-channel (s) and/or (multiple) fixed sub-channel (s) within (multiple) starting/leading RB set (s) / (LBT) channel (s) /LBT bandwidth (s) and/or (multiple) fixed RB set (s) / (LBT) channel (s) /LBT bandwidth (s) via SIB and/or RRC and/or MAC-CE (pre-) configuration.
The method of claim 1, wherein the resource allocated for PSSCH can occupy (multiple) sub-channel (s) within one RB set or across multiple RB sets via SCI indication.
The method of claim 1, wherein the resource allocated for PSFCH can occupy (multiple) sub-channel (s) within one RB set via SIB and/or RRC (pre-) configuration and/or SCI indication under IRB based, and/or CRB based transmission with the consideration of the OCB requirements.
The method of claim 1, wherein the resource can be indicated through the bitmap and/or SLIV.