WO2022027592A1

WO2022027592A1 - Partial sensing enhancement for sl resource allocation

Info

Publication number: WO2022027592A1
Application number: PCT/CN2020/107818
Authority: WO
Inventors: Tao Chen; Ming-Yuan Cheng; Ahmet Umut UGURLU
Original assignee: Mediatek Singapore Pte. Ltd.
Priority date: 2020-08-07
Filing date: 2020-08-07
Publication date: 2022-02-10
Also published as: CN114071410A

Abstract

For SL resource allocation, the UE can perform partial sensing for resource allocation and transmission while saving the power. To keep the sensing performance while saving the power, UE can perform both the periodic sensing and one-shot sensing to detect the resource reservation from both the periodic transmission and aperiodic transmission. In addition, an indicator can be carried in SCI to indicate such UE is a partial sensing UE with the need of power saving. So that the other UE can transmit data to the partial sensing UE during the sensing duration (i.e., the periodic sensing duration and/or one-shot sensing duration). Or a common SL DRX pattern can be configured for such partial sensing UE.

Description

PARTIAL SENSING ENHANCEMENT FOR SL RESOURCE ALLOCATION

FIELD OF INVENTION

This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus about Partial Sensing Enhancement for SL Resource Allocation.

BACKGROUND OF THE INVENTION

In 5G new radio, V2X sidelink (SL) communication can be supported by the unicast, groupcast and broadcast communications. However, there are some issues to be addressed for power saving by partial sensing for resource allocation of the SL communication.

SUMMARY OF THE INVENTION

This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus about the partial sensing enhancement for SL resource allocation.

For SL resource allocation, the UE can perform partial sensing for resource allocation and transmission while saving the power. To keep the sensing performance while saving the power, UE can perform both the periodic sensing and one-shot sensing to detect the resource reservation from both the periodic transmission and aperiodic transmission. In addition, an indicator can be carried in SCI to indicate such UE is a partial sensing UE with the need of power saving. So that the other UE can transmit data to the partial sensing UE during the sensing duration (i.e., the periodic sensing duration and/or one-shot sensing duration) . Or a common SL DRX pattern can be configured for such partial sensing UE. If any Tx UE transmits the data to the partial sensing UEs, it can select the resources during SL DRX_On duration for transmission. If the SL unicast is established, the Tx UE can further follow the partial sensing UE’s sensing pattern for data reception based on PC5-RRC signaling exchange between UEs. So the partial sensing UEs may be active during the (common) SL DRX-On duration for broadcast/unicast reception (and sensing) , its own partial sensing duration (periodic and one-short sensing windows) for unicast reception and sensing, and/or its own transmission time. In addition, one-shot sensing can be done periodically supposing there is the periodic data transmission with one-shot sensing before each transmission. In this case, it can be considered as dual-period sensing for such periodic data transmission. Moreover, the one-shot sensing can be applied before the transmission of any reserved or (re-) selected resources. Additionally, the resource (re-) selection window may include the overlapping duration between the periodic sensing pattern and the time duration sensed during one-shot sensing to avoid the impact from the periodic and aperiodic transmissions by the others.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

Fig. 1 shows the procedure for the UE to perform the partial sensing for resource allocation.

Fig. 2 shows the procedure for Rx UE to transmit the assistance information.

Fig. 3 shows an exemplary block diagram of a UE (a.k.a device) according to an embodiment of the disclosure.

DETAILED DESCRIPTION

Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to ... " . Also, the term "couple" is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections. The making and using of the embodiments of the disclosure are discussed in detail below. It should be appreciated, however, that the embodiments can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative, and do not limit the scope of the disclosure. Some variations of the embodiments are described. Throughout the various views and illustrative embodiments, like reference numbers are used to designate like elements.

The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. Note that the 3GPP specifications described herein are used to teach the spirit of the invention, and the invention is not limited thereto.

For SL resource allocation, the UE can perform partial sensing for resource allocation and transmission while saving the power. To keep the sensing performance while saving the power, UE can perform both the periodic sensing and one-shot sensing to detect the resource reservation from both the periodic transmission and aperiodic transmission. To detect the periodic transmission, the periodic sensing pattern defined by the periodicity, sensing duration and/or the time offset is used. To detect the aperiodic transmission, the aperiodic (or one-shot) sensing is applied. Such one-shot sensing is occurred before the resource (re-) selection with N slots duration. Considering SCI can at most indicate the reserved resource 32 slots away from the current time, N can be set as 31 or 32 so that the aperiodic resource reservation can be sensed in the past 31 or 32 slots. In addition, one-shot sensing can be done periodically supposing there is the periodic data transmission with one-shot sensing before each transmission for resource (re-) selection. In this case, it can be considered as dual-period sensing for such periodic data transmission. Moreover, the one-shot sensing can be applied before the transmission or (re-) selection of any reserved or (re-) selected resources. Additionally, the resource (re-) selection window may include the overlapping duration between the periodic sensing pattern and the time duration potentially reserved during one-shot sensing to avoid the impact from both the periodic and aperiodic transmissions by the others. Such partial sensing is especially beneficial for the vulnerable users (VRU) to save the power.

Fig. 1 shows the procedure for the UE to perform the partial sensing for resource allocation. Supposing the UE with the periodic traffic for transmission every 1s, UE may perform periodic sensing every P1 slots/ms with the duration (D1) of m slots/ms (e.g., 10 slots/ms) so that any other periodic transmission with the periodicity multiple of P1 can be detected. Such P1/D1 pattern can be used for sensing of periodic reservation by other UEs. P1 can be derived from the reservation periodicities (pre-) configured per resource pool. The time offset of P1/D1 pattern can be derived from the packet arrival time known or resource (re-) selection time at Rx UE. Supposing the earliest available time for potential transmission or the time for the packet arrival or the time for resource (re-) selection is at R1, then it can be considered as the starting time of the D1. Accordingly, P1/D1 pattern can be determined. It implies the partial sensing results can be timely used for resource (re-) selection without any latency impact on the packet transmission. For example, D1 locations can be {t, t+m} with periodicity P1 wherein t is the packet arrival time or resource (re-) selection time. Additionally some processing time or minimum time offset can be added so that the D1 locations can be {t+mint, t+mint+m} with the periodicity P1.

As shown in Fig. 1, Additionally, UE may perform another another sensing (or one-shot sensing) every P2 slots/ms with the duration (D2) of m slots/ms (e.g., 31 slots/ms) considering the periodic traffic for transmission every 1s. In this case P2 can be set as 1s, i.e., same as the periodicity of the periodic transmission. Such sensing should be happened before the (re-) selection time determined by UE based on the packet arrival time and processing time. So any other aperiodic transmission falling into the selection window can be detected. P2/D2 pattern for sensing of aperiodic reservation or multiple resource reservation with up to 32 slots as indicated in SCI. It means that D2 can be (pre-) configured or specified up to 32 slots. The ending time of sensing should be before or at the (re-) selection of the resources. For example, it can be the time for resource (re-) selection (or the time for packet arrival) minus the processing time, i.e., t-T_proc. Accordingly the starting time for D2 sensing can be derived from the ending time and the D2 value, i.e., t-T_proc-32 supposing D2 = 32 slots.

UE (or VRU) should select resources for TB (re-) transmissions during the selection window which at least includes P1/D1 pattern, the duration with potential aperiodic transmission by sensing in D2 and/or the packet delay budget (PDB) . the duration with potential aperiodic transmission by sensing in D2 can be {t) , t+m) } supposing D2 sensing happens at {t-m, t) . If considering some processing time before and/or after t. the duration can be {t+MinT) , t+m-MinT) } or {t+MinT) , t+m-2*MinT) } or {t+MinT) , t+m-MinT-T_proc) } supposing D2 sensing happens at {t-D2-T_proc, t-T_proc} or {t-D2-MinT, t-MinT} . Ideally, the overlapping duration between P1/D1 pattern and the duration with potential aperiodic transmission by sensing in D2 should be prioritized for resource (re-) selection due to sufficient sensing information. Besides, the delay budget should be considered for resource (re-) selection so that the latency requirement for the packet can be satisfied.

Additionally, for re-selection of the resources due to re-evaluation or preemption, one short sensing will be still applied with the D2 location derived from the re-selection time or the time for the reserved resources. For example, as shown in Fig. 1, consider the pre-emption on R2 resource reserved in R1, the UE will perform D2 sensing with the ending time before or at the time instant with R2 time minus T3. Here, T3 can be the processing time as T_proc. Meanwhile, P1/D1 sensing is performed anyway. So the re-selection of the resource can be based on P1/D1 sensing, the updated D2 sensing and the packet delay budget.

An indicator can be carried in SCI to indicate such UE is a partial sensing UE with the need of power saving. So that the other UE can transmit data to the partial sensing UE during the sensing duration (i.e., the periodic sensing duration and/or one-shot sensing duration) . Or a common SL DRX pattern can be configured for such partial sensing UE. If any Tx UE transmits the data to the partial sensing UEs, it can select the resources during SL DRX_On duration for transmission. If the SL unicast is established, the Tx UE can further follow the partial sensing UE’s sensing pattern for data reception based on PC5-RRC signaling exchange between UEs. So the partial sensing UEs may be active during the (common) SL DRX-On duration for broadcast/unicast reception (and sensing) , its own partial sensing duration (periodic and one-short sensing windows) for unicast reception and sensing, and/or its own transmission time. For the other time, the partial sensing UE can go to sleep for saving power, except for the SL synchronization time if needed.

Additionally, the partial sensing UE can perform or assume sensing only on PSCCH-DMRS so that they can go to micro sleep for the rest of the time in the slot thanks to the front loaded PSCCH in the slot.

As shown in Fig. 2. The UE A can perform sensing and data reception during Rx time when the SL DRX patterns can be aligned or (full/partial) overlapping with partial sensing pattern. The other UE, e.g., UE B should transmit data in Rx duration of UE A. UE B can know such pattern based on (pre-) configuration per resource pool or PC5-RRC signaling or broadcast information. The indicator for partial sensing or VRU type UE in SCI of the UE A may help the other UE to derive/determine the Rx pattern associated with some (pre-) configuration.

Additionally, UE B can follow Tx pattern for the reception of UE A’s transmission, which also reduce the complexity and power consumption for UE B by avoidance of the full time detection on UE A’s transmission.

Fig. 3 shows an exemplary block diagram of a UE (a.k.a device) according to an embodiment of the disclosure. A processor 810 can be configured to perform various functions of the embodiments of the invention. The processor 810 can include signal processing circuitry to process received or to be transmitted data according to communication protocols specified in, for example, LTE and NR standards. Additionally, the processor 810 may execute program instructions, for example, stored in the memory 820, to perform functions related with different communication protocols. The processor 810 can be implemented with suitable hardware, software, or a combination thereof. For example, the processor 810 can be implemented with application specific integrated circuits (ASIC) , field programmable gate arrays (FPGA) , and the like, that includes circuitry. The circuitry can be configured to perform various functions of the processor 810.

In one example, the memory 820 can store program instructions that, when executed by the processor 810, cause the processor 810 to perform various functions as described herein. The memory 820 can include a read only memory (ROM) , a random access memory (RAM) , a flash memory, a solid state memory, a hard disk drive, and the like.

The RF module 830 can be configured to receive a digital signal from the processor 810 and accordingly transmit a signal to a base station in a wireless communication network via an antenna 840. In addition, the RF module 830 can be configured to receive a wireless signal from a base station and accordingly generate a digital signal which is provided to the processor 810. The RF module 830 can include digital to analog/analog to digital converters (DAC/ADC) , frequency down/up converters, filters, and amplifiers for reception and transmission operations. For example, the RF module 830 can include converter circuits, filter circuits, amplification circuits, and the like, for processing signals on different carriers or bandwidth parts.

The UE 800 can optionally include other components, such as input and output devices, additional CPU or signal processing circuitry, and the like. Accordingly, the UE 800 may be capable of performing other additional functions, such as executing application programs, and processing alternative communication protocols.

The processes and functions described herein can be implemented as a computer program which, when executed by one or more processors, can cause the one or more processors to perform the respective processes and functions. The computer program may be stored or distributed on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with, or as part of, other hardware. The computer program may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems. For example, the computer program can be obtained and loaded into an apparatus, including obtaining the computer program through physical medium or distributed system, including, for example, from a server connected to the Internet.

The computer program may be accessible from a computer-readable medium providing program instructions for use by or in connection with a computer or any instruction execution system. A computer readable medium may include any apparatus that stores, communicates, propagates, or transports the computer program for use by or in connection with an instruction execution system, apparatus, or device. The computer-readable medium can be magnetic, optical, electronic, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. The computer-readable medium may include a computer-readable non-transitory storage medium such as a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM) , a read-only memory (ROM) , a magnetic disk and an optical disk, and the like. The computer-readable non-transitory storage medium can include all types of computer readable medium, including magnetic storage medium, optical storage medium, flash medium and solid state storage medium.

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, comprising:

receiving the SL (pre-) configuration;

determining one or multiple sensing patterns;

performing sensing for resource (re-) selection;

(re-) selecting the resources based on the sensing results from one or multiple sensing patterns; and transmitting the message based on the (re-) selected resources.