WO2020062043A1

WO2020062043A1 - Ue capability dependent sync priority determination mechanism for v2x communication

Info

Publication number: WO2020062043A1
Application number: PCT/CN2018/108377
Authority: WO
Inventors: Feifei Zhang; Tao Chen
Original assignee: Mediatek Singapore Pte. Ltd.
Priority date: 2018-09-28
Filing date: 2018-09-28
Publication date: 2020-04-02

Abstract

This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus for sync priority determination for V2X communication depending on UE capability. UE can determine which rule is applied depending on the UE capability, e. g., whether/how to using LTE eNB and/or LTE UE as the sync source for a NR V2X UE w/wo LTE/LTE-V2X capability.

Description

UE CAPABILITY DEPENDENT SYNC PRIORITY DETERMINATION MECHANISM FOR V2X COMMUNICATION

FIELD OF INVENTION

This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus for the synchronization sources selection and related priority rules for NR V2X UEs.

BACKGROUND OF THE INVENTION

In 5G new radio V2X sidelink communication, vehicles need to setup synchronization with either base stations, GNSS, or UEs to get timing alignment. However, there are plenty of devices that can provide synchronization, the priority rules are needed for a particular NR V2X UE to get synchronization.

SUMMARY OF THE INVENTION

For a NR V2X UE, the synchronization rules are based on the deployment of operator setting and the capability of UE to decoding synchronization signals.

For NR only and NR-V2X only UE, GNSS, gNB, and NR UE can be the sidelink synchronization sources, and the defined priority rules 1) R1-1a and R1-1b in Table 1, 2) R1-2a and R1-2b in Table 2 can be used for sidelink synchronization sources selection.

For the NR V2X UE that can support NR, LTE and NR V2X and services, GNSS, gNB, eNB and NR UE can be the synchronization sources. The defined priority rules 1) R2-1a , R2-1b and R2-1c in Table 3, 2) R2-2a, R2-2b and R2-2c in Table 4 can be used for sidelink synchronization sources selection.

For the NR V2X UE that can support NR, NR V2X and LTE V2X services, GNSS, gNB, NR UE and LTE UE can be the synchronization sources. The defined priority rules 1) R3-1a , R3-1b in Table 5, 2) R3-2a, R3-2b and R3-2c in Table 6 can be used for sidelink synchronization sources selection.

For the NR V2X UE that can support both NR and LTE, as well as NR V2X and LTE V2X services, GNSS, eNB, gNB, NR UE and LTE UE can be the synchronization sources. For a NR V2X UE, the synchronization rules are based on the deployment of operator setting and the capability of UE to decoding synchronization signals. The defined priority rules 1) R4-1a , R4-1b and R4-1c in Table 7, 2) R4-2a, R4-2b and R4-2c in Table 8 can be used for sidelink synchronization sources selection.

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 an exemplary block diagram of a user equipment (UE) according to an embodiment of the disclosure.

DETAILED DESCRIPTION

Table. 1

Table. 1 is the priority rules for cases the frequency for sidelink communication is configured from cells for NR only and NR V2X only UE.

Table. 2

Table. 2 shows priority rules for cases when the frequency for sidelink communication is preconfigured for NR only and NR V2X only UE.

Table. 3

Table. 3 shows priority rules for cases when the frequency for sidelink communication is configured from cells for NR/LTE and NR V2X only UE.

Table. 4

Table. 4 shows priority rules for cases when the frequency for sidelink communication is pre-configured for NR/LTE and NR V2X only UE.

Table. 5

Table. 5 is the priority rules for cases the frequency for sidelink communication is configured from cells for NR only and NR V2X/LTE V2X UE.

Table. 6

Table. 6 is the priority rules for cases the frequency for sidelink communication is pre-configured for NR only and NR V2X/LTE V2X UE.

Table. 7

Table. 7 shows priority rules for cases when the frequency for sidelink communication is configured from cells for UE support NR/LTE and NR V2X and LTE V2X.

Table. 8

Table. 8 shows priority rules for cases when the frequency for sidelink communication is configured from cells for UE support NR/LTE and NR V2X and LTE V2X.

In the Table 1 and Table 2, NR_UE _gNB and NR_UE _GNSS represents the NR_UE that use gNB and GNSS as synchronization sources, respectively. NR_UE _{NR_UE-gNB} represents NR UE that use NR_UE _gNB as sync source, and NR_UE _{NR_UE-GNSS} represents NR UE that use NR_UE _GNSS as sync source. NR_UE _other represents NR UEs that exclude the UEs in the higher prioty. In below discussions, similar formation for other tables can be inferred accordingly. The typeTxSync in Table 1 and syncPriority in Table 2 are signaled from UE-specific RRC/SIB and pre-configuration, respectively.

For the cases that the frequency for sidelink communication is configured from cells, the priority rules in Table 1 can be applied for the UEs that only support NR and NR V2X services. For the cases that the frequency for sidelink communication is from pre-configuration, e.g., from UICC, the priority rules in Table 2 can be applied for the UEs that only support NR and NR V2X services.

For the NR V2X UE that can support both NR and LTE, as well as NR V2X and LTE V2X services, GNSS, eNB, gNB, NR UE and LTE UE can be the synchronization sources. For a NR V2X UE, the synchronization rules are based on the deployment of operator setting and the capability of UE to decode synchronization signals.

The operator can set the priority to be eNB, gNB or GNSS depend on the deployment of cellular system, e.g., if it is set to gNB, the UEs with gNB as synchronization sources and UEs that synchronized to these UEs can be the synchronization sources, and UEs directly synchronized to gNB have higher priority than those indirectly synchronized to gNB.

It depends on whether the UE is able to decode LTE, NR, LTE V2X or NR V2X synchronization signals in the synchronization sources selection. The defined priority rules 1) R2-1a , R2-1b and R2-1c in Table 3, 2) R2-2a, R2-2b and R2-2c in Table 4 , 3) R3-1a and R3-1b in Table 5, 4) R3-2a, R3-2b and R3-2c in Table 8 , 5) R4-1a , R4-1b and R4-1c in Table 7, 6) R4-2a, R4-2b and R4-2c in Table 8 can be used for sidelink synchronization sources selection. Related operator deployment and UE capability should be considered to preclude the synchronization sources that are unable or unusable to provide the synchronization.

In one embodiment, the frequency list can be provided with the NR (gNB) or LTE (eNB) deployment information so that UE can know which rule can be applied further considering UE’s capability on whether to support NR/LTE uu link and/or NR/LTE V2X sidelink. The detailed rule is defined as above.

Fig. 1 shows an exemplary block diagram of a UE 800 according to an embodiment of the disclosure. The UE 800 can be configured to implement various embodiments of the disclosure described herein. The UE 800 can include a processor 810, a memory 820, and a radio frequency (RF) module 830 that are coupled together as shown in Fig. 1. In different examples, the UE 800 can be a mobile phone, a tablet computer, a desktop computer, a vehicle carried device, and the like.

The processor 810 can be configured to perform various functions of the UE 120 described above. 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:

sync source prioritization and determination based on UE capability;

receiving a frequency list for V2X communication;

performing the search for sync source depending on V2X communication frequency, the corresponding gNB or eNB deployment in the frequency and the UE capability; and

performing prioritization and determination of the sync source based on the corresponding pre-defined rule.
The method of claim 1, wherein the frequency for V2X communication may be indicated with potential deployment of NR BS, LTE BS or none of them.
The method of claim 1, wherein the different prioritization rule is defined and selected depending on the UE capability and the frequency.