Search

US-12628099-B2 - Terminal

US12628099B2US 12628099 B2US12628099 B2US 12628099B2US-12628099-B2

Abstract

A UE 200 acquires time information used in a system from a network. The UE 200 receives a message indicating that the time information is updated from the network, and acquires the time information according to the reception of the message.

Inventors

  • Tianyang Min

Assignees

  • NTT DOCOMO, INC.

Dates

Publication Date
20260512
Application Date
20210609
Priority Date
20200610

Claims (4)

  1. 1 . A terminal comprising: a receiver that receives a DLInformationTransfer message from a network; and a processor that acquires: time information included in the DLInformationTransfer message, in response to determining that the time information is present in the DLInformationTransfer message, wherein, after acquiring the time information from the DLInformationTransfer message, the processor stops acquiring the time information included in system information transmitted from the network; and the time information included in the system information in response to determining that the time information is not present in the DLInformationTransfer message.
  2. 2 . The terminal according to claim 1 , further comprising: a transmitter that transmits a transmission request for the time information to the network.
  3. 3 . A communication method of a terminal, the method comprising: a reception step of receiving a DLInformationTransfer message from a network; and a control step of acquiring: time information included in the DLInformationTransfer message, in response to determining that the time information is present in the DLInformationTransfer message, wherein, after acquiring the time information from the DLInformationTransfer message, stopping acquiring the time information included in system information transmitted from the network; and the time information included in the system information is acquired in response to determining that the time information is not present in the DLInformationTransfer message.
  4. 4 . A communication system including a base station and a terminal, wherein the base station comprises a transmitter that transmits time information used in a system, using a DLInformationTransfer message or system information, and the terminal comprises: a receiver that receives the DLInformationTransfer message from the base station; and a processor that acquires: the time information included in the DLInformationTransfer message, in response to determining that the time information is present in the DLInformationTransfer message, wherein after acquiring the time information from the DLInformationTransfer message, the processor stops acquiring the time information included in system information transmitted from the base station; and the time information included in the system information in response to determining that the time information is not present in the DLInformationTransfer message.

Description

TECHNICAL FIELD The present invention relates to a terminal for executing radio communication, particularly a terminal for acquiring time information in an NR (5G) system. BACKGROUND ART 3rd Generation Partnership Project (3GPP) specifies 5th generation mobile communication system (5G, also called New Radio (NR) or Next Generation (NG), further, a succeeding system called Beyond 5G, 5G Evolution or 6G is being specified. 3GPP Release-16 will see NR support for Industrial Internet of Things (IIoT) (see Non-Patent Literature 1). To enable support for IIoT, synchronizing a radio base station (gNB) with a terminal (User Equipment, UE) is listed as a work item (WI). Specifically, in order to realize high-precision synchronization between the gNB and the UE, it is proposed to include an information element (IE) called referenceTimeInfo-r16 in the System Information Block (SIB) 9 (see Non-Patent Literature 2). referenceTimeInfo-r16 (time information) indicates the NR (5G) Internalsystem clock (which may be referred to as time or timing). It is also proposed that the UE may request the time information from the gNB (network) by including referenceTimePreference-r16 in the UEAssistanceInformation. CITATION LIST Non-Patent Literature Non-Patent Literature 1 “Revised WID: Support of NR Industrial Internet of Things (IoT)”, RP-192324, 3GPP TSG RAN Meeting #85, 3GPP, September 2019Non-Patent Literature 2 “Correction of NR IIoT”, R2-2004955, 3GPP TSG-RAN WG2 Meeting #110 e, 3GPP, June 2020 SUMMARY OF INVENTION However, the operation related to synchronization between the gNB and the UE described in Non-Patent Literature 2 may have the following problems. Specifically, when transmitting the updated time information (referenceTimeInfo-r16) to the UE, the gNB cannot notify the UE that the time information has been updated. Therefore, it is difficult for the UE to recognize the timing of acquiring the SIB 9 including the updated referenceTimeInfo-r16. As described above, the UE can request time information from the network, but in this case, the gNB can transmit time information by SIB9 (broadcast) or DLInformationTransfer (unicast). Therefore, it is difficult for the UE to determine whether the time information is transmitted by SIB9 or DLInformationTransfer. Accordingly, the following disclosure has been made in view of such a situation, and it is an object of the present invention to provide a terminal capable of quickly and efficiently acquiring time information in an NR (5G) system. An embodiment of the present disclosure is a terminal (UE 200) provided with a control unit (control unit 250) that acquires time information used in a system from a network, and a reception unit (message processing unit 240) that receives a message indicating that the time information has been updated from the network, wherein the control unit acquires the time information in response to receiving the message. An embodiment of the present disclosure is a terminal provided with a transmission unit (time management unit 230) that transmits a transmission request of time information used in a system to a network, and a reception unit (radio communication unit 210) that receives a downlink channel to which the time information is transmitted after transmitting the transmission request. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an overall schematic diagram of a radio communication system 10. FIG. 2 is a functional block diagram of the UE 200. FIG. 3 is a diagram showing a configuration example of a ReferenceTimeInfo. FIG. 4 is a diagram showing a configuration example of OtherConfig and UEAssistanceInformation. FIG. 5 is a diagram showing an update sequence of time information according to operation example 1. FIG. 6 is a diagram showing an update sequence of time information according to operation example 2. FIG. 7 is a diagram showing a configuration example of DLInformationTransfer. FIG. 8 shows an example of a hardware configuration of the UE 200. MODES FOR CARRYING OUT THE INVENTION Exemplary embodiments of the present invention are explained below with reference to the accompanying drawings. Note that, the same or similar reference numerals have been attached to the same functions and configurations, and the description thereof is appropriately omitted. (1) Overall Schematic Configuration of the Radio Communication System FIG. 1 is an overall schematic configuration diagram of an radio communication system 10 according to this embodiment. radio communication system 10 is a 5 G New Radio (NR) compliant radio communication system and includes a Next Generation-Radio Access Network 20 (User Equipment 200, hereinafter UE 200), NG-RAN 20, and user terminal 200. radio communication system 10 may be a radio communication system that follows a scheme called Beyond 5G, 5G Evolution or 6G. The NG-RAN 20 includes a radio base station 100 (hereinafter, gNB 100). The specific configuration of radio communication system 10 including the number of gNBs and