Communication device and communication method
[Object] To provide innovation with respect to which synchronization signal a communication device uses to conduct a synchronization process. [Solution] Provided is a communication device including: a selection unit configured to select a synchronization signal from respective synchronization signals received from two or more other devices on a basis of origin information that is acquired by communication with another device and that indicates an origin of a synchronization signal used for acquisition of synchronization timing in the other device; and a synchronization processing unit configured to acquire synchronization timing using the synchronization signal selected by the selection unit.
1. A communication device comprising:
a selection unit configured to select a synchronization signal from respective synchronization signals received from two or more other devices on a basis of origin information that is acquired by communication with another device and that indicates an origin of a synchronization signal used for acquisition of synchronization timing in the other device; and
a synchronization processing unit configured to acquire synchronization timing using the synchronization signal selected by the selection unit, wherein
the origin information includes information corresponding to a source device serving as a source of a synchronization signal for the acquisition of the synchronization timing in the other device,
the selection unit recognizes a source device corresponding to a synchronization signal received from the other device on a basis of the origin information, and prioritize, among a synchronization signal corresponding to a first source device and a synchronization signal corresponding to a second source device according to a system that provides service in a wider range compared with the first source device, selection of the synchronization signal corresponding to the second source device,
the first source device is a cellular base station, and the second source device is a GPS satellite.
2. The communication device according to claim 1 , wherein
the origin information includes information that indicates a procedure of relaying the synchronization timing from the source device to the other device.
3. The communication device according to claim 2 , wherein
the origin information includes number-of-interpositions information that indicates a number of interposing devices in the procedure of relaying the synchronization timing from the source device to the other device.
4. The communication device according to claim 3 , wherein
the selection unit recognizes a number of interposing devices in a relaying procedure corresponding to a synchronization signal received from the other device on a basis of the number-of-interpositions information, and prioritize, among a synchronization signal corresponding to a first relaying procedure and a synchronization signal corresponding to a second relay procedure having a larger number of interposing devices compared with the first relaying procedure, selection of the synchronization signal corresponding to the first relaying procedure.
5. The communication device according to claim 1 , wherein
the origin information includes score information calculated on a basis of the origin of the synchronization signal used for acquisition of the synchronization timing in the other device, and
the selection unit selects the synchronization signal on a basis of a magnitude relationship of score information corresponding to a synchronization signal received from the other device.
6. The communication device according to claim 1 , further comprising
a control unit configured to determine whether or not to transmit a synchronization signal after the acquisition of the synchronization timing by the synchronization processing unit on a basis of origin information of a synchronization signal selected by the selection unit.
7. The communication device according to claim 6 , wherein
the origin information indicates a number of interposing devices in the procedure of relaying the synchronization timing from a source device to a transmission source device of a synchronization signal selected by the selection unit, the source device serving as a source for a synchronization signal for acquisition of synchronization timing in the transmission source device, and
the control unit determines not to transmit the synchronization signal in a case where a number of the devices exceeds a threshold value.
8. The communication device according to claim 1 , further comprising
an acquisition unit configured to acquire an ID for generating a synchronization signal received from the other device as the origin information.
9. The communication device according to claim 1 , further comprising
an acquisition unit configured to acquire the origin information from system information to be transmitted from the other device.
10. The communication device according to claim 2 , wherein
the selection unit decides which synchronization signal corresponding to origin information to select in accordance with a movement condition of the communication device.
11. The communication device according to claim 10 , wherein
the selection unit uses a lane ID that indicates which road the communication device has moved along as a movement condition of the communication device.
12. The communication device according to claim 1 , wherein
the selection unit decides which synchronization signal corresponding to origin information to select in accordance with an instruction from an external device.
13. The communication device according to claim 1 , wherein
the selection unit decides which synchronization signal corresponding to origin information to select using information to be provided from an external device.
14. A communication method comprising:
selecting, by a processor, a synchronization signal from respective synchronization signals received from two or more other devices on a basis of origin information that is acquired by communication with another device and that indicates an origin of a synchronization signal used for acquisition of synchronization timing in the other device; and
acquiring synchronization timing using the selected synchronization signal, wherein
the origin information includes information corresponding to a source device serving as a source of a synchronization signal for the acquisition of the synchronization timing in the other device,
the selecting includes recognizing a source device corresponding to a synchronization signal received from the other device on a basis of the origin information, and prioritize, among a synchronization signal corresponding to a first source device and a synchronization signal corresponding to a second source device according to a system that provides service in a wider range compared with the first source device, selection of the synchronization signal corresponding to the second source device,
the first source device is a cellular base station, and the second source device is a GPS satellite.