Synchronization for vehicle (V2X) communications
A wireless terminal comprises sidelink controlling circuitry and transmitting circuitry. The sidelink controlling circuitry is configured to select a reference source. The transmitting circuitry is configured to transmit sidelink synchronization signal (SLSS) based on the reference source. In a case that a timing reference is Global Navigation Satellite System (GNSS) and the GNSS is reliable according to a comparison with a threshold value, the sidelink controlling circuitry is configured to select GNSS as the reference source.
1. A wireless terminal comprising:
sidelink controlling circuitry configured to select a reference source; and
transmitting circuitry configured to transmit a sidelink synchronization signal (SLSS) derived from the reference source;
wherein in a case that
the wireless terminal is out of coverage on a frequency used for sidelink communication,
the wireless terminal receives Global Navigation Satellite System (“GNSS”), and
the GNSS is reliable according to a comparison with a threshold value,
a timing acquired from the GNSS is selected as the reference source.
2. A method of operating a wireless terminal comprising:
selecting a reference source;
transmitting a sidelink synchronization signal (“SLSS”) derived from the reference source;
wherein in a case that
the wireless terminal is out of coverage on a frequency used for sidelink communication,
the wireless terminal receives Global Navigation Satellite System (“GNSS”), and
the GNSS is reliable according to a comparison with a threshold value, a timing acquired from the GNSS is selected as the reference source.