基于DVB-S的数字卫星电视授时方法研究

Study on digital satellite-television time-service based on DVB-S

介绍一种基于DVB-S标准的数字卫星电视高精度时间传递方法。在此方法中,以电视信号中的PCR(节目时钟参考)作为标志位,在发播台和接收端实时记录PCR发播和接收的精确时间戳,使得接收端与发播台时间实现粗同步,再利用精密卫星星历以及接收点的位置等信息计算实时路径传播时延使其达到高精度同步。经过试验验证,该方法是可行的并且其时间同步精度优于100 ns(1σ)。

A high-precision time transfer method via digital satellite-television system, which is based on DVB-S standard, is introduced. The PCR(program clock reference) in television signals is taken as a mark and the time-stamps both for broadcasting and receiving are recorded in time at the broadcasting station and receiving terminal, thus gross time-synchronization between the broadcasting station and receiving terminal is realized. Afterwards, the length-propagation delay is estimated by using the information such as precise satellite ephemeris and receiver location, thus high precision time-synchronization is reached. The tests have verified that this method is workable and the time-synchronization precision is better than 100 ns(1 ?)。