导航卫星导航信号发射通道的设备自身时延是星地组合时延的一个组成部分,在实际定位和授时应用中必须扣除,因此,卫星在地面测试中必须进行通道零值标定。通道的零值测试精度将直接影响用户的测距精度和时间传递精度。文中给出一种采用数字域部分相关处理技术的导航卫星BOC(binary offset carrier)信号发射通道零值测试方法,对BOC信号和导航卫星秒脉冲1PPS (1 Pulse Per Second)信号高速率同步采样,对BOC信号采样数据进行载波相位相关处理,积分时间低于一个伪随机码周期,处理后得到采样数据中伪随机码起始点,结合1PPS采样数据,计算得到BOC导航信号发射通道的零值。采样频率10 GHz时,提出测试方法的测量不确定度优于0.2 ns。
Abstract:
The delay caused by signal transmission channel of navigation satellite is a part of the total delay of the satellite-to-earth link,and it must be deducted in the actual positioning and timing applications. Delay measurement of satellite channels must be carried out in ground tests. Test accuracy of the channel delay will affect users ranging accuracy and precision time transfer. A BOC(binary offset carrier) signal channel delay measuring technique using partial correlation is proposed. BOC navigation signals and 1 PPS(1 pulse per second) signal are high-speed synchronous sampled. Partial correlation processing is made for the sampling BOC signal data and the integration time is less than a pseudo-random code cycle. The starting point of the pseudo-random code sampling data obtained by processing,then the transmission channel delay of the BOC navigation signals can be calculated. The uncertainty of the test method is less than 0.2 ns for sampling frequency of 10 GHz.