接收机锁定卫星信标后,经过二次或三次变频将C频段信标转变为70 MHz中频,然后通过解调单元从中频中提取误差信号。通过分析比较信标信号、L频段频率、70 MHz中频信号频谱使跟踪系统的性能指标层次化,从信标频谱中提取有用信息,全面判断数字接收机跟踪性能,对单脉冲跟踪体制下的接收机故障排查具有一定的指导意义。

After tracking receiver has locked satellite beacon,it translates intermediate frequency of 70 MHz from C-frequency by twice or thrice frequency conversion. Then,error signal is extracted from intermediate frequency via demodulation unit. It makes performance index of tracking system hiberarchy by means of analyzing beacon signal, L-frequency and intermediate frequency of 70 MHz. At the same time, some useful information can be extracted from beacon signal, to estimate digital tracking performance of receiver comprehensively. It has a direction significance for fault detection of single-impulse tracking system receiver.