输入输出相关处理的RDSS通道零值测试

为了准确测量无线电测定业务(RDSS)通道零值,提出一种基于循环相关处理的测试方法.采用真实的RDSS信号作为测试信号,对导航卫星RDSS业务通道输入和输出进行同步过采样,然后对采样后的输入和输出信号进行希尔伯特变换、载波旋转,对载波旋转后输入输出信号进行循环相关处理,搜索相关峰值,由峰值点确定循环位移量,最后结合采样频率和测试系统的标校时延,计算得到了RDSS业务通道零值.提出的测试方法采样频率10GHz时,其测量不确定度优于0.2ns.

Delay measurement of RDSS channel using correlation between input and output signals

In order to accurately measure the absolute delay of the radio determination satellite service（RDSS） channel, a measurement technique was proposed based on the circulating correlation. The real RDSS signal was used as the test signal. The input signal and the output signal of the RDSS channel were high-speed synchronously collected and then precessed with Hilbert transformation and carrier rotating and the circulating correlation. The cyclic shift amount was determined by searching the peak of the circulation correlation. Finally, the absolute delay of the RDSS channel was calculated combining the sampling frequency and the calibration of the test system. The uncertainty of the proposed technique is less than 0.2 ns for the sampling frequency of 10 GHz.