卫星导航信号畸变导致的测距偏差的估计方法

为定量评估导航信号的测距性能，本文研究了在轨卫星导航信号畸变导致的测距偏差估计问题。基于Vernier采样原理利用大口径抛物面天线采集在轨卫星导航信号，经数据处理获得一个伪码周期的脉冲波形。在此基础上，对该波形起点位置进行精确估计，然后根据延迟锁定环工作原理产生超前本地波形和滞后本地波形，获得E-L鉴别器曲线，最后估计鉴别器曲线的零交叉点偏差，该偏差即为卫星导航信号畸变导致的测距偏差。利用北斗卫星采集信号，获得了B1频点I支路信号的测距偏差，验证了该估计方法的正确性。

Estimation Method of Ranging Bias Caused by Navigation Satellite Signal Distortion

For quantitative evaluation of signal quality, a ranging bias estimation method of in-orbit satellite signals is proposed. Based on Vernier sampling, a large diameter parabolic antenna is used for in-orbit satellite signal collection, and a clear waveform for one code epoch is achieved after data processing. Base on the clear waveform, it’s starting point position estimation is made. According to the working principle of delay locked loop, leading signal and delay signal are produced to obtain E-L discriminator curve, then zero crossing bias is achieved through linear fitting, which is the ranging bias caused by signal distortion. Using the collected signal of one COMPASS satellite, the ranging bias of I channel of B1 band is obtained, so the estimation method is verified.