数字域谱估计的GNSS系统信号带宽测试方法

针对传统的单载波扫频法不适于GNSS（全球导航卫星系统）信号生成通道的带宽测量的问题,提出了采用数字信号处理的信号带宽方法.对实际导航信号进行高速采样,在数字域对采样的导航信号和本地数字生成的理想导航信号进行频谱估计和计算,从而得到GNSS信号带宽.分别使用周期图法和Welch法谱估计,对提出的测试方法进行仿真.仿真结果表明,采用Welch法进行理想信号和实际信号谱估计,对谱估计后的结果进行计算,可以完成GNSS信号带宽精密测量,在Welch法估计参数设置合理的情况下,GNSS信号带宽估计的准确度可以达到99.9％以上.

Measurement of the Signal Bandwidth of GNSS Systems Using Spectrum Evaluation in the Digital Domain

A signal bandwidth method using digital signal processing technology is proposed for measurement of the bandwidth of the signal generation channels of GNSS （Global Navigation Satellite System） systems as the traditional single-carrier frequency sweeping method is not suitable.After high-rate sampling of a GNSS signal,the spectrum of the actual GNSS signal and the ideal signal generated locally are evaluated in the digital domain.Simulation is done for the proposed measurement method using spectrum evaluation algorithm of periodogram and Welch method.The simulation results show that the GNSS signal bandwidth can be accurately measured as long as the spectrums of the ideal and actual signals are evaluated and calculated using Welch method.The GNSS signal bandwidth measurement accuracy is over 99.9 ％ if Welch evaluation parameters are set properly.