GPS系统多普勒频移估算的研究

在GPS导航定位系统中,多普勒频率偏移直接影响接收机性能。为了克服多普勒频率偏移的影响,提高接收机的GPS信号捕获速度,对多普勒频移估计算法进行了研究。推导了导航卫星运行参数的数学模型,给出多普勒频移估算的数学模型,对导航卫星运行参数及多普勒频移特性进行了MATLAB仿真。结果表明,卫星与接收机之间的相对位置对信号的多普勒频移特性有着较强的影响。仿真结果可以为多普勒频移的估计和补偿提供先验信息。

Research on Doppler Frequency-shift Estimation of GPS

In the satellite navigation and positioning system,Doppler frequency-shift is the key problems that degrade the performance of satellite receiver.To overcome the influence of Doppler frequency-shift and improve the speed of GPS signal acquisition,the paper first studies the algorithm of Doppler frequency-shift estimation,and then deduces the mathematic models of satellite movement paremeters and Doppler frequency-shift estimation.Finally,the algorithm models are simulated in MATLAB simulation environment.The result shows the relative position between the satellite and the receiver has a relatively strong effect on the characteristic of Doppler frequency-shift which can be used for estimation and compensation of Doppler frequency-shift.