岸基GPS海面反射信号提取方法及特性分析

Extracting method and characteristic analysis of coastal GPS signal reflected from sea surface

岸基全球定位系统(global positioning system,GPS)海面反射信号特性对GPS反射信号遥感反演具有重要意义,可为系统设计提供重要参数支持。在实验数据的基础上对微弱GPS海面反射信号特征提取方法进行验证和分析,结果显示所采用的提取方法能够有效提取海面反射信号;分析不同积分时间相干积分和非相干积分的性能,结果显示,积分时间在100ms以上时,相干积分和非相干积分都能有效提取反射信号特征,且两者得到的信噪比基本一致;海面反射的GPS信号符合高斯分布特征,这与已发表文献的结论是不同的;两次连续测量反射信号的功率变化有90%的概率超过6dB。

The characteristics of global positioning system （GPS） reflections from sea surface collected by a coastal static platform are of crucial importance for remote sensing and retrieval, which can provide necessary parameters for system design. A method which is used to get the characteristics of weak GPS reflections is examined and analyzed based on experiment data, and the results show that the method is feasible. The perfor- mances of coherent and non-coherent integration with different integration times are also investigated in detail, and the results show that both of the two integration algorithms can significantly extract the reflections, and the signal-to-noise ratio obtained from the two algorithms is basically similar, when the integration time is more than 100 ms. The statistical characteristics of GPS reflections are Gauss function, which is different from those results obtained from other references. Moreover, the difference between two successive measurements of re- flections can differ significantly as expected, which is at least 6 dB with a probability up to 90%.