小波基在GPS-IR反演土壤湿度中优选方法的研究

Research on the preferred method of wavelet base based on GPS-IR inversion of soil moisture

全球定位系统多径干涉遥感技术(Global Positioning System-Interference Reflection,GPS-IR)是一种基于卫星反射信号的新遥感技术,可实现土壤湿度、雪深、海平面等方面的监测.针对卫星反射信号分离问题,本文利用小波分析对信噪比(Signal-to-Noise Ratio,SNR)中的卫星反射信号进行分离.小波基的选择直接影响到卫星反射信号分离的效果,本文通过对比低阶多项式、sym10、bior6.8、dmey和coif5这5种方法的实际消趋和反演效果来优选.经实验表明:利用coif5小波基分解6层能够有效提高卫星反射信号的分离精度和信号的分辨率,获取的相对延迟相位与土壤湿度之间的线性关系显著增强.

Global Positioning System-Interference Reflection(GPSIR)is a new remote sensing technology based on satellite reflection signals,which can monitor soil moisture,snow depth and sea level.For the problem of satellite reflection signal separation,this paper uses wavelet analysis to separate the satellite reflection signals in the Signal-to-Noise Ratio(SNR).The choice of wavelet basis directly affects the separation effect of satellite reflection signals.This paper compares the actual elimination and inversion effects of the five methods of low-order polynomial,sym10,bior6.8,dmey and coif5.Experiments show that the decomposition of 6 layers by coif5 wavelet base can effectively improve the separation precision and signal resolution of satellite reflection signals,and the linear relationship between the relative delay phase and soil moisture is significantly enhanced.