基于最优双正交小波基的地质雷达信号定量分析方法

摘要

现有的地质雷达信号定量分析方法易受反射波干涉和回波噪声等因素的影响,存在明显的不稳定性、局限性和准确性差等问题.本文针对地质雷达信号和小波时-频分析的固有特点,运用改进的双正交小波构造方法,构造用于地质雷达信号定量分析的最优双正交小波基(GPR3.3小波基),提出了基于双正交小波基的地质雷达信号定量分析法(QAGBW法),并将该法应用于模拟信号和实测信号的定量分析中.分析结果表明:与Bayesian频率域盲反褶积和现有小波基相比,基于最优小波基的QAGBW法能够有效抑制反射波干涉和回波噪声等因素的干扰,提高地质雷达信号定量分析精度,并使定量分析的最小厚度与地质雷达的垂直探测分辨率相匹配.%Due to the disturbances arising from the coherence of reflected waves and from echo noise,problems such as limitations,instability and poor accuracy exist with the current quantitative analysis methods.According to the intrinsic features of GPR signals and wavelet time-frequency analysis,an optimal wavelet basis named GPR3.3 wavelet is constructed via an improved biorthogonal wavelet construction method to quantitatively analyse the GPR signal.A new quantitative analysis method based on the biorthogonal wavelet (the QAGBW method) is proposed and applied in the analysis of analogue and measured signals.The results show that compared with the Bayesian frequency-domain blind deconvolution and with existing wavelet bases,the QAGBW method based on optimal wavelet can limit the disturbance from factors such as the coherence of reflected waves and echo noise,improve the quantitative analytical precision of the GPR signal,and match the minimum thickness for quantitative analysis with the vertical resolution of GPR detection.