探地雷达信号的KL变换处理分析

实测探地雷达记录中存在大量的噪声干扰,有时致使目标信号难以分辨,为提高雷达剖面的信噪比,主要探讨KL变换在消除干扰噪声方面的有效性.在说明KL变换原理的基础上,通过Matlab软件进行编程计算,对时域有限差分法获得的探地雷达模拟剖面和现场实测雷达数据进行处理;再对处理前后的雷达图像进行对比分析.经过处理分析可知,KL变换可压制模拟数据中边界反射信号和棱角点的绕射波、抑制和消除实测雷达剖面中的高频杂波噪声信号,从而突出有效信号,增强有效信号的相对强度,这提高了探地雷达剖面的分辨率和反演解释精度.

Signal processing of ground penetrating radar by KL transform

There is large amount of noise in the ground penetrating radar (GPR) record, which causes the target signal to be distinguished with difficulty at times. In order to increase SNR of GPR sections, the validity of KL transform to remove noise in GPR record was discussed. On the basis of KL transform theory, the calculating program was written out in Matlab environment. The GPR modeling record of finite difference time domain method and real data were processed by KL transform, the results were analyzed and compared with original records. According to the analyzing results, KL transform suppress boundary reflection signals and corner diffraction signals of modeling data, and remove high frequency noise in GPR real data. After the transformation the effective signals are intensified, and resolution of GPR sections and inversion accuracy are improved.