Research On Imaging Methods Of Pulse Ground Penetrating Radar

Ground penetrating radar(GPR)is an effective tool for the detection of underground targets,which has the advantages of fast detection speed,high resolution,strong penetrating power and nondestructive detection.Ground penetrating radar data imaging is the synthetic aperture processing of the received echo signal,which is helpful for the location and detection of underground targets.This paper mainly studies the commonly used methods of GPR imaging,the specific contents include the following aspects:(1)According to the sources of clutter echo from echo signal model,clutter suppression method such as average method,K-L transform method and wavelet denoising method of clutter suppression methods were both studied.aiming at the existing problems of traditional threshold function,an improved threshold function was proposed.The evaluation index of clutter suppression effect was established.(2)An improved back projection imaging based on sub-aperture was proposed.The evaluation parameters of quantitative imaging effect were established and synthetic aperture imaging was carried out using simulation and measured data respectively,showing that the improved back projection imaging algorithm not only improves the efficiency of calculation,but also improves the image quality.(3)The influence of the wave velocity on the imaging was analyzed.The minimum entropy method combined with frequency-wavenumber migration imaging to estimate the wave velocity is emphasized,and the feasibility of the minimum entropy method was proved by the simulation and experimental data.GPR imaging software based on MFC was developed,and imaging processing over measurement was carried out.