Research On Signal Processing Algorithm Of Ground Penetrating Radar

Ground penetrating radar is a means of ground detecting equipment based on the theory that electromagnetic wave reflects at the inhomogeneous interface.Owing to its advantages of high efficiency,non-destructive and high resolution,it is widely used in pavement detection,urban construction,geological research,military reconnaissance,medical imaging and other fields.This thesis focus on the clutter suppression algorithm and synthetic aperture imaging algorithm of GPR echo.The specific work around the institutes is as follows: 1.Based on A-Scan data form,the echo is presented in B-Scan form by MATLAB,and then the hyperbolic characteristic of GPR point target is verified and analyzed.2.A series of preprocessing algorithms for GPR echo are studied,including simple noise suppression algorithm,direct wave removal algorithm,zero deviation correction algorithm and wavelet threshold de-noising algorithm.Then the simulation data and the measured data are used to verify these algorithms by MATLAB.3.For the sake of solving the shortcoming of wavelet threshold de-noising algorithm,the joint de-nosing algorithm is proposed to filter the low-frequency part after wavelet decomposition,so that the signal-to-noise ratio of echo is improved.4.The echo after preprocessing is processed by the back projection imaging algorithm.For the disadvantages of the original BP algorithm,such as clutter suppression,side lobe deficiency and long operation time,a window function based BP algorithm and a fast BP algorithm areverified separately to overcome them.A fast BP algorithm based on window function is proposed to solve the problem of clutter suppression and large computation concurrently.