Method of amplitude and phase correction of GPR system transient response

Abstract

In this report a method of frequency- and time-domain GPR signal processing is proposed for increasing the detection probability for objects with weak contrast, especially for layer boundaries with non-sharp changes of dielectric permittivity. The method consists of amplitude and phase correction either on receiver input or digitally on its output (after scaling of input signal spectrum by stroboscopic converter). Such filtration can suppress interference due to finite damping of antenna transient response (exponential decrease of signal oscillation amplitude), signal reverberations in feeder lines (constant amplitude of oscillations) and between antennas in air (t-c decrease of amplitude). A complex coefficient is defined in frequency domain, which allows to transform the spectrum of mean signal to gauss-like spectrum. Then, in time domain after the filtration signal waveform is similar to Rieker wavelet and has almost no oscillations. This can increase the reliability of detection of weak reflections overlapped with late time oscillations of direct coupling signal.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.