A Research Of The Key Technologies In Ground Penetrating Radar

Ground Penetrating Radar (GPR) is an underground testing technique that determines the depth and shape of the underground media by launching ultra-high frequency pulse electromagnetic wave and analyzing the electromagnetic echo reflected. GPR combines Electromagnetic Field Theory. Antenna Design, RF Circuit, Signal Processing and the research results of many other fields. Because it has these technical characteristics of continuous detection, simple operation, non-destructive detection to the detected objects and underground targets fast imaging, its application prospects are very broad in the military and civilian fields.This paper first reviews the history and the nowadays development status of the GPR. Then based on the studies of an analysis of its working principle, a system design plan for GPR is given. The plan is focused on the study of echo signal sampling and sampling circuit implementation. Ground Penetrating Radar uses equivalent time sampling technique. Sampling circuit includes two parts of the sampling pulse generator and sampling gate, the generator produces sampling pulse by the incentive of the step-delay pulse. And then the sampling pulse is loaded into the bridge circuit consisting of a balanced gate, which composes by4step recovery diodes. Finally, the sampling of the echo signal is completed. By comparing with and imitating the sampling circuit of SQ27sampling oscilloscope, the sampling circuit for GPR has been completed.