The echo of ground penetrating radar （GPR） has a characteristic of large dynamic range. If the echo of GPR doesn＇t be processed and direct is adopted analog-to-convert, the dynamic range of analog-to-digital converter （ADC） in data acquisition circuit can＇t match the need of GPR system and the problem will affect the exploration depth and resolution of GPtL In order to solve the problem,a time varying gain （TVG） method which attenuates the strong signal reflected from shallow layer while amplifies the weak signal reflected from deep lay...
