TABLE OF CONTENTS GPR has an enormously wide range of applications, ranging from planetary exploration to the detection of buried mines. The selection of a range of frequency operations, a particular modulation scheme, and the type of antenna and its polarisation depends on a number of factors, including the size and shape of the target, the transmission properties of the intervening medium, and the operational requirements defined by the economics of the survey operation, as well as the characteristics of the surface. The specification of a particular type of system can be prepared by examining the various factors which influence detectivity and resolution.
To operate successfully, ground penetrating radar must achieve:
an adequate signal to clutter ratio
an adequate signal to noise ratio
an adequate spatial resolution of the target
an adequate depth resolution of the target.
Most GPR systems detect the backscattered signal from the target, although forward transmission methods are used in borehole tomographic radar imaging.
This Chapter considers the principal factors affecting the design of a GPR in order to illustrate those factors which need to be considered. The aim is to illustrate the technical options available to the operator or designer. This is not a rigorous treatment of radar system analysis but does enable an order of magnitude estimate of the various loss components to be assessed. Many radar systems generate a fast rise time impulsive voltage, so the signal level is best considered from the point of view of voltages across particular nodes in the network.
