What are the advantages of a digital GPR system over an analog system?
GPR systems must acquire very rapidly changing radio frequency signals. The capture of these signals for analysis and interpretation requires a considerable degree of electronic sophistication such that high fidelity data are acquired. Commercial GPR use equivalent time sampling (ETS) to capture the transient radio wave signals. ETS uses the same principles as a stroboscope. In its earliest form, analog electronic circuitry was designed to translate the rapidly varying GPR voltage into an audio frequency signal that could be recorded and displayed. With time, GPR technology of signal capture with ETS has evolved substantially. Key developments over the past 30 years have been as follows. (a) Recording the analog audio frequency signal on analog audio tape recorders for replay. (b) Digitizing of the analog audio frequency signal to record the data on digital magnetic tape or computer disks. Computers are used for replay and analysis. (c) Elimination of audio instrument stage with direct
