What is GPR?
Basic Mechanism
•Pulses of EM waves are transmitted into/through soils & pavements and the strength of returning signals from encountering objects in the ground are recorded (nano second time scale)
•Changes in the electrical properties of the soil & targets induce “return” signals and the greater the difference in the dielectric properties between the materials produces a larger amplitude return signal
•Images in the form of parabolas are produced as the antenna (T & R) move over a target, such as a pipe—other types of images depend on the target shape