On study of an impulse RADAR sensor for subsurface object detection

Subsurface object detection can be an important tool for construction industry and utility companies. For instance, knowing the location of a steel bar or a steel pipe without any physical penetration of walls, floors, or ground can greatly save cost and time for construction and utility workers in their excavation. In this work, a prototype of an impulse RADAR sensor is developed and studied. Based on the concept of ground penetrating RADAR (GPR), a Gaussian monocycle pulse is generated with a pulse duration of 3.5 ns and amplitude of 1.47 Vpp, and used as a probe signal for the impulse RADAR sensor. Three types of wideband antennas are also developed and compared in this work. Then, the system is tested for its ability, using B-scan images, to detect a section of round steel bar with a length of 14.5 cm and a cross section of 0.9 cm at a depth of 20 cm under a sand surface inside a sand box.