Designing a SODAR testbed for RADAR applications

Abstract

In research there exists a need to constantly test and develop systems. Testing a radar system requires costly resources in terms of equipment and spectrum. These challenges relegate most testing to simulations, which are a poor approximation of reality. An alternative to over-the-air radar testing is presented here in the form of an over-the-air ultrasonic detection and ranging (SODAR) system. This system takes advantage of the similar wave-like propagation properties of acoustic and electromagnetic waves. With a sodar testbed, radar waveform design can quickly move out of simulation and into the real world with minimal overhead. In this thesis, basic and advanced radar sensing are demonstrated with a sodar setup. Range detection, Doppler sensing, and pulse compression are shown as examples of basic radar concepts. These basic radar tests prove that the fundamentals of radar also work with a SODAR setup. For advanced sensing applications, array-based direction finding and synthetic aperture radar (SAR) are shown. The direction-finding portion resolves three separate transmission sources with an 8-channel array. The thesis continues with a demonstration of SAR collections on multiple objects and culminates with a SAR image of a complex small-scale vehicle.