Experimental Detection of Pipeline Leaks with a 3-D Subsurface Imaging Radar

Pipeline leaks detection is an important problem in water transport systems maintenance. Bistatic subsurface synthetic aperture (SAR) radar is a promising tool that could be used to detect leaks due to the radar’s ability to illuminate the underground from multiple directions. However, a major obstacle preventing leak detection is the dominance of the scattered signal from the pipeline compared to the leak signal. Utilizing the different scattering mechanisms exhibited by the pipeline and the leak, this paper proposes a technique that identifies the pipeline part in the radar signal and eliminates it leading to better leak detection. The radar response of water leaks out of metallic as well as plastic (PVC) pipes is measured with a pair of ENVELOP antennas designed for subsurface radar and a por table Vector-Network-Analyzer (VNA). Processing the measurements using the proposed technique shows a significant improvement in leak detection for both the metallic and the PVC pipe cases.