An Evaluation of Millimeter-wave Radar Sensing for Civil Infrastructure

Critical infrastructure is a dense network of systems that provide vital services such as energy, transport and water. Continuous cycles of monitoring and repair are vital to the economic development and functions of a community. Current detection methods of subsurface fault precursors in civil infrastructure are insufficient for subsurface defect detection. In this paper we present the analysis of complex multi-layer structures with radar, Frequency Modulated Continuous Wave (FMCW) sensing. Results have demonstrated the ability of K-band analysis to detect embedded and obscured materials during inspection by detecting contrasts in the return signal amplitude from the sensor. This includes detection of the depth and geometry of subsurface materials and detection of water ingress within materials. Thus, we propose that FMCW analysis represents a novel method of non-invasive, non-contact and non-destructive analysis of dielectric and multi-layer materials applicable to asset integrity and health monitoring for the civil infrastructure sector. This research ensures that inspection engineers have tools available which can provide quantitative and qualitive results enabling more effective assessment of the subsurface integrity of a structure. The FMCW sensing modality provides early prognostics and remedial action to be taken, reducing the downtime of an asset and risk of failure.