Microwave Mapping-Transparency Sensor System

ABSTRACT: Compass Technology Group (CTG) proposes to develop a new concept in microwave nondestructive evaluation (NDE) in support of the Air Force"s requirement for transparent conductive canopy coating testing. The offered design specifically addresses the need for high-fidelity measurements of defects in aircraft windows in both manufacturing and in-service (depot and field) environments. This recommended concept can be easily automated while still providing improved sensitivity over a broad frequency range when compared to existing measurement methods. The research program will investigate a modified free-space method that leverages recent near-field probe and free-space materials measurement technology. Full-wave computational modeling will be used to refine the measurement architecture during phase I, and computational-based antenna optimization methods will be used to design the probe configuration to maximize both bandwidth and probe efficiency. Unlike recent resonant probe designs, the proposed CTG solution uses wide-band antenna technology for optimal sensitivity without sacrificing bandwidth. Additionally, the proposed common architecture will be ideally suited for use in both manufacturing environments where quality assurance measurements are needed, as well as in depot or field environments (e.g. on installed cockpit canopies) where installed performance and damage assessment is the desired quantity. BENEFIT: If successful, this program will fulfill a critical Air Force need in manufacturing and maintenance of the next generation of conductive transparency systems. Such a development could also strongly impact other DoD services as well, since conductive windows and canopies exist across numerous platforms. Furthermore, other materials in use on DoD platforms require QA methodologies during manufacture, so the technology developed in this effort could very well be adapted to other similar materials manufacturing efforts for edge treatments and coatings on these vehicles. In Phase I, the proposed approach is intended to result in a viable design that meets the desired technical specifications for enhancing canopy and window performance while minimizing replacement rates and ultimately platform maintenance costs. The computational modeling tools and experimental demonstrations that will be applied by the Compass team will establish at a high level of fidelity, the feasibility of our proposed approach.