Research
Positioning, Navigation, and Timing (PNT) for Mobile Distributed Radar Networks
Future airborne distributed radar systems require precise relative navigation and synchronization to enable coherent operation. Our research on this topic advances the state-of-the-art in all-digital algorithms for high-precision navigation and synchronization for coherent distributed radar operation, with an emphasis on low size, weight, and power (SWaP) platforms and environments with limited access to GPS.
Cooperative Autofocus for Multi-Aperture Synthetic Aperture Radar (SAR)
High-fidelity SAR imaging requires sub-wavelength level navigation precision. When this cannot be achieved, images become smeared, and algorithms called autofocus must be applied to correct residual phase errors. Our research on this topic develops autofocus algorithms for multi-aperture volumetric SAR imaging to correct relative navigation- and synchronization-based phase errors, and seeks to incorporate phase error function products from autofocus into a cooperative framework for navigation and synchronization.
Test Equipment for Low-Cost Lab Testing of Radar Systems
Before field deployment, radar systems must be tested against scenery with a verifiable response. Considering the cost of testing deployments, lab-testing of systems is a cost-effective alternative, particularly in the case of testing mass-produced systems. Our research on this topic introduces new approaches to radar target simulation for high-fidelity scene emulation for wideband systems. We are also developing novel methods for performing “navigation-in-the-loop” testing of moving radar systems, enabling lab-based testing of airborne radar systems, such as SAR systems, including the GPS and inertial components of the navigation system.
Computational Techniques for Design and Tuning of Microwave Filters
Microwave filters are critical components in modern radio systems which must operate in an increasingly congested electromagnetic spectrum. Filter design is often confounded by the practical effects of high-frequency electromagnetics, which produce unmodeled loading and parasitic effects and cause the realized filter response the deviate from the desired response. Our research on this topic is developing novel time-domain techniques based on the unscented Kalman filter (UKF) for efficient tuning of filter designs, both in simulation during the design and in post-fabrication tuning.