Wave-based techniques for detection and imaging

Abstract

The field of wave-based sensing covers a wide range of applications where measurements of a signal carried on propagating waves are used to learn about the environment. Sensing can be either passive, where a measured signal's source is external from the measurement system, or active, where a measurement system generates its own signal. Both passive and active sensing are challenging fields requiring steady incremental contributions in order to advance. In the pages that follow, I will present my own contributions to this challenging field. First, I detail work which addresses the problem of passively detecting an unknown signal in noisy measurements. My results allow for a quantification of the relationship between passive detection performance and the level of knowledge about the unknown measured signal. Then, I develop and analyze techniques for reducing computational cost and increasing performance of physics-based imaging techniques in radar applications. My results and technique prove to be a key ingredient in the first successful application of a technique to realistic real-world radar data. Finally, I design and test a method for improving existing radar imagery using a more accurate physics-based imaging technique. The results of my tests show a clear visual improvement in image quality.