Optimization of frequency-diverse antennas for computational imaging at microwave frequencies

Frequency-diverse imaging is an all-electronic method, capable of sampling the scene to be imaged without the need for a mechanical scan or active circuit components. In order to optimize the imaging characteristics, such as imaging resolution and fidelity of the reconstructed images, the antennas used within this scheme need to be optimized. It is demonstrated that using a Mills-Cross iris distribution, superior sampling of the Fourier components (wide support extent and minimum sampling redundancy) can be achieved. Using the optimized antennas, an experimental imaging system is built, reconstructing a good quality image of a cross-shaped target in less than 0.1 seconds.