Simulation System for Planar Aperiodic Cavity Imager Based on Compressed Sensing

By acquiring compressed information directly, the compressed sensing theory provides a method to reconstruct signals from few sampled data. Based on this theory, a microwave imaging simulation system working at K-band frequencies (18-26.5GHz) was designed. The system consists of a planar cavity transmitting aperture with aperiodic radiating circular irises and a set of low-gain horn receiving antennas. These aperiodic irises bring a disorganized field distribution at the scene to satisfy the specific requirements of compressive sampling. Hardware in the loop (HIL) simulation was applied to design and optimize the imaging system by using the computational electromagnetics software FEKO. In addition, the sparsity adaptive matching pursuit (SAMP) algorithm was used to reconstruct signals from the compressive sampled data, and highly resolution results were obtained. Primary results demonstrated that the system is effective to perform imaging at the scene. Without any unhandy mechanically moving parts or complex phase shifting networks, this imaging mechanism may possess a good application prospect in security inspection field.