Microwave imaging using ultra wideband frequency-domain data

This article describes an ultra wideband (UWB) microwave system that uses the frequency-domain reflection coefficient data acquired by a UWB antenna to form a microwave image of a homogenous cylindrical dielectric body containing cylindrical targets. Both hardware and signal processing aspects of the system are described. The system uses a frequency-domain image reconstruction algorithm using the different data obtained for adjacent positions of the scanning antenna so that the effect of air-image body interface is removed. The algorithm is tested in examples of a cylindrical dielectric container including a vegetable oil and targets in the form of small-diameter plastic straws filled with water. Both simulated and measured results are presented. The successful detection and location of the targets is achieved by visual inspection of the formed microwave images.