UWB microwave imaging system including circular array antenna

The paper describes the design of an ultra wideband (UWB) microwave imaging system employing a 12-element circular array antenna. The array uses compact tapered slot antenna (TSA) elements operating over 3.1-10.6 GHz band. The elements of the array are activated by two coaxial SP6T switches that are connected to a vector network analyser (VNA) to achieve monostatic or multi-static radar modes of operation. In addition, the array is moved using a mechanical cylindrical scanning subsystem. This electronic/mechanical sub-system allows a fast high-resolution scan of an imaged object. The paper describes the reasons for choosing this particular imaging system configuration and provides full construction details. Also shown are the imaging results of a circular plastic container filled with a vegetable oil and small diameter circular cylindrical targets using a novel image reconstruction algorithm.