Monopole antenna integrated cavity resonator for microwave imaging

Abstract

We present a system that displays an image of any metal structure in a scene by the use of microwave radiation from a cavity resonator in a 10-GHz frequency band. An 80 mm x 80 mm mushroom-like electromagnetic band gap (EBG) structure was arranged, designed, analyzed, and integrated with an X band monopole antenna and the designed EBG monopole antenna has similar to 2-GHz bandwidth. Meanwhile, a cubic cavity resonator is constructed and an EBG grounded monopole antenna is located on one wall of the cavity resonator to create a narrow band radiation. The formed narrow band radiation from the cavity resonator reaches to the metal structure located in the scene. Backscattered radiation collected by a 8 to 12 GHz waveguide receiver that is located near the cavity to scan the whole scene and sweep the waveguide throughout the resonator plane performs to gather various transmission values from a scene. These various transmissions from the cavity resonator antenna to the waveguide receiver were used for imaging. In addition, tunability of the designed EBG structure is studied and presented. The designed structure has advantages such as easy design and fabrication, high accuracy performance, and compatibility to the other frequency regimes. In addition, the designed EBG plane is based on RLC circuit theory, which enables us to understand the antenna performance and EBG structure. This system can be integrated with various areas, such as medical imaging, military applications, weapon detections, security imaging purposes, stealth technology, and other appropriate applications.