Microwave imaging systems employing cylindrical, hemispherical and planar arrays of ultrawideband antennas

The construction and operation of three ultrawideband microwave imaging systems aimed for biomedical applications such as detection and location of breast tumor is presented. The first system utilizes a cylindrical array of antennas that are connected with a vector network analyzer via a set of microwave switches. The system is arranged so that it can operate as monostatic or multistatic radar. In the second system, the antenna array is arranged in a hemispherical configuration for a high spatial scan resolution. The third system employs planar array of antennas to collect the backscattered signals from the imaged object. In all these systems, corrugated tapered slot antennas are used due to their directive properties, low profile, and compact size. In order to test the reliability of the developed systems for breast cancer detection, a number of breast phantoms are designed and manufactured. The measured electrical properties of these phantoms confirm successful emulation of the properties of realistic tissues. A coupling liquid is also designed and fabricated in order to improve the matching between the antenna arrays and the breast phantom, and thus to increase the dynamic range of the imaging systems.