Antenna configurations for Ultra Wide Band radar detection of breast cancer

Ultra Wide Band (UWB) radar is a promising emerging technology for breast cancer detection that makes use of the dielectric contrast between normal and tumour tissues at microwave frequencies. An important consideration in UWB imaging system design is the configuration of the antenna array. Two antenna configurations have been previously proposed to image the breast: the planar and the circular distributions. The planar configuration involves a 2D array of antennas placed on the naturally flattened breast with the patient lying in the supine position. Conversely, the circular configuration involves the patient lying in the prone position, with the breast surrounded by a circular array of antennas. In this paper, the two different configurations are compared using various metrics, including the minimum number of antennas needed to successfully detect the presence and location of tumours of different sizes in the breast. In order to effectively test both supine and prone imaging approaches, two 2D Finite-Difference Time-Domain (FDTD) models of the breast are created. The backscattered signals recorded from each antenna configuration are passed through a simple delay and sum beamformer and images of the backscattered energy are created. The images obtained using both antenna configurations are compared and the performance of each imaging approach is evaluated by quantitative methods and visual inspection, for a number of test conditions.