2-DIMENSIONAL FDTD ANALYSIS OF A PULSED MICROWAVE CONFOCAL SYSTEM FORBREAST-CANCER DETECTION - FIXED-FOCUS AND ANTENNA-ARRAY SENSORS

A novel focused active microwave system is investigated for detecting tumors in the breast. In contrast to X-ray and ultrasound modalities, the method reviewed here exploits the breast-tissue physical propertie s unique to the microwave spectrum, namely, the translucent nature of normal breast tissues and the high dielectric contrast between maligna nt tumors and surrounding lesion-free normal breast tissues. The syste m uses a pulsed confocal technique and time-gating to enhance the dete ction of tumors while suppressing the effects of tissue heterogeneity and absorption. Using published data for the dielectric properties of normal breast tissues and malignant tumors, we have conducted a two-di mensional (2-D) finite-difference time-domain (FDTD) computational ele ctromagnetics analysis of the system. The FDTD simulations shelved tha t tumors as small as 2 mm in diameter could be robustly detected in th e presence of the background clutter generated by the heterogeneity of the surrounding normal tissue. Lateral spatial resolution of the tumo r location was found to be about 0.5 cm.