Coupling and Footprint Numerical Features for a Bow-tie Antenna Array

Abstract

For use in the detection of breast tumors, in previous works we numerically designed an array of four bow-tie antennas. Its suitability in terms of performance has been confirmed. Now we are interested in improving the precision of the whole detection process and to extend it to more realistic breast-tumor models including the natural inhomogeneity of breast tissues. Therefore, in this work the breast-tumor model is non homogeneous besides to be a dispersive model.An important part of this process depends on the array. Here we analyse the characteristics of the isolation between antennas and the footprint at a middle distance in the region illuminated by the array. We determined the scattering matrix of the array and its footprint in different situations observing a lower coupling between the elements when the separation between the antennas was decreased and that the footprint was of smaller dimensions.With simultaneous excitation of the antennas and by varying the phases by 180° it was possible to expand the scan zone of the array.We present some tumor location results in terms of the absorbed density of energy to show the procedure performance and also by applying microwave confocal techniques.The numerical technique employed throughout the process was the Finite-Differences Time-Domain (FDTD) method.