UWB-Printed Rectangular-Based Monopole Antenna for Biological Tissue Analysis

This paper presents the design of a printed step-type monopole antenna for biological tissue analysis and medical imaging applications in the microwave frequency range. The design starts from a very simple and widely known rectangular monopole antenna, and different modifications to the antenna geometry are made in order to increase the bandwidth. The antenna dimensions are optimized by means of a parametric analysis of each dimension using a 3-D electromagnetic simulator based on the finite element method. The optimized antenna, with final dimensions of 40 36 mm2, is manufactured onto a low-cost FR4 (fiber glass epoxy) substrate. The characteristics of the antenna have been measured inside an anechoic chamber, obtaining an omnidirectional radiation pattern and a working frequency range between 2.7 GHz and 11.4 GHz, which covers the UWB frequencies and enables the use of the antenna in medical imaging applications. Finally, the behaviour of four of these antennas located around a realistic breast model, made with biocompatible materials, has been analysed with the electromagnetic simulator, obtaining good results and demonstrating the usefulness of the designed antenna in the proposed application