A Dual Ring Interstitial Monopole Antenna with Spherical Heating Pattern for Hepatic Tumor Microwave Ablation

This paper presents a design of a coaxial interstitial monopole antenna for microwave hepatic cancer ablation. The proposed antenna is operated at 5.8 GHz to achieve a spherical shape heating pattern. The spherical shape heating pattern is desirable for curing most of the hepatic tumors. In order to adjust the impedance matching of the antenna, two conducting rings are attached to the inner conductor tip. These two rings work as a capacitive cap which enables the antenna to match at the desired frequency band with less than quarter-wavelength electrical length. The capacitive cap maintains the desired spherical heating pattern of the antenna with increasing in the heated area. The antenna is simulated using commercial COMSOL Multiphysics software. The simulation results show the good performance of the proposed antenna.