The Modeling Techniques for Analyses of Electromagnetic Distributions and Reflection Coefficients for Microwave Ablation

摘要

many advantages of microwave ablation over the other ablative therapies in the field of liver tumor ablation have driven researchers to develop innovative interstitial microwave antennas to effectively treat deep seated, nonre-scctable hepatic tumors. A new coaxial antenna for microwave ablation therapies has been proposed in this research paper. Three dimensional Finite Element Method (FEM) has been used to design the results of the proposed antenna. Objective metrics for assessing the characteristics of helix antennas for microwave ablation by analyzing the electromagnetic field distributions and reflection coefficients for efficiency of antenna has been specified and verified for the proposed antenna, at frequency of 2.45GHz. Our simulation results, Relative permittivity at 2.45 GHz during thermal ablation. Accumulated ablation times noted on each figure to identify temporal variations. Values tended to drop quickly in all cases when temperatures reached 100 °C and continued to drop as temperature was maintained and the tissue became more dehydrated. Changes were irreversible as tissue returned to baseline temperatures. We designs the antenna matching obtained at 2.45 GHz. During thermal ablation, the reflection coefficients it can be noted that the antenna resonance shifts toward higher frequencies and the electric field distribution at the near field region changing follow the temperature variations in tumor tissue.