Nevels R D, Arndt G D, Raffoul G W, Carl J R, Pacifico A
Department of Electrical Engineering, Texas A&M University, College Station 77843, USA.
IEEE Trans Biomed Eng. 1998 Jul;45(7):885-90. doi: 10.1109/10.686796.
A microwave antenna system for transcatheter ablation of cardiac tissue is investigated. A numerical model based on the finite-difference time-domain method incorporating a Gaussian pulse excitation has been constructed and frequency domain electric and magnetic fields are obtained through Fourier transformation. Results are presented for a coaxial line fed monopole catheter which is modified by the successive inclusion of a Teflon sheath outer coating, a terminating disk at the tip of the antenna, a sleeve choke, and a high dielectric constant cylinder surrounding the monopole antenna. The effects of these design features are characterized in terms of specific absorption rate (SAR) and return loss (RL). Numerical calculations are confirmed by comparing with the RL measurement of a Teflon-coated monopole containing a disk and choke.
研究了一种用于心脏组织经导管消融的微波天线系统。构建了一个基于有限差分时域方法并结合高斯脉冲激励的数值模型，通过傅里叶变换获得频域电场和磁场。给出了一种同轴馈电单极导管的结果，该导管通过依次包含聚四氟乙烯护套外涂层、天线尖端的终端盘、套筒扼流圈以及围绕单极天线的高介电常数圆柱体进行了改进。这些设计特征的效果通过比吸收率（SAR）和回波损耗（RL）来表征。通过与包含圆盘和扼流圈的聚四氟乙烯涂层单极的RL测量结果进行比较，证实了数值计算。
