中文摘要：

为实现高强度ps脉冲电场在生物组织中的良好聚焦,仿真研究了冲激脉冲辐射天线（impulse radiatingantenna,IRA）的聚焦效果。结合前期研究成果,利用CST Microwave Studio软件建立了长椭球形IRA模型,仿真分析了其聚焦后电场在简易乳房组织模型中的传播规律。在此基础上,引入锥形天线模型,研究经锥形天线抵消主路径后IRA在生物组织中的聚焦特性。仿真结果表明：在具有低电导率的乳房组织模型中,天线在焦点处可以实现良好聚焦;当乳房组织的电导率增至0.5S/m时,其聚焦特性完全消失;引入锥形天线,当其距离生物组织边界为5cm时,可以实现IRA在较高电导率生物组织中的最优聚焦。

英文摘要：

To obtain good focus of picosecond pulsed electric fields（psPEFs） in biological tissues, we investigated the focusing effect of impulse radiating antenna（IRA} through simulations. Using previous data, we established a model of prolate spheroidalimpulse radiating antenna（pslRA） in the software CST Microwave Studio, and analyzed the propagating properties of focused psPEFs in breast tissue model. Furthermore, we introduced a conical antenna, and studied the focusing patterns of the psIRA in biological tissues while the conical antenna were neutralized the main path. The simulative results indicate that, in a breast tissue model with low conductivity, psPEFs can be well focused at the focal point of antenna, but this focusing effect totally vanishes when the conductivity of breast tissues increases to 0.5 S/re. However, optimal focusing of psPEFs in a breast tissue model with high conductivity is obtained by using a conical antenna placed 5 cm away from the edge of the tissue model.