陣列天線微波熱療系統-初步設計與測試

Abstract

陣列天線微波熱療系統主要應用於表面上或人體內部腫瘤的治療，其基本 原理乃是利用腫瘤細胞對微波輻射的吸收特性，使細胞組織的溫度升高， 進而使細胞壞死。本論文中，首先進行在915MHz下，單根絕緣偶極天線對 鹽水加熱特性測試，接下來構裝一套相位/輸出功率可調的四根天線陣列 微波加熱系統，並測試此系統對鹽水加熱後的熱吸收場型分布。最後並靜 態測試以一"漸近搜尋"適應性控制法則來達到特定的熱吸收場型分佈。 Interstitial microwave antenna-array hyperthermia system for the treatment of superficial and deep-seated tumors has been investigated in recent years. A critical parameter in the hyperthermia system is the SAR (specific absorption rate) pattern, which gives information about the energy absorption in the tumor and surrounding tissue. In this thesis, we first present the SAR distribution produced by a simple Insulated Dipole Antenna (IDA), and then the Ez-field pattern of the IDA measured using an E-field probe. Finally we construct a phase and power level adjustable four-channel hyperthermia system operating at 915 MHz. In addition, a gradient-search adaptive control algorithm for shifting hot spot or null spot to any point is developed. Some static testing of optimal SAR pattern by applying the algorithm is performed.