Active microwave arrays for medical hyperthermia: Device selection, characterization and implementation of their drive circuits

Abstract

Significant progress toward a functional 73 element, 730 watt, active microwave phased array has been made. This array, designed for medical hyperthermia applications, has significant size restrictions leading to a novel space conscious design. Unlike other hyperthermia devices, each array element is designed to have full 360° phase control with better than 1° resolution. Full amplitude control, with 10 bit amplitude resolution is implemented. The array is designed to operate in the 2.45 GHz ISM band. Measured operational data is presented and is compared to simulations performed with Compact Software's Microwave Harmonica®. A sophisticated control system for the array has been designed, built and tested. The system provides 160 computer controlled 10 bit analog control lines to drive the array. Sampling of various system parameters is made possible through the use of a 96 channel, 12 bit analog to digital converter system. This system provides 4 mV resolution and a 440 Hz sampling rate for each of the 96 measurement channels.