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Abstract

A small patch antenna is associated with passive (reactively loaded) elements (varactors) in order to auto adjust the resonant frequency in a single-channel multi-frequency configuration appropriate for biomedical applications. As a supplementary study of the authors in the field of detection of temperature abnormalities in human tissue phantom using microwave radiometry, this paper adds a contribution to frequency readjustment when a shift occur due to the fact that the human body is a complex and stratified dielectric object. The optimization of the array is performed using a Genetic Algorithm (GA) tool as a method of choice. The adjustment in the measurement frequency is performed by altering the values of the passive elements according to the shift needed.

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Dr. Christos D. Nikolopoulos

Mr. Anargyros T. Baklezos

Professor Christos N. Capsalis