Applications of Microwaves to Medical Diagnostic First approach of an active microwave imaging

Only a few works have been carried out to apply microwaves to diagnostic science : such as respiratory moves, changes of respiratory moves, changes of respiratory volume, study of the move of arterial walls. Among the microwaves diagnostic methods, we must add the thermal imaging obtained from a microwave radiometer and the active imaging obtained from an interrogating wave emission. In this paper, we analyze, more particularly, the imaging active methods from the possibilities offered by the derivative radar technics that allow the detection and the localization of targets. Two methods are emphasized : the continuous monofrequency radar and the CW frequency modulating radar. We suggest to apply these techniques to medical diagnostic and we show that we can obtain a resolution factor between 5 to 10 mm for a frequency working between 1 and 4 GHz and that we can discern separated objects from a few millimeters distance.