An L-band microwave radiometer for subsurface temperature measurement

In this paper, an L-band (1-2 GHz) microwave radiometer system prototype for subsurface temperature measurement is developed and evaluated. In combination with a microwave heating source, this system will be used for the evaluation of blood perfusion, where the temperature of the tissue is raised by the source, and the temperature decay read by this radiometer is used for evaluating the perfusion. Besides the intended application, the main novelty of this system is using two low noise amplifiers in front of the radiometer´s so-called Dicke switch in both the receiver and reference temperature input paths to improve the radiometer sensitivity. Some preliminary results of the developed system are presented. This system can potentially lead to the development of a handheld radiometric system for utilization in industry and healthcare.