Temperature Measurement by Microwave Radiometry

Temperature is an important parameter in the industrial world. For example, temperature control is of a greater concern in food processing industry for safety reasons as well as for product quality. Recently, microwave processing of powder metallurgical bodies has been shown to be very promising. Fully dense bodies with improved mechanical properties could be produced due to finer grain size. In the field of the sintering of materials, a control of the temperature inside heated parts is necessary to avoid local melting or distortions. The medical field is another sector particularly interested in non invasive techniques for the measurement of human temperature. In fact, the corporal temperature is proved to be a pertinent parameter in the scope of diagnosis, monitoring of many pathologies and for the posology of some medicines. None of the current methods for measuring temperature (thermocouples, optic fibers, infrared, etc...) give by a non-invasive way continuous temperature information. So, microwave radiometry brings a neat solution to measure and control non-invasively temperature inside a dissipative material. This paper is concerning the design and the realization of specific radiometric sensors in order to measure and control temperatures from a non-invasive way by microwave radiometry either in industrial or in medical applications.