For industrial applications, microwave heating is an important technique. However, the homogenizationproblem must be taken into account to obtain rapid and reliable processes. Some industrialmicrowave heating systems are complex and expensive. In this paper, we propose a simple techniquewhich use a cavity excited by a linear or a circular electric field polarization. A better microwaveheating homogenization is obtain on ferrite and ethanol samples when the circular polarizationis used. A specific test bench was made to perform temperature measurements on several samplepoints.