Study on complex permittivity measurements at super-high temperatures using a novel multi-functional ellipsoidal cavity/mirror

Complex permittivity measurements of microwave dielectric materials at high temperatures have always been an important research topic. In this paper, a novel ellipsoidal cavity measurement system operating in 30-40GHz frequency range is designed typically for characterizing low-loss materials at superhigh temperatures up to 1600 °C in air. This system is also applicable to high-loss material measurements by substituting the hole-coupling excitation module with horn-antenna radiators, which is then called ellipsoidal mirror measurement system. Simulation verification is carried out at room temperature and results agree well with theoretical analysis, which confirms the feasibility of the system. Experiments will be carried out later.