An Efficient Analysis on Door Structure of a Microwave Oven Using Combined Waves of Higher Order Modes

This paper describes propagation modes of leakage waves irradiated from a microwave oven examined by using finite difference time domain(FDTD) method. In this study, the amplitude coefficient in each mode of leakage waves is calculated under the use of the amplitude level of the elctric field about these unwanted waves, and the percentage of each mode is also calculated. Furthermore, shielding effectiveness(SE) of choke structure for suppressing the leakage waves is calculated using combined waves composed of the higher order modes as each percentages. As a result, the percentage of each mode included in the leakage waves in examined quantitatively. The approximation analysis of the SE of the choke structure can also be carried out. Therefore, efficient method for analyzing the door structure of the oven has been established without the use of the memory for the calculation.