Study of Temperature Distribution of an One Layer EM-wave Absorber Using a Lossy Magnetic Material under High Power Injection

Utilization of electromagnetic absorbers under high power is increasing, for estimation of performance of high power radars in anechoic chambers. Variation of the absorption characteristics of the absorbers under the condition is expected, due to the generation of heat or temperature change. Absorbers using lossy magnetic materials are used widely because the absorbers are typically thin, compared with absorbers made from lossy dielectric materials. If the absorbing layer is thin, it is considered that the temperature rise is higher because the heat capacity is small. Therefore, to know the temperature distribution of absorbers using lossy magnetic materials under high power injection is important. In this paper, the temperature distribution of a EM-Wave absorber using a lossy magnetic material is calculated by a coupled analysis method we proposed for electromagnetics and all the heat transmissions. The computed result is compared with the measured result. Finally, the calculated and measured results are compared and discussed.