Thermal management of transmission-absorption rasorbers

Transmission-absorption (T-A) frequency selective rasorbers (FSRs) play an important role for stealth aircraft radomes. However, with growing radiated power from antenna systems, thermal effects of T-A type FSRs can no longer be neglected. This paper presents thermal management of T-A type FSRs for the first time. We proposed a novel folded square ring FSR composed of resistance films, which features a -1 dB transmission bandwidth from 1.74 to 2.11 GHz, and a -10 dB reflection reduction bandwidth from 6.71 to 16.92 GHz. Compared with conventional resistor-loaded metallic FSRs, our proposal achieves an 87.4°C peak temperature drop, when irradiated under 2 GHz with an incident power density of 20 kW/m 2 . The absorption layer determines the maximum temperature of the T-A type FSR, which highlights that carefully designing this layer is critical for thermal regulation. Excellent agreement of experimental and numerical data validates the feasibility of the presented design methodology.