A Miniaturized Frequency Selective Rasorber with High Frequency Harmonic Suppression

Abstract

A frequency selective absorber for harmonic absorption (HA-FSR) is proposed in this paper. It consists of a miniaturized frequency selective surface (FSS) for harmonic suppression and a circuit analog absorber (CAA) for harmonic absorption. The frequency selective rasorber (FSR) unit is 6.7 mm × 6.7 mm (0.129λ × 0.129λ, where λ is the free space wavelength of 5.8 GHz). The simulation and measurement show that the HA-FSR can generate a transmission band from 4.51 GHz to 7.47 GHz and a −10 dB absorption band from 11.96 GHz to 22.31 GHz, which covers more than 3 times of the main passband harmonic band. In addition, the FSR has good polarization stability and angle stability within 30 • of oblique incidences under both TE and TM polarizations, which can be applied to electromagnetic interference shielding field and low-observable platforms.