Design of Plasmon Absorbing Structure Suitable for Super High Frequency

Abstract

This paper proposed a plasmonic absorbing structure suitable for super high frequency. The plasmon absorbing structure is a periodic square cavity structure; the bottom of the cavity is a metal plate, the wall of the cavity is a polyester plate, and metal frames loaded with lumped resistors are printed on both sides of the polyester plate. The transmission characteristics of the absorbing structure are studied using the finite difference time domain method. The results show that the plasmon resonance characteristics can be effectively improved by loading the lumped resistance reasonably. The absorption rate of the absorbing structure is over 80% in the 4.3–21.5 GHz frequency band, and in the 4.3–7.7 GHz and 14.2–21.5 GHz frequency bands, the absorption rate is around 90%. Under different polarization modes, it is less sensitive to the incident angle. The transmission response of the absorbing structure is measured in a microwave anechoic chamber, and the measurement results agree well with the simulation results. After replacing the metal bottom plate of the absorber with a metal cavity, the radar cross-section of the cavity is reduced by 99.45% at 10 GHz. It proves that the designed and fabricated absorbing structure has the broadband absorbing ability, high angular stability, and broad application prospects.