An L-band narrowband energy selective surface design

The Electromagnetic Energy Selective Surface (ESS) is a concept proposed by the Reference Frequency Selective Surface (FSS). The basic idea is that "the energy of the electromagnetic wave can pass smoothly when it is less than the safety threshold, and it is automatically shielded when it is greater than the safety threshold". The adaptive switching characteristic can effectively protect the strong electromagnetic pulse without affecting the normal operation of the equipment. At present, the design of ESS rarely has a narrow band and the shielding performance is greater than 30dB. In this paper, a narrow-band ESS operating in L-band is designed. The results of CST show that the working frequency band of the structure is between 1.426GHz and 1.623GHz, which covers the working frequency range of the airborne GPS antenna 1.5~1.57GHz. The insertion loss is less than 3dB when it is in the wave-transparent state, and the shielding efficiency is more than 30dB when it is in the shielding state. It can be used for high-power microwave protection of the airborne GPS antenna.