Design of L-band Energy-Selective Surface with Circular Ring Gap

An narrow-band energy-selective surface (ESS) in L-band is presented for airborne GPS antenna protection. Periodic square metal inlaid with circular ring gap is designed and loaded with pin diodes to obtain the energy selection characteristics. the parameters of unit structure are determined with optimization. By simulation, we know that the insertion loss is less than 3dB and the shielding efficiency is more than 30dB. Using the method of equivalent test, we experimentation verified that the proposed ESS structure can be used for airborne GPS antenna protection