A way to design the miniaturized dual-stopbands FSS based on the topology structure

Abstract

The miniaturized frequency selective surface (FSS) obtained by connecting a number of limbs with two flexible adjustable transmission zeros is proposed in this paper. The proposed FSS has two transmission zeros on both sides of the passband. The effects of the geometrical parameters on the bandwidth of transmission zeros and pole are analyzed. Adjusting the numbers of the limbs in the FSS can make a great difference to the ratio of the frequencies of the two working transmission zeros, and the coupling between the adjacent FSS unit cells is used to adjust the ratio of the frequencies of the two working transmission zeros slightly. The simulated results show that the ratio of the frequencies of the two working transmission zeros has wide adjustable range. The effects of the ways to connect the limbs on the ratio of the frequencies of the two working transmission zeros are analyzed. The prototype of the FSS with two limbs is fabricated and tested to verify the feasibility of the proposed method. The measured results show that the FSS designed by the proposed method has good polarization and angel stabilities, and this proves the proposed way is effective. This FSS is a good candidate to isolate the communication systems with two working bands.