Research on tunable general FSS structure without biasing network

A novel, general tunable frequency selective surface which does not need the additional bias network is proposed. A varactor is located in the center of each unit cell. The structure is designed to make the direction of additional DC voltage parallel with the direction of polarization sensitivity, which will bring out a great tunability. Two pre-existing FSS patterns are used into this structure. Simulation results show that the structure can offer a wide tunable frequency range which is more than 23% of the initial frequency with constant bandwidth in the meantime. The generality and remoldability of the structure will make it more valuable in FSSs´ applications.