Frequency selective surface structure

A frequency selective surface structure, comprising:

• a substrate;
• and
• at least one conductive layer, disposed on the substrate and comprising four central double-frequency patches, wherein the four central double-frequency patches are spaced apart from one another and are arranged in a 2×2 array;
• wherein, in each of the four central double-frequency patches, the central double-frequency patch is in a polygonal shape and has a central corner part, a plurality of outer corner parts and a plurality of notches, the central corner part is located closer to a geometric center of the at least one conductive layer than the plurality of outer corner parts, and the plurality of notches are located on the plurality of outer corner parts, respectively;
• wherein the at least one conductive layer further comprises a high-frequency patch, the substrate has an outer surface, the at least one conductive layer is disposed on the outer surface, the outer surface is in a polygonal shape and has a plurality of substrate corner parts, the high-frequency patch comprises a peripheral part and a plurality of protruding parts, the plurality of protruding parts protrude inwards from the peripheral part, the peripheral part is located on an outer edge of the outer surface and surrounds the plurality of protruding parts and the four central double-frequency patches, and the plurality of protruding parts are located on the plurality of substrate corner parts, respectively.