Frequency selective surface

The embodiment of the invention provides a frequency selective surface unit which comprises a first band-pass branch knot and a dielectric substrate used for fixing the first band-pass branch knot, the first band-pass branch knot comprises a first metal wire and two first metal patches, the two first metal patches are arranged at an interval to form a first capacitor with the physical width L, L is a positive number, and the dielectric substrate is used for fixing the first band-pass branch knot. The first metal wire is connected with the two first metal patches to form a first inductor, and the connection position of the first metal wire and the two first metal patches is located at the L/4-3L/4 position of the physical width L of the first capacitor, so that the problems of few passbands supported by a single-layer FSS and poor wide-angle filtering performance in related technologies are solved, and the effect of improving the filtering performance of the FSS is achieved. 本发明实施例提供了一种频率选择表面单元，包括：第一带通枝节和用于固定第