A tri‐band complementary frequency selective surface with very closely spaced resonances

This paper presents a tri-band complementary frequency selective surface (CFSS) with very closely spaced bands and angular stability. The proposed CFSS element geometry is composed of double concentric rings. choice this because its good gap between resonance frequencies close, only 404 MHz from the first to second band 202 third second, which possible use CFSS. simulation performed using HFSS software design used equivalent circuit method. simulated results are compared experimental ones for validation purposes. A agreement observed measured results.