A Dual Tuned Complementary Structure Frequency Selective Surface for WLAN Applications

A single substrate layer double metallic plane frequency selective surface (FSS) is designed with miniaturized electrical elements and two tunable pass-bands enabling Wireless Local Area Network applications. Each FSS periodic cell consists of a metallic square loop on the top metal layer and its complementary etched on the bottom metal layer separated by a thin dielectric layer. This designed FSS provides two tunable transmission bands. For predicting the frequency selective characteristics of the designed FSS an equivalent electric circuit model is also presented. To satisfy the needed requirements for Wireless Local Area Network (WLAN) applications the designed structure is optimized. Due to symmetrical nature of the design, the FSS is insensitive to variations of RF incidence angle for 90° (degree) rotations of the FSS. Simulated theoretical investigations are done by Ansoft Designer® software. Experimental investigation is performed using standard microwave test bench.