A triple Bandpass Frequency selective surface for enhancement in the transmission of WiMax and WLAN application

While we are moving towards a digitized era where everything is getting digital, then the transmission of the signal at the desired frequency range becomes a matter of apprehension. Signal transmission has affected by various propagation effects, path loss, interference etc. As is well acknowledged that Frequency selective surface is a filter which has a stable frequency response even though the electromagnetic waves to surface are fluctuated. A Bandpass FSS is proposed in this paper that has stable frequency response as the proposed structure symmetrical and insensitive towards polarization. The proposed structure contains a single sided FR4 substrate with dielectric constant 4.4mm, thickness 1.6mm tangential loss 0.025 and the dimension of the unit cell is 0.24 λ × 0.24λ. The structure consists of a square and two octagons that provide stable frequency response at 2.4GHz, 3.5GHz, and 5.5GHz. The simulated results shows good insertion loss in both TM and TE wave modes at various angles of incidence. Simulation is carried out in CST microwave studio that is based on FDTD method in frequency domain solver.