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Description

Nowadays, more no of electronic devices are invented due to rapidly growing technology. This huge number of electronic devices creates two major problems. One is electromagnetic pollution and the other one is radiating emission. Due to the emission of electromagnetic interference (EMI) from numerous electronic devices, the amount of electromagnetic pollution is growing continuously. There are many techniques to address the above issues and one among them is called “Frequency Selective Surfaces (FSS)”. These challenges where addressed in the three modules of the research work. Module 1 focused on structural based FSS design. There are two designs in this chapter that differ in the number of layers. In first design, a polarization insensitive dual band FSS for S band and X band applications are designed based on single layer structure. It provides dual stop bands at S-band (2.64 GHz) and X-band (8.3 GHz) by using 0.098λ0 unit cell size with the angular stability 60֯ and also obtained maximum SE value of 47.20 dB at 2.6 GHz and 45.7 dB at 8.3 GHz. Next, a dual layer structure based ultra-wide band (UWB) FSS is created for Ku band space shuttle applications. Here the unit cell is formed by combining circular loop (CL) on top layer and miniaturized square loop (MSL) on bottom layer with the unit cell size is 0.263λ0, it provides ultra-wide bandwidth ranges from 11.76GHz to 20.93GHz. therefore, the fractional bandwidth is 9.17GHz with 60֯ angular stability. Module 2 concentrated for X and Ku band applications by using 2.5D frequency selective surface structure. This module design produced maximum fractional bandwidth of 96.7% from 6.26GHz to 18GHz with insertion loss of 0.11 λ. Its unit cell size 0.11λ, and its performance in terms of angular stability and shielding effectiveness are main advantages of this FSS. In this design obtained maximum shielding efficiency value of 51.07dB over the X and Ku band with stable performance up to 60֯incidence angle. Finally discusses on application based FSS designs, especially this research focuses to design polarizers used in both transmitter as well as receiver side.