Three-dimensional frequency selective surface design for x-band

Periodic structures, which are frequently encountered in nature, have attracted the attention of many researchers and have been the starting point for applications developed in different fields. Structures created by repetition of a unit cell over a period of time have been studied by many researchers in the electromagnetic field since the early 1990s. Frequency Selective Surfaces (FSY), which are formed by periodic assembly of different unit cells in the form of metallic patches on openings on a thin conductive layer, can be defined as electromagnetic filters with low-pass, high-pass, band-pass or band stop characteristics for certain frequencies. The unit cell geometry used in the design of the FSY and array of this may be arranged to provide for the reflection or transmission of the incoming electromagnetic wave. FSY's have recently been widely used in the fields of wireless communications, microwave and radar systems. Relatively recent three dimensional (3D) structures compared to conventional two dimensional (2D) FSYs have the potential to provide improvements for problems encountered in 2D structures and provide more flexibility in controlling frequency response than 2D construction. In this study, a 2D FSY design with three different geometry conductors containing cylindrical, octagonal and square, is designed for 10 GHz, which is the X band center frequency, and then three new 3D FSY structures are proposed, which are achieved by increasing the conductor height. The effect of conductor height change is investigated and the results are analyzed by analyzing the unit cell parameters for the 3D FSYs with the electromagnetic simulation program Computer Simulation Technology (CST) Microwave Studio Suite. The designed 3D FSY's ara seen periodically band-stop and band-pass filter characteristics of the structures with increasing height of the conductive rings in the unit cell. In parameter analysis, the increase in unit cell parameters outside the conductor height reduces the resonance frequency. In the TE mode, the resonance frequency increases and the band width decreases with the angle of incidence. In the TM mode, the frequency response is stable and the band width increases with the angle of incidence.