Triple band frequency selective surface design for global system for mobile communication systems

Abstract

As a result of the enormous increase in mobile phone usage throughout the world, mobile phone base stations are located in almost everywhere nowadays. Many scientific studies have investigated possible health symptoms of mobile systems radiation. The globally recognised organisations have started to release maximum radio‐frequency (RF) exposure levels that are regarded as safe. An efficient approach to decrease the RF exposure levels inside the buildings is to transform building walls to a frequency selective surface which filters out global system for mobile communication signals but allows the others, such as radio and television signals. This study proposes a new frequency selective surface element geometry which leads to a minimum 20 dB attenuation in 900, 1800 and 2100 MHz mobile communication bands according to Swiss electromagnetic radiation prevention limit values (NISV, 23 December 1990). High‐frequency structure simulator software is used for simulation and design purposes. Due to a given good insight into the resonance characteristics of the FSS structures, it is benefited from the equivalent circuit model in the optimisation process. Achieved results show that the proposed FSS element geometry has a stable frequency response with minimum 20 dB of attenuation levels for transverse‐electric (TE) and transverse‐magnetic (TM) polarisations when the angle of incident wave is varied from 0° to 60°.

Design of Compact Polarization Insensitive Triple Bandstop Frequency Selective Surface with High Stability under Oblique Incidence

“…In order to comprehend the novelty of the proposed structure, it is compared with previously reported bandstop FSS [8][9][10][11][12][13][14][15][16] and the results are tabulated in Tab. 2.…”

“…The table highlights that for dual bandstop FSS [9][10][11], maximum stability under oblique incidence is provided by [9] up to ±75°. However, when bandstop resonances increase to three, the maximum stability under oblique incidence is reduced to ±60° [13], [16]. Hence, triple bandstop FSS will fail to act as bandstop filter where they are exposed to complex multipath environment when incident electromagnetic wave may frequently approach ±90°.…”

“…In order to satisfy these requirements, multiple bandstop FSS with polarization insensitivity and stability under oblique incidence are seeking attention and have been reported in recent literature [9][10][11][12][13][14][15][16]. However, for FSS structures acting as multiple bandstop filter (BSF), the response under oblique incidence gets worse as it approaches towards grazing angle of ± 90°.…”

“…However, for FSS structures acting as multiple bandstop filter (BSF), the response under oblique incidence gets worse as it approaches towards grazing angle of ± 90°. Hence, stable characteristic is limited to, generally, within ± 60° incident angle in case of triple band FSS [12][13][14][15][16]. As a result, the use of multiband bandstop FSS becomes limited in complex multipath environment.…”

A Novel Quasi-Tem Mode Planar Waveguide for Periodic Structure Measurement Applications

“…With the rising of metamaterial, amounts of researchers pay their attentions to metamaterial due to its peculiar properties such as single or double negative index [1,2], zero refraction index [3], and gradient refraction index [4]. Taking the advantage of metamaterial, some amazing products, such as cloaking [5], perfect absorbers [6], frequency select surfaces [7][8][9], are produced. In general, some experimental works are carried out to verify performances of designed metamaterial structures, such as resonant frequency and transmission characteristics.…”