A higher order miniaturised band‐stop frequency selective surface (FSS) with angular stability performance for X‐band applications is presented in this study. The miniaturisation has been achieved by incurving the arms of conventional cross dipole shape inside. The unit cell size of FSS is diminished up to 75% compared to cross dipole FSS operating at the same resonant frequencies. Moreover, the presented FSS is designed to exhibit stable angular performance for incident angles up to about 60° for TE‐ and TM‐polarised waves. The maximum relative frequency deviation is 1.28% with respect to different angles of incidence. Although the designed FSS consists of two layers, higher order and sharp roll‐off filter characteristics have been obtained. The simulation of the proposed FSS is performed with the CST MWS. To verify the simulation results, the presented FSS is measured and a good match between the experimental and simulation results are obtained.

No abstract

A novel compact band-stop frequency selective surface (FSS) with angular and polarization stability performance for ultra-wide band (UWB) applications is presented in this paper. The designed unit cell consists of a square loop element and a crossed dipole with a ring slot element. The novel unit cell size is miniaturized to 0.047λ × 0.047λ, where λ is free-space wavelength corresponding to the lowest frequency of the UWB band. The -3dB bandwidth of the proposed FSS is between 3.05 GHz and 10.73 GHz frequencies which covers the whole UWB band as defined by FCC. Due to compact size of unit cell, the proposed FSS has good angular stability up to 60° incident angles both perpendicular (TE) and parallel (TM) polarization. The maximum resonance frequency deviation is 1.75% for TE polarization. In addition, the proposed FSS has excellent stable resonant frequency. The designed FSS is fabricated and experimental measurements are performed. There is a good consistency between numerical simulations and measurement results.

No abstract

Highlights:Graphical/Tabular Abstract  The design of single layer frequency selective surface for ultra wide band applications  To obtain angularly stable and polarization independent transmission characteristics  Compact and unit cell with small dimension designIn this paper, design of a new single layer ultra-wide band (UWB), band-stop frequency selective surface (FSS) with polarization independent and angular stability is presented. The designed FSS consists of a circleshaped conductive strip and a ring-shaped cross-dipole conductive strip. The unit cell size that forms the UWB-FSY is 0.07λ × 0.07λ, where λ is free-space wavelength corresponding to the lowest frequency of the UWB band. The -3 dB bandwidth of proposed FSS is between 3.5 GHz and 11 GHz (at normal incidence) frequencies, which covers the entire UWB band that is defined by The U.S. Federal Communications Commission (FCC). Due to compact size of unit cell, the presented UWB-FSS has good angular stability up to 60° incident angles both perpendicular (TE) and parallel (TM) polarization. The designed UWB-FSS was simulated. Afterall, simulation results was confirmed with the measurements. Figure A. Proposed unit cell and fabricated FSS layer.Purpose: A new type single-layer band-stop frequency selective surface is designed for UWB applications. Theory and Methods:In literature it is possible to find single layer FSS designs. The frequency ranges of the few existing singlelayer UWB-FSs designs do not cover the range defined by the FCC. Thus, a single layer FSS design for UWB band is important. For this purpose the resonance frequencies of the elements constituting the unit cell are set to be in the UWB band. Thereby, -3 dB bandwidth of proposed FSS is between 3.5 GHz and 11 GHz frequencies. Results:The simulated and measured results are as follows: 3 dB bandwidth of proposed FSS is between 3.5 GHz and 11 GHz (at normal incidence) frequencies, which covers the entire UWB band that is defined by The U.S. Federal Communications Commission (FCC). Also the simulated and measured results are in a good harmony. Conclusion:The small size and symmetrical structure of the unit cell of the proposed structure provided angle stability and polarization independence up to 60°. The structure was simulated by CST Microwave Studio. The transmission coefficient was measured at different angles for TE and TM polarizations and compared with the simulation results. Simulation results and measurement results are compatible with each other. Because of these properties, the designed FSS structure is a candidate for a part of UGB systems.