Abstract
In this article, analytical, empirical, and numerical techniques are integrated for analyzing and synthesizing circuit analog (CA) absorbers based on a single-layer frequency-selective surface (FSS). The proposed design approach dramatically reduces the number of full-wave simulations required for global optimization, so that the potential of fundamental FSS geometries can be exhaustively exploited. With the semi-analytical algorithm, the near optimal bandwidth-thickness can be quickly and reliably calculated for a given single-FSS-layer topology. To demonstrate the robustness of our semi-analytical approach, a square-patch and square-ring FSS absorbers at 10 dB level of absorption are revisited and optimized. The designs are constrained by available materials and standard tolerances for experimental validation. A manufactured prototype achieves a relative bandwidth of 144.15% and a normalized thickness of 0.0972λ L , which is superior to existing designs with more complicated FSS patterns in the literature.
Highlights
T HE PAST few decades have seen a great leap in the number of wireless communication devices, which have led to an increasingly complicated electromagnetic (EM) environment
A microwave absorber can be primarily evaluated in terms of its absorption level, relative operation bandwidth, and thickness expressed in wavelength at the lowest operation frequency
We demonstrate that the frequency-selective surface (FSS) pattern of a CA absorber does not necessarily need to be complicated, and that relatively simple shapes can achieve performance close to the theoretical limit, exploiting the fact that they are tractable for optimization
Summary
T HE PAST few decades have seen a great leap in the number of wireless communication devices, which have led to an increasingly complicated electromagnetic (EM) environment. Its bandwidth-to-thickness ratio and insensitivity to angle of incidence can be simultaneously improved by adding a dielectric cover, which serves as an impedance transformer [10], [28] Exhaustive search on such an absorber requires mn1+n2+n3 full-wave simulations in total, where m is the sample size for each design variable, and n1, n2, n3 are the number of design variables for each part of the FSS, namely the unit-cell resonator geometry, the lossless dielectrics and the sheet resistance. Assuming the sample size is m = 15 for each design variable, and the number of independent design variables for the unit-cell geometry is n1 − 1 = 1 for square patch or n1 − 1 = 2 for square ring, their reactive components can be interpolated via regression function sets (7) or (8) with m1 = 15 or m2 = 225 seed simulations respectively.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
