fractals

Low-voltage puzzle-like fractal microelectromechanial system variable capacitor suppressing pull-in

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Amro M. Elshurafa, et al., "Low-voltage puzzle-like fractal microelectromechanial system variable capacitor suppressing pull-in" Micro & Nano Letters 7, (9), 2012, 965. Abstract: This Letter introduces an electrostatically actuated fractal MEMS variable capacitor that, by utilising the substrate, extends the tuning range (TR) beyond the theoretical limit of 1.5 as dictated by the pull-in phenomenon. The backbone concept behind the fractal varactor is to create a suspended movable plate possessing a specific fractal geometry, and to simultaneously create a bottom fixed plate complementary in

Polarization Insensitive and Transparent Frequency Selective Surface for Dual Band GSM Shielding

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Yiming Yang, et al., "Polarization Insensitive and Transparent Frequency Selective Surface for Dual Band GSM Shielding." IEEE Transactions on Antennas and Propagation, 2020 This paper proposes a single-layer, dual-band, optically transparent frequency selective surface (FSS) for GSM shielding. The design evolves from a fractal cross dipole to achieve dual band response, polarization insensitivity and wide angle of incidence stability with a miniaturized size. A two-axis symmetric structure helps to provide a stable frequency response for incident waves with different polarization angles up to