Development and Performance Enhancement of MEMS Helix Antenna for THz Applications using 3D HFSS-based Efficient Electromagnetic Optimization

Abstract

Interest of Micro-Electromechanical System (MEMS) Keywords: micro-electromechanical systems (MEMS), THz bands, helix antennas, 3D-HFSS, electromagnetic optimization.Copyright © 2018 Universitas Ahmad Dahlan. All rights reserved. IntroductionAs new applications for the electromagnetic THz field begin to emerge, a new generation of efficient MEMS antennas [1] is developed to meet the specific requirements of these high frequency systems. Many new processes of MEMS technology are just beginning to stimulate interest in this unique spectral and continue to help manufacturing THz antennas, improving their performance and achieving micro-level precision [2]. Focused Ion Beam (FIB) is one of the important processes used for fabricating MEMS antennas, especially helical antennas [3] by implementing silicon wafers that represent a very good solution to enhance the antenna's radiation and performance. MEMS helix antennas employing silicon substrates, have achieved over the past few years interesting characteristics including compact size, high directional gain, and wide bandwidth, thus their implementation into planar forms seems to become easier due to the advanced micromachining techniques [4]. This has provided a new class of THz antennas with numerous wireless access applications thanks to the use of complex simulation tools to bring the CAD for such high frequency structures to its current state of the art. Accordingly, HFSS-based Q-N and SNLP approaches lead to excellent optimization solutions carrying out by replacing repeated electromagnetic simulations whilst still retaining a good accuracy as compared with finite element modeling to improve the accuracy of the existing design models or develop new design models. This procedure requires acceptable simulation time especially for defining the problem that needs reliable and fully functional approximations. This paper proposes for the THz frequency access systems a compact geometrical configuration of a wide MEMS Helix antenna using HFSS software. The MEMS antenna geometry is optimized using both Quasi-Newton and Sequential Non Linear Programming algorithms to offer fitness functions for excellent bandwidth learning and fast configuration evaluating. The antenna occupies a very compact volume of 79×80×152 um (0.960 10-3 mm3) including the silicon substrate having a thickness of 9.3 um and a dielectric constant of 11.9.

Controlling The Radiation Pattern of Patch Antenna Using Switchable EBG

“…Such microstrip antennas have an inherent problem of surface wave excitation. The mushroom-like EBG surface as describe in [1] and other description of the uni-planar EBG surface is shown in [2] was utilized for surrounding a microstrip patch antenna to reduce the impact of the surface waves and an improvement in the performance of antenna [3][4][5][6][7][8][9][10][11]. An important property of surface wave suppression supports to develop performance of antenna, like enhancing the gain of the antenna [12,13], decreasing the back radiations [14] and reduction in antenna size [15].…”