Design Optimization of RF-MEMS Based Multiband Reconfigurable Antenna Using Response Surface Methodology

摘要

Reconfiguration of antennas, in terms of frequency response and return loss, is the most desirable feature in the world of modern wireless communication systems. This paper is dedicated to investigate the optimized characteristics of Reconfigurable Sierpinski Fractal Antenna by using Radio Frequency Micro-electromechanical Systems (RF MEMS) switches. A triangular Fractal patch antenna is designed upto fourth iteration with a 60° flare angle and self similarity with a log-periodicity of δ = 2. Four sets of RF-MEMS switches are separately designed that are used in the antenna to analyze the diversity in terms of output responses. Depending upon states of the switches; the antenna can operate in five different modes due to which a variation in output values can be observed. The antenna along with the switches is integrated on a substrate with permittivity ε_r = 2.5. A Response Surface Methodology (RSM) is a technique used to analyze the impact of various design parameters on the output responses of the antenna including resonance frequencies and return loss. A combined desirability function is used to find the optimal values of the design parameters that result in desired output response values for the antenna. The analysis is carried out from 1 to 15 GHz using Ansys Electromagnetics suit 17.2 software. Moreover, since the Seirpinski Gasket Fractal antenna has a multiband behavior, therefore it radiates at five different frequencies, while keeping the radiation patterns constant. However, operating frequency and return losses of the final model are examined in detail to analyze the reconfigurability of antenna.