Design of a Mirror Stairs Multiband Microstrip Antenna Using Defected Structures

Abstract

In this article, a suggested design of mirror stairs microstrip antenna that has a planar geometry with defected structures is presented for multiband applications. The suggested antenna generates six resonance frequencies to cover 3.965 GHz (WiMAX), 7GHz, 9.188GHz (ultra-wideband, satellite)11.664GHz (space program application), 12.956GHz (indoor high-data-rate application) and 13.861 (land mobile satellite, radio navigation application) that cover the range from 2 to 17 GHz. The suggested antenna contains five rectangular slots based upon the defected ground structure (DGS) under the transmission line feed. The middle rectangular slot works as a mirror that reflects the image of the second rectangular slot. The third slot and all the rectangular slots have the same width, whereas the top side of the suggested antenna contains three rectangular strips as patch antennas based on defected microstrip structure (DMS). The suggested antenna is designed by a simulator that depends on the finite element method (FEM). The suggested antenna is printed and fabricated on double-sided substrate material that is 1.524 mm thick with an area of 45 × 40 mm2. The simulation and measurement results prove that the suggested antenna has good input impedance bandwidths as S11 ≤ -10 dB at six operating frequencies. The measurement results display good agreements with simulation results. For study purposes, we analyze the suggested antenna and simulated results compared on bandwidth, gain, efficiency, and return loss. The resultant antenna with mirror stairs shape based on DGS and DMS has improved in parameter performance mostly enhancement in bandwidth.