Design and Evaluation of High Gain Microstrip Patch Antenna Using Double Layer with Air Gap

Wireless technology is one of the main areas of research in the world of communication and a study of communication system is incomplete without understanding the operation of an antenna. Recent trends of wireless mobile communication technology are towards the miniaturization and demand for more robust and compact designs. This paper proposed a low cost, efficient, high gain and wideband Microstrip Antenna (MSA) using rectangular patch for wireless applications. In this paper an attempt is made to optimise and fabricate a double layer RMSA with air gap to obtain a high gain antenna operating over a 2.4-2.483 GHz ISM band. It consist of double sided copper ensure using one side as ground plane and other side as feed network. By inserting an air gap between radiating and ground planes. The air gap reduces both the electric field concentration on the lossy epoxy and the effective dielectric constant of the radiating plane. This structure is low cost, easy for fabrication and FR4 is used which is easily available substrate with permittivity 4.4, height 1.59 mm and loss tangent of 0.02. The structure is optimised using Zeland IE3D version 14.10. The optimised MSA provides a maximum gain of about 8.6 dBi with less than 1dBi gain variation over the operating frequency band, RL< 9.5 dB, VSWR < 2, SLL < 16dB, front to back ratio > 18 dB and efficiency > 75% . The close similarity between simulation results and fabricated results has been observed.