Investigation of Circular Patch Metasurface (MS) on Inverted Suspended Circular Polarized Antenna

Abstract

In this paper, an analysis of different stage of circle patch metasurface (MS) on basic structure of inverted suspended circular patch with square slot antenna design is proposed to investigate its effect toward the basic antenna performance. The basic antenna was designed based on inverted suspended circular patch with air gap separation between the patch substrate and copper ground plane at a distance of 10 mm (Basic design). Then, different design of MS structure (Design A, B, C & D) consisting of 5 x 5 unit cell of homogeneous periodic element is place in between the air gap of the basic antenna. All of MS design is located at a fixed position to study the effect of different MS shape to the Basic antenna performance. The proposed antenna and MS structure had been designed and simulated by using Computer Simulation Technology (CST) Software. Target application for this antenna design is for Wireless Local Area Network (WLAN) at operating frequency of 2.4 GHz. Simulation performances in term of return loss, resonant frequency, bandwidth, realized gain, directivity, axial ratio, total efficiency and radiation pattern at the design frequency are investigated and discussed. From observation on simulation result, resonant frequency of Basic design is shifting to a lower frequency from 2.4 GHz to 2.19 GHz (Design C and D) with the integration of the MS structure. Design C obtained the widest axial ratio bandwidth among all of other design with 1380 MHz covered from 1.31 GHz to 2.69 GHz. Directivity for Basic designs at 2.4 GHz increases from 7.94 dBi to 8.17 dBi, 8.16 dBi, 8.15 dBi and 8.06 dBi (Design A, B, C and D) respectively.