A compact semi-circular patch diversity antenna for wireless portable devices

摘要

A novel and compact multiple diversity antenna for 5.2GHz band wireless local area network(WLAN) application is designed and simulated using advanced radiation system(ADS) 2011 tool. The diversity antenna is designed by following spatial, angle and polarization diversity concepts. The diversity antenna consist of radiating patch, substrate and ground. The top conductor, radiating patch consist of 4 antenna elements which are spatially separated with a distance of less than 2.5mm and each antenna elements has an angle difference of 90 degree with both horizontal and vertical polarization with the bottom conductor, deflected ground structure(DGS) which has perfect electric property. The middle layer is the FR_4 substrate which is designed with the dielectric constant of 4.6, loss tangent of 0.01 and thickness of 1.6mm. The designed diversity antenna operates at 5.263GHz with the return loss of nearly 20dB with the bandwidth of 2GHz and isolation and decoupling of 15dB. The simulated gain and diversity at center frequency are 0.532dBi and 5.793dBi. The voltage standing wave ratio(VSWR) is 1:1.21 at 5.2GHz frequency. The radiation pattern with respect to E and H field are analyzed using the simulation tool. The antenna is suitable for wireless portable devices supporting WLAN with compact size of 30×28×1.6mm. The paper is organized in the following way. The first section consist of a brief introduction about the WLAN standards and diversity concepts are given with the literature survey. The second section consist of design procedure of the diversity antenna starting from single element design is explained and the results of the diversity antenna are discussed. The third section of the paper is finally concluded with the achieved simulated results and the future scope of the work.