Design of patch antenna with omni directional radiation pattern for wireless LAN applications

Abstract

Antennas with circularly polarization are largely used in present wireless communication systems because of their opposition to multipath distortion and polarization losses. On the other side, omnidirectional radiation patterns are mainly used since they can provide wide signal coverage and stabilize the signal transmission. As a result number of omnidirectional circularly polarized antennas have been designed and investigated over the past few years. The antenna design consist of modified ground plane connects to circular patch having two monopole modes by a set of conductive pins, to produce high impedance matching. The curved branches are designed at circumference of circular ground plane for producing a degenerate mode and producing circular polarization. The antenna prototype should be fabricated which is operating at 2.4GHz-WLAN band and measured radiation pattern, reflection coefficient, VSWR and antenna gain should well match with simulation results. In this paper simulation is done by using arlonAD320A in place of RogersRT/duroid 5880 because the cost of Rogers material is compare to arlon. But losses in arlon material are more, and these losses are reducing by decreasing number of shorting (or) conductive pins and increase the shorting pins radius. The prototype as a low profile 0.024 A a return loss value −30dB and gain of antenna is 4.68dB. To further characterize the design concept, and the antenna simulation is carried out using high frequency simulation software.