Broadband omnidirectional circular patch antenna

Abstract

This paper presents an omnidirectional microstrip circular patch antenna with conical radiation pattern. Geometric parameters of the antenna such as metal disk radius, thickness and permittivity of the substrate have been selected on the basis of theoretical predictions. It has allowed us to provide a desirable resonant TM/sub 01/ mode excitation. The results have shown that the antenna of this kind with VSWR/spl les/2 and bandwidth of 18% has a conical radiation pattern oriented 36/spl deg/ to the zenith. The antenna also has a level of side radiation as well as a cross-component level less than -25 dB. The radiation pattern width and the direction of maximum radiation change within the working frequency band of 17% and 40%, respectively. This antenna can be successfully applied for mobile system, wireless indoor communications, etc.