The wideband characteristics of monopole antenna with parasitic non-uniform wire rings

In this paper, antenna with parasitic non-uniform wire rings is studied. The return loss of the proposed antenna and conventional monopole antennas is investigated using the simulation package CST MW Studio ver. 3.2. The comparison between the results of the simulation and the data in literatures is carried out. The effects of the wire rings on the reflection coefficients of the proposed monopole antenna are described. The case of the non-uniform wire rings employing the weighting function to the simple monopole is dealt. The simulated results of the antenna are obtained for various values of the radius of wire rings, the number of rings, and the period of each wire