DESIGN AND ANALYSIS OF WIDEBAND POLYGONAL MICROSTRIP FRACTAL PATCH ANTENNA WITH THREE DIMENSIONAL FINITE DIFFERENCE TIME DOMAIN METHOD AND UPML BOUNDARIES

A finite Difference Time Domain (FDTD) analysis of a polygonal Fractal Antenna with Uniaxial Perfectly Matched Layer (UPML) boundary conditions is presented in this paper. The software simulations are performed on the same fractal antenna using Ie3d software which works on Method of Moments (MoM). The results from FDTD simulations and ie3d nearly matches. Impact of the fractal antenna on bandwidth improvement is observed and analysed. A parametric study is performed to locate the optimum feed point for Ultra-Wideband (UWB) operation. and bandwidth enhancement is observed ranging from 2.2 GHz to 9.8 GHz making it suitable for UWB Applications the comparative study is performed by taking the bandwidth gain and volume of the antenna. The problem in implementing the geometry in FDTD involving sloped edges leading to the error due to staircase approximation is also discussed. The efficiency of the antenna is between 80% to 90% in the entire band. The gain of the antenna in the final iteration is increased up to 6 dB, Axial ratio is below 1.2dB and the directivity is above 6.5 dB.