Broadband analysis of finite microstrip patch antenna structure using FDTD

Broadband analysis of a microstrip patch antenna on a finite substrate is investigated using the finite difference time domain (FDTD) method. The effects of varying the ground and dielectric size against the return loss at the input port and the far fields are discussed. Two different ways of feeding the antenna are addressed. The problem space size requirements of the FDTD method are presented. A thin wire code that includes the wire radius of the coaxial feed cable is used. The frequency response of several microstrip patch antennas is analysed over wide bandwidths, using Gaussian pulses with a total bandwidth of 20 GHz. The results are in good agreement with measurements.