FDTD simulation of a microstrip phased array with a coaxial feed

In the paper, the authors present a novel approach for analysing microstrip patch antennas using the finite difference time domain (FDTD) technique. Specific attention is paid to the issue of modelling the coaxial feed line, using a voltage source with a lumped resistance type of internal impedance. The results of the simulation are found to be in close agreement with those derived by using the method of moments (MoM). The analysis is then extended to the case of planar arrays of microstrip patch antennas. The active element pattern of the patch antenna is first extracted by using the FDTD, which is later used to predict the performance of the planar array. The paper also examines the numerical superefficiency and accuracy of the technique, and discusses its computational complexity.