Patch Antenna Modeling Issues Using Commercial Software

The method of moments, implemented in 2.5-D for multilayer antenna structures, or implemented as a fully 3-D solution of Maxwell´s equations, is a popular method for microwave antenna simulations. Commercial software was used to simulate an aperture-coupled patch and a pin-fed patch antenna element. The simulation results are compared with experimental data measured for antenna prototypes having finite substrate and ground plane dimensions. The aperture coupled patch has microstrip feed line extending to the edge of the substrate where a coaxial connector is installed between the microstrip and ground plane. The pin- fed patch has coaxial connector feed with finite size ground plane and radome without dielectric substrates. A 3-D simulation is used to capture the effect of a finite ground plane compared to a 2.5-D model. The calculated and measured antenna performance are compared indicating that the 2.5-D simulations are sufficient for the design of conventional patch antennas but detailed analysis or novel designs may require a fully 3-D model.