ANALYSIS OF APERTURE-COUPLED MICROSTRIP-ANTENNA AND CIRCUIT STRUCTURES USING THE TRANSMISSION-LINE-MATRIX METHOD

The transmission-line-matrix method is a numerical technique for solvi ng Maxwell's equations in the presence of complex environments. In thi s paper, a general-purpose simulation program, based on the three-dime nsional symmetrical-condensed TLM model, is presented. Previous applic ations of the simulation program include the analysis of half-space an d remote-sensing problems, and calculation of the radar cross section of finite-sized conducting and material objects. In this paper, the si mulation program is applied to the characterization of aperture-couple d microstrip structures. Numerical results, pertaining to the analysis of aperture-coupled microstrip lines, offset-aperture-coupled microst rip lines, and aperture-coupled microstrip-patch antennas, indicate th e accuracy and utility of the program for analyzing aperture-coupled m icrostrip configurations. A discussion of the accuracy and efficiency of the approach is included, with limitations and possible improvement s.