Simplified analysis of circular microstrip patches

The author shows how useful trigonometric approximations to Bessel functions can be employed to simplify the analysis of circular microstrip patches. Specifically, it is shown how the approximations in question can be used both at the design stage and in the expressions for the radiated far field components of such patches to enable quantities of physical interest to be examined with relative ease. With respect to the design equations, a modified cavity model method of analysis is adopted and the patch is assumed to be excited in the fundamental mode by, for example, a thin coaxial probe