A new method

mode matching

is presented for the analysis of monopole antennas on a circular disk.This approach is facilitated by placing two parallel PEC grounds above and below the antenna and dividing the space into several subregions reasonably

thus allowing use of cylindrical harmonic expansions in each subregion.Then expansion coefficients are found by enforcing the PEC boundary condition and continuity condition at the regional boundary surface.The current and input impedance of monopole antennas on disk is computed based on the above calculation.For monopole antennas with different circular disc in radius

this method can lead to very good agreements between the theoretical results and the experimental results available in literatures.In addition

this method is efficient since the fields are expressed in closed form.