Field characteristics in dielectric rectangular wave guide with harmonics

In this paper field distribution inside rectangular dielectric waveguide has been studied assuming square wave field incidence for its dominant and other modes. Incident square wave field can be seen as made up of various harmonics of sine and cosine functions. Here up to five harmonics of sine and cosine function are taken to represent the field distribution and mathematical equations are derived. Field distribution inside and outside the wave guide are plotted using Mat Lab application for even and odd symmetric fields. Two modes, E_mn^y and E_mn^x of propagation are considered inside the dielectric wave guide, having most of the electric field in y direction and x direction respectively. From these, Eigen equations and propagation constant can be calculated for harmonics of the incidence wave function. For frequencies above cut-off, field is assumed to be confined inside the waveguide and decaying exponentially outside, as assumed in Marcatili´s method to find the wave guide solution.