-

A narrow slot in the broad wall of a rectangular waveguide is analyzed in this work. The thickness of the wall as well as mutual effects and higher order modes are considered in the analysis. The method of moments is applied to a couple of integral equations using Green functions and appropriate boundary conditions. The tangential electric field on the upper and
lower. surfaces of the slot is therefore
obtained. Sinusoidal functions are used as basis functions for expansion of these fields along with the Galerkin method. Using
these basis functions, an accurate solution can be achieved and unlike other basis functions, a few terms are sufficient for a convergent solution. The resulting matrices are therefore reduced in dimension with less computational time. Various parameters of the slot using analytical method is obtained
and results are compared with the existing experimental data. These results show the accuracy of the method and are in close agreement with an error of about one percent.