Trigonometric-series model of star junction consisting of H-plane coupled rectangular waveguides

An effective electromagnetic model is presented for the symmetrical H-plane junction of N rectangular waveguides. In the central cavity and waveguide arms, the field sought is expressed in the form of simple trigonometric-series expansions which are constructed using the domain-product technique and the symmetry properties of the structure. That gives a chance to perform analytically all mathematical manipulations before solving the final system of algebraic equations. The validity and efficiency of the solution are proved by the convergence tests as well as by comparison of the data obtained with the known ones. The approach is applied to the scattering characteristics of the unit. The obtained frequency dependencies of S-matrices are presented for N = 3 to N = 7.