Comparison of subdomain functions in the moment method for quasiperiodic waveguiding structures

Phenomena of coupling of wave paraxial beam and quasisurface wave at perfectly conducting plane with segment of spatially oscillating surface impedance is considered. Integral equation for perturbed current distribution is obtained. Method of moments is used. Solution was expanded in terms of subdomain basis functions. Various types of subdomain functions are compared in form of a combination of atomic function and the Lagrangian interpolating polynomials. Advantages of subdomain functions of higher order were demonstrated.