A multistrip moment method technique and its application to the post problem in a circular waveguide

A moment method technique for solving obstacle problems in a waveguide is presented. Instead of using a multifilament current representation, which leads to a slowly converging series, a multistrip representation of the current is proposed. In the procedure, the matrix elements are determined by a series involving integrals of mode functions over the strips and the convergence is improved. The true currents on obstacle surfaces are replaced by equivalent planar currents in a number of waveguide cross sections inside the obstacle. The technique is applied to a pair of metallic posts in the TE₁₁-mode circular waveguide. Numerical results are compared with experimental data