Optimum CAD of complex rectangular and circular waveguide circuits by combination of field theory with the nodal approach

A very fast and reliable analysis and optimization tool for complex waveguide structures is presented, wich combines the rigorous mode matching technique with nodal analysis. By this the advantages of both rigorous and fast calculation of waveguide discontinuities by mode matching, and solving of large, arbitrarily meshed circuits by nodal analysis are coupled. Together with a sophisticated gradient optimization procedure, filters, matching networks or couplers consisting of circular and rectanngular waveguides may be optimized. Mechanical tolerances and sensitivity of geometric parameters may be taken into account. The theory is veryfied by measurements.