Synthesis of multi-mode waveguide systems

A new method of synthesis, based on iterative improvement of waveguide wall converting fields, is suggested. It is assumed that an input (incident) field structure and an output (desirable) field structure are given at two (left and right) cross-sections. In accordance with the method an improving perturbation to surface at each iteration should be proportional the field difference of left-to-right and right-to-left conjugated solutions. This method is universal and might be applicable for calculation algorithms based on coupled mode formalism, FDTD technique, integral equation method and others. Problems of convergence, accuracy, and time expenses for computer calculations are investigated. Many components (mode converters, bends, mirror lines, etc), which were calculated and tested at low power level, are presented.