Abstract: The generalized S-parameter matrices of rectangular inductive irises are calculated based on a rigorous mixed method of the Mode Matching Method and the Conservation of the Complex Power Technique (CCPT). The influence of the thickness and length of the irises upon the transmission characteristic is analyzed, which includes the influence of higher order modes. Finally a seven-cavity band-pass filter of unilateral inductive irises is designed. The curve results agree well and the calculation time is greatly shortened compared with the HFSS, which verifies the validity of this technique.

Key words: conservation of complex power technique, mode matching, inductive iris, generalized S-parameter matrix