STEPPED TRANSMISSION-LINE MICROWAVE FILTERS AND TRANSFORMERS WITH IMPROVED PARAMETERS

摘要

The article presents design method of stepped transmission-line microwave fillers and transformers with improved parameters. In many situations microwave filters and transformers designed by conventional methods (without discontinuity influence on frequency characteristics taken into account) have not acceptable characteristics. Discrepancy between ideal and measured characteristics increases with frequency because of to large Z_(max) /Z_(min) ratio (e.g. d_(max)/d_(min) for coaxial line) and large dimensions in comparison to wavelength λ. Significant improvement of discussed networks parameters can be accomplished by using optimisation procedures and taking adequate discontinuity model into account. As a result we obtain filters and transformers with very well convergent theoretical and measured characteristics.