Microwave Filters Utilizing the Cutoff Effect

Two band-rejection microwave filters employing the waveguide cutoff effect are discussed. One type utilizes the cutoff property in the series arm of an E plane tee to improve the filter's characteristics, while the other utilizes this property in the E and H arms of a magic tee. Experimental data for both single and multistage filters are presented. Methods of obtaining low standing wave ratios over a broad pass-band are also presented.