Broad-Band Matching with a Directional Coupler

This paper presents the results of a theoretical and experimental study of a waveguide matching technique which allows a directional coupler to be located any distance away from the discontinuity causing the original mismatch and a broad-band match to still be obtained. Design curves are included which give the required coupling coefficient of the directional coupler and the power loss for a given initial mismatch and desired vswr reduction. Experimental confirmation of the theory is also presented.