I have been searching about a quarter-wave flange online. But I could not find a single website about the principle of its operation. Can someone give me an idea of its operation or where I can find more information?
Flanges on wave guides are the connecting surfaces, which are secured together to assemble longer wave guides. The "quarter-wavelength" flange as a channel cut into it that is 1/4 wavelength deep. This channel serves to reduce the effects of impedance mismatches and so on. We sometime call them "stubs", name for the short lengths of open-ended conductor placed near the connectors.