Coupled cavity traveling-wave tube with oblong cavities for increased bandwidth

摘要

A coupled cavity traveling-wave tube is disclosed wherein each interaction cavity has an oblong configuration in a plane perpendicular to the tube axis. The oblong cavities have a length-to-width ratio of a predetermined value between about 1.2 and 1.6, preferably being about 1.5. Coupling apertures in the end walls separating adjacent interaction cavities extend circumferentially about half way around aligned circular electron beam holes along the tube axis, with the circumferential extremeties of the coupling apertures lying substantially parallel to the length of the oblong interaction cavities.