High frequency characteristics of coaxial interlaced ridge disk loaded waveguide

For the first time, the coaxial interlaced ridge-disk-loaded waveguide as slow-wave structure is presented, the software HFSS is introduced to simulate and calculate dispersion relation and coupling impedance. It is found that the change of structure parameter affects the high frequency characteristics. The results indicate that the coaxial interlaced ridge disk loaded waveguide could get a very weak dispersion and its bandwidth is better than non coaxial disk loaded waveguide. Meanwhile the coaxial interlaced ridge-disk-loaded waveguide has lower phase velocity than other coaxial structure. When it is used as the slow-wave structure of the traveling wave tube, the operating voltage decreases. Because the coaxial interlaced ridge-disk-loaded waveguide is a new all-metal structure with the advantage of high power capability and lower losses, it has a large potential application in millimeter and sub-millimeter wave traveling-wave tubes.