A novel helical slow-wave structure for millimeter-wave traveling-wave tube

A novel helical slow-wave structure is proposed to develop wide-bandwidth, high-gain, high-power millimeter-wave traveling wave tube. This structure evolves from a conventional helical slow-wave structure with three parallel rectangular or other arbitrarily-shaped slots made in the outside of the helix. In this paper, the electromagnetic characteristics and thermal analysis of this structure are obtained using the finite-element-method. From our calculations, the novel and the conventional structure have similar dispersion characteristics, while the novel structure has higher heat dissipation capability than that of conventional one.