Dispersion Characteristics of a Helix Loaded Waveguide.

Abstract : The dispersion characteristics of a helix loaded waveguide have been experimentally investigated. Helix loaded waveguides are of interest as a slow wave structure that can be employed to increase the bandwidth of gyroton amplifiers. The structure consists of helical wires contained concentrially in a cylindrical conductor. The helical wires are close enough together to form a helical sheath justifying the assumption of azimuthal symmetry. The relevant physical parameters are the pitch angle (phi) and the ratio of the helix radius (Rh) to the conductor radius (Rc). The dispersion relations for the general azimuthal mode number are obtained for both the fast hybrid and the helix modes. Keywords include: Helix loaded waveguide, Resonant cavity, Dispersion curves, and Mode identification.