Plasma as a conductive medium for traveling-wave antenna

It is shown that the surface waves of the current propagation in a column of cold isotropic plasma are the source of the paraxial electromagnetic radiation. The influence of the dielectric tube waveguide surrounding the plasma on the dispersion properties of the plasma column is investigated. The corresponding dispersion equation is derived and solved numerically. The plasma and dielectric waveguide parameters are determined, at which the travelling surface wave deceleration is close to unity.