Properties of dielectric-tube waveguides

Two aspects of dielectric-tube waveguide properties are considered. First, a mode designation is given which is consistent with one previously adopted for the dielectric rod, based on the behaviour of field components as well as on the sequence of solutions. Computed 2- and 3-dimensional field configurations are shown for the HE11 and EH11 modes. The second aspect is concerned with the propagation characteristics for all modes. Expressions are derived for power flow, energy storage and power loss using a perturbation method, giving expressions for group velocity and attenuation coefficient. It is indicated that a certain configuration of the dielectric-tube waveguide may be practicable at the higher microwave frequencies