Propagation characteristics of the TM01 surface-wave mode in dielectric-lined coaxial cables

Accurate calculations of the propagation coefficients of the TM01 surface-wave mode in coaxial cables with dielectric linings on the inner, outer or both conductors were carried out using a perturbation method, and were checked by solving the exact characteristic equations. The calculations show that the perturbation method yields very accurate results, and that the attenuation coefficients cannot be reduced below that of the quasi-TEM mode in the unlined cable.