The influence of bends and ellipticity on the attenuation and propagation characteristics of the H01 circular waveguide mode

The generation and propagation of the H01 circular waveguide mode is discussed in the light of such theory as is at present available and of certain new experimental results. The Jouguet theory of propagation in curved circular guides has been verified at a wavelength of 3.2 cm. The attenuation of the H01 mode has been measured at 3.2 cm by a multiple-reflection technique in a long closed copper waveguide of 4¿-in diameter. The result obtained, namely 3.4 db/km, is about three times the theoretical figure, the excess being explainable in terms of losses due to surface roughness and ellipticity of the waveguide.