Nonlinear Theory of a Corrugated Coaxial- Gyrotron With Misaligned Inner Rod

The effects of a small misalignment of the inner rod in a corrugated coaxial-gyrotron on eigenvalue, resonant frequency, and electronic efficiency, and so forth, are presented. As a practical application, with the electronic velocity spread and cavity wall resistivity being taken into account, the beam-wave interaction of a 170 GHz megawatt corrugated coaxial-gyrotron operating with TE_31,12 mode has been investigated. The results show that the eigenvalue increases slightly when the ratio of misalignment to outer radius D/R increases in the case of small ratio of outer to inner radius C= R/R_in, but is uniform in the case of large ratio of C . The electronic efficiency decrease slightly when D/R increases within the range of 0-0.01. If D/R increases to 0.02, the efficiency decreases seriously to only about 5%. For both cold cavity and hot cavity, the resonator frequency increases with D/R increasing.