Effects of random circuit fabrication errors on the mean and standard deviation of small signal gain and phase in a traveling wave tube

This paper summarizes a calculation of the mean and standard deviation of the small signal gain and phase of a TWT in the presence of small random, axially varying perturbations in the circuit phase velocity using numerical and analytic approaches. The analytical results compare favorably with results from numerical computations in the absence of space charge effects. The effects of small pitch errors in a 210 GHz folded waveguide TWT are evaluated in an example.