A nonlinear theory for coupled-cavity TWTs in beam-wave interaction

A frequency-dependent nonlinear analysis of coupled-cavity traveling-wave tubes is presented. The coupled-cavity structure is modeled by an equivalent circuit called Curnow and the electrons beam is regarded as a series of 1-D disks. Several favorable comparisons of model predictions with experimental measurements, including output power versus frequency is illustrated. The theory is capable of treating multiple drive frequencies and the associated intermodulation products. An example about the computation of C3IM and C5IM is also illustrated.