Intermodulation products in a klystron

Summary form only given. A general theory of intermodulation in klystron amplifiers has recently been developed. The algorithm computes intermodulation products (IMP) of all orders, including harmonic generation at each gap in a multi-cavity klystron. It takes into account the combined effects of charge-overtaking and space charge force. It has great accuracy and spectral resolution. A figure shows the code validation against experiments at the University of Wisconsin. We shall present calculations of IMP with three drive signals, a subject of considerable interest to JPL's Deep Space Network, where three space probes orbiting Mars may be subject to intermodulation distortion. We also explore the possibility of suppressing the third order intermod (IM3) that results from two main drive signals by externally injecting a much weaker signal at the same frequency as IM3.