Design and evaluation of a linearized C-band helix TWT for digital communications experiments
Reduction in amplifier distortion is often achieved by backing-off from saturation. As an alternative to aggressively backing-off in output power to meet new demands of linearity, this work explores techniques to optimize the pitch profile of TWT helices to reduce distortion. A C-band helix TWT circuit optimized for linearity was designed at NRL and subsequently built by Northrop Grumman. We describe the circuit design and the design methodology, and compare the measured TWT performance with model predictions.