High power Ka-band and Q-band helix-traveling wave tubes for communications and radar applications

Latest capability in millimeter-wave helix-TWTs demonstrated at L-3 Communications Electron Technologies (L-3 ETI), Inc. (formally Boeing Electron Dynamic Devices, Inc. and originally Hughes Electron Dynamics Division) in CW output power and the overall efficiency of Ka-band and Q-band devices are presented. The 8921HP, L-3 ETI's standard high power communications Ka-band TWT model, produces 250 W minimum CW output power and 47% overall efficiency with a two-stage collector over 27.5 GHz-31 GHz. The 8921HP-2, a variation of the 8921HP, generates 300 W output power over 28.3 to 30 GHz and 50% overall efficiency. Another Ka-band device, the 8922HP, developed for pulsed radar applications over 33.4 GHz-36 GHz, produces 230 W minimum output power over the bandwidth with 49 % minimum overall efficiency. This device was developed for pulsed operations, but has demonstrated CW power handling capability up to 270 W, In Q-band, the 8925HP, derived from the current production 120 W Q-band helix-TWT (8905HP), significantly extends the CW output power capability, demonstrating 230 W minimum over 43.5 GHz-45.5 GHz. The 8925HP is presently in the second phase of development to be production ready for 200 W output power