1. Institute for Plasma Research MURI 99 Frequency Doubling Harmonic Gyro-TWT’s (development and experimental studies) We will complete the optimization of operating parameters and measurements of output power, gain, bandwidth, efficiency, phase noise and stability of the Ka-band TE 03 frequency doubling gyro-TWT by Dec. 1999. The device is predicted to produce output power at 35 Ghz of more than 200 kW with 30 dB gain, a bandwidth of nearly 1%, efficiency at least 20%, mean phase deviation less than 2 degrees and be zero drive stable.

2. Institute for Plasma Research MURI 99 Frequency Doubling Harmonic Gyro-TWT’s (development and experimental studies) A new frequency multiplying, harmonic gyro-TWT is currently under development. Simulations of the TE 0n fundamental input and harmonic output circuits show that more than 5% bandwidth may be achievable. Cold testing of the structures and plans to fabricate the tube are underway. Input Mode Launcher and Converter Extended Interaction Output Circuit

3. Institute for Plasma Research MURI 99 Novel Fast-wave Amplifier Concepts (Theory) Nonlinear theory of two-stage gyro-TWT’s operating –at the fundamental cyclotron resonance, –in the frequency doubling regime. Theory of a gyro-TWT with a waveguide partially loaded with a lossy dielectric for realizing stable, high gain operation.