Analytical theory of frequency-multiplying gyro-traveling-wave-tubes

The theory is developed which describes analytically the gain and bandwidth in frequency-multiplying gyro-traveling-wave-tubes. In this theory the inp ut waveguide is considered in the small-signal approximation. Then, in the drift region separating the input and output waveguides, the electron balli stic bunching evolves which causes the appearance in the electron current d ensity of the harmonics of the signal frequency. The excitation of the outp ut waveguide by one of these harmonics is considered in a specified current approximation. This makes the analytical study of a large-signal operation possible. The theory is illustrated by using it to analyze the performance of an existing experimental tube. (C) 2001 American Institute of Physics.