delayed reflection

We study gyrotron frequency locking by the external monochromatic wave and stabilization of gyrotron frequency by the wave reflected from the non-resonant or resonant load. Although in the last decades influence of the external monochromatic signal and the reflected wave at the gyrotron operation was studied in a number of publications, concrete schemes of gyrotron frequency stabilization weren’t discussed.

At the autooscillator with small reflection from the remote load the mode stability relative to decay into two side satellites was studied by numerical simulation of characteristic equation. At arbitrary exceed over oscillation threshold the stability regions was founded in the space of system parameters. The results are in a good agree, from the one hand, with theory in the parameter space where characteristic equation can be solved analytically, from the other hand, with the results of numerical simulation of transient processes between modes.

At the autooscillator with weakly reflected remote load the number of one­frequency states –longitudinal modes – increases with the growth of the reflection coefficient and the length of the delay line. A mode of this kind can be unstable in some parameter regions. There can be two types of perturbations: a) the perturbations resulting in a slow evolution of principal mode amplitude and frequency; b) the perturbations in the form of two satellites which frequencies are symmetric from that of the principal mode.