Single-stage depressed collectors for gyrotrons

Experimental observation of the effect of aftercavity interaction in a depressed collector gyrotron oscillator

“…Thus, depressed collectors allow a major efficiency enhancement in gyrotrons. 1,2 In theory, multistage depressed collectors are possible, but have not yet been demonstrated experimentally in gyrotrons. [3][4][5] Depressed collectors cannot only enhance the overall efficiency greatly but also reduce the power loading on the collector, which facilitates longpulse operation of gyrotrons and reduces the possibility of collector failure due to metal fatigue.…”

Separation of energy fractions of an electron beam by a localized nonuniformity of magnetic field in the collector region of gyrodevices

“…The described magnetic separator can be used for (i) additional increase in the efficiency of energy recovery in gyrotrons with favorable structure of the high-frequency field [12]; (ii) energy recovery in gyrotrons at gyrofrequency harmonics and in gyroamplifiers, in which minimum energy of electrons at the output of the interaction space is so small that the simplest one-stage energy recovery [1][2][3][4] becomes inefficient. This work was supported by the Russian Foundation for Basic Research (project Nos.…”

“…ficiency is deposition of the used electron beam onto the collector whose potential is lower than the cavity potential [1][2][3]. In this case, a significant deceleration of electrons without their reflection is possible if the minimum energy of electrons in the used beam is sufficiently high.…”

Optimization of the Cavity Length of the Gyrotrons Operated at the Second Gyrofrequency Harmonic with One-stage Recovery of the Residual Energy of an Electron Beam

“…In gyrotrons, energy recovery has been realized fairly recently (see, e.g., [1,2]) and is now used only in high-power tubes operated at the first cyclotron harmonic [4]. This paper considers weakly relativistic gyrotrons (with accelerating voltages below 100 kV) operated at the second gyrofrequency harmonic.…”

“…Recovery of the residual energy of an electron beam is currently one of the main ways to improve the gyrotron efficiency [1][2][3]. In gyrotrons, energy recovery has been realized fairly recently (see, e.g., [1,2]) and is now used only in high-power tubes operated at the first cyclotron harmonic [4].…”