Magnetron harmonic generation

Computer experiments on conventional magnetrons have shown that the space-charge spokes are very narrow compared to their spacing, and therefore possess a high harmonic content. To couple out one of the harmonics, one has to tune the anode block so that its π-mode resonates at the fundamental frequency and the harmonic frequency desired, which has been found possible in scaled-up physical experiments. The measured impedance of the unloaded (high Q) fundamental and a low Q impedance in the third harmonic were programmed into further computer experiments with the encouraging result that the new loading conditions do not severely change the sharpness of the spokes, and that an overall efficiency as high as 28 percent can be achieved in third harmonic generation.