Ohmic Losses Influence on Excitation of Diffraction Radiation Oscillator on High Order Space Harmonics

The report discusses experimental results obtained in an effort to compare the DRO operation features in the case of excitation on the first, second and third space harmonics of the reflecting diffraction grating placed inside the same open resonant system (ORS). It will be shown that the choice of ORS provides DRO excitation on the high-order space harmonics almost without the starting current increasing.