Energetics of laddertron with reflective or through-pass grating in the regime of Wood's anomalies

We reach good energetics of self-excitation at work of the generator on higher synchronous field's-harmonics. For this we correctly choose parameters of the grating for interaction with an electronic stream. It concerns to the laddertron and to other types the generators of diffraction radiation (GDR). We essentially improve energetics, if we transfer from a quasi-statics to the regime of Wood's anomalies. And it contrary to counteraction of ohmic losses, which we noticeably diminish, if we replace a reflective grating by through-pass grating, excited by two electron beams.