High-power hyperfrequency emission tube

A tube for emitting high power electromagnetic waves which comprises, in a vacuum envelope:

• means for generating and focussing an electron beam;
• a plurality of energy collecting means formed by circuits of the hyperfrequency type which modulate the electron beam and extract the useful energy in the form of a signal of very high frequency F;
• a plurality of means for accelerating the electrons of the beam formed by hyperfrequency circuits comprising a resonant cavity with an input to which is applied in operation an hyperfrequency signal of frequency f such that f/F=.OMEGA./.omega.=.phi./.theta..multidot.1 /ND.sub.c,
• where:
• .OMEGA.=2.pi.f;
• .omega.=2.pi.F;
• .phi. is the transit angle existing between two consecutive accelerating means;
• .theta. is the interaction angle existing between the electron beam and the useful signal of frequency F;
• D.sub.c is the spatial period of the collecting means uniformly distributed with the accelerating means, of spatial period
• D.sub.a, along the path of the electron beam and in its direction of propagation;
• N is the number of collecting means comprised between two accelerating means;
• the spatial period D.sub.a of the accelerating means being equal to a whole multiple k of the spatial period D.sub.c
• of the collecting means and the accelerating means restoring to the electron beam the energy lost at the level of the collecting means.