Fel-oscillator for Feeding of High-gradient Accelerating Structure

Millimeter-wave FEL-oscillator is one of a possible source of RF power for accelerating structures of future linear colliders with high energy gain. JINR-IAP collaboration develops a high-efficiency single-mode FEL-oscillator with a Bragg resonator and reversed guide field. Output power of 48 MW at the frequency of 30.6 GHz with spectrum width 0.25% was registered in recent experiments using induction linac LIU-3000 (0.8 MeV, 200 A, 200 ns). In this paper we discuss technical solutions for providing of: ƒ frequency stability with accuracy better than 0.3%; ƒ precise frequency coincidence of the oscillator and the accelerating structure; ƒ RF power transportation from the oscillator to the structure.