A Novel Technique of Power Control In Magnetron Transmitters For Intense   Accelerators
  A novel concept of a high-power magnetron transmitter allowing dynamic phase and power control at the frequency of locking signal is proposed. The transmitter compensating parasitic phase and amplitude modulations inherent in Superconducting RF (SRF) cavities within closed feedback loops is intended for powering of the intensity-frontier superconducting accelerators. The concept uses magnetrons driven by a sufficient resonant (injection-locking) signal and fed by the voltage which can be below the threshold of self-excitation. This provides an extended range of power control in a single magnetron at highest efficiency minimizing the cost of RF power unit and the operation cost. Proof-of-principle of the proposed concept demonstrated in pulsed and CW regimes with 2.45 GHz, 1kW magnetrons is discussed here. A conceptual scheme of the high-power transmitter allowing the dynamic wide-band phase and mid-frequency power controls is presented and discussed. 
G. Kazakevich, R. Johnson, M. Neubauer (MUONS Inc., Batavia) V.   Lebedev, W. Schappert, V. Yakovlev (Fermilab)
physics.acc-ph