  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.
