Pulsed depressed collector
View Patent ↗A high power RF device has an electron beam cavity, a modulator, and a circuit for feed-forward energy recovery from a multi-stage depressed collector to the modulator. The electron beam cavity include a cathode, an anode, and the multi-stage depressed collector, and the modulator is configured to provide pulses to the cathode. Voltages of the electrode stages of the multi-stage depressed collector are allowed to float as determined by fixed impedances seen by the electrode stages. The energy recovery circuit includes a storage capacitor that dynamically biases potentials of the electrode stages of the multi-stage depressed collector and provides recovered energy from the electrode stages of the multi-stage depressed collector to the modulator. The circuit may also include a step-down transformer, where the electrode stages of the multi-stage depressed collector are electrically connected to separate taps on the step-down transformer.
1. A high power RF device comprising:
an electron beam cavity having a cathode, an anode, and a multi-stage depressed collector;
a modulator configured to provide pulses to the cathode; and
a circuit connected to the modulator and to electrode stages of the multi-stage depressed collector,
wherein the circuit comprises a storage capacitor that dynamically biases potentials of the electrode stages of the multi-stage depressed collector and provides recovered energy from the electrode stages of the multi-stage depressed collector to the modulator.
2. The device of claim 1 wherein the circuit further comprises a step-down transformer.
3. The device of claim 2 wherein a high-voltage (primary) side of the step-down transformer is coupled to the multi-stage depressed collector, wherein a low-voltage (secondary) side of the step-down transformer is coupled to the storage capacitor, and wherein the storage capacitor is coupled to the modulator.
4. The device of claim 2 wherein the electrode stages of the multi-stage depressed collector are electrically connected to separate taps on the step-down transformer.
5. The device of claim 1 wherein voltages of the electrode stages of the multi-stage depressed collector are allowed to float as determined by fixed impedances seen by the electrode stages.