An apparatus, system, and method for performing electron beam modulation includes an input pulser to provide an electromagnetic pulse; a radio frequency (RF) filter to filter the electromagnetic pulse; a nonlinear transmission line to receive the electromagnetic pulse, and generate a backward wave RF oscillation of a predetermined frequency to travel in a direction opposite that of the electromagnetic pulse; and an electron beam generating device including an anode and a cathode, the electron beam generating device to receive a combined electromagnetic pulse from the RF filter and the backward wave RF oscillation from the nonlinear transmission line to cause excitation of a modulated voltage between the anode and cathode, and to cause the electron beam generating device to emit an electron beam that is modulated at the predetermined frequency of the backward wave RF oscillation.

A multibeam-inductive-output-tube amplifier comprises an output cavity and a plurality of electron guns each intended to emit an electron beam through the output cavity, each electron gun comprising a cathode intended to emit the electron beam and a gate allowing the density of the electron beam to be modulated. The amplifier comprises, associated with each gun, a DC voltage supply, each of the supplies connected to the gate of the corresponding electron gun so as to bias the gate. The voltage of at least one of the supplies is adjustable so as to balance the density of the various electron beams.

A multibeam-inductive-output-tube amplifier comprises an output cavity and a plurality of electron guns each intended to emit an electron beam through the output cavity, each electron gun comprising a cathode intended to emit the electron beam and a gate allowing the density of the electron beam to be modulated. The amplifier comprises, associated with each gun, a DC voltage supply, each of the supplies connected to the gate of the corresponding electron gun so as to bias the gate. The voltage of at least one of the supplies is adjustable so as to balance the density of the various electron beams.

The purpose is to make it possible to autonomously suppress a reduction in an electron beam without providing a means for supervising the electron beam intensity of a monitor or the like. An electron gun, provided with: a heater (12) in which one terminal serves as a heater terminal (H) and the other terminal serves as a shared terminal (HK), and in which a low-voltage power supply (21) is connected between the terminals, the heater (12) generating heat due to a current being supplied from the low-voltage power supply (21); and a cathode electrode (11) connected to the shared terminal (HK) and heated by the heater (12) to discharge thermal electrons. A cathode current (Ik) due to the thermal electrons discharged from the cathode electrode (11), and a current (Ih) due to the low-voltage power supply, flow in opposite directions through the heater (12).

The purpose is to make it possible to autonomously suppress a reduction in an electron beam without providing a means for supervising the electron beam intensity of a monitor or the like. An electron gun, provided with: a heater (12) in which one terminal serves as a heater terminal (H) and the other terminal serves as a shared terminal (HK), and in which a low-voltage power supply (21) is connected between the terminals, the heater (12) generating heat due to a current being supplied from the low-voltage power supply (21); and a cathode electrode (11) connected to the shared terminal (HK) and heated by the heater (12) to discharge thermal electrons. A cathode current (Ik) due to the thermal electrons discharged from the cathode electrode (11), and a current (Ih) due to the low-voltage power supply, flow in opposite directions through the heater (12).

An electron emitter device is provided comprising a cathode comprising a conductive transition metal perovskite oxide comprising mobile conducting electrons exhibiting a conductivity of at least 10.sup.6 .sup.1-cm.sup.1 at room temperature, the transition metal perovskite oxide having a surface from which the mobile electrons are induced to emit upon receiving sufficient energy from an energy source; and an anode electrically coupled to the cathode and positioned to define an interelectrode conductive region between the anode and the cathode, onto which anode the emitted electrons are collected. The transition metal perovskite oxide may have formula Sr.sub.1-xBa.sub.xVO.sub.3. Related methods and devices based on the electron emitter device are also provided.

An electron emitter device is provided comprising a cathode comprising a conductive transition metal perovskite oxide comprising mobile conducting electrons exhibiting a conductivity of at least 10.sup.6 .sup.1-cm.sup.1 at room temperature, the transition metal perovskite oxide having a surface from which the mobile electrons are induced to emit upon receiving sufficient energy from an energy source; and an anode electrically coupled to the cathode and positioned to define an interelectrode conductive region between the anode and the cathode, onto which anode the emitted electrons are collected. The transition metal perovskite oxide may have formula Sr.sub.1-xBa.sub.xVO.sub.3. Related methods and devices based on the electron emitter device are also provided.

A carburized La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo filament cathode and its fabrication method, which belongs to the technical field of rare earth-refractory metal cathodes. The rare earth oxides are La.sub.2O.sub.3 and Lu.sub.2O.sub.3, and the total concentration of rare earth oxides ranges from 2.0-5.0 wt. %. The La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped molybdenum oxide powers are prepared by Sol-Gel method. La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo powers are prepared by two calcining steps. Then pressing and sintering the mixed powders to obtain the molybdenum rods; operating mechanical and heat processes of the molybdenum rods to obtain molybdenum filament. Operating electrolytic cleaning, straightening, winding modeling and cutting treatments with Mo filament to obtain the un-carburized La.sub.2O.sub.3 and Lu.sub.2O.sub.3 co-doped Mo cathode. And then carburize the filament cathode at a high temperature for a short time to obtain a cathode with high carburization degree. And then operate the out-gassing treatment and activation treatment with the cathode at a high temperature to obtain an environmental and non-radioactive cathode with good emission current and emission stability.

Provided are a traveling wave tube and a high-frequency circuit system such that the product life span of the traveling wave tube operating in multiple modes can be extended while variations in gain and amplification efficiency that accompany switching of the operation modes can be suppressed. The traveling wave tube comprises: an electron gun equipped with a cathode that releases electrons, and a heater that provides the cathode with heat energy for releasing the electrons; a helix causing an RF signal to interact with an electron beam formed from the electrons released by the electron gun; a collector for catching the electron beam emitted by the helix; an anode whereby the electrons released from the electron gun are guided into the helix; and a magnetic field application device for generating a magnetic field in order to change the diameter of the electron beam, said magnetic field application device being supplied with electric power for generating the magnetic field from the outside.

Provided are a traveling wave tube and a high-frequency circuit system such that the product life span of the traveling wave tube operating in multiple modes can be extended while variations in gain and amplification efficiency that accompany switching of the operation modes can be suppressed. The traveling wave tube comprises: an electron gun equipped with a cathode that releases electrons, and a heater that provides the cathode with heat energy for releasing the electrons; a helix causing an RF signal to interact with an electron beam formed from the electrons released by the electron gun; a collector for catching the electron beam emitted by the helix; an anode whereby the electrons released from the electron gun are guided into the helix; and a magnetic field application device for generating a magnetic field in order to change the diameter of the electron beam, said magnetic field application device being supplied with electric power for generating the magnetic field from the outside.