Abstract: A power supply apparatus for a traveling-wave tube includes an electrical discharge switch and a first resistor that are serially connected, and that are connected between a cathode electrode and a first collector electrode; N (N denotes a positive integer) arresters that are serially connected, and that are inserted between a ground potential and a connection node of the electrical discharge switch and the first resistor; N second resistors that are inserted between the N arresters and a second collector electrode to an Nth collector electrode and a ground potential, respectively; and an electrical discharge control circuit that turns off the electrical discharge switch at a time of normal operation of the power supply apparatus and turns on the electrical discharge switch when stopping operation of the power supply apparatus.

Abstract: A beam of charged particles (e.g., an electron beam) from a charged particle source can be selectively applied to a pair of electrodes. For example, the charged particles can be electrons that are directed toward a first electrode when the charge difference between the electrodes is in one state and directed toward the second electrode when the charge difference between the electrodes is in another state. The electrodes are configured so that the beam of charged particles oscillates between the first and second electrodes.

Abstract: In one embodiment, a high frequency quasi optical oscillator power source is provided which includes an array of amplifier devices each having an input antenna tuned for a fundamental frequency. A amplifier coupled to the input antenna amplifies fundamental frequency signals. A multiplier coupled to the amplifier provides signals at a multiple of the fundamental frequency and at the fundamental frequency. The output antenna coupled to the multiplier is tuned at the fundamental frequency and at a multiple of the fundamental frequency. A grating lobe-to-main lobe converter located above the array of amplifier devices converts grating lobe power to main lobe power at the multiple of the fundamental frequency. A frequency selective reflector opposes the amplifier array to reflect signals at the fundamental frequency and to pass signals at the multiple of the fundamental frequency.

Abstract: Embodiments of High-Power Millimeter-Wave Oscillators are generally described herein. Other embodiments may be described and claimed. In some embodiments, the oscillator includes a polarized partial reflector to at least partially reflect back signals to a reflection array amplifier to help induce oscillation by individual sub-array amplifier elements of the reflection array amplifier. In some other embodiments, the oscillator includes a phase-graded polarization-sensitive reflection plate to at least partially reflect back signals to the reflection array amplifier to help induce an oscillation by the sub-array amplifier elements. In some embodiments, the oscillator includes a reflector and a phase-graded polarized reflection-transmission plate to at least partially pass through signals to the reflector for reflection back to the reflection array amplifier to help induce an oscillation by the sub-array amplifier elements.

Abstract: An apparatus for use with an accelerator includes a circulator having a first port, a second port, a third port, and a fourth port, wherein the first port is configured to couple to a power generator, and the third port is configured to couple to an accelerator, a first phase shifter coupled to the second port, and a second phase shifter coupled to the fourth port. A method of regulating power to and from an accelerator includes providing power using a power generator, varying a magnitude of the power before the power is delivered to the accelerator, receiving a reflected power from the accelerator, and varying the phase of the reflected power from the accelerator. A method of regulating reflected power from an accelerator includes receiving a reflected power from an accelerator, varying the phase of the reflected power, and varying a magnitude of the reflected power.

Abstract: The subject of the present invention is a very high-power microwave generator using the virtual cathode effect.

Abstract: An electromagnetic wave amplifier and an electromagnetic wave generator operate using electron beams in a vacuum environment. The amplifier, arranged in a vacuum environment, comprises an electron emitting section for emitting electron beams and an amplifying section for amplifying an inputted electromagnetic wave in one direction by utilizing energy received from an electron beam emitted from the electron emitting section and traveling in the vacuum along a dielectric waveguide having a wave-shaped form. The generator, also arranged in a vacuum environment, comprises an electron emitting section for emitting electron beams and an oscillating section for generating an electromagnetic wave by utilizing electron beams emitted from the electron emitting section and travelling in the vacuum along a dielectric waveguide having a composite wave-shaped form.

Abstract: The disclosure relates to a radiofrequency generator including an Inductive Output Tube with an electron gun followed by an anode, the gun being raised to a high voltage in use, means producing an input radiofrequency signal and means of transmitting it to said IOT such that it provides an output signal whose power is amplified compared to said input signal, wherein said means producing said input radiofrequency signal, said means transmitting it to said IOT and said gun are confined in an electrostatically screened enclosure that is electrically isolated from the potential of the anode and can be raised to a high voltage, said gun receiving its high voltage from said screened enclosure. The invention is applicable to very high power radiofrequency generators.

Abstract: A radial electron-beam-breakup transit-time oscillator (RBTO) provides a compact high power microwave generator. The RBTO includes a coaxial vacuum transmission line having an outer conductor and an inner conductor. The inner conductor defines an annular cavity with dimensions effective to support an electromagnetic field in a TEM.sub.00m mode. A radial field emission cathode is formed on the outer conductor for providing an electron beam directed toward the annular cavity electrode. Microwave energy is then extracted from the annular cavity electrode.

Abstract: A device for damaging electronic equipment has a millimeter wave generator, such as a gyrotron oscillator, for producing very high power millimeter waves. A beam former antenna forms the millimeter waves into narrow beams for distance transmission. An antenna coupled to the gyrotron directs narrow beams of the millimeter waves to selected targets, whereby the beams damage electronic equipment at the targets. The millimeter wave generator produces frequencies ranging from about 100 to 140 GHz at 20 millisecond megawatt pulses at 400 kilowatts CW.

Abstract: An electron beam generated by an electron gun is oscillated in a cavity resonator and output as a millimeter electromagnetic wave. The output electromagnetic wave is transmitted to a cylindrical mode converter. The inner wall surface of this mode converter has a plurality of sets of ridges and grooves spirally formed at equal pitches so as to gradually change the degree of corrugation in the transmission direction of the electromagnetic wave. The mode converter separates the input electromagnetic wave from the cavity resonator into a plurality of electromagnetic waves having the same power distribution. The output electromagnetic waves from the mode converter are transformed into wave beams by mirror systems and output to the outside of a gyrotron from output windows provided in a one-to-one correspondence with these electromagnetic waves.

Abstract: A system which integrates "intelligent" electronic feedback into the structure of vacuum electronic devices whose subcomponents are electronically and/or electro-mechanically adaptive. By "vacuum electronic device," is meant any source of microwave (or millimeter-wave) power generation which is driven by electron beams. Such a device is divided into the following main subsections: an electron emitter, an electron beam shaping & acceleration region, an rf signal input coupler (for amplifiers), an electron-beam drift region, at least one rf/beam interaction region where beam energy is converted to an rf signal, a beam-dump region, and the rf signal output coupler. Some of those subsections are instrumented with electronic sensors. The data collected by those sensors will feed into an "on-board" microcomputer (logic unit subsection 8) which will compare it to "ideal" set of values for those parameters.

Abstract: In a gyrotron apparatus, an oscillator tube unit and a collector are coupled by a bellows. The collector is received in an evaporation boiler jacket. The oscillator tube is supported on a stand and the collector and the boiler jacket is supported on the other stand.

Abstract: An electron beam microwave device having an evacuated interaction chamber to which are coupled a resonant cavity which has an opening between the resonant cavity and the evacuated interaction chamber and an electron gun which causes a narrow beam of electrons to traverse the evacuated interaction chamber. The device also contains a mechanism for feeding back a microwave electromagnetic field from the resonant cavity to the evacuated interaction chamber in such a way as to modulate the direction of propagation of the electron beam, thereby further amplifying the microwave electromagnetic field. Furthermore, provision is made for coupling the electromagnetic field out of the electron beam microwave device.

Abstract: A gyrotron providing first and second microwave frequencies comprises a dual frequency cavity coupled between an electron gun and a waveguide. The electron gun, the dual frequency cavity and a segment of the waveguide are surrounded by a variable magnetic source having first and second operating states. The first state provides microwaves at the first frequency, while the second state produces microwaves at the second frequency.

Abstract: There is provided a gyrotron including a quasi-optical mode converter wherein a solid dielectric layer such as silicon carbide for absorbing unnecessary millimeter waves generated by diffraction of the quasi-optical mode converter is arranged in annular shape in the periphery of the quasi-optical mode converter, and millimeter absorption fluid can be supplied to the periphery of the mode converter in a predetermined direction through vacuum barrier walls formed by a dielectric member, thereby efficiently absorbing the diffracted millimeter wave which is the cause of generating heat.

Abstract: A compact device called the split cavity modulator whose self-generated oscillating electromagnetic field converts a steady particle beam into a modulated particle beam. The particle beam experiences both signs of the oscillating electric field during the transit through the split cavity modulator. The modulated particle beam can then be used to generate microwaves at that frequency and through the use of extractors, high efficiency extraction of microwave power is enabled. The modulated beam and the microwave frequency can be varied by the placement of resistive wires at nodes of oscillation within the cavity. The short beam travel length through the cavity permit higher currents because both space charge and pinching limitations are reduced. The need for an applied magnetic field to control the beam has been eliminated.

Abstract: A method and an apparatus for enhancing modulation of a relativistic electron beam are described. A relativistic electron beam having been modulated is produced and passed through a superconducting passage having a periodicity in the passing direction of said beam. The periodicity is coincident with the modulation of the beam so that the modulation of the beam is enhanced by interaction between the beam and the superconducting passage through electromagnetic fields. The modulated electron beam can be used for generating microwaves at low power consumption.

Abstract: A gyrotron having a mode converter located in the path of a wave passing passage, the mode converter comprising a means for mode-converting electromagnetic wave into a radiating electromagnetic wave having an annular-shaped power distribution in a plane perpendicular to the direction in which the electromagnetic wave propagates, a ring-shaped mirror (annular mirror) for reflecting the radiating electromagnetic wave which has been converted by the mode converting means, and a waveguide tube having a kerf (i.e., a cutting portion of the tube) opposed to the annular mirror to receive the electromagnetic wave reflected by the annular mirror.

Abstract: A quasi-optical component for microwave radiation comprises a quasi-optical element (16a) which radiates incident microwave radiation along a major axis (19) and which has a characteristic transverse dimension (D) which is smaller than 50-times one wavelength. It is distinguished by the fact that a cooled absorption device (17) is provided which is arranged closely in front of the quasi-optical element (16a) in such a manner that at least one high-power secondary peak (20) of the diffraction due to the characteristic transverse dimension is destroyed.

Abstract: In a gyrotron having an annular collector for an expanded e-beam and a gyrotron output waveguide with an annular gap for passing the expanded e-beam is provided with a mode converter between the resonator and the gap to shift more energy to the waveguide central axis to decrease EM field leakage coupling through said gap.

Abstract: The invention relates to a device for producing microwave energy from an electron beam. The device includes:an electron gun (1), allowing the production of an electron beam (8) in a so-called injection zone (3);a microwave modulation circuit (7), allowing the superimposition of an alternating voltage at a given frequency on the voltage of the beam in the injection zone; the amplitude of this voltage is sufficient for ensuring, during one of its alternations, the transition between the passing state and the virtual cathode state, thus causing a modulation of the current carried by the electron beam;an output microwave circuit (4) functioning at the frequency of the modulation signal and excited by the previous modulated current.

Abstract: An improved atomic beam clock apparatus and method are disclosed. The invention substantially reduces errors arising from Rabi pulling and variations in the frequency standard resulting from variations in the amplitude of the microwave signal used to excite the atomic beam. The invention includes a servo loop that adjusts both the microwave frequency and amplitude. The servo loop measures the output of a beam detector at two pairs of microwave frequencies. The output of the detector at each frequency in each pair of frequencies is measured for two different microwave amplitudes. The amplitude data is used to adjust the microwave power such that the output of the detector is maximized at each pair of frequencies. The amplitude modulation scheme of the present invention may also be applied very advantageously to conventional two point frequency modulation schemes.

Abstract: A quasi-optical gyrotron for the production of electromagnetic radiation in the form of mm waves has several high-power resonators. Resonators have two mirrors each lying on a resonator longitudinal axis aligned perpendicular to an electron beam axis. The electron beam axis is thus given by the path of the electrons forced to gyration by a static magnetic field. Resonator longitudinal axes are basically in a common plane perpendicular to the electron beam axis and form an angle greater than zero.

Abstract: In a quasi-optical gyrotron an electron beam (1) passes along an electron beam axis (2) and in so doing is compressed by a static magnetic field and forced into gyration, so that it excites in a quasi-optical resonator a standing alternating electro-magnetic field of given frequency. The resonator exhibits two mirrors (4a, 4b) arranged opposite to one another on a resonator axis (5) aligned perpendicular to the electron beam axis (2). In order to generate radiation in a wide frequency range, each of the two mirrors (4a, 4b) of the resonator is arranged in each case on a movable mount (8a, 8b) together with at least one further mirror (4c, 4d). In order to set a specific frequency of the alternating field, it is possible for two mirrors (4c, 4d), corresponding to one another and tuned to the desired frequency, to be brought onto the resonator axis by actuating the movable mounts (8a, 8b).

Abstract: In a quasi-optical gyrotron, two coils (3a, 3b) in a Helmholtz arrangement generate a static magnetic field which is axially symmetrical with respect to an electron beam axis (2). As a result, the electrons passing along the electron beam axis (2) parallel to the magnetic field are forced into gyration and excite an alternating electromagnetic field in a quasi-optical resonator. The resonator comprises two mirrors (4a, 4b) which are arranged opposite to one another on a resonator axis (5) and which exhibit a superconducting reflective surface (6a, 6b). The resonator axis (5) is aligned perpendicularly to the electron beam axis (2) between the two coils (3a, 3b). So that the superconduction is not impaired by the strong magnetic field, means for suppressing the magnetic field at the location of the mirros (4a, 4b) are provided. These means preferably comprise a yoke (10) of a material having a high magnetic permeability.

Abstract: In a quasi-optical gyrotron which exhibits a quasi-optical resonator having two mirrors (4a, 4b) which opposite one another on a resonator axis (5), the required electromagnetic radiation is coupled out by means of a hologram. In this arrangement, at least one of the two mirrors (4b) of the resonator exhibits a reflective surface (8b) provided with a hologram. The hologram is constructed in such a manner that the radiation to be coupled out is scattered in the direction of at least exactly one coupling-out axis (10), the at least exactly one coupling-out axis (10) enclosing a predetermined angle .alpha. not equal to zero with the resonator axis (5). The angle .alpha. is preferably as small as possible.

Abstract: A microwave generator that uses an electron beam and the phenomenon of the oscillating virtual cathode, but makes it possible to obtain energy with improved spectral quality and conversion efficiency as compared with standard vircator generators. This is achieved by the separate use of the electrons coming from the virtual cathode (80), that is, transmitted electrons (80) or reflected electrons (81) to convert their kinetic energy into microwave energy (4).

Abstract: The present invention provides a vircator with improved efficiency. An elongated anode is aligned with an elongated cathode so as to produce an elongated virtual cathode when a direct current voltage source is electrically connected to the elongated cathode. A surface wave having a velocity near the velocity of light will be produced on the virtual cathode. Waveguide means enclosing the virtual cathode is disposed so as to propagate microwave radiation in a direction parallel to the direction of elongation of the cathode, anode and virtual cathode. The waveguide is designed to match the phase velocity of the microwave to the velocity of the virtual cathode surface wave.

Abstract: A microwave generator is provided for generating microwaves substantially from virtual cathode oscillation. Electrons are emitted from a cathode and accelerated to an anode which is spaced apart from the cathode. The anode has an annular slit therethrough effective to form the virtual cathode. The anode is at least one range thickness relative to electrons reflecting from the virtual cathode. A magnet is provided to produce an optimum magnetic field having the field strength effective to form an annular beam from the emitted electrons in substantial alignment with the annular anode slit. The magnetic field, however, does permit the reflected electrons to axially diverge from the annular beam. The reflected electrons are absorbed by the anode in returning to the real cathode, such that substantially no reflexing electrons occur. The resulting microwaves are produced with a single dominant mode and are substantially monochromatic relative to conventional virtual cathode microwave generators.

Abstract: A generator of short electromagnetic waves is provided with a novel form of resonant cavity having improved mode selectivity. The reflecting walls of the cavity correspond to a surface of revolution and the meridian planes include four discrete mirror zones which face each other and are positioned so that the centers of the mirror zones form the vertex of a polygon and the normals to said mirror zones at the centers are bisectors of the angles formed at the vertices of the polygon.

Abstract: A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

Abstract: An autogenerating apparatus provides secondary intense relativistic current beam pulses in response to an injected beam pulse. One or more electromagnetic energy storage devices are provided in conjunction with gaps along a beam propagation path for the injected beam pulse. For injected beam pulses which are no longer than double the transit time of electromagnetic waves within the storage devices (which may be resonant cavities), distinct secondary beam pulses are generated by each of the energy storage devices. The beam propagation path, together with the one or more gaps provided therein, operates as a pulse forming transmission line cavity, in which the separate cavities associated with the gaps provide delays for electromagnetic waves generated at the gaps. After doubly traversing the cavity, the electromagnetic waves cause the gap to generate the secondary beam pulses, which are thus delayed by a time interval equal to the double transit time for the induced wave within the cavity.

Abstract: An improved gyrotron oscillator or gyrotron amplifier having a plurality of trong-field magnetic arrays disposed along the length of the device. Each magnetic array comprises n electromagnets, the windings of which are arranged so that the polarity of the electromagnets alternates around each array. Further, the polarity of the corresponding magnets in successive arrays alternate axially along the device. The strong-field magnetic arrays focus and reshape the electron beam within the gyrotron, thereby increasing the efficiency of the device. Permanent magnets may be used in lieu of electromagnets but offer less control.

Abstract: Coherent microwave radiation is generated in and transmitted through a waveguide/drift tube by means of an injected relativistic electron beam the parameters of which, in combination with the waveguide/drift tube geometry and dimensions effect a virtual cathode oscillation condition within the waveguide/drift tube. Tuning of the device is accomplished by manipulation of the relativistic electron beam parameters and/or waveguide/drift tube physical dimensions.

Abstract: The device of the invention comprises a body of dielectric material having a metallic surface on one portion thereof. An electron beam is passed adjacent a second portion of the dielectric body in order to generate electromagnetic radiation in the dielectric. A feedback loop is provided to improve the coherence of the radiation output.

Abstract: A high frequency electromagnetic wave generator is disclosed which comprises an electron gun which directs an electron beam through a region generally adjacent a diffraction grating. The grating cooperates with an opposed reflecting surface to produce a standing electromagnetic wave. The reflector comprises a highly reflective dielectric coated mirror. Supporting means for the diffraction grating may also comprise a reflective dielectric surface.

Abstract: A method and apparatus for producing high power, coherent microwave radiaton in which a beam of high speed (above 0.5 light speed) electrons are propagated through a linear path in a waveguide tube including low dielectric constant material adjacent the path so that the electromagnetic radiation is slowed in the material and the beam coupled to the radiation. The beam is focussed and guided to destabilize the guided electro-magnetic modes and to convert the beam energy into high power, high frequency, coherent microwave radiation.