Abstract:
A solid state Klystron structure is fabricated by forming a source contact and a drain contact to both ends of a conducting wire and by forming a bias gate and a signal gate on the conducting wire. The conducting wire may be at least one carbon nanotube or at least one semiconductor wire with long ballistic mean free paths. By applying a signal at a frequency that corresponds to an integer multiple of the transit time of the ballistic carriers between adjacent fingers of the signal gate, the carriers are bunched within the conducting wire, thus amplifying the current through the solid state Klystron at a frequency of the signal to the signal gate, thus achieving a power gain.
Abstract:
A terahertz sheet beam klystron (TSBK) includes an electron gun configured to generate a sheet electron beam and a drift tube through which the sheet beam is propagated. The drift tube is provided with multiple resonant cavities and includes a drift tube circuit including an input RF circuit through which an input RF signal is introduced and an output RF circuit through which an output RF signal is extracted, a collector, and a vacuum envelope. The output RF circuit is configured such that Qe (extraction Q) of the drift tube circuit is comparable to Q0 (unloaded Q) of the drift tube circuit, thereby improving the efficiency of the drift tube circuit.
Abstract:
A low-voltage, multi-beam, multi-MW RF source that operates at a voltage less than or equal to approximately 60 kV and generates at least one MW. The RF source includes a cathode configured to generate a plurality of beamlets. An input cavity and output cavity are common to the plurality of beamlets. A plurality of gain cavities are provided between the input and output cavities, each having a plurality of openings corresponding to the plurality of beamlets. The power source may further include a plurality of cathodes, each cathode generating a plurality of beamlets, wherein the input and output cavities are common to the plurality of beamlets from each of the plurality of cathodes, and a separate set of gain cavities are provided for each cathode. A single cathode version generates approximately 2.5 MW, and a four cathode version having four independent cavity systems and a common magnetic system generates approximately 10 MW.
Abstract:
A microwave tube including: a) an electron gun capable of producing a beam of electrons in the form of a hollow axisymmetrical cylinder in repetitive operation; and b) a body in which the beam is intended to propagate, the body ending with a collector and being provided with means for applying an axial magnetic field for guiding the beam and, upstream from the collector, with a resonant structure crossed by the beam, intended to group the electrons into a succession of packets (P). The resonant structure is formed with two coupled cavities which follow along the axis (Z) of the beam, the coupling being achieved via an inter-cavity region crossed by the beam, this structure having axial symmetry the axis of which is that of the beam and being dimensioned so that the transformation of the electrons in packets is accomplished at a frequency which is that of the π resonant mode of the resonant structure.
Abstract:
The present invention provides a multi-beam klystron apparatus. In the above-described multi-beam klystron apparatus, the magnetic field generating element of the electron-gun-unit-side magnetic field generating unit is disposed around the electron gun unit, and a plurality of magnetic gaps are provided in the inner peripheral surface of the magnetic pole, which covers the magnetic field generating element, in the direction of travel of the electron beams. Therefore, lines of magnetic force, which are parallel to the center axis of the radio-frequency interaction unit, can be generated. Thus, even the electron beam, which is generated from the location apart from the center axis of the electron gun unit, can be guided to the radio-frequency interaction unit in the same manner as in the location at the canter axis of the electron gun unit.
Abstract:
A klystron has a plurality of electron beam paths and plural damped disc-shaped cavities. The plurality of electron beam paths cut the cavities and the Klystron amplifier further comprises an annular input cavity and an annular output cavity disposed around the substantially circular external periphery of respective disc-shaped cavities, and in communication with it. The output cavity is arranged to receive RF power from the electron beams, wherein the cavities are arranged to support one of a single resonant rotating wave in a whispering-gallery mode, and a single resonant standing wave in a whispering-gallery mode.
Abstract:
An improved Klystron device is disclosed which has opposed electrostatic (ES) magnetic field generating members which are uniformly spaced along a longitudinal axis to form an electron beam chamber. The ES magnetic field generating members produce a magnetic flux which confines an electron beam passing through the chamber when an alternating current (AC) is imposed upon the magnetic field generating members. An additional improvement includes a chamber formed from a single sheet of electron conductive metal having a ladder-like structure symmetrical about a longitudinal hinge which permits the structure to be folded about the hinge to form a suitable electron beam chamber.
Abstract:
An RF device comprising a plurality of drift tubes, each drift tube having a plurality of gaps defining resonant cavities, is immersed in an axial magnetic field. RF energy is introduced at an input RF port at one of these resonant cavities and collected at an output RF port at a different RF cavity. A plurality of electron beams passes through these drift tubes, and each electron beam has an individual magnetic shaping applied which enables confined beam transport through the drift tubes.
Abstract:
An electron gun provides multiple convergent beamlets in a rectilinear flow for use in multiple drift tubes of a multiple beam klystron. The electron gun comprises a cathode having a concave emitting surface and an anode having a concave surface defined by respective ends of a plurality of hollow drift tubes. The anode surface is spaced from the cathode surface and has a positive voltage potential applied thereto to define a series of equipotential contour surfaces between the cathode and the anode. A plurality of grids are located between the cathode and the anode, with each one of the grids being disposed coincident with a respective one of the equipotential contour surfaces with a first one of the grids located closely adjacent to the cathode surface. Each one of the grids further has a plurality of perforations extending therethrough in substantial registration with each other and with respective openings of the plurality of drift tubes. A plurality of electron beamlets are drawn from the cathode surface through respective ones of the plurality of perforations and into respective ones of the plurality of drift tubes.
Abstract:
Nonlinear current modulation of a relativistic electron beam is achieved byts propagation without interruption through a resistive wall type of drift tube assembly within a klystron amplifier. Maximized beam current modulation is thereby attained for a beam propagation distance within a shortened drift tube.