Abstract: Described is a miniature tunable filter, comprising at least two adjacent coaxial-type resonators coupled to one another. Each coaxial-type resonator comprises a metal-coated ceramic dielectric cavity having a tuning rod passage formed therethrough. A tuning rod is inserted through the tuning rod passage, such that the miniature tunable filter is tuned by moving the tuning rod into and out of the tuning rod passage of the ceramic dielectric cavity. A low impedance coaxial section surrounds at least a portion of the tuning rod to create an effective microwave short-circuit at a resonant frequency of the miniature tunable filter, which results in very wide tuning and low insertion loss. In a desired aspect, the tuning rod is a solid metal tuning rod. The combination of a solid metal tuning rod with a ceramic coaxial-type resonator results in high radio frequency power handling.

Abstract: Provided is a backward-wave oscillator in a communication system, including a waveguide formed of a metamaterial. A unit structure of the waveguide may include: a top plate; a short-circuited stub; a bottom plate separated at a predetermined gap from the top plate, and having the short-circuited stub formed in the center thereof; a first metal pillar connecting the top plate at a first port positioned on one surface based on the short-circuited stub to the bottom plate at a second port positioned on the opposite surface of the first port based on the short-circuited stub; and a second metal pillar separated from the first metal pillar, and connecting the top plate at the second port to the bottom plate at the first port.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: Various apparatuses and methods for a vacuum electronic device are disclosed herein. In one embodiment, a vacuum electronic device includes a vacuum housing, an array of slow wave structures inside the vacuum housing sharing a common electron beam tunnel, an electron beam input port at a first end of the common electron beam tunnel, and an electron beam output port at a second end of the common electron beam tunnel.

Abstract: Various apparatuses and methods for a vacuum electronic device are disclosed herein. In one embodiment, a vacuum electronic device includes a vacuum housing, an array of slow wave structures inside the vacuum housing sharing a common electron beam tunnel, an electron beam input port at a first end of the common electron beam tunnel, and an electron beam output port at a second end of the common electron beam tunnel.

Abstract: Disclosed herein is a class of mm and sub mm wavelength amplifiers and oscillators operating with miniature helical slow wave circuits manufactured using micro fabrication technology. The helices are supported by diamond dielectric support rods. Diamond is the best possible thermal conductor, and it can be bonded to the helix. The electron beam is transmitted, not through the center of the helix, but around the outside. In some configurations the RF power produced may be radiated directly from the slow wave circuit. The method of fabrication, which is applicable above 60 GHz, is compatible with mass production.

Abstract: A microwave system for driving a linear accelerator is provided. The inventive microwave system employs a plurality of magnetrons, at least one pulse generator to energize the magnetrons, means for synchronizing outputs from the magnetrons, and at least one waveguide for transmitting synchronized outputs or power from the magnetrons to a linear accelerator. The linear accelerator that is driven by the inventive microwave system demonstrates increased efficiency and dependability, higher energy and power outputs, as well as, different energy outputs that can take the form of successive pulses that alternate between at least two different energy levels.

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 device for providing electromagnetic oscillations in the sub-millimeter range comprising one or more electron beam generators for providing a first and a second electron beam and one or more magnetic field generators for focusing the first and second electron beams. The device may comprise an oscillator comprising a slow wave circuit having a structure of an electrically non-conducting material with metallized surfaces adjacent the first electron beam and an amplifier comprising a slow wave circuit having a structure of an electrically non-conducting material with metallized surfaces adjacent the second electron beam and electrically connected to said oscillator. The oscillator and amplifier may be formed on a single substrate utilizing a single deposition process. The oscillator and amplifier may be contained in a single vacuum envelope.

Abstract: The invention relates to a microwave tube comprising an electron gun generating an electron beam in a cylindrical microwave structure of the tube. The microwave structure delivers a microwave at one output. A collector for collecting electrons from the beam comprising at least one electrode that is mechanically coupled to the microwave structure via a dielectric, the mechanical coupling forming a radial waveguide for propagating spurious microwave radiation (Pr) from the tube. In order to attenuate the spurious radiation from the tube, the radial waveguide (Wg) includes at least one quarter-wave microwave trap having, at least at the operating frequency F of the tube, an open circuit for the microwave propagating in said radial waveguide for propagating spurious radiation.

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: First and second parallel conducting plates include arrayed conducting segments, preferably with specific spacing relative to each other and to the separation of the plates. Currents through the conducting segments are pulsed and phased to produce constructive but unequal interference on the two plates. Among other things, the net result of the interference can produce a net force on the device, and in that manner can be used for propulsion. Preferred devices have up 100 segments or more.

Abstract: A slow wave structure for coupling RF energy with an electron beam comprises a co-propagating RF section including a plurality of pins having a uniform separation from the plane of an electron beam axis. An output aperture is positioned a half wavelength from a reflection section comprising a change in depth of the pintles, such that RF energy reflected by the change in pintle depth is added to the RF energy traveling with the electron beam. One or more rows of pintles are removed in the region of the output aperture to enhance coupling to the output aperture. The device may include a beam shaper for shaping the electron beam to surround the pintles, and the beam shaper and pintles may share common channels which are longitudinal to the electron beam axis. The slow wave structure may operate in forward and backward wave modes, and may be used in conjunction with other structures to form amplifiers and oscillators.

Abstract: An array of carbon nanotube electron sources to make an integrated array of RF (radio frequency) sources in a single vacuum envelope. The RF sources can be printed circuit traveling wave tubes.

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: In a magnetically insulated line oscillator device having a cathode 11, a surrounding slow wave structure 15 has a tapered configuration so that the effective cavity depth in the slow wave structure 15 progressively diminishes along a part of the length of the device towards the power output end of the device.

Abstract: A four cavity, efficient magnetically insulated line oscillator (C4-E MILO) having seven vanes and six cavities formed within a tube-like structure surrounding a cathode. The C4-E MILO has a primary slow wave structure which is comprised of four vanes and the four cavities located near a microwave exit end of the tube-like structure. The primary slow wave structure is the four cavity (C4) portion of the magnetically insulated line oscillator (MILO). An RF choke is provided which is comprised of three of the vanes and two of the cavities. The RF choke is located near a pulsed power source portion of the tube-like structure surrounding the cathode. The RF choke increases feedback in the primary slow wave structure, prevents microwaves generated in the primary slow wave structure from propagating towards the pulsed power source and modifies downstream electron current so as to enhance microwave power generation.

Abstract: A microwave switch selectively directs a microwave signal along first and second signal paths. The switch includes a microwave transmission member, a microwave chamber formed by the transmission member for containing an ionizable gas, input and output ports formed by the transmission member to communicate with the microwave chamber and a triggered plasma generator which is configured to generate, in response to a voltage trigger signal, a trigger electron density N.sub.t in the gas. The microwave signal increases the trigger electron density N.sub.t to a reflective electron density N.sub.r. Consequently, the microwave signal is reflected along a first path from the input port when the trigger electron density N.sub.t is present and is directed along a second path to the output port when the trigger electron density N.sub.t is absent. A plurality of these microwave switches is arranged to form a tunable microwave short.

Abstract: Multiple radio frequency (RF) outlet ports are provided along the side of a slow wave tube to establish a distributed RF output in response to the transmission of an e.sup.- beam through the tube. The tube has a periodically rippled inner surface, and the outlet ports are spaced along the tube by substantially integral numbers of ripple periods. When implemented as a backward wave oscillator, RF power is extracted during a single pass through the tube; a travelling wave tube amplifier implementation is also possible. The separation of the RF extraction from the absorption of the e.sup.- beam at the end of the tube eliminates RF reflections and permits water cooling of the e.sup.- beam absorber. The RF extraction ports are also preferably configured as built-in mode converters from a TM.sub.01 cylindrical tube mode to a TE.sub.10 rectangular extraction mode, with four symmetrically arranged rectangular extraction waveguides at each extraction location combining their energies into a single TE.sub.10 output.

Abstract: In a peniotron, a hollow electron beam is generated from a cathode gun assembly and a DC magnetic field is applied to the electron beam from solenoid coils. Thus, each electron of the electron beam is gyrated into a resonant cavity and into propagating waveguide sections which are maintained in auto-resonant conditions so that the electrons interact with an electromagnetic waves of TE mode not only in the resonant cavity section but also in a waveguide section. Accordingly, the electromagnetic wave is oscillated in the resonant waveguide section and amplified in the propagating waveguide section in such a manner that the level of the electromagnetic wave in the resonant cavity section is far less than the output power from said propagating waveguide.

Abstract: Stabilizing a signal generating source by coupling a small amount of the output power through a bandpass filter tuned to the desired frequency and injecting the power back into the source. In another embodiment the filtered power may be increased by injection locking a smaller oscillator and using the output to stabilize the source, or the filtered power may be amplified in a reflection amplifier and injected into the source for stabilization.

Abstract: It is an object of the invention to provide a miniature traveling wave tube which will have most of the advantages of solid state circuitry but with higher efficiency and without being highly sensitive to temperature and various types of electromagnetic radiation and subatomic particles as are solid state devices.The traveling wave tube which is about 2.5 cm in length includes a slow wave circuit (SWS) comprising apertured fins with a top cover which is insulated from the fins by strips or rungs of electrically insulating, dielectric material.Another object of the invention is to construct a SWS of extremely small size by employing various grooving or etching methods and by providing insulating strips or rungs by various deposition and masking techniques.

Abstract: A solid state radar transmitter pulse modulator system capable of generating high power operating pulses having pulse width and pulse repetition rate agility and being programmable for output pulse current over a substantial range of peak current values to produce corresponding values of transmitter output power. A multi-stage cascade cross-field amplifier (CFA RF chain) is employed, each stage having its own pulse modulator comprised of one or more standard modules paralleled at the output to drive the corresponding CFA stage provides fail-soft operation. Means are included for protecting solid state circuits in the event of CFA or other component failures, for dynamically matching CFA and pulse transformer impedances, and for preventing BH curve "walk-up" during operation.

Abstract: Microwave oscillators and amplifiers which utilize a superconducting slow-wave circuit. The slow circuit is made from materials which exhibit superconductivity at relatively high critical temperatures. The slow wave circuit is integral with the device's vacuum housing. Coolant exterior to the vacuum housing maintains the circuit in the superconducting state. The slow-wave circuit, which protrudes into the vacuum housing provides modulation of an electron beam which traverses the interior of the vacuum housing. Output power is ultimately extracted from the slow wave circuit.

Abstract: A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

Abstract: A resonant cavity arranged for an electron beam to pass therethrough, is made of two spaced apart parallel substantially planar members movable with respect to each other in a direction perpendicular to their major surfaces, at least one of said members having a delay line structure on its inner face within the gap between said two members. Means are arranged for moving the members relative to each other so as to vary the spacing between said members, whereby the oscillation frequency is tuned easily. The resonant cavity can be used to realize wide-band extended interaction oscillators and klystron amplifiers.

Abstract: A digital cathode current control circuit for controlling the cathode current of a traveling wave tube (TWT) amplifier is disclosed. The cathode current control circuit includes circuitry for providing a comparison signal indicative of the occurrence and amplitude of TWT cathode current pulses; clocking circuitry responsive to the comparison signal for providing a clock signal delayed relative the occurrence of a cathode current pulse; comparison circuitry for comparing the comparison signal with predetermined reference signals indicative of a predetermined cathode current level, and for providing adjustment signals indicative of the adjustment of the TWT cathode current necessary to tend to achieve the predetermined cathode current; and counter circuitry clocked by the delayed clock signal for providing an output count in response to the adjustment signals.

Abstract: Free-electron lasers and masers are modified by eliminating the resonator cavity as such. The feedback mechanism, essential to oscillation, is distributed through and integrated with the transmission line which guides the electromagnetic wave at the active region where interaction with the electron beam takes place. The feedback structure is created by perturbations in the transmission line along the length thereof at the locations of the zero electric field lines of a desired oscillatory standing wave mode. The perturbations may take the form of axial, helical, and azimuthal deformation of the transmission line.

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 electron beam device which includes a vacuum enclosure which houses an electron gun for producing an annular beam of helically rotating electrons, an iris-loaded waveguide which is supplied with high frequency power and serves to create a high frequency electromagnetic field along the axis of the beam which has a longitudinal electric field component along the beam axis, and a resonator which abstracts high frequency energy from the beam. A coil surrounds the vacuum enclosure to provide a magnetic field of increasing strength with distance downstream in the region of the iris-loaded waveguards whereby the angular velocity of the electrons in the beam is increased with little change in the axial velocity.

Abstract: A gyrotron backward wave oscillator device is described which can be operated in a controlled and predictable manner. The device includes an evacuated waveguide section, an electron source at one end providing a spiral electron beam, a collector at the opposite end, means for producing a magnetic field parallel to the longitudinal axis of the waveguide section, and an output window, the parameters of the device being such as to support backward wave oscillation therein and to output same through the window.

Abstract: A ladder circuit especially useful in backward wave oscillators operating in the 500 GHz to 2,000 GHz range comprises a waveguide (10) having disposed therein transversely oriented slabs (16) which contact an upper wall (22) of waveguide (10). The edges of slabs (11) adjacent the physical center of waveguide (10) along which is directed an electron beam (19) have respective curved segments (11) and stubs (12) and (13) of electrically conductive, non-magnetic material supported thereon. The ends of slabs (16) include metal layers (17) and (18) at respective opposite ends to provide a conductive leakage path. A ridge bar (20) is attached to the inside of the bottom wall (21) of the waveguide (10) and includes a concave upper surface which partially straddles electron beam (19). The inside width of the waveguide (10) is approximately one-half wavelength as determined by the frequency of operation of the backward wave oscillator.

Abstract: This oscillator comprises a periodic structure line constituted by a succession of vanes having an orifice in which propagates a linear electron beam. This line is placed over a cavity constituted by a straight parallelepiped which has a rectangular base, whose dimensions are determined in such a way that it behaves like a waveguide at the cut-off frequency, along the longitudinal axis of the line and on a transverse magnetic or TM.sub.mn mode with m=1, 3, 5 etc. and n=1, 2, 3, 4 etc. Coupling slots are provided on the cavity between two successive vanes and in a gap between pairs of vanes. The anode voltage of the beam and the distance between two successive vanes are selected in such a way that the cavity resonates at the cut-off frequency and on the .pi. mode. Applications include measuring oscillators and heterodyne radar transmitters and receivers.

Abstract: A voltage controlled oscillator for the conversion of a ratiometric analog signal into a digital signal is disclosed. The oscillator generates a square wave whose frequency is a function of the magnitude of the analog signal input. The variable frequency wave is generated by a comparator receiving high and low threshold levels from a network for comparison with a ramping voltage developed by a timing element. An increasing ramp is provided by a current source whose output is proportional to the analog signal and a decreasing ramp rate is provided by a current sink whose output is similarly proportional to the analog input signal. Because the analog input signal is ratiometric with variations in the power supply voltage, the ramp rates change with these variations, however the high and low threshold levels also change with variations in the supply voltage thereby the comparator generates a square wave output at a frequency independent of these variations.

Abstract: The present invention relates to a backward wave mode oscillator tube, the delay line of which is in two sections of dissimilar length both operating in the backward wave mode, aligned in the direction of propagation of the electrons of the beam, the second being substantially shorter than the first and exhibiting a structure homothetic with the first in the ratio 1/n, n being an integer, with a load arranged at the end of this second section which is adjacent the electron-gun, in which load is picked-up electromagnetic energy on the n.sup.th harmonic of the predominant component of the wave in the first section.

Abstract: A relativistic electron beam device for producing highpower microwave radion. The device comprises an electron beam injection gun, a drift chamber comprising a tube having a plurality of gapped resonant cavities along its length, means for converting the energy-modulated beam and means for extracting rf (microwave) radiation from the density-modulated, relativistic, electron beam.

Abstract: Selectively damped travelling wave tubes having particularly periodically alternating magnetic field for guiding the electron beam comprise a delay line consisting of cells which are separated from each other by partitions and which are positioned one behind the other in the direction of beam travel. At least one resonator chamber is provided with damping material and coupled to at least one of the cells, the resonant frequency of the resonator chamber being at least almost equivalent to a predetermined interference frequency and each of the chamber resonators formed by a recess in a partition and its resonant frequency having the most energetic oscillation corresponding at least approximately to the frequency of an interference mode which is above the operational frequency band.

Abstract: A microwave oscillator is provided having electron emissive means and a first surrounding resonant structure. The first structure is fabricated of a material capable of emitting secondary electrons. A second resonant structure surrounds the secondary electron emitter and microwave energy is generated by the interaction between the electrons and currents induced in the structure. The high degree of isolation between the first oscillator section and the second amplifying section results in the generation of stable oscillations relatively free of effects of load variations.

Abstract: A circuit is provided in a traveling-wave tube package which eliminates the need of manually setting the power supply voltage to match the proper operating voltage of the tube. The circuit utilized within the traveling-wave tube package forms a part of the power supply, the remainder of which is provided externally of the traveling-wave tube package. By selecting the proper circuit components, the traveling-wave tube package can be connected without adjustment to a power supply and still operates at the desired voltage.