Abstract: Embodiments of the microwave amplification system are described. In an embodiment, a microwave amplification system includes a microwave amplifier that contains a paramagnetic material with an impurity. The impurity has a plurality of nuclear spin and electron spin-based energy levels. The system includes an input to receive a pumping signal which is transmitted to the microwave amplifier to cause a population inversion in the impurity and excite it to one of the nuclear spin and electron spin-based energy levels. The system further includes another input to receive an input signal to be amplified by the microwave amplifier, the input signal having a lower power than the pumping signal. Once transmitted to the microwave amplifier, the input signal is amplified by the excited state of the impurity in the microwave amplifier thereby generating an amplified signal.

Abstract: A new spectral measurement technique is provided which enables measurement even if the light to be measured exists for a very short period. In one embodiment, a broadband pulsed light wave whose wavelength shifts temporally and continuously in a pulse interferes with a light wave to be measured. The intensity at each wavelength of the light wave to be measured is obtained using a Fourier transform of the output signal from a detector that has detected the intensity of the wave resulting from the interference. A laser beam from a laser source is converted to a supercontinuum wave by a nonlinear optical element, and a pulse extension element extends pulses of the supercontinuum wave, thus generating the broadband pulsed light wave.

Abstract: A radiation sensor apparatus for determining a position and/or power of a radiation beam, the radiation sensor apparatus including a chamber to contain a gas, one or more sensors, and a processor. The chamber has a first opening and a second opening such that a radiation beam can enter the chamber through the first opening, propagate through the chamber generally along an axis, and exit the chamber through the second opening. Each of the one or more sensors is arranged to receive and detect radiation emitted from a region of the chamber around the axis. The processor is operable to use the radiation detected by the one or more sensors to determine a position and/or power of the radiation beam.

Abstract: A clock apparatus with a gas cell. The gas cell includes: (i) a first chamber including a sealed interior for providing a signal waveguide; and (ii) a second chamber, in fluid communication with the first chamber, and comprising apparatus for directing atoms having a selected velocity vector into the first chamber.

Abstract: A defense device for combating an unmanned aircraft includes a communications device configured for receiving communications information transmitted by at least one external signal source, an emitting device configured for producing and emitting a high-energy electromagnetic pulse in the event of triggering of the emitting device, and a control device configured to trigger the emission of the high-energy electromagnetic pulse depending on communications information received by the communications device. A protective configuration for combating an unmanned aircraft and a method for operating a protective configuration are also provided.

Abstract: A clock apparatus with: (i) a gas cell, including a continuous path cavity including a sealed interior for providing a signal waveguide; (ii) an apparatus for providing an electromagnetic wave to travel along the continuous path cavity and for circulating around the continuous path cavity back toward and past a point of entry of the electromagnetic wave in the continuous path cavity; (iii) a dipolar gas inside the sealed interior of the cavity; and (iv) receiving apparatus for detecting an amount of energy in the electromagnetic wave, wherein the amount of energy is responsive to an amount of absorption of the electromagnetic wave as the electromagnetic wave passes through the dipolar gas.

Abstract: A maser assembly includes a pump light source; a maser material including molecules that are excited through the absorption of light (1) from the pump light source, and which subsequently transfer via intersystem crossing (9) into the sublevels of their triplet ground states, so causing a population inversion between two sublevels (16,18); an electromagnetic structure in which the masing material is disposed, and which supports a microwave mode that is both resonant in frequency with and magnetically coupled to the transition between these two sublevels; and where energy is supplied to the microwave mode through stimulated emission (25) across the transition at such a rate as to exceed the mode's electromagnetic losses, the microwave mode being a maser mode. The assembly includes provisions for effecting substantially continuous maser activity during operation of the assembly.

Abstract: The invention relates to heat power engineering, in particular, to methods that use a working medium for producing useful work from heat of an external source. The method comprises interaction of the working medium with an energy source and interaction of the working medium with an additional low-temperature energy source in the form of the positron state of the Dirac's matter by means of bringing the working medium into quantum-mechanical resonance with said state. The quantum-mechanical resonance is initiated by changing at least one of the thermodynamic parameters of the working medium, while the value of spontaneous fluctuations of the variable parameter in the vicinity of the line of absolute instability in the state diagram of the working medium is predetermined, and the change step for the thermodynamic parameter is set to be lower than the predetermined value of said fluctuations.

Abstract: Optically pumped masers are described. The devices are useful for microwave amplification, microwave phase shifting and microwave limiting function. The devices are based on electron spin polarization of a stable free radical species induced by an intermolecular energy transfer process acting via a photo induced radical-triplet pair mechanism. A paramagnetic triplet precursor chromophore in a matrix with the stable free radical species is irradiated, preferably using a pulsed laser to initiate the process with concomitant increase in matrix magnetic susceptibility. Microwave radiation incident on the photo activated matrix is reflected as amplified, phase shifted or limited microwave fields dependent on relevant device parameters and on the power of the incident microwave radiation.

Abstract: An amplified broadband optical signal is produced in a transmission system. An optical signal is divided into a first beam and a second beam. The first beam has a wavelength less than a predetermined wavelength. The second beam has a wavelength greater than the predetermined wavelength. The first beam is directed to a transmission link in the transmission system. The transmission system includes a distributed Raman amplifier. The distributed Raman amplifier operates in the wavelength range less than 1480 nm. The second beam is directed to a second amplifier. The first and second beams are combined. An amplified broadband optical signal is produced.

Abstract: A folded waveguide gyrotron-traveling-wave-amplifier comprises: an electron gun for transmitting an axis-encircling beam of electrons with large transverse energy along a first path having an axis; an RF source for producing and applying in a second path an RF input millimeter wave signal having a bandwidth in a preselected frequency domain and having a transverse electric field; a source for generating a solenoid magnetic field parallel to the axis along the first path; a beam collector; and an interaction circuit such as an H-plane bend serpentine waveguide positioned within the solenoid magnetic field and having a narrow wall containing a beam tunnel hole for passing the axis-encircling beam of electrons therethrough to the beam collector, an output end, and an input end for receiving and passing the RF input millimeter wave signal through the H-plane bend serpentine waveguide to the output end to modulate the axis-encircling electron beam, the modulated axis-encircling electron beam amplifying the RF inpu

Abstract: A method of generating microwave power by producing a charged-particle beam that is charge-neutralized by electrons. The charged particles are heavier than electrons. The charge-neutralized beam is passed through at least one conductive cavity which is resonant at a desired microwave frequency and in a desired fundamental mode. A microwave beam is extracted from said resonant cavity.

Abstract: A double beam cyclotron maser comprising two electron guns for introducing two electron beams traveling parallel to each other at different speeds into an electron drift tube/waveguide. The beams have respectively different electron cyclotron space-charge harmonics. A solenoid maintains a magnetic field parallel to the direction of propagation of the electron beams while a magnetic wiggler field initially imparts a transverse force to the electrons such that they propagate down the drift tube with a helical gyration. The magnetic fields, electron beam velocities, and beam space charge harmonics are adjustable to set the interaction frequency at which amplification of electromagnetic radiation can occur. The waveguide is a slow wave structure so configured as to slow the signal from the magnetron to match the phase velocity of the double stream cyclotron space-charge wave.

Abstract: Novel microwave processing equipment includes a silicon single crystal containing neutral {110} planar four vacancies, a cooling mechanism for holding the silicon single crystal to a low temperature, a light pumping mechanism for irradiating light to the silicon single crystal, a magnetic field applying device for applying a static magnetic field to the silicon single crystal, an orientation holding mechanism for holding the silicon single crystal to a specific orientation with respect to the static magnetic field, an electromagnetic wave inputting mechanism for supplying an input electromagnetic wave to the silicon single crystal, and an electromagnetic wave outputting mechanism for extracting an output electromagnetic wave from the silicon single crystal.

Abstract: An active optical fibre star coupler having a length of amplifying optical fibre (1) optically connected at one end to a wavelength combining coupler (2) and at the other end to via a beam expanding element (3) to a set of output optical fibres.

Abstract: A traveling wave type amplifier. The device features a pair of short helical input and output couplers through which an electron beam is projected. Application of an RF signal to the couplers serves to modulate the electron beam. A drift tube to be positioned between the couplers is dimensioned to attenuate the RF signal while permitting the modulated electron beam to pass through. An amplified output signal is extracted from the output helix. Gain of the tube is enhanced by a linearly decreasing magnetic focussing field.

Abstract: An ultra-stable superconducting triple cavity ruby maser oscillator (10) is obtained by providing the oscillator with a superconducting quantum interference device (SQUID) (50), which measures the magnetic field at the ruby (14) and compensates for changes by adjusting the RF pump signal amplitude (42), thereby attaining stabilities of about four orders of magnitude greater than presently attainable.

Abstract: A plasma-filled waveguide acts as a dispersive element for pulse compression or power multiplication of a frequency chirped microwave signal. In one embodiment, the frequency of the source is chirped near a plasma resonance while the plasma waveguide is held contant in time. In a second embodiment, the source frequency is held fixed while the plasma filled waveguide parameters are varied in time in the vicinity of a plasma resonance.

Abstract: A fiber optic amplifier utilizes a crystal fiber of laser material to bidirectionally amplify light signals. This amplifier permits the application of both pumping illumination and the signal to be amplified to the end of the crystal fiber to avoid the disadvantages inherent in side pumping this fiber. End pumping is accomplished by taking advantage of the slow spontaneous fluorescence of the laser crystal to sequentially apply the pumping illumination and then the signal to be amplified to the crystal. This sequential application of signals is made possible through the use of a switchable coupler which allows light to be selectively coupled from either of a pair of input optical fibers to a single output optical fiber which is coupled to the crystal fiber. The pumping illumination is initially supplied to the crystal fiber to invert the ions within the crystal.

Abstract: A high power amplifier for amplifying millimeter-wave radiation comprising: a length of metallic waveguide tapered from a small cross-sectional end to a larger cross-sectional end; a magnetron-type electron injection gun for injecting a spiral beam of relativistic electrons at the small end of the waveguide for propagation axially therein so that the wall radius of the tapered waveguide increases in the downstream direction of the electron beam; an input coupler for launching electromagnetic waves to be amplified into the waveguide at the large waveguide end thereof such that the individual frequencies in the input waves are reflected at various points along the constriction of the waveguide taper so that they copropagate with and are amplified by the electron beam; and a magnetic circuit for generating an axial magnetic field within the tapered waveguide with a unique profile approximately in accordance with the following equation to maintain synchronism: ##EQU1## where the z subscript is the waveguide axial

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 defense system wherein a radar intercepts and follows a target and includes an antenna array and a low level source of microwave energy for exciting the elements of the array to produce radar returns and define the path. A microwave storage reservoir is supplied upon demand with high energy microwave energy and is coupled to microwave feed channels leading to the elements of the antenna array. Microwave dump switches at the juncture of the channels and the reservoir control flow of energy from the reservoir. Control means responsive at least in part to the presence of returns periodically actuate the dump switches for flow of microwave energy from the reservoir to the target via the antenna array.

Abstract: A cyclotron maser microwave amplifier and oscillator which utilizes non-relativistic electrons in cyclotron motion and a spatially nonlinear electrostatic field which is produced by the space charge of the electrons. The term "spatially nonlinear electrostatic field" encompasses static electric fields whose magnitude can be described mathematically as varying in a nonlinear manner as a function of position in one or more directions. As taught by U.S. Pat. No. 4,253,068 of Feb. 24, 1981, "Cyclotron Maser Using a Spatially Nonlinear Electrostatic Field", completely non-relativistic electrons may be used in principle for which phase bunching will occur due to the nonlinear motions induced by the electrostatic field, resulting in stimulated emission of cyclotron radiation for use in a microwave amplifier or oscillator. U.S. Pat. No. 4,253,068 teaches that appropriate nonlinear electrostatic fields can be established by suitably shaped electrodes and a low charge density electron beam.

Abstract: An isolator is described for use in a low-noise maser amplifier, which provides low loss across a wide bandwidth and which can be constructed at moderate cost. The isolator (40) includes a train of garnet or ferrite elements (50, 52) extending along the length of a microwave channel (14) parallel to the slow-wave structure (24), with the elements being of staggered height, so that the thin elements (50) which are resonant to the microwaves are separated by much thicker elements (52). The thick garnet or ferrite elements reduce the magnetic flux passing through the thin elements (50), to permit altering of the shape of the thin elements so as to facilitate their fabrication and to provide better isolation with reduced loss, by increasing the thickness (T) of the thin elements and decreasing their length (L) and width (W).

Abstract: An electron cyclotron maser high-frequency generator/amplifier having a cavity resonator positioned in an axial magnetic field. A spiralling beam of relativistic electrons is injected into the cavity and stimulated emission of radiation by the electrons takes place at the frequency of a wave mode supported by the cavity resonator. The transverse efficiency, defined as the average electron energy loss divided by its initial transverse energy, is maximized by disposing a shaped iron collar about the cavity resonator to provide an axial magnetic field in the cavity resonator whose amplitude increases in the beam direction-of-travel. In an alternative embodiment, the transverse efficiency is maximized by tapering the inner wall of the cavity in the axial direction to provide a wave-mode in the cavity resonator whose electric-field amplitude increases in the beam direction-of-travel.

Abstract: A cyclotron maser microwave amplifier or oscillator which utilizes non-relativistic electrons (or other charged particles) in cyclotron motion and a spatially nonlinear electrostatic field. The term "spatially nonlinear electrostatic field" encompasses static electric fields whose magnitude can be described mathematically as varying in a nonlinear manner as a function of position in one or more directions. Completely non-relativistic electrons of very low energy may be used in principle for which phase bunching will occur due to the nonlinear motions (induced by the electrostatic field) resulting in stimulated emission of cyclotron radiation for use in the amplifier or oscillator. This is in complete contrast to the relativistic cyclotron maser (Hirschfield, U.S. Pat. No. 3,398,376) which required the electrons to be acting under the relativistic effect of the electron mass (and hence cyclotron frequency) being a function of its energy to produce the necessary phase bunching and resulting stimulated emission.

Abstract: An apparatus for amplifying coherent radiation at millimeter and submillimeter wavelengths includes the combination of a travelling-wave-tube cyclotron-maser-amplifier structure and a magnetron-injection electron gun. The amplifier structure includes a fast-wave drift tube and an electromagnetic wave launcher within the bore of a superconducting magnet. The magnetron-injection electron gun is also within the bore of the magnet and is coupled to the drift tube. As a travelling wave is launched in a preferred mode in the drift tube, the electron gun injects an annular beam of relativistic electrons having both large energy transverse to the axis of the device and small energy spread into the drift tube so that the electrons gyrate at their cyclotron frequency in orbits about the lines of the axial magnetic field produced by the magnet. The travelling wave is amplified by extracting energy from the relativistic electron beam.

Abstract: An improved getter for a hydrogen maser comprised of screened particles of zirconium-aluminum alloy. One or more pump bodies are connected with a hydrogen maser and each pump body contains a quantity of Zr-Al alloy particles. One or more screens are provided in a passageway connecting a pump body with a maser to allow passage of hydrogen into the pump body but preventing, in a zero-g environment, the alloy particles from leaving the pump body. The Zr-Al alloy particles are activated by heating.

Abstract: A dielectrically loaded four-port waveguide circulator is used with a reflected-wave maser connected to a second port between first and third ports to form one of a plurality of cascaded maser waveguide structures. The fourth port is connected to a waveguide loaded with microwave energy absorbing material. The third (output signal) port of one maser waveguide structure is connected by a waveguide loaded with dielectric material to the first (input) port of an adjacent maser waveguide structure, and the second port is connected to a reflected-wave maser by a matching transformer which passes the signal to be amplified into and out of the reflected-wavemaser and blocks pumping energy in the reflected-wave maser from entering the circulator. A number of cascaded maser waveguide structures may thus be housed in a relatively small volume of conductive material placed within a cryogenically cooled magnet assembly.

Abstract: An X-band traveling wave maser of the folded-comb type is provided with two figure-eight coils for gain and bandwidth control. One figure-eight coil covers the full length of the comb structure for bandwidth adjustment of an external magnetic field. The other figure-eight coil covers a central half of the comb structure for independent gain adjustment of the external magnetic field. The half of each figure-eight coil at the turn around end of the comb structure is oriented to aid the external magnetic field, and the half of each figure-eight coil at the input-output end of the comb structure is oriented to buck the external magnetic field. The maser is pumped in the push-push mode with two different frequencies.

Abstract: A number of traveling-wave, slow-wave maser structures, containing active maser material but absent the typical ferrite isolators, are immersed in a nonuniform magnetic field. The microwave signal to be amplified is inserted at a circulator which directs the signal to a slow-wave structure. The signal travels through the slow-wave structure, being amplified according to the distance traveled. The end of the slow-wave structure farthest from the circulator is arranged to be a point of maximum reflection of the signal traveling through the slow-wave structure. As a consequence, the signal to be amplified traverses the slow-wave structure again, in the opposite direction (towards the circulator) experiencing amplification equivalent to that achieved by a conventional traveling-wave maser having twice the length. The circulator directs the amplified signal to following like stages of amplification. Isolators are used in between stages to prevent signals from traveling in the wrong direction, between the stages.

Abstract: A gyrotron gun that generates gyrating electron beams in a controllable manner suitable for use in a wide range of gyro-amplifiers and gyro-oscillators is disclosed. The gyrotron comprises first and second means for abruptly changing a magnetic field and which means are positioned between first, second and third field coils. The field coils are operated so as to provide for a desired magnetic field profile that allows for the control of the parameters desired to provide for small-orbit, large-orbit, and linear modes of operation of the gyrotron gun. The gyrotron gun further comprises of a pair of bucking coils arranging near the cathode to independently control the axial velocity spread of the gyrating electron beam.

Abstract: An improved method and structure is disclosed for adjusting the magnetic field generated by a group of electromagnet poles spaced along the path of a charged particle beam to compensate for energy losses in the charged particles which comprises providing more than one winding on at least some of the electromagnet poles; connecting one respective winding on each of several consecutive adjacent electromagnet poles to a first power supply, and the other respective winding on the electromagnet pole to a different power supply in staggered order; and independently adjusting one power supply to independently vary the current in one winding on each electromagnet pole in a group whereby the magnetic field strength of each of a group of electromagnet poles may be changed in smaller increments.