Abstract: A radio frequency (RF) transmission line is described. The RF transmission line includes a first ground line, a second ground line, and a signal line disposed on a substrate and forming a coplanar waveguide. A plasma limiter feature is integrated into an internal surface of one or more of the first ground line, the second ground line, and the signal line. The plasma limiter decreases a gap distance between the signal line and the associated ground line. The gap distance is selected, together with a gas pressure, to control a voltage at which the gas within the gap breaks down, targeted at a breakdown power of 1 W across a wide bandwidth. The plasma limiter thus limits a power transmitted by way of the RF transmission line for protecting a sensitive integrated circuit.

Abstract: A magnetic field propulsion unit includes a magnetic field generating device with multiple conductive lines conduct a current to generate a magnetic field; a contact breaker arrangement individually transitions each of the multiple conductive lines from a conductive state to a non-conductive state; an energy supply unit provides the magnetic field generating device with electrical energy; and a control unit controls the energy supply unit so that energy supply to each individual conductive line is controlled and control the contact breaker arrangement. The multiple conductive lines are arranged along a longitudinal axis. The control unit supplies a first conductive line with electrical energy so that a first magnetic field surrounding the first conductive line is generated, transitions the first conductive line to a non-conductive state, and supplies a second conductive line with electrical energy so that a second magnetic field is generated.

Abstract: In an endoscope (1), two optical paths (3, 4) for stereoscopic vision are formed, wherein each optical path (3, 4) is lead from the inside to an interface (16, 19) with an optically more dense material (14) in relation to the surroundings (13) at a point of incidence (22, 25), wherein each optical path (3, 4) can be opened and interrupted by modifying the reflection behavior at the respective point of incidence (22, 25).

Abstract: A receiver for an ultra wideband (UWB) pulse radar system includes a programmable gain network (PGN) block coupled to process a received UWB radar signal. The programmable PGN block includes programmable attenuator having an output coupled to an input node of a UWB low noise amplifier (LNA), and a fast acting power limiter is between the input node and a system ground and/or a power supply node for the radar system. A sampling unit is coupled between an output of the LNA and a processor. The processor implements an attenuation algorithm, wherein the processor is coupled to the programmable attenuator, and provides attenuation control signals to dynamically control a gain or attenuation of the programmable attenuator, such as based on a distance from a transmitting antenna to the product material.

Abstract: A pulsed radar method of sensing or measuring a product material in a storage tank. A plurality of waveform types are automatically selected based on a power limitation. The pulsed radar signal is transmitted by a programmable transmitter to the product material, wherein the pulsed radar signal is reflected or scattered by the product material to provide a radar signal during an interval of time including a target signal. An initial gain or attenuation is automatically set for a programmable receiver. The programmable receiver receives the radar signal including the target signal during the interval of time, and the target signal is signal processed using a lower attenuation setting as compared to the initial gain or attenuation to determine at least one parameter associated with the product material. The transmitted and received radar signal can also be adjusted according to the measured SNR.

Abstract: The present invention discloses an apparatus comprising an enclosure (10) suitable for forming a vacuum therein and means for at least partially suppressing the multipacting effect when a RF or microwave electromagnetic field is generated in said vacuum. In the apparatus, the means for at least partially suppressing the multipacting effect comprises means (12) for passively generating a locally varying magnetic field (16) in the vicinity of at least a portion of the inner surface of said enclosure.

Abstract: According to one embodiment, a radio device comprises a differential antenna that has a pair of differential power supply terminals, a transmitter that transmits a first signal via the differential antenna, a receiver that has a pair of differential input terminals and receives a second signal via the differential antenna, a first control unit, and a second control unit. The first control unit causes a signal conduction state between the differential antenna and the receiver when the receiver receives the second signal. The second control unit switches from a signal conduction state to a signal block state between one of the differential input terminals and one of the differential power supply terminals based on a reception state when the receiver receives the second signal.

Abstract: A microwave generator has a resonator with two mutually spaced resonator electrodes. The resonator electrodes provide a spark gap device which breaks down upon the application of a firing voltage between them. The spark gap device has at least two parallel-connected spark gaps.

Abstract: A microwave generator includes a resonator which has two mutually opposite resonator electrodes formed with a spark gap device that breaks down when an ignition voltage is applied. In order to provide the microwave generator with increased power, in which the resonator can be operated at relatively high ignition voltages or field strengths, the spark gap device has at least two spark gaps connected in series.

Abstract: A microwave generator has at least one resonator with two mutually opposite resonator electrodes which are separated by a spark gap. The spark gap breaks down when a high-voltage is applied. The resonator electrodes are designed in the area of the spark gap such that they result in a two-dimensional or three-dimensional section with a substantially constant, minimum electrode separation.

Abstract: A device for coupling an input signal to an output signal includes a metal transmission line; an ultra-small resonant receiver structure operatively connected to an end of the transmission line constructed and adapted receive the input signal and to cause at least part of the input signal to be passed along the transmission line in the form of plasmons; an ultra-small resonant transmitter structure operatively connected to another end of the transmission line and constructed and adapted to receive at least some of the plasmons corresponding to the input signal on the transmission line and to transmit the received signal as an output signal; a source of charged particles constructed and adapted to deliver a beam of charged particles along a path adjacent the ultra-small resonant receiver structure, wherein the input signal is encoded in the beam of charged particles; and a detector mechanism constructed and adapted to detect the output signal from the ultra-small resonant transmitter structure and to provide a

Abstract: Microwave routing elements and methods of directing microwaves are disclosed. One routing element comprises an inlet region, a plurality of outlet regions, and junctures positioned between an associated outlet region and the inlet region. Each juncture includes electrodes configured for generating an electrical arc across the juncture to inhibit transmission of microwave energy when the arc is present and permit passage of the microwave energy when the arc is absent. Another routing element includes the inlet region, the outlet regions, and partitions positioned between an associated outlet region and the inlet region. Each partition includes apertures and each aperture includes electrodes configured for generating an electrical arc across the aperture to inhibit transmission of microwave energy when the arc is present and permit passage of microwave energy when the arc is absent. Systems including the routing element, a microwave source, and a plurality of microwave processing chambers are also disclosed.

Abstract: A dual-channel passband filtering system having a first, second and third balanced ports for connecting, respectively, to a first transceiver, an antenna and a second transceiver. A first lattice-type passband filter is connected between the first and the second port, and a second lattice-type passband filter is connected between the second and the third port. A phase shifter is used to match the first and second transceiver and the second port. A balun can be used for each port to convert the balanced port to a single-ended port. In each passband filter, two series resonators are use to provide two balanced ends, and two shunt resonators are connected to the series resonators in a crisscross fashion to form a differential or balanced topology. The first and second passband filters have different frequencies.

Abstract: This invention is a modular active filter that can be inserted between the antenna and a filter of a pre-existing unit, so that it can still function normally, without noise from cellular phones. This unit is modular. A heterodyning unit is used with a prefilter/amplifier unit and a post-filter/amplifier unit. After down converting the signal, while heterodyning, the signal is put through at least one crystal filter to filter out the noise introduced by cellular phones. To make sure that the unit works well with a wide variety of antenna-receiver pairs, the resonant frequency of the filters of the pre and post amplifier/filter units is set to the center frequency that the antenna and receiver are designed to handle. In this way, only one type of unit needs to be manufactured for each frequency band. An example of such an operating frequency might be 900 MHz. This invention has two types of embodiments. In one type embodiment the local oscillator produces only one fixed frequency.

Abstract: The present invention provides a diode limiter device in which a first penetration hole is formed on a wall surface of an H surface; the PIN diode is supported by the PIN diode mounting side of the post with the PIN diode being electrically connected to the waveguide at the first penetration hole; a second penetration hole is formed on the other wall surface opposite to the wall surface; a second conductive boss which grasps the PIN diode with the post is electrically insulated and supported with respect to the second penetration hole; a wiring substrate with the detection diode and the resistor mounted thereon is installed; and the wiring substrate is supported in the second penetration hole by a third boss, thereby improving productivity and reducing cost.

Abstract: A method of generating high-power microwaves from a compact source is disclosed by which a transmission line cavity resonator is charged to a high voltage and an electrical switch in the resonator is closed very quickly to produce subnanosecond current risetime and a resultant high-power microwave pulse. Structure to accomplish the method is also disclosed.

Abstract: A receiver protector device includes a sealed discharge chamber containing one or more pairs of spaced-apart, conical electrodes and an ionizable gas. A field emission array is mounted in the discharge chamber to provide a source of free electrons which assist in initiating a discharge when an RF input signal exceeds a desired threshold power level. The field emission array includes a substrate, a plurality of generally conical emitters distributed on the substrate, a conductive gate layer for extracting electrons from the emitters and a dielectric layer between the gate layer and the substrate. When a bias voltage is applied to the gate layer, electrons are extracted from the emitters. The field emission array can be mounted adjacent to the electrodes or in a recess in one of the electrodes. The bias voltage can be supplied by a battery mounted on the receiver protector device external to the discharge chamber.

Abstract: A microwave resonant cavity for a spectroscopic light source includes a housing having therein a chamber formed by side walls and a cylindrical outer wall. The side walls having aligned openings therethrough which are on the longitudinal axis of the outer wall. A refractory tube which is adapted to contain a gaseous plasma extends through the aligned openings and across the chamber in the housing. The portion of the side walls of the chamber adjacent the openings are closer together than the remaining portions of the side walls so that the chamber has a first portion around the refractory tube which is narrower than a second portion of the chamber around the first portion. A coupling loop is electrically coupled to a side wall of the chamber within the second portion of the chamber and is connector to a coaxial connector which extends through the outer wall of the housing to deliver microwave power to the chamber.

Abstract: A passive, broadband, millimeter wave, fin-line, gas discharge device operable for use in a radar system as a receiver protector. The preferred embodiment of this device comprises: a rectangular waveguide housing having a free electron emitting radioactive primer mounted upon one interior wall, an inert gas under pressure contained within the housing by two thin, low loss dielectric windows at opposing ends of the waveguide housing, and two bevelled, tapered fins operable to provide a narrow discharge gap region. Incident ratio frequency signals entering the radar system pass through the fin-line receiver protector. Signals entering the waveguide housing through the thin dielectric windows excite the free electrons causing the electrons to collide with the inert gas molecules. A spontaneous breakdown of gas occurring in the narrow discharge gap region between the two bevelled, tapered fins greatly attenuates the incident ratio frequency signal from entering the receiver thereby protecting it.

Abstract: A spark gap apparatus triggerable by application of a microwave pulse. The apparatus includes a first electrode including a microwave waveguide, and a second electrode spaced from the first electrode. A microwave generator is connected to supply microwave pulses to the waveguide. A main current circuit to be switched is connected to the electrodes. The first and second electrodes include components for causing the simultaneous existence of a number of spark channels therebetween in response to coupling of a microwave pulse to the waveguide so that coupling of the pulse to the waveguide results in switching of the main current circuit. A method of using the spark gap apparatus is also disclosed.

Abstract: The disclosed multipactor device has a waveguide bandpass filter structure including a plurality of spaced pairs of opposing electrodes defining respective gaps therebetween in which multipactor action can occur in response to input microwave power in excess of a predetermined level. A radioactive source of beta particles provides electrons within the bandpass filter structure to ensure a very rapid commencement of multipactor action. The radioactive source includes a disk coated with a tritium compound and mounted in a transverse bore adjacent to the bandpass filter structure.

Abstract: A radar system having a common antenna for transmitting and receiving signals conventionally includes a branch duplexer which is bulky and inconvenient.By using a waveguide section having an antenna port at one end and a receiver port at the other, and including a protection unit comprising p.i.n. diodes these difficulties are reduced. The diodes prevent transmitted energy from a magnetron reaching the receiver port but allow received energy, because of its lower amplitude, to pass.

Abstract: A microwave gas discharge apparatus for use as a limiter or TR device or the like and employing a primary discharge arrangement which has a single resonator used for priming the discharge device and determining the priming energy frequency.

Abstract: A capacitor discharge apparatus of the kind having a spark gap device for discharging a capacitor to provide a current impulse for conduction through a load. The capacitor and spark gap device both include flat terminals for connecting them directly to a foil strip transmission line. The capacitor is relatively thin and configured such that electrical current flows through it along a short, substantially uni-directional path. The current path of the apparatus is configured such that it retraces itself in a closely-spaced relationship, whereby the magnetic field created by current flowing through each segment of the path is substantially canceled by the magnetic field of the oppositely-directed current flowing through the corresponding, closely-spaced path segment. This substantially reduces the apparatus' inductance, such that it provides an increased peak electrical current and a faster current rise time.

Abstract: A high power halogen-filled vial stage receiver protector utilizing an RF priming source in conjunction with a pair of circular guides to provide a continuous supply of priming free electrons to the halogen gas-filled plasma limiter vial.

Abstract: A high-repetition rate switch for delivering short duration, high-power electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

Abstract: The plasma switching stage of a radar receiver protector is simplified and improved by the utilization of a halogen gas filled quartz container and a "keepalive" electron source. The container is configured as a capillary stem filled with low pressure chlorine gas and provides the active switching element in the signal waveguide portion of the receiver protector. An enclosed r.f. energy source in combination with the capillary stem creates a copious and steady free electron supply. The r.f. exciting field used to activate the "keepalive" plasma is enhanced by a coaxial re-entrant cavity located on the top wall of the receiver protector waveguide.

Abstract: A coaxial high voltage, high current switch having a solid cylindrical cold cathode coaxially surrounded by a thin hollow cylindrical inner electrode and a larger hollow cylindrical outer electrode. A high voltage trigger between the cathode and the inner electrode causes electrons to be emitted from the cathode and flow to the inner electrode preferably through a vacuum. Some of the electrons penetrate the inner electrode and cause a volumetric discharge in the gas (which may be merely air) between the inner and outer electrodes. The discharge provides a low impedance path between a high voltage charge placed on the outer electrode and a load (which may be a high power laser) coupled to the inner electrode. For high repetition rate the gas between the inner and outer electrodes may be continuously exchanged or refreshed under pressure.

Abstract: A multipactor discharge tuned resonant cavity device, e.g. a magnetron, is irradiated with X-rays in order to assist the starting of the multipactor discharge. The X-rays are produced by electrons striking the surface of the magnetron anode.

Abstract: An iris for a stage of a receiver protector is described incorporating a metal plate having a slot opening wherein the electric field across the slot opening is enhanced by tapering or beveling the edges of the slot.The invention overcomes the problem of high firing threshold and high recovery time of a gas plasma by providing metal in close proximity to the gap for providing free electrons.

Abstract: A receiver protector is described incorporating a waveguide containing several isolation stages followed by at least one iris plate filter.The invention overcomes the problem of RF or microwave leakage power of out-of-band frequencies some of which may be generated by non-linear elements in the prior isolation stages of the receiver protector.

Abstract: Microwave energy is coupled into an elongate waveguide having a rectangular ain cavity with a lateral branch forming a T section. An intense beam of electrons is generated in the rectangular cavity at a particular location relative to the T to reflect incident microwave energy and produce a standing wave. Quarter wavelength spacing of the beam from the T positions either a wave node or antinode at the T. Preferably, in its `open` state, accumulated microwave energy is released as a high power output pulse by establishing an antinode at the T. Alternatively, a node at the T produces a normally `closed` state. In all arrangements, the beam of electrons, which traverses the central portion of the narrow dimension of the rectangular cavity in a direction parallel to the electrical field of its microwave energy, is of sufficient electron density to assure the desired reflection and produce the interference pattern.

Abstract: A microwave discharge gap receiver protector includes a radioactive ignitor of the nuclear decay type to provide an auxiliary source of electron priming therefore, the radioactive ignitor comprising a radioactive plate for emitting beta particles therefrom, and a tubular enclosure to channel the flow of emitted beta particles therethrough. In operation, a portion of the channeled emitted beta particles collide with the inner walls of the enclosure which are comprised of a material having a high secondary emission characteristic to generate additional electron particles as a result of secondary emission. Another portion of the beta particles in the channel of the tubular enclosure collide with existing gas particles to generate a second source of auxiliary electrons. The combined sources of auxiliary electrons result in an increased particle concentration which is emitted at an exit end of the enclosure and directed to the discharge gap of the receiver for priming purposes.

Abstract: PIN diodes of decreasing base region thicknesses, wherein the thickest base region diode functions as a quasi-active limiter with turn-on bias supplied by detected RF current in a Schottky barrier diode with a discharge resistor providing fast recovery; and the thinnest base region PIN diode being a zero bias punch-through type, with a dc sensitivity time control, functioning as a passive limiter during transmit and controlled attenuator during receive provides an improved radar receiver protector circuit. The operation of the PIN diode is enhanced by a unique mounting on a gold-plated copper puck in the circuit board and tuning the signal leads to the diode.

Abstract: High power, phase coherent pulses are generated by superconducting appara which includes a superconducting cavity resonator that is pumped by a low power microwave source while being isolated from a load. Switching of the cavity to an emitting mode is accomplished in 5 to 10 nanoseconds by firing a gas discharge tube that acts to couple the activity to the load while decoupling it from the pumping source.

Abstract: The passive receiver protector, AGC attenuator and sensitivity time control functions of a radar are combined in a single device which performs the functions in front of the radar low noise amplifier with relatively low loss. The receiver protector utilizes semiconductor diodes which operate as a power limiter during transmit and as precision attenuators during receive.

Abstract: A high power pre-TR switch utilizes hot pressed boron nitride to form a vial. The vial contains a halogen gas such as chlorine.

Abstract: A high peak power microwave generator is disclosed in which a plurality of transmission lines are connected to an output wave guide at predetermined intervals along the direction of propagation. Each transmission line is periodically charged, and this electromagnetic energy is released into the wave guide upon the actuation of a light activated silicon switch (LASS) diode connected to the transmission line. The LASS diodes are actuated simultaneously by a laser beam which traverses equal optical paths to each switch. The coincident switching of the transmission lines enables the power in each line to be additive in the wave guide, and much higher output pulses can be obtained. Further, the high speed switching capabilities afforded by the LASS diodes means that the resulting high power can be obtained at a much higher frequency.

Abstract: A pre-TR high power/intermediate power stage apparatus for receiver protectors utilizing a single quartz vial filled with a halogen gas and having a predetermined configuration to provide the dual function of a high power pre-TR and the intermediate power stage.

Abstract: In a vane type magnetron oscillator a resonant co-axial transmission line breaks through the wall of the anode block to couple to two adjacent cavities on either side of a vane. Positioned at a point at which a high radio frequency voltage appears in operation approximately an odd multiple of a quarter wavelength (preferably 3.lambda./4) from the end of the transmission line adjacent the cavities is a multipactor discharge arrangement. This latter consists of two co-axial cylinders one connected to the inner conductor and the other to the outer conductor of said transmission line. The transmission line extends beyond the multipactor discharge arrangement to a total length approximately half wavelength or a multiple thereof and is short circuited at its end.

Abstract: A multipactor discharge tuned resonant cavity device, e.g. a magnetron, is arranged with two multipactor discharge electrodes so that in a discharge condition a net current flows from one electrode to the other. The net current is used to create a self-bias voltage on one of the electrodes which affects the operating frequency of the device.

Abstract: A radio frequency pulse generator capable of providing high energy pulses having an in-line construction includes an annularly shaped spark gap. The input voltage is connected to the resonant element through a central aperture provided in the spark gap rings for high efficiency operation.

Abstract: A tunable frequency pulse generator capable of providing high energy pulses having an in-line construction includes an annularly shaped spark gap and a movable insulator support which includes a conductive sleeve that varies the resonant frequency of the generator. The input voltage is connected to the resonant element through a central aperture provided in the spark gap rings for high efficiency operation.

Abstract: A liquid dielectric radio frequency pulse generator capable of providing high energy pulses having an in-line construction includes an annularly shaped spark gap immersed in an aprotic liquid such as molten sulfur, sulfur monochloride or mixtures thereof. The input voltage is connected to the resonant element through a central aperture provided in the spark gap rings for high efficiency operation.

Abstract: The subject of the invention is a waveguide-type, multi-stage, receiver protector. It combines the use of all-chlorine gas discharge stages and a radioactive primer discharge stage having a semi-inert gas medium in a way to retain the protection benefits of the radioactive primer device, while providing the fast recovery time of the chlorine stages. The apparatus includes an r.f. limiting diode section which aids in attaining the combined benefits of the other two types of stages.

Abstract: A high power duplexer in the millimeter region includes a beam excited plasma switch in combination with colinear waveguide transmission lines. The beam passes through four sets of slots which are positioned in the four narrow adjoining walls of the colinear waveguide transmission lines. A quasi-anode is used to aid in turn-on of the plasma switch.

Abstract: A co-axial line to waveguide junction is formed from a length of waveguide with a co-axial line section along the length with the center conductor of the co-axial line entering the interior of the waveguide length. Connecting means are provided at each end of the length to enable connection of selectably short circuiting means. When any of the short circuiting means is in the short circuited state, a path is created between the co-axial line section and the other end of the waveguide length.