Abstract: A window assembly for transmitting relatively high power microwave energy from a waveguide, held at substantially atmospheric pressure levels, into a microwave reaction chamber at sub-atmospheric pressure levels. The window assembly provides for the transmission of microwave energy to generate a glow discharge plasma without suffering from catastrophic failure as a result of excessive temperature and pressure conditions.

Abstract: A microwave process seal and method is provided for use, for example, in the detection of ullage level and flow in a vessel or conduit by detecting the presence of a solid or liquid material in proximity to a microwave detector. Particularly, a horn design is provided in conjunction with, the microwave process seal of the present invention which fits in the mouth of the horn. The microwave process seal is kept as thin as possible to meet pressure requirements. The surface of the seal is oriented at or near the Brewster angle. The Brewster angle is that angle for which there is total transmission across a dielectric boundary for energy that strikes the boundary with a linear polarization.

Abstract: Disclosed is a microwave window comprising a circular strip mounted in a circular waveguide section connected, on either side, to a rectangular waveguide containing a matching transformer. The diameter of the circular waveguide is smaller than the diagonal of the rectangle. A wall provides for impervious sealing with respect to the exterior between the rectangular waveguide and the circular waveguide section. Each wall is provided with an aperture included in a portion of cross-section common to the rectangular waveguide and to the circular waveguide section. The area of the aperture is smaller than the area of the portion of cross-section. The disclosed device can be applied to wideband power microwave windows with improved mechanical and electrical behavior.

Abstract: A housing (100), that is suitable for use in a automated manufacturing and/or testing environment, is constructed and arranged to substantially enclose and shield a trimmable electrical circuit (107) from radio frequency interference external to the housing (100). At least a portion of the housing (100) is constructed and arranged to shield while contemporaneously allowing a laser beam (114) to pass therethrough so as to focus on at least a portion of the trimmable electrical circuit (107) and thereby laser trim the trimmable electrical circuit (107).

Abstract: A coupling-out window for linearly polarized high-power microwaves exhibits at least one plate transparent to microwaves and cooling fins. The cooling fins are situated together with the plate in a plate plane and are aligned perpendicular to a direction of polarization of the microwaves. They are in heat-conducting and pressure-locking contact with the plate.

Abstract: Dielectric-filled longitudinal slots in the common wall of concentric circular and coaxial dielectric-lined waveguides allow microwave energy to be efficiently coupled therethrough. Such couplers are used with megawatt level gyrotrons for varied applications. One application provides a double seal waveguide vacuum window with low reflections over a wideband of frequencies. Another application provides an output coupler and window for quasi-optical gyrotrons. Still another application provides a waveguide mode converter for converting high order microwave modes, as are commonly found in waveguide cavities of high power gyrotrons, to lower-order modes suitable for low-loss transmission, such as the HE.sub.11 mode.

Abstract: A waveguide is provided which can include a bearing supporting a probe or other equipment for rotation. In order to prevent particles of the waveguide metal or waveguide cleaning materials embedded in the metal from entering the bearing, a window is fitted across the waveguide at a selected position between two waveguide sections or at each of a number of positions, the window being transparent to microwave transmission, being capable of transmitting pressure and being capable of filtering particles of a diameter in excess in 0.005 inch (0.013 cm).

Abstract: An improved apparatus for the formation of a functional deposited film using a microwave plasma chemical vapor deposition process characterized in that a microwave transmissible dielectric material is used for the microwave introducing window, and the window has a structure wherein the dielectric material is divided into blocks of the same or different dielectric materials having a specific inductive capacity of more than 1.0. In this way it is possible to adjust not only the resonant frequency characteristics but also the electromagnetic resonant mode of the window to resonate with the microwave oscillation frequency so as to enhance microwave transmission.

Abstract: The microwave transmission between wave guide regions (a, b) having different internal gas pressures and/or different fill-gas compositions, that is to say, the coupling or outcoupling of microwaves of such a wave guide region into another region is improved in that between the wave guide regions at least a single pumping stage (6, 7, 8, 9) is inserted. The wave guide (1) is connected to the pumping stages preferably via the slots (2, 3, 4, 5) which do not virtually outcouple the microwave power.

Abstract: The disclosure concerns microwave tubes and, more particularly, travelling wave tubes wherein the region under vacuum is isolated from the external HF input/output circuits by vacuum-tight windows. The disclosed window consists of a ceramic cylinder, the two ends of which bear metallic flexible rings. This window is brazed to the cylindrical chamber of the part under vacuum by means of a clearance machined in the chamber, so that the chamber and the window are integrated and coaxial. The HF transmission through the window is achieved by means of an antenna formed by a metallic strip mounted, at right angles, on a metallic cylinder that fits the chamber. The device can be applied to power microwave tubes and, notably, to travelling wave tubes.

Abstract: In a travelling wave tube, the delay line of which is coupled to a transmission line of an external microwave circuit by a coupling pin having a coupling surface that faces an end surface of the transmission line, a microwave window extends between the coupling surface of the coupling pin and the end surface of the transmission line. This window is permeable to the microwave energy and impermeable to the gases. It is fixed imperviously to the travelling wave tube.

Abstract: In a double disk window assembly for a waveguide, first and second dielectric disks face each other and are coupled to waveguide segments, respectively. The second dielectric disk has a central coupling section which is mechanically coupled to the center region of the first dielectric disk. The first and second dielectric disks are sealed to define a gap through which a coolant passes.

Abstract: A window assembly for transmitting relatively high power microwave energy from a waveguide, held at substantially atmospheric pressure levels, into a microwave reaction chamber at sub-atmospheric pressure levels. The window assembly provides for the transmission of microwave energy to generate a glow discharge plasma without suffering from catastrophic failure as a result of excessive temperature and pressure conditions.

Abstract: An improved radio frequency coaxial transmission line vacuum feed-through provided based on the use of a half-wavelength annular dielectric pressure barrier disk, or multiple disks comprising an effective half wavelength structure to eliminate reflections from the barrier surfaces. Gas-tight seals are formed about the outer and inner diameter surfaces of the barrier disk using a sealing technique which generates radial forces sufficient to form seals by forcing the conductor walls against the surfaces of the barrier disks in a manner which does not deform the radii of the inner and outer conductors, thereby preventing enhancement of the electric field at the barrier faces which limits voltage and power handling capabilities of a feedthrough.

Abstract: A fluid-tight coupling device for microwave radiation of high energy incls a tubular dielectric window which is sealingly connected to one end of a waveguide supplying the microwave radiation and forms a continuation of the waveguide. The other end of the tube forming the window is tightly sealed by an essentially conical reflector. The tube forming the window is surrounded on the outside by a cup-shaped waveguide portion. The reflecting surface of the reflector and the reflecting inner surface of the cup-shaped waveguide portion are formed such that the microwave radiation emerging from the waveguide is reflected through the tubular window into the cup-shaped waveguide portion and from the latter to the open end of the waveguide portion in such a manner that an input mode of type TE.sub.mn is transformed into itself or a well-defined adjacent mode TE.sub.m'n', further secondary modes are minimized and at the same time return waves are also minimized.

Abstract: A low noise coaxial microwave window of particular utility in hermetic and high power applications, having a metallic center conductor, a metallic outer support, and a ceramic support brazed between the two conductors. The brazed joints are specially prepared to have a series of layers and sublayers extending from the ceramic to the metal, as follows: ceramic, cermet, cermet-nickel alloy, copper-nickel alloy, copper, braze metal, and metallic piece. The nickel content of the cermet-nickel and copper-nickel alloys is limited so that the alloys are non-magnetic. The nickel-containing alloys assist in bonding the copper layer to the cermet in a reliable, reproducible fashion, but control of the nickel content avoids microwave intermodulation effects. Where the window separates a vacuum from another medium, the surface of the support contacting the vacuum is formed from at least two noncoplanar segments to eliminate the possibility of multipacting. The same techniques are used in waveguide microwave windows.

Abstract: A method of making a microwave semiconductor component and concurrently forming therewith a mounting membrane adapted for positioning the semiconductor component in an RF transmission medium such as a waveguide. Substantially concurrently with the deposition of a metallic film in connection with forming a semiconductor elements, there is deposited a metallic membrane on the base silicon substrate and outside of the circuit element. The outer periphery of the base substrate is removed to expose the membrane. The metallic membrane is preferably of gold.

Abstract: A pressure sealed waveguide to coaxial line connection formed with a low cost, non-pressurizable waveguide to coaxial line adapter, an elastomeric sealing boot, and a specially configured mounting seat on a housing which contains a pressurizable waveguide cavity. The connection provides a low cost alternative to hermetically sealed waveguide to coaxial line adapters.

Abstract: In a microwave apparatus with an air-tight window plate, first and second coaxial waveguide assemblies are coupled to each other so that a coaxial waveguide is formed. The first and second inner conductor sections of the first and second assemblies have first and second metal blocks. The first metal block is fitted in the second metal block by a shinkage fit and the first outer conductor section of the first assembly is air-tightly welded to the second outer conductor section of the second assembly. An RF matching annular groove is defined between the first and second metal blocks.

Abstract: A thin waveguide window having a broad band of operating frequencies is composed of a metallic frame provided with an opening and a leak-tight closure plate of dielectric material. The frame permits a reduction in dimensions of the plate, with the result that any spurious frequencies introduced by the plate are rejected from the operating frequency band. By giving the plate an oblong shape, it is possible to balance its inductive components by means of its capacitive components at the mid-band frequency. A matching transformer formed by the ridges which are more closely spaced in the vicinity of the window than in the remainder of the waveguide permits matching throughout the frequency band.

Abstract: Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

Abstract: A waveguide window contains a central transverse pane of a material with high dielectric constant such as alumina ceramic. The central pane is an integral number of half-wavelengths thick. On each side of the central pane and immediately adjacent it is a side pane of material with relatively low dielectric constant such as fused quartz. The side panes are odd numbers of quarter-wavelengths thick. The dielectric constants of the side panes are preferably the square root of the dielectric constant of the central pane. The improved wave impedance matching provides a low wave reflection over a wide frequency band.

Abstract: The present invention relates to a circular window for an ultra-high frequency waveguide. This window is constituted by a circular plate or wafer made from a dielectric material mounted in a waveguide section, connected on either side of a waveguide operating in a frequency band centered around the central frequency. The diameter of the circular plate is chosen so as to reject the ghost modes outside the frequency band. The length of the circular guide section is chosen so that the reactance of the assembly constituted by the plate and the circular guide is cancelled out for the central frequency. It also comprises a half-wave impedance transformer, whose height is chosen so as to bring about the matching in the operating frequency band. The window associated with rectangular waveguides is more particularly used with tubes for telecommunications.

Abstract: An output section which takes output by a coaxial line from the output cavity of a microwave tube such as a klystron, and has a structure such that the coaxial line is divided into a coaxial line section continuous with the output cavity, and a coaxial line section including a dielectric air-tight ring which is fastened so as to be vacuum-tight between the internal and external conductors, and with the internal and external conductors of these divided coaxial line sections each joined so as to be air-tight by thin weld rings. The output section obtained is easy to manufacture, has high reliability, and is applicable to high power usage.

Abstract: A coupler employing two similar sections of waveguide which extend coliney in longitudinal succession. Adjacent ends of the guide sections are spaced apart to form a gap in the boundary of the sections. A third section of waveguide is disposed external to and coaxial with at least a part of each of the two waveguide sections to provide a boundary surrounding the gap. Electromagnetic energy propagating down one of the two similar sections of waveguide in a first mode and entering the gap is converted partly to a plurality of other modes. The converted energy is reconverted to the first mode upon reaching the other of the two similar sections of waveguide. The electric field pattern exciting the section of waveguide at the end of the gap and propagating down it is exclusively in the first mode.

Abstract: A novel window assembly with improved cooling capabilities for use in high power microwave tube and waveguide apparatus is disclosed. A septum with a circular central aperture is disposed between two parallel windows. Cooling fluid is circulated in from the periphery of one of said windows, flows toward the central region, through the aperture in the septum, and then out at the periphery of the second of said windows. This arrangement results in an increased cooling fluid velocity thereby increasing the cooling effectiveness of the window assembly. By adding surface features such as bumps, channels and the like to the septum, one can additionally increase local cooling fluid velocity in areas of the window assembly subject to greater localized heating. This is particularly useful in gyrotron tubes, where the energy impinging on the window surface is in the circular-electric-field mode and areas of the window surface are known to be subject to greater thermal stress.

Abstract: A calorimetric load for very high microwave power at very high frequencies is formed by a metallic, cylindrical chamber into which the wave-guide carrying the power opens. Inside the metallic cylinder is a coaxial dielectric cylinder, with a space between full of circulating wave-absorbing fluid such as water. The incoming wave may be in a higher-order mode. To make it disperse rapidly into the absorbing fluid, a conical reflector is located inside the dielectric cylinder to reflect the wave outward.

Abstract: A circular waveguide window between two rectangular wave-guides, having increased bandwidth and increased power handling capability. It uses particular window and an impedance matching structures whose dimensions are related in a particular way to the dimensions of the rectangular waveguides.

Abstract: A resonant microwave cavity 2 has a bi-metal end cap 4 or a tri-metal end cap 26. The end caps 4, 26 include irises 10, 28. The end caps are affixed to walls of the cavity 2 in the usual manner. As temperature varies, the end caps or irises expand into or out of the cavity to compensate for the increase or decrease in length of the cavity walls due to variations in temperature. The internal volume of the cavity is maintained substantially constant. When a bi-metal end cap is used, each layer of metal has a different coefficient of expansion. When a tri-metal end cap is used, the center layer has the highest of coefficient of thermal expansion.

Abstract: A microwave window assembly has a ceramic window (12) with a thickness of more than 10 mm, corresponding to a half wavelength of the microwave energy. The window (12) has a metallized side surface and is connected by means of a soldered joint to a frame (11). The frame (11) is constructed in two parts (11A, 11B) which are soldered to respective edge parts (10A, 10B) of the side surface of the window, while the side surface between the two parts (11A, 11B) of the frame is covered with a layer (13) electrically connecting the two frame parts (11A, 11B).

Abstract: A window assembly for a hollow waveguide of circular cross-section, with improved bandwidth and cooling capability for handling high microwave power transmissions over wide frequency ranges, is disclosed. A plate or disc of dielectric of refractive index n.sub.1 extends sealingly across the waveguide and has two parallel faces which exhibit a pattern of corrugations. One of these faces is in contact with a dielectric fluid of refractive index n.sub.2, and means are provided for cooling and circulating the fluid over said one face. Each of the corrugations extends into the fluid a distance proportional to the inverse of the geometric mean of the product of the refractive indices n.sub.1, n.sub.2. In a preferred embodiment, a second plate is included, separated from the first by a region in which said dielectric fluid is circulated, and in which at least both the faces in contact with the fluid are corrugated.

Abstract: The microwave window is inserted in a rectangular waveguide and is constituted by a half-wave impedance transformer, the wavelength considered being such as to correspond to the central frequency F.sub.0 for which the window has been realized; a dielectric plate of small thickness is mounted above the transformer and two inductive shutters are located on each side of the plate. The dimensions of the window components are so determined that in the case of a matched waveguide, the standing-wave ratio of the window is substantially 1 in a frequency band of at least 35% of the central frequency around the central frequency.

Abstract: A passive limiter formed as a wave-guide, in at least one cross-section of the guide, by means of one or more resonating windows in which is shunt-mounted at least head-to-tail one pair of diodes having the same polarity and being disposed in the same plane. One or more such limiters may be contemplated for forming duplexers.

Abstract: A window assembly for ridged waveguide has a slab of dielectric extending clear across the waveguide cross-section. The slab may be perpendicular to the waveguide or cross it at an angle. The waveguide ridge or ridges are notched so that the dielectric slab passes through the notch. Inductive tuning posts may be added to make a broadband match. The window assembly has an excellent match over more than an octave frequency range.

Abstract: A gas-tight, high-frequency permeable window arrangement is provided between the input and output sides of a coaxial line, particularly for traveling wave tubes. The dielectric losses, particularly given high-performance tubes, are held so low that too high a thermal load and, thus, a fracture or, respectively, loss of seal of the window arrangement is avoided. For this purpose, a ceramic hollow cylinder is provided between the coaxial line of the input side and the coaxial line of the output side, the ceramic hollow cylinders surrounding the inner conductor of the coaxial line of the input side in the area of its transition to the coaxial line of the output side as a continuation of the outer conductor of the coaxial line of the input side.

Abstract: A gas-tight, high-frequency permeable window arrangement in a coaxial line, particularly for traveling wave tubes, has a large pass band width as well as being mechanically and thermally stable. For this purpose, a hollow cylinder of dielectric material is provided between the coaxial line on the input side and the coaxial line on the output side, the hollow cylinder surrounding the inner conductor of the coaxial line on the input side and being connected with its one end face to the outer conductor of the coaxial line on the input side and being connected with its other end face to a flange which is arranged between the inner conductors of the coaxial lines of the input and output sides. A window arrangement constructed in accordance with the present invention is particularly suitable for employment in radio link traveling wave tubes.

Abstract: For conducting very high microwave power at very high frequencies, circular waveguide transmitting a circular-electric-field mode is used. The vacuum-tight window of an electron tube is often the element with lowest power-handling capability. The inventive window has two dielectric plates with a space between them. There is a gap in the waveguide inner wall through which a dielectric fluid is circulated between the plates to cool them. The gap leads to a region containing wave-absorbing material such as water to absorb modes other than the circular-electric-field mode.

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 compact cryogenically coolable choked waveguide particularly for low-noise input coupling into a cryogenically cooled device, such as a maser or parametric amplifier, utilizes coaxial stainless steel support tubes surrounding the waveguide and connected in cascade to provide a folded low thermal conduction path. The edges of the tubes connected are welded.

Abstract: A mechanically scanned antenna system having a multiport rotary switch for sector scanning is disclosed. The switch includes a stationary subassembly and a rotating subassembly. The stationary subassembly contains the input ports and the rotating subassembly contains the multiple output ports associated with each input port. Each of the multiple output ports of the switch is sequentially activated through its designed active sector to produce the desired antenna scan pattern. The stationary subassembly includes a barrier member which is rotatable to selectively orient and maintain orientation of the active region of the antenna system at any position through 360.degree..