Abstract: A radio frequency coupling structure comprising (1) a substrate that forms a top side of a waveguide, (2) a first conductive layer disposed on a bottom side of the substrate, (3) a second conductive layer incorporated within the substrate, (4) a through via that is communicatively coupled to the first conductive layer and extends through an opening in the second conductive layer toward a top side of the substrate, and/or (5) a ring slot formed around the through via in the first conductive layer. Various other apparatuses, systems, and methods are also disclosed.

Abstract: Some variations provide an alkali metal or alkaline earth metal atom source (e.g., vapor cell) with a solid ionic conductor and a mixed ion-electron conductor electrode. Mixed ion-electron conductor electrodes are used as efficient sources and/or as sinks for alkali metal or alkaline earth metal atoms, thus enabling electrical control over metal atom content in the vapor cell. Some variations provide a vapor-cell system comprising: a vapor-cell region configured to allow a vapor-cell optical path into a vapor-cell vapor phase; a first electrode containing an mixed ion-electron conductor that is conductive for an ion of at least one element selected from Rb, Cs, Na, K, or Sr; a second electrode electrically isolated from the first electrode; and an ion-conducting layer between the first electrode and the second electrode. The ion-conducting layer is ionically conductive for at least one ionic species selected from Rb+, Cs+, Na+, K+, or Sr2+.

Abstract: Aspects of the present disclosure are directed to pressure sensing. As may be implemented in accordance with one or more embodiments, an external energy field is applied to a resonant circuit having inductive conductors separated by a compressible dielectric, for wirelessly detecting pressure. Specifically, the resonant circuit is responsive to the energy field and applied pressures by operating in respective states exhibiting different resonant frequencies that are based upon pressure-related compression of the compressible dielectric. These resonant frequencies, or a change in the resonant frequencies, can be used as an indication of the pressure.

Abstract: A transition (100, 300) from microstrip to waveguide, the waveguide comprising first (120) and second (105, 105?, 105?) interior surfaces connected by side walls (115, 116) whose height (h1, h2, h3) is the shortest distance between said interior surfaces, and a microstrip structure (130, 135, 110) extending into the closed waveguide (105). The microstrip structure comprises a microstrip conductor (130, 135) on a dielectric layer arranged on said first interior surface. The microstrip conductor (130,135) comprises and is terminated inside the closed waveguide by a patch (135). The height (h1) of the side walls (115, 116) along the distance that the microstrip conductor (130, 135) extends into the closed waveguide (105) being less than half of the greatest height (h3) beyond the microstrip structure's protrusion into the closed waveguide (105).

Abstract: A multi-pole filter antenna may include aperture-coupled non-dominant mode cavity resonators, and an aperture-coupled dominant mode patch antenna. The filter antenna may be implemented in a multilayer printed circuit board or similar structure. The filter antenna may for example operate in the Ku-Band, the Ka-Band, the C-Band, or another band.

Abstract: The present disclosure provides example resonance filters and methods for making the same. The resonance filter includes a first layer having n adjacent resonance cavities, n being at least 2 and said cavities each being separated from one another by a partition wall. The resonance filter also includes a second layer having at least n?1 coupling cavities. The cavities in the first layer are formed as resonance cavities and those in the second layer are formed as (a) coupling cavity/cavities and are open on one side. The second layer is arranged on the first layer in such a way that the resonance cavities in the first layer are interconnected by the coupling cavity/cavities in the second layer. Further, the resonance filter is configured as a monolithic component.

Abstract: An on-axis rf power coupler for a superconducting particle accelerator includes a coaxial coupler tube that passes through a rf waveguide stub connected to a rf power source. The coupler tube is movable in translation along the axis of the beam path by a piezoelectric drive to permit variation of the coupling between the rf power source and the resonant signal in the accelerator. A tubular rf window extending through the waveguide stub, together with a vacuum bellows assembly connected to the coupler tube, isolate the vacuum inside the accelerator cavity from the vacuum in the rf waveguide and stub. A choke joint in the wall of the waveguide selectively passes unwanted HOM signals out of the waveguide stub and away from the accelerator cavity, where they are dissipated by ferrite tiles on the coupler tube. The upstream end of the coupler tube and a tubular extension of the accelerator cavity form a coaxial line for introducing rf power into the accelerator.

Abstract: The invention concerns a waveguide filter (200NP) for microwaves, characterized in that it has, at least on part of its length, a cross-section having two mutually non-parallel opposite sides (111, 111?), for example trapezoid. The use of such a shape enables the power threshold for forming self-maintained electron avalanche discharges to substantially increased and satisfactory filtering properties to be obtained. The invention also concerns the use of such a filter in a high-power microwave transmitter operating in X and Ka bands, in particular for space applications.

Abstract: A transverse acoustic wave resonator includes a base, a resonator component, a number of driving electrodes fixed to the base and a number of fixing portions connecting the base and the resonator component. The resonator component is suspended above a top surface of the base and is perpendicular to the base. The driving electrodes are coupling to side surfaces of the resonator component. The resonator component is formed in a shape of an essential regular polygon. The driving electrodes and the resonator component jointly form an electromechanical coupling system for converting capacitance into electrostatic force. Besides, a capacitive-type transverse extension acoustic wave silicon oscillator includes the transverse acoustic wave resonator and a method of fabricating the transverse acoustic wave resonator are also disclosed.

Abstract: A resonance element according to an embodiment transmits a radio-frequency signal, and includes a first substrate, a second substrate, a first circuit element formed on the first substrate, a second circuit element formed on the second substrate, and a transmission line connecting the first circuit element and the second circuit element, and a peak of even mode resonance in which the first circuit element and the second circuit element resonate in the coordinated phase is within a bandwidth of a transmission signal, and a peak of odd mode resonance in which the first circuit element and the second circuit element resonate in a reverse phase is outside the bandwidth.

Abstract: A filter includes: a container; at least one barrier, an input device and an output device. The at least one barrier divide the space of the container into at least two resonant cavities. Each resonant cavity has a harmonic oscillator disposed therein. The harmonic oscillators includes a supporter and a carbon nanotube structure disposed on a surface of the supporter.

Abstract: A multi-mode cavity filter, comprising: at least one dielectric resonator body incorporating a piece of dielectric material, the piece of dielectric material having a shape such that it can support at least a first resonant mode and at least a second substantially degenerate resonant mode; a layer of conductive material in contact with and covering the dielectric resonator body; and a coupling structure comprising at least one electrically conductive coupling path for at least one of inputting signals to the dielectric resonator body and outputting signals from the dielectric resonator body, the at least one electrically conductive coupling path being arranged for at least one of directly coupling signals to the first resonant mode and the second substantially degenerate resonant mode in parallel, and directly coupling signals from the first resonant mode and the second substantially degenerate resonant mode in parallel.

Abstract: A harmonic suppression resonator comprises a plurality of waveguide resonators that resonate in TE mode, in which harmonic suppression resonator, adjoining resonators are coupled via a plurality of coupling windows. Four coupling windows 33bc1, 33bc2, 33bc3 and 33bc4 are provided between a resonant region 51b and a resonant region adjoining the resonant region 51b. These coupling windows allow fundamental wave modes of the adjoining resonators to be coupled mainly by magnetically coupling. The coupling windows 33bc3 and 33bc4 allow second harmonic modes of the adjoining resonators to be electrically coupled, and the coupling windows 33bc1 and 33bc2 allow the second harmonic modes of the adjoining resonators to be magnetically coupled. By causing the amount of the electrically coupling and the amount of the magnetically coupling to be substantially equal, the coupling of the second harmonic modes is negated, whereby propagation of the second harmonic is blocked.

Abstract: A method comprising polarizing and coupling an electromagnetic beam to a first-order transverse electric (TE1) mode with respect to a parallel plate waveguide (PPWG) integrated resonator comprising two plates and a cavity, sending the electromagnetic beam into the PPWG integrated resonator to excite the cavity by the TE1 mode and cause a resonance response, and obtaining wave amplitude data that comprises a resonant frequency, and obtaining the refractive index of fluids filling the cavity via the shift in resonant frequency.

Abstract: A filter includes: a container; at least one barrier, an input device and an output device. The at least one barrier divide the space of the container into at least two resonant cavities. Each resonant cavity has a harmonic oscillator disposed therein. The harmonic oscillators includes a supporter and a carbon nanotube structure disposed on a surface of the supporter.

Abstract: The present invention relates to a feeding structure for coupling a feedline to a cavity. To increase the coupling, which can contribute to achieving a broad bandwidth, a feeding structure is proposed comprising a carrier substrate, a top conductor plane of a cavity formed in said carrier substrate, a feedline substrate covering said top conductor plane, a signal conductor of a feedline, said signal conductor being formed in or on said feedline substrate opposite said top conductor plane, a via probe connected to said signal conductor and leading through said feedline substrate and said top conductor plane into said cavity, a ring-shaped aperture formed in said top conductor plane around said via probe, and at least one slot-shaped aperture formed in said top conductor plane starting at said ring-shaped aperture and leading away from said via probe.

Abstract: A method and apparatus is described comprising of a plurality of electromagnetic resonant structures coupled to a common process or reaction volume, such that resonance of each structure is maintained while the process or reaction volume is a part of each resonant structure. At the same time, each resonant structure is matched to its respective electromagnetic generator. Such a system allows each generator and its delivery system to run at rated power, with summation of all the powers occurring in the common process or reaction volume. In various embodiments of this invention, the various electromagnetic generators can run at the same or different frequencies. The various resonant structures can be single mode or multimode, or a mixture of single mode and multi mode. The various resonant structures can be arranged spatially in order to couple several structures to the process or reaction volume.

Abstract: An optical resonator includes a master resonator configured to resonate an electromagnetic wave, one structure or a pair of structures adjacent to each other, each of which is arranged at a position that overlaps one of resonance modes of the master resonator, is made up of a material in which a real part of a permittivity assumes a negative value, and an absolute value of the real part is larger than an absolute value of an imaginary part of the permittivity, and has a size which makes scattering that the electromagnetic wave suffers be Rayleigh scattering, and one or a plurality of particles, each of which is laid out near the structure by a distance smaller than the size of the structure.

Abstract: A microwave filter based on the combination of dual-mode and single-mode cavities. The single-mode cavity symmetrically extends from the dual-mode cavity with respect to the symmetric reference plane to form the so called extended doublet network. The microwave filter in extended-doublet configuration exhibit high frequency selectivity since it has a pair of finite frequency transmission zeros on the upper and lower stopband. The design concept can also be applied to build higher order filters.

Abstract: A microwave filter having a resonator comprising a cylindrical structure having conductive walls filled with a conductor material. The cylindrical structure is recessed inside a multi-layered substrate. First and second conductive coupling arms are disposed on the top layer of the substrate for coupling signals to the cylindrical structure. The conductive coupling arms are physically separated from the cylindrical structure by a dielectric layer. The first and second conductive coupling arms extend away from the center of the cylindrical structure to form a microstrip line. The cylindrical structure further comprises a bottom portion having a solid conductive bottom plate perpendicular to the axis of the cylinder. A bottom conductive ground layer separated from the conductive bottom plate by a second dielectric layer.

Abstract: A phase cancellation circuit for a cavity filter including a sampler loop assembly arranged to receive an input signal, a variable loop assembly connected to the sampler loop assembly by a cable, wherein the variable loop assembly is arranged to transmit an output signal from cavity filter, wherein the sampler loop assembly samples a cancellation signal at an isolation frequency from the input signal and transmits the cancellation signal to the variable loop assembly via the cable, and, wherein the cable has a length equal to a multiple of a half-wavelength at the desired isolation frequency, wherein the cancellation signal undergoes a 180° phase shift by traveling through the cable, wherein the variable loop assembly combines the cancellation signal with the input signal to cancel the input signal at the isolation frequency due to the 180° phase shift for creating the output signal with a notch at the isolation frequency.

Abstract: A filter for use with a waveguide which is part of a low-noise block (LNB) for use with VSAT, satellite communications systems is described. The filter is cast into the waveguide wall at the same time as the waveguide is manufactured providing a waveguide filter with a consistent filtering performance.

Abstract: The elliptical response bandpass filter according to the invention comprises a plurality N of cavities connected in series by means of in-phase coupling loops; the first cavity is in addition connected to the last by a complementary phase-inversion coupling loop in order to generate transmission zeros at determined frequencies.

Abstract: A radio frequency (RF) cavity resonator having a resonator chamber and one or more RF coupling loop assemblies is presented. The RF coupling loop assembly has a connector with a first connector interface coupled to an inner conductor and a second connector interface coupled to an outer conductor, the first and second connector interfaces forming a pair when mated, the second connector interface rotatable about a collinear axis of the connector and the first connector interface not rotatable about the collinear axis of the connector; a wire loop coupler; and a bandwidth selection element at least partially coupled to the coupling loop assembly. In response to changing the bandwidth selection setting while the RF cavity resonator is operational, the wire loop changes orientation about the collinear axis of the connector and causes the RF resonator chamber to output an RF carrier signal having a bandwidth of the new bandwidth setting.

Abstract: A filter includes: a container; at least one barrier, an input device and an output device. The at least one barrier divide the container into at least two resonant cavities. Each resonant cavity has a harmonic oscillators disposed therein. At least one of the harmonic oscillators comprises a supporter and a carbon nanotube structure disposed on a surface of the supporter.

Abstract: Various exemplary embodiments include a cavity having a tuning assembly with tunable capacitive coupling. The tuning assembly may have a recess having a specified depth, designed for a default magnitude of coupling into the cavity. A sleeve may be fully inserted within the recess to have the structure operate at that default coupling magnitude. If a different amount of coupling is desired, the sleeve may be inserted to a particular depth that only includes part of the recess, enabling repeatable tuning of a plurality of cavities.

Abstract: Provided is an apparatus for transitioning a millimeter wave between dielectric waveguide and transmission line using a millimeter wave transition structure formed by the dielectric waveguide, the transmission line, and a slot to transition a signal with lower losses. The apparatus includes: transmission lines disposed respectively at input and output terminals on an uppermost dielectric substrate in a signal transition direction and adapted to transition a signal; a dielectric waveguide formed by a via array disposed between top and bottom ground surfaces of a lowermost dielectric substrate in the signal transition direction as a signal transition path; and slots disposed at a signal transition path of an upper ground surface of each dielectric substrate to connect the transmission lines to the dielectric waveguide so as to transition a signal from the transmission line of the input terminal to the transmission line of the output terminal through the dielectric waveguide.

Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide in which a half-wavelength TE mode resonator is formed; an E plane coupling window formed in a wall portion orthogonal to an H plane out of wall portions constructing the TE mode resonator in the waveguide; an output line provided at the edge on the side of the wall portion parallel with the H plane on the E plane coupling window, and magnetically coupled to electromagnetic waves in the TE mode resonator; and another output line provided at the edge on the side of the wall portion parallel with the H plane in the E plane coupling window, and magnetically coupled to the electromagnetic waves.

Abstract: A waveguide-type dielectric filter suitable for wideband filter applications made of a metallized dielectric material is provided. The filter includes two or more mutually coupled resonators disposed in a longitudinal manner. The coupling between adjacent resonators is provided and adjusted by slots or through holes. The dielectric block is covered with metal ground coating with the exception of an uncoated area at the input and output that creates two contact pads on one surface of the dielectric block that are electrically isolated from the metal ground coating. Metallized blind holes are formed on the opposing surface of the dielectric block with respect to the contact pads. These blind holes effectively move the ground plane closer to the contact pad, which, in turn increases the coupling between the input and output resonators and external circuitry, which is essential for building wide bandwidth band pass filters.

Abstract: A tuneable bandpass filter includes a plurality of coupled resonators. A common structure of the filter includes at least one common coupling or one common resonator. An upper loop includes first and second end resonators coupled together by a signal path and further includes at least one further signal path extending between end resonators. The further signal path includes at least one further resonator with the end resonators being coupled to the common structure. A lower loop includes first and second end resonators coupled together by a signal path and further includes at least one further signal path extending between end resonators. The further signal path includes at least one further resonator with the end resonators being coupled to the common structure.

Abstract: A method comprising polarizing and coupling an electromagnetic beam to a first-order transverse electric (TE1) mode with respect to a parallel plate waveguide (PPWG) integrated resonator comprising two plates and a cavity, sending the electromagnetic beam into the PPWG integrated resonator to excite the cavity by the TE1 mode and cause a resonance response, and obtaining wave amplitude data that comprises a resonant frequency, and obtaining the refractive index of fluids filling the cavity via the shift in resonant frequency.

Abstract: A high-frequency module according to the present embodiment includes a substrate, a circuit board, and a resonator. The substrate has an input-output portion for high-frequency signals formed on one surface thereof. The circuit board includes a dielectric waveguide line with its end face exposed, and is placed on the one surface of the substrate such that a virtual plane extending beyond the end face is intersected by the one surface of the substrate. The resonator includes input-output end portions for high-frequency signals at ends thereof, in which one of the input-output end portions is connected to the end face of the dielectric waveguide line, and the other thereof is connected to the input-output portion of the substrate.

Abstract: A multilayer dielectric substrate includes a first cavity-resonance suppressing circuit that suppresses cavity resonance of a first signal wave and a second cavity-resonance suppressing circuit that suppresses cavity resonance of a second signal wave, a frequency thereof being different from that of the first signal wave. These cavity-resonance suppressing circuits respectively include openings formed in a surface-layer ground conductor, an impedance transformer with a length of an odd multiple of about ¼ of in-substrate effective wavelength of a signal wave, a tip-short-circuited dielectric transmission line with a length of an odd multiple of about ¼, of in-substrate effective wavelength of a signal wave, a coupling aperture formed in an inner-layer ground conductor, and a resistor formed in the coupling aperture. The multilayer dielectric substrate that suppresses cavity resonance of signal waves of a plurality of frequencies.

Abstract: A micromachined air-cavity resonator, a method for fabricating the micromachined air-cavity resonator, and a band-pass filter and an oscillator using the same are provided. In particular, a micromachined air-cavity resonator including a current probe fabricated together when the air-cavity resonator is fabricated, and a groove structure for rejecting detuning effect when an external circuit of a package substrate is coupled to the current probe, a millimeter-wave band-pass filter using the same, and a millimeter-wave oscillator using the same are provided. The micromachined air-cavity resonator includes a cavity structure which comprises a current probe simultaneously formed through a fabrication process, and a groove structure; and a package substrate integrated with the cavity structure. Thus, the micromachined air-cavity resonator can be easily fabricated by etching a silicon substrate and easily integrated to the package substrate using the flip-chip bonding.

Abstract: In resonant elements 102 to 105 constituting a resonant circuit, an uncontrolled cross coupling which exists between two resonant elements is controlled by using a coupling element 106 which is newly arranged between the resonant elements, whereby it is possible to create a state where two resonant elements are not coupled with each other or a state where the amount of the coupling is reduced, which states are difficult to be realized on a plane. As a result, it is possible to improve characteristics of a planar filter.

Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide (3) in which a half-wavelength TE mode resonator (2) is formed; an E plane coupling window (4) formed in a wall portion (3a) orthogonal to an H plane out of wall portions (3a) to (3e) constructing the TE mode resonator (2) in the waveguide (3); an output line (5a) provided at the edge on the side of the wall portion (3d) parallel with the H plane on the E plane coupling window (4), and magnetically coupled to electromagnetic waves in the TE mode resonator (2); and another output line (5b) provided at the edge on the side of the wall portion (3e) parallel with the H plane in the E plane coupling window (4), and magnetically coupled to the electromagnetic waves.

Abstract: A RF device such as a tower mounted amplifier (TMA), mast-head amplifier (MHA), or Tower Mounted Boosters (TMB) includes a housing having a plurality of cavities and an input and an output, the input being coupled to the antenna and the output being coupled to a base station. The housing includes a transmission path holding multiple coaxial resonators. The housing further includes multiple receive paths including at least one path having a plurality of cavities, each cavity containing a dielectric resonator. The metallic transmit resonator nearest the antenna input is coupled to the first dielectric resonator via a common resonant wire. The last dielectric resonator in the receive path is coupled to a first metallic resonator of a downstream clean-up filter via another common resonant wire.

Abstract: Methods and apparatus for controlling characteristics of a plasma, such as the spatial distribution of RF power and plasma uniformity, are provided herein. In some embodiments, an apparatus for controlling characteristics of a plasma includes a resonator for use in conjunction with a plasma reactor, the resonator including a source resonator for receiving an RF signal having a first frequency; a return path resonator disposed substantially coaxially with, and at least partially within, the source resonator; and an outer conductor having the source resonator and the return path resonator disposed substantially coaxially with, and at least partially within, the outer conductor, the outer conductor for providing an RF ground connection.

Abstract: An improved high frequency filter displays the following features: the high frequency filter displays transmission behavior with a coupling impedance resonance having at least one blocking point at a frequency, the blocking point at the frequency being adjustable by presetting and/or preselecting a defined capacitive and inductive coupling between two coaxial resonators, one immediately following the other on a signal path.

Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide (3) in which a half-wavelength TE mode resonator (2) is formed; an E plane coupling window (4) formed in a wall portion (3a) orthogonal to an H plane out of wall portions (3a) to (3e) constructing the TE mode resonator (2) in the waveguide (3); an output line (5a) provided at the edge on the side of the wall portion (3d) parallel with the H plane on the E plane coupling window (4), and magnetically coupled to electromagnetic waves in the TE mode resonator (2); and another output line (5b) provided at the edge on the side of the wall portion (3e) parallel with the H plane in the E plane coupling window (4), and magnetically coupled to the electromagnetic waves.

Abstract: A radio frequency (RF) cavity resonator having a resonator chamber and one or more RF coupling loop assemblies is presented. The RF coupling loop assembly has a connector with a first connector interface coupled to an inner conductor and a second connector interface coupled to an outer conductor, the first and second connector interfaces forming a pair when mated, the second connector interface rotatable about a collinear axis of the connector and the first connector interface not rotatable about the collinear axis of the connector; a wire loop coupler; and a bandwidth selection element at least partially coupled to the coupling loop assembly. In response to changing the bandwidth selection setting while the RF cavity resonator is operational, the wire loop changes orientation about the collinear axis of the connector and causes the RF resonator chamber to output an RF carrier signal having a bandwidth of the new bandwidth setting.

Abstract: An rf pulse compressor has a single high Q cavity resonator fed by a four port hybrid coupler which is connected to the resonator at coupling ports located at the intersection of two of the resonator's orthogonal axes with the resonator cavity walls. The hybrid coupler divides pulse power from an rf pulse power source and excites two space and phase orthogonal modes in the single cavity, the stored energy of which aids in producing compressed pulses at the output of the hybrid. On-axis perturbations in the cavity walls can be used to lock the orthogonal orientation of the modes excited in the cavity.

Abstract: A device and method is provided that includes a window for coupling a signal between cavities of a device or between cavities of different devices. A wall or microstructure is formed on a surface and defines a cavity. The window is formed in the wall and comprises at least a portion of the wall and is electrically conductive. The cavity can be sized to resonate at various frequencies within the terahertz portion of the electromagnetic spectrum and generate an electromagnetic wave to carry the signal. The window allows surface currents to flow without disruption on the inside surface of the cavity.

Abstract: A resonator cavity for supporting a plurality of resonant modes and filtering electromagnetic energy includes a cavity and a resonator element with a mounting flange. The cavity is defined by a top end wall, a bottom end wall and a sidewall and has a longitudinal axis along its length is defined. The resonator element is positioned within the cavity along the longitudinal axis and includes a mounting flange. The resonator element is only in physical contact with the cavity through the mounting flange at a mounting location and where at least one resonant mode of the electromagnetic energy exhibits a local minima. The dimensions of the cavity and the resonator element are selected so that the associated electromagnetic energy is defined by an electromagnetic field pattern that substantially repeats itself at least twice along the length of the resonator.

Abstract: Provided is a dielectric waveguide filter. The filter includes: a multi-layered structure of dielectric substrates having first and second ground planes at its top and bottom; first, second, and third waveguide resonators disposed at multiple layers within the multi-layered structure; converters for signal transition between input/output ports and the first and third waveguide resonators; first vias for forming the first, second, and third waveguide resonators; and second vias disposed at a boundary surface of the first waveguide resonator and the third waveguide resonator.

Abstract: Projecting elongate stub walls are provided on the planar surfaces of a substrate at positions where bonding of the substrate to a clamping lid or base is to be carried out. On firing of the substrate, the surfaces thereof are mechanically processed but since the stub walls protrude from the substrate, the grinding and polishing tools make contact with the surfaces of these stub walls, rather than with the entire substrate surface. As a result, the area of the substrate to be processed is minimised and problems with dishing and erosion are alleviated. This allows the clamping lid, or frame to be bonded, using conventional conductive adhesive processes, avoiding the cracking and stress problems associated with non-uniformity of the surface of the ceramic substrates.

Abstract: A triple-mode filter is disclosed, the triple-mode filter including a cavity for confining electromagnetic waves and a metallic block acting as a resonator within that cavity. The metallic block does not contact the conductive walls of the cavity, but is instead suspended by a support element. Triple-mode resonators may be combined to produce bandpass filters having three or more poles. In other configurations, triple-mode cavity metallic resonators may be coupled to triple-mode cavity ceramic resonators or to combline resonators to achieve various filtering functions and performances suitable for different applications.

Abstract: A method and apparatus for producing a distributed plasma at atmospheric pressure. A distributed plasma can be produced at atmospheric pressure by using an inexpensive high frequency power source in communication with a waveguide having a plurality particularly configured couplers disposed therein. The plurality of particularly arranged couplers can be configured in the waveguide to enhance the electromagnetic field strength therein. The plurality of couplers have internal portions disposed inside the waveguide and spaced apart by a distance of ½ wavelength of the high frequency power source and external portions disposed outside the waveguide and spaced apart by a predetermined distance which is calculated to cause the electromagnetic fields in the external portions of adjacent couplers to couple and thereby further enhance the strength of the electromagnetic field in the waveguide. Plasma can be formed in plasma areas defined by gaps between electrodes disposed on the external portions.

Abstract: A cavity resonator is provided which includes a shielded enclosure enclosing a volume and a unitary conductor disposed within the volume, the unitary conductor having a first inductor portion and a transmission line portion. The transmission line portion is included in a transmission line having a reference conductor separated from the transmission line portion by a dielectric element. An active semiconductor device is coupled to the unitary conductor, and is operable to conduct a current to the unitary conductor at a resonant frequency of the unitary conductor.

Abstract: A bandpass filter makes use of at least one waveguide cavity that is thermally compensated to minimize drift of a resonant frequency of the cavity with thermal expansion of cavity components. The compensation relies on deformation of the shape of at least one cavity surface in response to thermally-induced dimensional changes of the cavity. A control rod is used to limit the movement of a point on the deformed surface, while the rest of the surface moves with the thermal expansion. The control rod is made of a material having a coefficient of thermal expansion that is significantly different than that of other filter components. The rod may also be arranged to span more thermally expandable material than defines the filter such that, as the filter expands, the point of deflection is moved toward the interior of the filter beyond its original position.