Abstract: A method of tuning the frequency of a waveguide filter including the step of removing dielectric material from one or both of the first and second opposed exterior side surfaces of the waveguide filter to cause a change in the center frequency of the waveguide filter. In one embodiment, dielectric material is removed from one or both of the first and second opposed exterior side surfaces of the waveguide filter in unequal amounts wherein the tuned waveguide filter includes first and second slits defined in the respective first and second opposed exterior side surfaces which extend unequal first and second distances into the body of the waveguide filter.

Abstract: A method and an apparatus are provided for providing a tunable substrate integrated waveguide (SIW) for which a parameter of at least some element or portion thereof may be altered or varied to alter the propagation of a signal propagating through the SIW thereby achieving a tunable SIW. In some embodiments a plurality of capacitively variably loaded transverse slots achieve the tunability for the SIW.

Abstract: A millimeter wave transmission line filter having a plurality of filter pole determining coupled cavities fabricated with a multiple lithographic layer micro-machining process. The filter cavities are oriented perpendicular to an underlying substrate element in order to achieve micromachining, fabrication and accuracy advantages. Multiple filters can be used in a frequency multiplex arrangement as in a duplexer. Radio frequencies in the 15 to 300 gigahertz range are contemplated.

Abstract: Various exemplary embodiments relate to an improved coupler for resonant cavities and dielectric resonators. The coupler may permit accurate tuning of electromagnetic signals within desired frequency ranges. The coupler may be secured to a movable tuning device by a plurality of securing members. Each securing member may be separate, having no contact with any other securing member.

Abstract: Provided are a resonant element and resonator filter with a frequency tunable layer structure and a method of tuning a frequency of a resonator filter. A resonant element with a frequency-tunable layer structure includes a waveguide layer through which an electric wave is transmitted, a frequency adjustment layer positioned on at least one of an upper layer and a lower layer of the waveguide layer, and configured to change at least one of a height and a structure of the resonant element, and an outer layer positioned outwardly from the waveguide layer and the frequency adjustment layer, and constituting an external structure of the resonant element. Consequently, it is possible to reduce economic and temporal waste caused by remanufacturing a resonator filter because the frequency characteristics of the manufactured resonator filter do not coincide with designed frequency characteristics.

Abstract: A tunable band-pass filter includes: a rectangular waveguide including a first and a second waveguide parts, which are acquired by dividing the rectangular waveguide along an E-plane of the rectangular waveguide at a center position of an H-plane in the rectangular waveguide; a metal plate sandwiched by the first and the second waveguide parts in such a way as to be parallel to the E-plane; at least one dielectric plate arranged in the rectangular waveguide in such a way as to extend in a longitudinal extension direction of the metal plate; and a drive mechanism changing a relative position relationship between the dielectric plate and the metal plate from the outside.

Abstract: The invention relates to an improved HF cavity filter characterized by the following features: the housing cover (17) is made of a circuit board (21); the at least one additional hole (29) is made in the circuit board (21), in which a tuning bushing soldered at the outer circumference to an electrically conductive layer (25) on the circuit board is inserted; the tuning element (37) can be threaded to a varying depth into the tuning bushing (31); at least one electrically conductive structure is implemented on the circuit board (21); and the dielectric conductive structure comprises at least one conductor and/or at least one SMT component and/or at least one HF overcoupling device.

Abstract: A band-pass filter includes a photonic crystal having a local mode that generates a pass band in a stop band formed by Bragg reflection, a transmission channel that limits electromagnetic waves propagating in the photonic crystal to a mode in which an amplitude direction of an electrical field is a particular direction; and a magnetic field-applying unit for applying to the photonic crystal a DC magnetic field in a direction perpendicular to a propagation direction of the electromagnetic waves. The photonic crystal includes a periodic structure including a low permittivity dielectric member and a plurality of high permittivity dielectric members periodically arranged in the low permittivity dielectric member so that the Bragg reflection occurs in the periodic structure, and a magnetic member disposed in the periodic structure.

Abstract: An RF cavity filter is disclosed. The disclosed filter includes: a housing having at least one cavity defined; a cover coupled to an upper portion of the housing; at least one resonator contained within the at least one cavity; at least one hole formed in the cover; at least one grounding bolt configured to be inserted into the hole, having a screw thread formed on a part of an outer perimeter, and having a center hole in a center portion; and at least one tuning bolt inserted into the housing through the center hole along a screw thread formed on an inner perimeter of the center hole, where the grounding bolt has a flange part formed on a lower portion that is in contact with the tuning bolt and a lower portion of the cover.

Abstract: A dielectric resonator filter comprising a metal wall (11) that is configured with metal cavities. Dielectric resonators (12, 14, 15) and (16) can be placed in the metal cavities and configured as a set of cylindrical TE mode resonators (12) and (14) and a set of rectangular HE mode resonators (15) and (16). Separating walls (13) are disposed between the dielectric resonators (12, 14, 15) and (16), which include tunable irises (17) for electromagnetic mixed coupling between the cylindrical TE mode resonators (12) and (14) and the rectangular HE mode resonators (15) and (16). The rectangular HE mode resonators (15) and (16) are configured to push far up the TE mode in frequency. This leads to an easy separation of two degenerate HE modes, a wide spurious free stop band and also achieves electric coupling without using any additional coupling member.

Abstract: The filter has a switch function of selectively transmitting a transmission signal through one of first and second branch waveguides branching from a primary waveguide. The filter includes resonators disposed in the first and second branch waveguides. The resonator includes a space formed inside a metal cover, a central conductor disposed inside the space, and a short-circuiting plate. The central conductor has one end grounded to an outer conductor. The short-circuiting plate allows the neighborhood of an open end of the central conductor to be selectively conducted to the outer conductor. The filter performs a selection from the first and second branch waveguides by switching electrical conductivity in a region between the neighborhood of the open end of the central conductor and the outer conductor.

Abstract: A structure and method for adjusting the bandwidth of a ceramic waveguide filter comprising, in one embodiment, a monoblock of dielectric ceramic material defining respective steps and respective input/output through-holes extending through the monoblock and the respective steps. In one embodiment, the steps are defined by notches in the monoblock and the input/output through-holes define openings terminating in the notch. The bandwidth of the ceramic waveguide filter may be adjusted by adjusting the height/thickness and direction of the steps relative to an exterior surface of the monoblock and/or the diameter of the input/output through-holes.

Abstract: A tunable filter having an electronically tunable center frequency and dynamic bandwidth control over a large tuning range. High-Q continuously tunable evanescent-mode cavity resonators and filters using reliable RF MEMS actuators. One embodiment is a 3.4-6.2 GHz (1.8:1 tuning ratio) continuously tunable electrostatic MEMS resonator with quality factor of 460-530, with a volume of 18×30×4 mm including the actuation scheme and biasing lines. A tunable resonators is also disclosed with a 2.8:1 (5.0-1.9 GHz) tuning ratio, and Q of 300-650.

Abstract: A tunable filter for enabling the adjustment of tuning characteristics includes: a housing, in which multiple cavities are defined by partitions; a resonator contained in the cavity; at least one sliding member installed over the resonator; a main cover coupled to an upper portion of the housing; and at least one tuning element coupled to a lower portion of the sliding member and made of a metallic material. The tuning element is coupled to the sliding member by a rotatable bolt, and the bolt is coupled to the tuning element at a point that is a particular distance away from a center of the tuning element. The tunable filter using a sliding system according to certain embodiments of the present invention has the advantage of enabling adjustment of tuning characteristics by way of the rotation of the tuning element, and accordingly, can be used adaptively in various environments.

Abstract: A tunable filter for expanding tuning range includes: a housing, which has multiple cavities defined by partitions; a resonator contained in the cavity; at least one sliding member installed over the resonator; a main cover coupled to an upper portion of the housing; and at least one tuning element coupled to a lower portion of the sliding member and made of a metallic material. Tuning is accomplished by a sliding motion of the sliding member, and the resonator includes a cylindrical first conductor and a second conductor coupled to an upper portion of the cylindrical conductor, where a cross section of the second conductor is shaped as a circle with a portion removed such that an area of overlap between the tuning element and the second conductor is varied according to a sliding of the tuning element.

Abstract: A waveguide filter comprises a dielectric board on at least one of the two E-planes of a rectangular waveguide. The dielectric board comprises a conductive pattern formed on one surface thereof and having a slit extending in a signal propagation direction, and a ground pattern formed on the other surface.

Abstract: A tuneable filter comprising a filter body defining a tuning cavity; a tuning member within the tuning cavity; and, a linear actuator adapted to displace the tuning member within the cavity to tune the filter; the linear actuator comprising a motor; a drive arm connected to the motor and extending along a drive axis, the drive arm being adapted to be rotated about the drive axis by the motor; an extension arm extending along the drive axis being connected at one end to the tuning member and being in engagement with the drive arm at the other end; the engagement between the drive arm and extension arm being arranged such that rotation of the drive arm about the drive axis displaces the extension arm along the drive axis; each of the drive arm and extension arm comprising an end stop, the end stops being arranged such that as the extension arm reaches the end of its range of travel towards the drive arm the drive arm end stop rotates into abutment with the extension arm end stop, preventing further rotation of

Abstract: The present invention relates to a flexible cap system optimized for thermally-compensated technology microwave resonators. More specifically, this invention proposes a multiple-membrane flexible wall system for thermally-compensated filters and OMUX. The use of a multi-membrane flexible wall, in particular as sealing cap for a resonant cavity of an OMUX channel, makes it possible: to reduce the thermal resistance of the flexible wall, while maintaining an equivalent level of mechanical stresses exerted on said wall for a given displacement; or to reduce the mechanical stresses exerted on the flexible wall for a given displacement, while maintaining one and the same thermal resistance for said wall; or to increase the deformation of the flexible wall by maintaining an equivalent level of mechanical stresses and by maintaining an equivalent thermal resistance.

Abstract: An actively tunable waveguide-based iris filter having a first part including a first portion of a deformable iris filter cavity having an inlet and an outlet; a second part operatively coupled with the first part and including a second portion of the deformable iris filter cavity having a deformable membrane operatively coupled with the first portion of a deformable iris filter cavity; the first portion and the second portion together forming the deformable iris filter cavity of the tunable waveguide-based iris filter; and means for moving the deformable membrane, whereby movement of the deformable membrane changes the geometry of the deformable iris filter cavity for causing a change in the frequency of a signal being filtered by the filter. The tunable filter is fabricated using a MEMS-based process including a plastic micro embossing process and a gold electroplating process. Prototype filters were fabricated and measured with bandwidth of 4.05 GHz centered at 94.79 GHz with a minimum insertion loss of 2.

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: One embodiment of the present invention includes a waveguide. The waveguide comprises an elongated member having a conductive bottom surface and a hollow channel. The hollow channel is defined by a first conductive sidewall, a second conductive sidewall, and a conductive inner surface. The waveguide also comprises a plurality of conductive ridge portions projecting from the conductive inner surface and extending between the first conductive sidewall and the second conductive sidewall. The conductive ridge portions can partition the hollow channel into a plurality of hollow recesses. The waveguide further comprises a plurality of switches associated with each of at least one of the plurality of conductive ridge portions. At least one of the plurality of switches associated with a respective one of the plurality of conductive ridge portions can be activated to couple the respective one of the plurality of conductive ridge portions to the conductive bottom surface.

Abstract: A variable radio frequency band filter includes a housing with a plurality of cavities, a plurality of resonators, wherein one resonator is arranged in each cavity, and a tuning arrangement having a plurality of tuning structures. One of the tuning structures is arranged in each of the cavities. The tuning structures of multiple cavities are mechanically connected such that the tuning structures may be shifted simultaneously in order to simultaneously vary the resonance frequencies of the cavities. Each tuning structure includes at least one first metallic surface facing the resonator and at least one second metallic surface facing a wall of the cavity, the first and second metallic surfaces being conductively connected. The second metallic surface is arranged such that a small and essentially uniform gap is formed between the second metallic surface and the wall to achieve a virtual grounding of the metallic surfaces.

Abstract: Filter and manifold compensation assemblies for thermal compensation of a filter cavity and a manifold which include at least one a lever element pivotally coupled to the filter or manifold at a first pivot point, an anchoring element pivotally coupled to the lever element at the second pivot point and secured to the housing of the filter or manifold, and a thermal expansion element having a lower coefficient of thermal expansion than the filter cavity or manifold and pivotally coupled to the lever element. The relative thermal expansion of the thermal expansion element in comparison with the thermal expansion of the filter or manifold causes the lever element to articulate and to displace the housing for thermal compensation. The degree of each displacement is proportional to the ratio between the distance between the second and first pivot points and the distance between the second and the third pivot points.

Abstract: A magnetically-tunable filter comprising a filter housing with two tunable resonator spheres made of magnetizable material, which are disposed one above the other in two filter arms. At least one filter arm provides a fin line or slot line disposed on a substrate layer and extending in the direction towards an electrical contact, and a common coupling aperture, thereby connecting the two filter arms to one another. In this context, one resonator sphere is positioned within each filter arm on each of the two sides of the coupling aperture.

Abstract: The invention relates to a cavity filter comprising at least one tuning conductor (3) presenting a hollow portion (4), an isolation device (6) for a tuning conductor (3) of a cavity filter, and a node in a mobile communications network, comprising a cavity filter. According to the invention, the tuning conductor (3) comprises an isolation device (6) in a non-conductive material, which isolation device (6) is at least partly inserted into the hollow portion (4), and an insertion element (7) in a conductive material presenting a male thread (7a) that is engaged with an inner surface of the isolation device (6).

Abstract: Provided is an electromagnetic bandgap (EBG) structure, and particularly, an overlay EBG structure in which a plurality of vias and a plurality of plates are formed at intervals on a central signal line in such a manner that the vias and plates extend vertically from a substrate in order to reduce leakage loss of an electromagnetic wave through the substrate. Therefore, it is possible to prevent an electromagnetic wave passing through a transmission line from being lost through the substrate, to obtain desired frequency characteristics by adjusting the dimensions of the vias and plates, and to manufacture the overlay EBG structure using an existing CMOS process without having to perform any additional process.

Abstract: A frequency tunable filter comprises a housing having a plurality of walls therein defining a plurality of cavities; a cover mounted on the housing; a plurality of resonators contained in the cavities; at least one sliding member located between the cover and the resonators; and a plurality of metal tuning elements attached to a lower part of the sliding member, wherein frequency tuning is performed by sliding of the sliding member.

Abstract: The invention relates to a magnetically tunable filter having a filter housing and having two tunable resonator spheres which comprise magnetizable material and are arranged next to one another in two filter branches. Each filter branch comprises a coplanar line arranged on a substrate layer and extending in the direction of an electrical connection, as well as a common coupling opening so that the two filter branches are connected to one another. A resonator sphere is respectively positioned on each side of the coupling opening inside the two filter branches.

Abstract: An apparatus and a method are provided for electronically tuning cavity filters. A tunable cavity comprises at least two pieces of material, such as metal plates or metal traces, and MEMS circuitry interconnecting the pieces of material. Multiple tunable cavities can be combined to create a tunable cavity filter. In one embodiment, a waveguide cavity filter comprises a metal insert attached to a substrate. At least two pieces of material and MEMS circuitry reside within the cavities produced by the metal insert. The MEMS circuitry can be controlled to connect or disconnect the pieces of material, which alters the electric and magnetic fields inside the cavities. In another embodiment, a MEMS positioner inside the cavity filter can physically deform or move a piece of material within the cavity. By altering the electric and magnetic fields within the cavities the resonant frequency of the cavity filter can be tuned.

Abstract: This invention uses the structures of the finite-sized conductor-backed coplanar waveguides for designing broadband switchable and tunable signal filters. The design methods construct a plurality of configurations, which including waveguides, via holes, metallic posts, and conductor planes in the structures, for selecting, coupling, converting, and dissipating of the signals with specific electromagnetic modes and frequencies propagating through the structures. The dominant electromagnetic modes of the signals include Coplanar Waveguide Modes and Microstrip-Like Modes. The design methods thereby produce a plurality of filter types, such as bandstop filters, bandpass filters, multiband filters, etc. The design methods can apply to the structures with single and multi-layer dielectric and metallic materials, such as Integrated Circuits, Thin-film transistor Circuits, Low Temperature/High Temperature Co-fired Ceramics (LTCC/HTCC), PCB, and others.

Abstract: Tuning devices and methods are disclosed. One of the devices comprises a metal structure connected with artificial dielectric elements, and variable capacitance devices. Each variable capacitance device is connected with a respective artificial dielectric element and with a control signal. Control of the variation of the capacitance allows the desired tuning. Another device comprises metallic structures connected with artificial dielectric elements and switches connected between the artificial dielectric elements. Turning ON and OFF the switches allows the capacitance between artificial dielectric elements to be varied and a signal guided by the metallic structures to be tuned.

Abstract: A dielectric resonator filter having at least two poles for filtering a frequency band from an input frequency spectrum, which filter comprises (i) a body (2a, 2b) formed of electrically conductive material, which body (2a, 2b) defines a cavity (13) therein; (ii) a dielectric resonator element (1) enclosed in said cavity (13), (iii) a deformable member (6) located outside said cavity, and (iv) a metal member (4) located within said cavity (13) that is connected to said deformable member (6), the arrangement being such that, in use, said deformable member (6) is deformable to move said metal member (4) toward and/or away from said dielectric resonator element (1) to effect adjustment of a said frequency band.

Abstract: A switchable bandpass filter includes a coupled line segment (comb) including a plurality of coupled transmission lines of substantially equal lengths that are each connected or otherwise coupled to the common RF ground at their first end, a plurality of adjustable capacitors each coupled proximate a second end of respective ones of the transmission lines, and a plurality of shunt switches coupled to points along a length of each of the transmission lines. Shunt switches may be implemented by various device technologies including MEMS and FET switches and PIN diodes. The adjustable capacitors may be implemented as an array or tree of switched capacitors using suitable switching components (e.g., as previously enumerated) or by other suitable electrically controllable devices such as varactors or varactor arrays. A differential switchable filter may be formed by the symmetric repetition of individual bandpass filter modules.

Abstract: Waveguide nonlinear signal processors include transmission lines defined on a substrate. A plurality of varactors or pairs of varactors are situated along the transmission line and are in communication with a signal conductor of the transmission line and one or more control conductors. A processor controller is configured to provide a control signal to the one or more control conductors to select operational characteristics of the varactors or pairs of varactors. In some examples, the varactors are diodes and a control signal is provided to select a diode current-voltage characteristic in order to limit or clip an input signal to positive and/or negative amplitudes. Alternatively, a control signal is configured to provide a selected spectral transmission bandwidth or propagation delay by selecting a varactor capacitance-voltage characteristic.

Abstract: A method of fabricating a waveguide filter includes forming a monolithic polymeric dielectric core configured for fabricating a dielectric-filled cavity, where the core includes a plurality of spaced-apart depressions; applying a layer of conducting metal to an outer surface of the core to form a metallized core with a conductive metal layer, wherein the metal layer includes port openings at opposite ends of the metallized core, and wherein metallized depressions thereby formed are the ridges of the filter's ridge-waveguide sections; and mounting the metallized core on a supporting carrier. A desired number of such filters can be connected with an electrical-series-type connection among one port of each filter to form a frequency multiplexer having a waveguide manifold.

Abstract: The present invention relates to an improved tuning arrangement to linearise the sensitivity to frequency changes within a certain frequency range in response to tuner displacements relative to a resonator body. The tuning arrangement comprises a tuner and/or resonator having a non-uniform distribution of the effective dielectric permittivity along the axis of tuner displacement. The non-uniform distribution of the effective dielectric permittivity is realised by subdividing the tuner into an arbitrary number of sections, each of which distinguishable at least by their geometrical shape and the value and distribution of the dielectric coefficient ?r.

Abstract: A filter includes a waveguide with at least one impedance structure with a resonant frequency. The impedance structure is positioned in the waveguide to reflect signals at the resonant frequency. The filter can be tunable by including variable capacitance devices in the impedance structure(s) so that the resonant frequency can be adjusted.

Abstract: A wide-band fiber-optic tunable filter is provided. Dispersive polymers with different dispersion characteristics and side-polished fibers are used to fabricate wide-band tunable band-pass filters, band-rejection filters, short-wavelength-pass filters or long-wavelength-pass filters. This kind of wide-band fiber-optic tunable fiber filters is able to be used in the applications of fiber-to-the-home (FTTH) system networks. It is also able to be used in the applications of sensitive temperature sensors, high-resolution fiber refractometers, gain-flattened filters, fiber modal filters and fiber mode-field expanders/condensers.

Abstract: A tunable filter includes a waveguide with at least one resonant cavity and a tunable impedance structure coupled to each resonant cavity. Each resonant cavity has a resonant frequency and its corresponding impedance structure can be tuned to adjust the resonant frequency. The filter transmits the signal in a pass-band that includes the resonant frequency and reflects signals outside the pass-band.

Abstract: An electromagnetic filter assembly includes complimentary first and second blocks (1) and (2) defining two conjoined sections (10), (11) of an electromagnetic waveguide duct. A shim-like electromagnetic filter element (3) is held between the blocks and contains a series of holes (14) defining bridges (15) which traverse the waveguide duct to form poles of an electromagnetic filter. The filter element includes integral tuning projections (20) which extend into waveguide duct between the bridges. By adjusting the position of the filter element (3) between the blocks (1), (2) it is possible to vary the extent to which the tuning projections (20) project into the waveguide duct. The arrangement thus facilitates the repeated, continuous adjustment and variation of the electrical characteristics of devices such as filters, diplexers and multiplexers.

Abstract: A system and method for a plunger assembly includes a tuning slug with a bore in the stem, a tuning screw rotatably disposed in the stem, and a coupling assembly to rotatably secure the tuning screw to the slug. The system and method may also include a locking assembly to secure the postion of the assembly.

Abstract: A delay filter uses the dielectric mono-block triple-mode resonator and unique inter-resonator coupling structure, having smaller volume and higher power handling capacity. The triple-mode mono-block resonator has three resonators in one block. An input/output probe is connected to each metal plated dielectric block to transmit microwave signals. Corner cuts couple a mode oriented in one direction to a mode oriented in a second, mutually orthogonal direction. An aperture between two blocks couples all six resonant modes, and generates two inductive couplings by magnetic fields between two modes, and one capacitive coupling by electric fields. The input/output probes, coupling corner cuts and aperture are aligned such that all six resonators are coupled in the desired value and sign, so constant delay on the transmitted signal within certain bandwidth can be achieved. By connecting the input and output probes to the base printed circuit board, the delay filter is surface mountable.

Abstract: A tunable filter which may include at least one resonator. The at least one resonator may comprise a ring resonator made on a dielectric substrate placed in a waveguide, wherein the waveguide may contain a cut-off portion which houses and shields at least one resonator containing at least one tunable capacitor therein. A DC Bias circuit may be connected to the at least one resonator and may be capable of providing DC bias to the at least one tunable capacitor.

Abstract: A method of tuning the frequency response of filters embedded in or formed on a ceramic substrate, such as but not limited to a low temperature co-fired ceramic substrate (LTCC), by re-firing a previously fired LTCC substrate to a temperature which is greater by a predetermined, relatively small, amount than that of the temperature produced during the original firing profile of the substrate so as to change the dielectric constant of the substrate, and thus cause a desired shift in the filter's frequency response.

Abstract: A continuously variable waveguide attenuator (100). The continuously variable waveguide attenuator includes at least one waveguide attenuator cavity (109) having at least one barrier. A fluid dielectric (108) having a loss tangent, a permittivity and a permeability is at least partially disposed within the waveguide attenuator cavity (109). At least one composition processor (101 ) is included and adapted for dynamically changing a composition of the fluid dielectric (108) to vary an electrical characteristic of the fluid dielectric. A controller (136) is provided for controlling the composition processor (101 ) to selectively vary the electrical characteristic in response to a waveguide attenuator control signal (137).

Abstract: A system and method for a plunger assembly includes a tuning slug with a bore in the stem, a tuning screw rotatably disposed in the stem, and a coupling assembly to rotatably secure the tuning screw to the slug. The system and method may also include a locking assembly to secure the postion of the assembly.

Abstract: A variable waveguide system (100). The variable waveguide system (100) includes a waveguide (102), a dielectric structure (116) including at least one cavity disposed within the waveguide, and a conductive fluid (126). The cavity is filled with the conductive fluid (126) in a first operational state, and the cavity is purged of the conductive fluid (126) in a second operational state. A fluid control system (150) can be provided for transferring the conductive fluid (126) in and out of the cavity in response to a control signal (174). The waveguide (102) can have a first cutoff frequency in the first operational state and a second cutoff frequency in the second operational state. Further, the waveguide (102) can have a first electrical length in the first operational state and a second electrical length in the second operational state.

Abstract: A continuously variable waveguide filter (100). The variable waveguide filter can include at least one waveguide filter cavity (154, 156, 158) and a fluid dielectric (108) having a permittivity and a permeability at least partially disposed within the waveguide filter cavity (154, 156, 158). At least one composition processor (101) is included and adapted for dynamically changing a composition of the fluid dielectric (108) to vary at least one electrical characteristic. A controller (136) is provided for controlling the composition processor (101) in response to a waveguide filter control signal (137).

Abstract: A waveguide apparatus (100) includes a waveguide attenuator portion (102) having at least one waveguide cavity (109) and a conductive fluid (108) at least partially disposed within a waveguide cavity (104). At least one composition processor (101) is included and adapted for at least one among an electrical characteristic and a physical characteristic of the mode controlled waveguide by manipulating the conductive fluid to vary at least one among a volume, shape and a composition. A controller (136) is provided for controlling the composition processor in response to a waveguide mode control signal (137).

Abstract: A waveguide apparatus (100) and method (300) of mode control can include a waveguide structure (102) defining at least one cavity (116) disposed within the waveguide apparatus. The waveguide apparatus has at least a first operational state in which at least one cavity is filled with a conductive fluid (126) and at least a second operational state in which at least one cavity is purged of the conductive fluid. The waveguide apparatus can further include at least one composition processor (150) adapted for changing at least one among an electrical characteristic and a physical characteristic of the waveguide apparatus by manipulating a volume of the conductive fluid and a controller (172) for controlling the composition processor in response to a transmission line mode control signal (174).