Abstract: The present application describes a method of tuning a printed device. The method includes measuring a frequency response of a target device and a device under tune (DUT). The method includes computing, based on the measured frequency response, a coupling matrix for the target device and a coupling matrix for the DUT. The method also includes extracting eigenvalues for the coupling matrix of the target device and a first set of eigenvalues for the coupling matrix of the DUT. The eigenvalues of the target device are different than the first set of eigenvalues of the DUT. The method further includes tuning the DUT with a material removal source. The method even further includes measuring a second set of eigenvalues of the DUT. The second set of eigenvalues is different from the first set of eigenvalues of the DUT. The method yet even further includes calculating a tune path for iterative convergence of the second or a subsequent set of eigenvalues of the DUT with the eigenvalues of the target device.

Abstract: Apparatus and method for trapping RF on shields of a multiply shielded RF cable. In some embodiments, the RF trap shorts an outer conductor shield to an inner shield conductor of the cable successively at selected locations along an end length of the shield conductors. Some embodiments provide an RF-trap apparatus for blocking stray signals on a shielded RF cable that has two or more concentric peripheral shield conductors separated from one another by one or more electrically insulating layers, and at least one inner conductor for carrying RF signals. The RF trap apparatus includes: a first housing; and a plurality of projections configured be coupled to the first housing and to move to selectively electrically connect an outer shield conductor to an inner shield conductor by a pierce operation on the shielded RF cable.

Abstract: The present invention provides filter assemblies, tuning elements and a method of tuning a filter. A filter assembly includes a housing having a top cover, a bottom cover and at least one sidewall, the top cover, the bottom cover and the at least one sidewall defining an internal cavity, the housing configured to receive first through third radio frequency (“RF”) transmission lines; a top metal sheet mounted within the internal cavity that has a plurality of openings that form a first hole pattern; and a bottom metal sheet mounted within the internal cavity that has a plurality of openings that form a second hole pattern. The top and bottom metal sheets are vertically spaced-apart from each other in a vertically stacked relationship within the internal cavity. The top metal sheet and the bottom metal sheet each include at least one resonator.

Abstract: A method and a system (13) for evaluating a lower filter part (2) of a cavity filter including a bottom plate from which wall portions and at least one resonating element extend in an upward direction, wherein the method comprises: —scanning the lower filter part using a laser scanning assembly (14) to collect data relating to shapes and dimensions of the lower filter part, —comparing the collected data with reference data to determine whether the lower filter part fulfils predetermined quality requirements. A method for manufacturing a cavity filter includes evaluating a filter body of the lower filter part prior to assembling the cavity filter, wherein the step of assembling the cavity filter is only carried out if the filter body fulfils the predetermined quality requirements.

Abstract: In-line filters may include a tubular metallic housing defining a single inner cavity that extends along a longitudinal axis and a plurality of resonators that are spaced apart along the longitudinal axis within the single inner cavity, each resonator having a stalk. The stalks of first and second of the resonators that are adjacent each other are rotated to have different angular orientations.

Abstract: A resonant cavity filter has a housing having a resonator mounted therein, a tuning screw that comprises a head portion, a metallic tuning element and a dielectric spacer interposed between the head portion and the metallic tuning element. The tuning screw is mounted for coaxial insertion into an interior of the resonator to adjust a frequency response of the resonant cavity filter.

Abstract: The present disclosure is related to the microwave measuring field, and in particularly to a coaxial resonant cavity and system and method for measuring the dielectric constant of material. The coaxial resonant cavity includes a coupling mechanism and a cavity body. The coupling mechanism is accommodated in the cavity body for exciting or coupling microwaves inside the cavity body. The coaxial resonant cavity further includes a probe extending out of the cavity body and being coaxial with the cavity body. The cavity body is shaped as an annular column, and a ratio of an outer radius of the annular column to an inner radius of the annular column is (3-5):1. The present disclosure still provides a system and method for measuring the dielectric constant of material using the coaxial resonant cavity.

Abstract: A Capacitive Micromachined Ultrasonic Transducer (CMUT) device includes at least one CMUT cell including a first substrate having a top side including a patterned dielectric layer thereon including a thick and a thin dielectric region. A membrane layer is bonded on the thick dielectric region and over the thin dielectric region to provide a movable membrane over a micro-electro-mechanical system (MEMS) cavity. A through-substrate via (TSV) includes a dielectric liner which extends from a bottom side of the first substrate to a top surface of the membrane layer. A top side metal layer includes a first portion over the TSV, over the movable membrane, and coupling the TSV to the movable membrane. A patterned metal layer is on the bottom side surface of the first substrate including a first patterned layer portion contacting the bottom side of the first substrate lateral to the TSV.

Abstract: An electronic device may be provided with antenna structures. The antenna structures may be coupled to non-near-field communications circuitry such as cellular telephone transceiver circuitry or wireless local area network circuitry. When operated at non-near-field communication frequencies, the antenna structures may be configured to serve as one or more inverted-F antennas or other antennas for supporting far field wireless communications. Proximity sensor circuitry and near-field communications circuitry may also be coupled to the antenna structures. When operated at proximity sensor frequencies, the antenna structures may be used in forming capacitive proximity sensor electrode structures. When operated at near-field communications frequencies, the antenna structures may be used in forming an inductive near-field communications loop antenna.

Abstract: A coaxial cavity resonator filter has a hollow cavity and a post having desired dimensions for achieving desired filter characteristics. A tuning element is supported within a metallic opening and is configured to electromagnetically interact with the post. The tuning element has a conductive core element where the orientation of the tuning element with the cavity is adjusted so as to achieve the desired filter characteristic. An insulator is configured to cover a portion of the conductive core element of the tuning element, at a location where the tuning element and the metallic opening interact. A portion of the insulator is threaded so as to allow the conductive core element vary its orientation within the cavity without contacting the metallic opening.

Abstract: Embodiments relate to the field of technologies of components of communications devices, and provide a dielectric filter, which resolves a problem that a solid dielectric filter has a difficulty in implementing capacitive coupling. The dielectric filter includes at least two dielectric resonators, where each of the dielectric resonators includes a body made of a solid-state dielectric material, and an adjusting hole located on a surface of the body. The adjusting hole is a blind hole, configured to adjust a resonance frequency of the dielectric resonator on which the blind hole is located. The bodies of all the dielectric resonators included by the dielectric filter form a body of the dielectric filter.

Abstract: A coaxial tunable band stop filter utilizes tuning elements, such as PIN diodes and varactor diodes, for electrically tuning a coaxial resonator to change the resonance frequency of the coaxial resonators. A voltage is applied to the tuning elements to change their capacitance, such that they electrically lengthen and shorten the coaxial resonator. The variable voltages work to change the center frequency across a bandwidth. When the resonators are electrically extended or shortened in length, the center frequency in the bandwidth is changed accordingly. The bandwidth for the coaxial tunable band stop filter is tunable to increase and decrease based on the position of the center frequency. A ninety degree transmission line is used for coupling the components of the filter. A digital control is used for manipulating the tuning elements.

Abstract: A filter capable of adjusting frequency and bandwidth for dynamically setting at least one of the filter center frequency and bandwidth includes a first movable member, a second movable member, an upper casing, a lower casing, multiple conductive clamping members, a cavity and a driving module. The first and second movable members have multiple first and second lugs formed on the first and second boards respectively. The upper and lower casings have multiple upper and lower openings corresponsive to the first lugs and the second lugs respectively. The conductive clamping members are corresponsive to the upper openings and the lower openings. The cavity has multiple chambers and multiple connecting portions. The driving module changes the position of the first movable member to determine the filter center frequency and the position of the second movable member to determine the bandwidth.

Abstract: A tunable filter for dynamically setting a filter center frequency includes a movable member, an upper casing, a lower casing, conductive gaskets, a cavity and a driving unit. The movable member includes a board and lugs. The upper casing includes upper openings corresponsive to the lugs respectively. The lower casing includes lower openings corresponsive to the upper openings respectively. The conductive gaskets are disposed between the upper and lower casings. The cavity is combined with the lower casing and has chambers, and the conductive gaskets are corresponsive to the upper and lower openings respectively. The driving unit is coupled to the movable member for moving the lugs in a first direction towards the chambers or in a second direction away from the chambers. The distance moved by the lugs in the first direction or the second direction is used for determining the filter center frequency.

Abstract: The present application provides a dielectric resonator, a dielectric filter, a base station and a method for fabricating the dielectric resonator or the dielectric filter. The dielectric resonator includes: a solid dielectric resonator body, a blind hole located on one side of the solid dielectric resonator body, a metalized layer covering both a surface of the solid dielectric resonator body and a surface of the blind hole, and a demetallized notch located at the metalized layer on the surface of the blind hole. The dielectric resonator provided in the present application can implement tuning of the dielectric resonator, and reduce impact on the resonance frequency of the dielectric resonator after the dielectric resonator is tuned, where the impact caused by that the demetallized notch is covered by a metal material in an assembly process of the dielectric resonator, and signal energy that is leaked from the notch is reduced.

Abstract: The present invention relates to a radio frequency filter having a cavity structure, comprising: a container which has a hollow inner portion and a cavity that is cut off from the outside, and a resonance element which is placed in the hollow inner portion of the container, wherein the container has a wrinkled structure for adjusting the intervals between a longitudinal front end surface of the resonance element and the inner surfaces of the container facing the longitudinal front end surface using external pressure. Thus, the invention can be further miniaturized and is lightweight, and the design of the invention enables frequency tuning without employing a coupling structure of a tuning screw and a fastening nut, thereby obtaining a convenient and simplified structure.

Abstract: The present invention relates generally to digital elliptic filters, and more particularly, but not exclusively to multi-layer digital elliptic filters and methods for their fabrication.

Abstract: A tunable diplexer includes a high pass filter, a low pass filter, a high band port, a low band port, and an antenna port. The high pass filter is adapted to pass high band signals falling within a high pass band between the high band port and the antenna port, while attenuating signals outside of the high pass band. The low pass filter is adapted to pass low band signals falling within a low pass band between the low band port and the antenna port, while attenuating signals outside of the low pass band. The low pass filter includes a low stop band zero, which is adapted to attenuate signals within a low stop band. The low stop band zero is tunable, such that the low stop band can be adjusted to selectively attenuate signals within a given frequency band in the low pass band.

Abstract: A cavity filter includes a slider, a driving device, and an adapter. The slider is used to slide relative to and couple with a plurality of resonators located in the cavity filter to adjust a resonating frequency of the cavity filter. The driving device is used to drive the slider slide relative to the plurality of resonators and includes a shaft having a free end. The adapter is installed between the slider and the driving device and rotateably connected to the free end of the shaft with a gap configured between the free end and the adapter.

Abstract: A cavity filter includes a slider, a driving device, an adapter and a resilient member. The slider is used to slide relative to and couple with a plurality of resonators located in the cavity filter to change a resonating frequency of the cavity filter. The driving device is used to drive the slider slide relative to the plurality of resonators. The adapter is installed between the slider and the driving device. The resilient member is elastically connected between the slider and the adapter and used to absorb vibrations of the driving device to make the slider move on an even keel.

Abstract: A radio frequency (RF) filter includes an input port configured to receive a signal, an output port configured to output a signal, and a tuning probe configured to be movable within a tuning probe port to adjust filter characteristics. The tuning probe port is configured to receive the tuning probe therein, and a locking mechanism is configured to lock the tuning probe in the tuning probe port at a desired depth and further configured to prevent movement of the tuning probe in the tuning probe port when the locking mechanism is in a locked configuration.

Abstract: A dielectric core tunable filter for microwave frequencies of 0.5-30 GHz. The filter includes a low loss machined dielectric having multiple channels a portion of which are terminated in micro-electromechanical variable capacitors to realize coupled resonators. The machined dielectric is metalized with a material, such as copper, silver, or gold, and then patterned to provide ring shaped recesses at the ends of preselected channels.

Abstract: The invention discloses a high-frequency filter in coaxial design which allows a simple option for tuning resonators contained in the high-frequency filter. In order to tune the resonator(s), a first tuning element is mechanically anchored in the second terminating wall such that the element is rotationally fixed and the axial length thereof cannot be varied, and a second tuning element, the position of which can be varied, is provided in the longitudinal opening of the inner conductor, wherein the second tuning element consists of a dielectric material, or comprises dielectric material, at least in the region facing the second outside wall, wherein the axial position of the second tuning element can be varied in the spacing area between the inside face of the inner conductor and the first tuning element. The second tuning element can be accessed and/or actuated from the outer side of the first terminating wall to effect a variation of the axial position.

Abstract: A cavity filter having a piezoelectric tuning element is tuned by determining a desired oscillating frequency for the piezoelectric tuning element and applying that frequency through a phase-locked loop. The phase-locked loop maintains the piezoelectric tuning element at the desired frequency.

Abstract: A tuneable resonator filter consisting of cavity resonators. In the partition wall separating the successive resonators on the transmission path of a resonator filter there is a coupling opening (CPO) with a typically constant width. The coupling strength between the resonators is adjusted by a tuning element which is supported to the partition wall on the opposite sides of the coupling opening so that it can be moved. The tuning element is conductive and grounded so that the impedance between its ends and the partition wall is low. For moving the tuning element, it is linked by a dielectric rod to an electrically controllable actuator being located on the filter lid. By means of the tuning mechanism the bandwidth of a filter can be set automatically.

Abstract: An adjustable resonator filter comprised of cavity resonators. There is a movable conductive tuning element in the filter for adjusting each electromagnetic coupling, which element is located outside the resonator cavities. When the coupling between two resonators is the case, the movement of the tuning element changes the coupling between the signal ground and a fixed coupling element which extends from a resonator cavity to the next cavity, whereupon the strength of the coupling between the resonators changes. When the coupling between a resonator and the input/output line of the filter is the case, by means of the tuning element it is implemented a section with a low impedance inside a range with a relatively high impedance on the transmission path. This section moves together with the tuning element, in which case the strength of the coupling between the resonator and the line changes.

Abstract: A coaxial cavity resonator filter has a hollow cavity and a post having desired dimensions for achieving desired filter characteristics. A tuning element is supported within a metallic opening and is configured to electromagnetically interact with the post. The tuning element has a conductive core element where the orientation of the tuning element with the cavity is adjusted so as to achieve the desired filter characteristic. An insulator is configured to cover a portion of the conductive core element of the tuning element, at a location where the tuning element and the metallic opening interact. A portion of the insulator is threaded so as to allow the conductive core element vary its orientation within the cavity without contacting the metallic opening.

Abstract: A high-order harmonic device of a cavity filter including a base and a lid cover the base is disclosed. The base has a through groove connecting to an upper and a lower portion. The base has a plurality of output terminal with metallic conductor extending into the inner side formed on the surface of the sidewall. The base has resonance space formed indented to receive the metallic conductor and extending to connect to the through groove. The lid has a plurality of threading holes formed corresponding to chambers and partitions received with adjusting elements for height adjustment. The adjusting elements has the resonance bars corresponding to every chamber and the suppressing bars corresponding to every partition. By adjusting suppressing bar and the partition to a predetermined distance, the space of the channel for transmitting the high-order harmonic wave can be reduced to suppress noise produced by high-order harmonic wave.

Abstract: The invention discloses a high-frequency filter in coaxial design which allows a simple option for tuning resonators contained in the high-frequency filter. In order to tune the resonator(s), a first tuning element is mechanically anchored in the second terminating wall such that the element is rotationally fixed and the axial length thereof cannot be varied, and a second tuning element, the position of which can be varied, is provided in the longitudinal opening of the inner conductor, wherein the second tuning element consists of a dielectric material, or comprises dielectric material, at least in the region facing the second outside wall, wherein the axial position of the second tuning element can be varied in the spacing area between the inside face of the inner conductor and the first tuning element. The second tuning element can be accessed and/or actuated from the outer side of the first terminating wall to effect a variation of the axial position.

Abstract: A re-entrant resonant cavity 12 includes a first metallized molded plastic component 18, which comprises a re-entrant stub 17, an end wall 14 and a cylindrical side wall 13. The component 18 is surface mount soldered to a metallized PCB substrate 19. A rostrum 24 is located facing the end face 21 of the stub 17 to define a capacitive gap 22 with it. The end face 21 of the stub 17 and the rostrum 24 are configured such that relative rotation between them changes the profile of the gap 22 and hence the gap capacitance. By suitably locating the two parts during manufacture, a particular capacitance may be chosen to give a desired resonance frequency from a selection available depending on the relative angular position of the stub 17 and rostrum 24. In another cavity, the rostrum is replaced by an etched metallization layer of a printed circuit board.

Abstract: A cavity filter includes an enclosure, resonators secured inside the enclosure, a lid, a slider, and a driving device. The enclosure includes a bottom portion, sidewalls extending from edges of the bottom portion to define a cavity. Each sidewall defines a positioning portion at a top surface thereof. The lid covers the enclosure. The slider includes tuning cells each partially coated with metal and positioned opposite to one of the resonators. The slider is movably disposed between the lid and the resonators and slides on the positioning portions. The driving device is located inside the enclosure and drives the slider to move along the positioning portions to adjust a resonating frequency of the cavity filter.

Abstract: An adaptable filter made up of cavity resonators. The adaptation takes place by adjusting the connection from the input connector (CN1) of the filter to the input resonator and from the output resonator to the output connector. For adjusting the connection there is a coaxial transfer line (TL1), the outer conductor (OC1) of which is connected by its one end to the wall of the filter casing and by its other end to the outer conductor of the connector (CN1) and the inner conductor of which extends from the middle conductor of the connector to the cavity of the resonator and there into the internal connecting member of the resonator. A middle rod belonging to the inner conductor is surrounded over a certain distance by a cylindrical conductive tuning element, which can be moved by sliding it along the middle rod.

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: 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 resonator is provided with a tuning element based on piezoelectricity. The piezoelectric basic element includes at least one piezoelectric layer and a metal layer. Such a basic element is first coated with a thin insulating layer and then with a good conductor. The thickness of the conductive coating is greater than the skin depth of a field corresponding to the operating frequency of the structure in the conductor. The tuning element formed in this manner is fastened on, e.g., some inner surface of the resonator cavity and acts to change the natural frequency of the resonator by electric control. When using the tuning element, no mechanical arrangement is required for moving the tuning element. Furthermore, the tuning element does not cause considerable dielectric losses nor intermodulation when being in a radiofrequency electromagnetic field, because the field cannot significantly penetrate through said conductive coating into the piezoelectric material.

Abstract: An embedded resonator sharpens the frequency characteristics of a coaxial low pass filter. The resonator introduces finite transmission zeros to the response of the low pass filter, thereby suppressing spurious modes occurring just above the operating frequency. Two parameters are used to tune the operation of the embedded resonator. The length of an insert into the filter's transmission line substantially controls the resonant frequency, and the gap width substantially controls the coupling of the embedded resonator to the low pass filter.

Abstract: An inline microwave bandpass filter where cross coupling between non-adjacent resonators is realized by changing the orientation of selected resonators. The microwave bandpass filter includes a cavity and three or more resonators arranged in a row (or inline) in the cavity. At least one resonator has a different spatial orientation from at least one other resonator. For example, one or more of the resonators may be rotated 90 or 180 degrees with respect to one of the other resonators. This arrangement of resonators facilitates sequential coupling between pairs of adjacent resonators and cross coupling between at least one pair of non-adjacent resonators without the use of additional cross coupling structures such as dedicated coupling probes or extra cavities. One or more plates may be introduced between adjacent resonators to independently control the sequential and cross coupling.

Abstract: A radio frequency filter comprising: housing body having input/output connectors and containing space which is divided into spaces by means of diaphragm; at least one resonator rod arranged in the housing; housing cover coupled to the housing body; wherein the housing body and the housing cover are coupled to each other by laser welding. The radio frequency filter according to the present invention can reduce PIMD due to reduce Contact Nonlinearity, and inhibit to erode away because the laser welding method dissolve different metallic materials each other and take a convalent bond, and reduce its manufacturing process time and cost because it is unnecessary drilling a hole and fastening a screw to fasten the housing and the housing cover each other and can simplify its manufacturing process and raise productivity because only irradiate laser beam on irradiated area of the housing cover.

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: The signal to noise ratio performance of a RF communication system can be improved by providing resistance to transmitter self-jamming and eliminating or reducing the need for a transmit rejection filter or other measures such as limiters or blanking switches. An anti-jam low noise amplifier provides enough rejection and jamming immunity to reduce or eliminate the need for the transmit reject filter. Thus, the system noise performance is improved by eliminating the filter and the associated losses which cause signal to noise ratio performance degradation.

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: A method for fabrication of a filter includes forming an input transformer pole in a first substrate by forming a first conductive via, forming an output transformer pole in the first substrate by forming a second conductive via, forming one or more filter poles in the first substrate between the input transformer pole and the output transformer pole by forming one or more conductive vias in the first substrate between the input transformer pole and the output transformer pole, fabricating one or more tuning elements on a second substrate, wherein the number of tuning elements corresponds to the number of filter poles between the input transformer pole and the output transformer pole, and bonding the second substrate to a top surface of the first substrate so that each tuning element on the second substrate is aligned with and overlays a filter pole on the first substrate.

Abstract: A metamaterial device has a coaxial structure including rotational symmetry about a longitudinal axis of coaxial conductors. In a disclosed example, a series inductance portion has a relatively smaller circumferential dimension compared to another portion of a conductor. A series capacitance portion comprises an interruption in the conductor. A shunt capacitance portion has the largest circumferential dimension of the conductor. A shunt inductance portion comprises a relatively small electrical connection between first and second conductors. A disclosed example metamaterial structure is useful, for example, as a filter in a wireless communication device.

Abstract: A variable radio frequency band filter capable of varying the resonance frequency band comprises a housing having a support; a number of resonator rods arranged along the longitudinal direction of the housing; at least one tuning rod positioned on top of the resonator rods; a tuning support extending through the respective tuning rods along the longitudinal direction of the housing and adapted to slide on top of the respective resonator rods to vary the position of the tuning rods; and a frequency variation unit positioned on a lateral surface of the housing. The frequency variation unit being coupled to an end of the tuning support and adapted to vary the position of the tuning rods, as the tuning support is slid, according to the frequency band.

Abstract: A fixed or tunable resonator. The resonator includes an inner conductor, a hollow outer conductor, and a hollow insulating layer. The hollow outer conductor forms a first inner space. The hollow insulating layer is formed from an outer soft dielectric layer, an inner soft dielectric layer, and a ceramic layer disposed between the soft dielectric layers. The hollow insulating layer includes a second inner space formed by the inner soft dielectric layer. The inner conductor is disposed within the second inner space of the hollow insulating layer, and the hollow insulating layer is disposed within the first inner space of the hollow outer conductor.

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: An improved high frequency filter in a coaxial construction with one or a plurality of resonators has a thread pitch or thread pitch angle of an external thread of a thread-like tuning element which differs from the thread pitch or the thread pitch angle of the internal thread of the thread receiver at least in a partial portion of the length of the internal thread and/or of the external thread. The difference between the thread pitches or the thread pitch angles between the external thread of the thread-like tuning element and the internal thread of the thread receiver is more than 0.5%, and preferably 1% to 5%.

Abstract: There is provided a filter characteristic adjusting apparatus and a filter characteristic adjusting method which can avoid an increase in circuit scale of the filter characteristic adjusting apparatus, and can speedily adjust a characteristic frequency of the filter to a desired frequency. When performing characteristic adjustment for the filter, the test signal generation unit (31) generates a test signal (s14) which is a pulse signal having the same frequency as the characteristic frequency of the filter (10) on the basis of a reference signal (s17), and a phase-shifted test signal (s14?) that is obtained by shifting the phase of the test signal (s14) by a predetermined amount with a phase shift unit (32) in a control signal generation unit (33) is compared with a filter output signal (s16) that is obtained by inputting the test signal (s14) into the filter (10) to obtain a phase difference between the signals, and then the phase difference is subjected to a binary search to generate a control signal (s11).

Abstract: A stable and reliable built-in cross-coupled dielectric filter with temperature-independent performances and improved rectangular degree and amplitude-frequency characteristic is disclosed. The built-in cross-coupled dielectric filter comprises at least three sequentially welded coaxial dielectric resonators. Mutually coupled capacitors or mutually coupled inductors are etched on the two adjacent lateral surfaces of the adjacent coaxial dielectric resonators, respectively, with an alternate setup. The input and output ports of the built-in cross-coupled dielectric filter are positioned at the two coaxial dielectric resonators at the head and tail, respectively. The present invention is particularly applicable to the high-frequency realm such as microwave.

Abstract: The invention relates to a tunable ?/4-filter subassembly (10) whose frequency response can be adjusted. For this purpose, the ?/4-filter subassembly (10) has a signal-conducting electrical conductor (20) and an electrically conductive element (30) that is at a reference potential. Furthermore, at least one short-circuit device (40; 140) is provided that electrically contacts the electrical conductor (20; 120). An electrical coupling device (70; 170) is provided that couples the short-circuit device (40; 140) at a settable contact position (80; 180) to the electrically conductive element (30; 130), wherein the electrical coupling device (70; 170) and the short-circuit device (40; 140) are movable relative to each other in order to set the length of the short-circuit device (40; 140).