Abstract: A coupler for coupling RF electromagnetic energy into or out of a resonant cavity of the type which includes a control post.

Abstract: A coaxial cavity resonator is described. The resonator includes a tapered inner conductor for increasing the Q of the cavity.

Abstract: The present invention relates to a fastener means for securing a center conductor (23) in a cavity filter and for enabling the center conductor to be secured mechanically in a stable fashion and with good electric contact between itself and the bottom 22 of the cavity. The inventive fastener means comprises a center conductor and a fastener element (25, 26) provided integral therewith to form a single-piece structure, which structure may have the form of a screw with the center conductor (23) as the screw head at one end and screw threads (26) at the other end. The contact surface between the fastener means and the cavity bottom is surface-treated with a material of low resistivity, such as silver for example.

Abstract: A dielectric filter comprising a dielectric block having a substantially rectangular solid shape and having an outer-conductor; a plurality of inner-conductor-coated holes disposed inside the dielectric block; the end portion of at least one inner-conductor-coated hole being an open-circuited surface on which the outer-conductor is not disposed, and an input-output electrode being capacitance-coupled to the vicinity of the end portion of that inner-conductor-coated hole; and both end portions of another inner-conductor-coated hole, which is not capacitance-coupled to an input-output electrode, are covered by the outer-conductor, and an inner-conductorless portion is provided inside the hole. Preferably an end portion of the other hole either is sunken below or protrudes above the open-circuited surface.

Abstract: A multimode dielectric resonator apparatus is configured such that a TM mode and a TE mode are transformed into multiplex modes, coupling between individual resonant modes can be easily made, and a large number of sequentially coupled stages for a single dielectric core can be obtained. A dielectric core is configured of a plate-like TM-mode dielectric core portion and a TE-mode dielectric core portion protruding therefrom asymmetrically in the upper and lower directions. By this asymmetry of the TE-mode dielectric core portion with respect to the TM-mode dielectric core portion, for example, a TMx mode and a TEz mode may be coupled together, and concurrently, a TMy mode and a TEz mode may be coupled together.

Abstract: There is a manufacturing limit on how small ceramic coaxial resonators can be produced, which leads to a limit on the frequency of resonance for these resonators. One technique to double the effective frequency of a ceramic coaxial resonator is to couple each end of a resonator to a Colpitts oscillator, the oscillators being balanced and out-of-phase by 180°. During operation, the resonator is effectively divided in half with a virtual ground forming in the center. This allows a single resonator to operate as two resonators of half the original size. Hence, the oscillation frequency for each of these balanced oscillators is doubled when compared to the frequency of similar oscillators that have separate ceramic coaxial resonators of similar size. If this technique is further implemented within a push-pull design tuned to the third harmonic, the output oscillation frequency becomes six times that of an oscillator using a separate ceramic coaxial resonator of similar size.

Abstract: The invention provides a coaxial resonator which can be electrically connected to an inductance or like electric element easily to reduce the number of work steps for mounting and the number of parts, and a dielectric filter and a dielectric duplexer which comprise the resonator and which can be compacted and installed in a diminished space. The coaxial resonator comprises a dielectric block having a through bore extending through opposite end faces thereof, and a conductor layer formed over an outer peripheral surface of the block except one end face thereof and over a block inner surface defining the through bore for causing electromagnetic waves to resonate within the dielectric block. A lead-equipped electric element has its lead inserted in the through bore and electrically connected to the conductor layer over the bore-defining inner surface with a braze filler metal or electrically conductive adhesive, the lead being fixed in the through bore.

Abstract: A ceramic block filter is designed with a shunt transmission line to attenuate third harmonics. A metallized belt is printed on the top surface of the filter along its edges so that it is connected to the metallized ground of the side surfaces. Along one edge an unmetallized line is left along one edge of the filter, whose ends are grounded. The unmetallized line is designed with a length greater than one-half of the length of the metallized belt, but smaller than the length of the metallized belt. The length and width of the unmetallized line are design choices for the specific frequencies sought to be attenuated.

Abstract: The construction is a coaxial cavity resonator (20, 30, 40, 50) comprising at least one conductive body (11, 31), which body is open at one end and shortened from a quarter-wave resonator. The conductive body includes a main rod (16), which is in one end attached to the cavity wall (15), and a main disc (17) attached to the free end of the main rod (16). The cavity (12) further comprises one or more conductive plates (21, 41, 51) located between the main disc (17) and the side walls (13), at the first side (17a) of, and out of galvanic contact with, the main disc (17). The shortening is carried out by creating air-insulated extra capacitance between the resonator cavity walls via the conductive plates and a mechanical structure at the open end of the conductive body.

Abstract: There is provided a dielectric filter comprising: a dielectric block; a plurality of resonance lines aligned substantially in parallel in the dielectric block; and a conductor line disposed in the dielectric block so as not to be parallel to the longitudinal direction of the resonance lines, the conductor line being served as a device having an inductance component which is connected to a circuit comprising the resonance lines.

Abstract: A duplexer comprising: &lgr;/4-type dielectric coaxial resonators constituting a transmitting-side filter; &lgr;/4-type dielectric coaxial resonators constituting a receiving-side filter; and coupling elements for coupling said resonators; wherein the dielectric coaxial resonators constituting the transmitting-side filter and the dielectric coaxial resonators constituting the receiving-side filter are placed in parallel; and the open end surfaces of the dielectric coaxial resonators constituting the transmitting-side filter and the open end surfaces of the dielectric coaxial resonators constituting the receiving-side filter are disposed in opposite directions, and/or are alternately disposed side-by-side.

Abstract: The invention comprises a filter consisting of resonators (330, 320, . . . ) with a conducting housing, particularly to be used in networks operating on microwave frequencies. The couplings between the resonators are realised outside the conducting filter housing with the aid of a printed board (310) over a wall (306) of the housing. For a particular coupling a conductor strip (311) extending from one resonator to another is formed on the printed board, and openings (335, . . . ) are made in the resonator walls at the ends of the strips. In order to strengthen the coupling a coupling element (343) extending into the resonator cavity can be fastened as an extension of the strip. The filter connectors (301, . . . ) are also fastened to the printed board. The open filter housing (305) and the inner conductors (331, 341, . . . ) or the resonators can be made as a homogenous body. The manufacturing costs and the tuning costs of a filter according to the invention are relatively low.

Abstract: A multi-resonator filter, including a housing, at least one resonating element, at least one high dielectric constant element, at least one fine tuning screw located above the at least one resonating element and secured in a housing cover by a locking nut, housing screws to secure the housing cover to the housing. Where at least two resonating elements and at least two high dielectric constant elements are present, at least two slots are located in the at least two high dielectric constant elements to allow the easy installation and removal of at least one high dielectric coupling bridge used to increase the coupling between resonator sections, and at least one coupling probe.

Abstract: The present invention provides a dielectric resonator, a dielectric filter, a dielectric duplexer capable of reducing leakage of electromagnetic waves and capable of being miniaturized, and a communication apparatus incorporating the same. In each of the dielectric resonator and filter, inside a dielectric block, there is formed a L-shaped inner-conductor-formed hole having a bend at some point of the hole in a manner extending from an outer surface of the dielectric block to a surface perpendicular to the outer surface. An inner conductor is formed on the inner surface of the inner-conductor-formed hole. On the substantially entire outer surfaces of the dielectric block, there is disposed an outer conductor, with one end of the inner-conductor-formed hole open-circuited and the remaining end of the hole short-circuited. Around the edge of the open-circuited end there is formed an outer coupling electrode.

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and a through-hole is formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-hole as well as the outside dimensions of the dielectric block. A terminal electrode is formed on the outer surface of the dielectric block, for example at an end surface. A coupling hole is formed in the dielectric block and a coupling electrode is formed on the inner surface of the coupling hole. One end of the coupling electrode is connected to the terminal electrode and the other end of the coupling electrode may be connected to the conducting film formed on the outer surface of the dielectric block, for example at a side surface. The coupling electrode is non-linear, preferably L-shaped.

Abstract: A high-frequency dielectric ceramic compact is provided which has a relative dielectric constant (∈r) of about 20 or less and a Q value of about 20,000 or more at 1 GHz, in which the temperature coefficient (&tgr;f) can be optionally controlled at about 0 (ppm/° C.). When the compact of the dielectric ceramic compact is represented by the formula aBaO.bMeO.cSbO3/2, 0.476≦a≦0.513, 0.160≦b≦0.175, and 0.324≦c≦0.350. In addition, when the compact of the dielectric ceramic compact is represented by the formula dBaO.eMeO.fSbO3/2.gTiO2, 0.476≦d≦0.513, 0.100≦e≦0.175, 0.200≦f≦0.349, and 0<g≦0.200.

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and a through-hole is formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-hole as well as the outside dimensions of the dielectric block. A terminal electrode is formed on a side surface of the dielectric block. A coupling hole is formed in the dielectric block and a coupling electrode is formed on the inner surface of the coupling hole. One end of the coupling electrode is connected to the terminal electrode and the coupling electrode extends toward the conducting film formed on the opposite side surface and one end surface of the dielectric block. The above structure allows an increase in the degree of freedom in the design of the characteristics including the resonance frequency and unloaded Q of the dielectric waveguide resonator.

Abstract: The invention relates to a method for attaching an additional object to an object made by the process of extruding, especially a resonator body, and to the structure resulting from the application of the method. A recess is made in the pushing part (ES) of an extrusion machine, which recess is shaped like a portion of the surface of the additional object. The additional object (320), such as a portion of the inner conductor of a resonator, is inserted prior to extrusion in the said recess so that the said portion of the surface of the additional object rests tightly against the surface of the recess and the rest of the surface of the additional object remains free. In the extrusion stage, the pushing part with the additional object is pressed (F) against a bloom of a resonator body whereby the material (31c) of the bloom is pressed tight against the free surface of the additional object. When the pushing part is retracted the additional object remains attached to the body element thus formed.

Abstract: There is provided an antenna duplexer, comprising: a plurality of resonance electrodes constituting a transmission filter and a reception filter; a dielectric member disposed betwee:n the resonance electrodes and a ground electrode; a transmission terminal, a reception terminal, and an antenna terminal, which are separated from the ground electrode in the region where the ground electrode is formed; at least one ol the transmission terminal and the reception terminal provided to make capacitive coupling between the resonance electrode of a first stage corresponding to ani In/Out stage and the resonance electrode of a second stage adjacent to the resonance electrode.

Abstract: There is a manufacturing limit on how small ceramic coaxial resonators can be produced, which leads to a limit on the frequency of resonance for these resonators. One technique to double the effective frequency of a ceramic coaxial resonator is to couple each end of a resonator to a Colpitts oscillator, the oscillators being balanced and out-of-phase by 180°. During operation, the resonator is effectively divided in half with a virtual ground forming in the center. This allows a single resonator to operate as two resonators of half the original size. Hence, the oscillation frequency for each of these balanced oscillators is doubled when compared to the frequency of similar oscillators that have separate ceramic coaxial resonators of similar size.

Abstract: A coaxial resonator according to an embodiment of the invention includes a tubular dielectric block, an inner conductor having a thin-film, multi-layer electrode structure, which is formed on an outer surface of a cylindrical shaft received in the hole of the tubular dielectric block, and an outer conductor formed on an outer surface of the tubular dielectric block. The cylindrical shaft is inserted into the hole in the dielectric block, and is held by a holding member and an outer frame.

Abstract: The present invention provides a high frequency dielectric filter which can realize high stability, the least loss of functionality, and mass-productiveness. In a high frequency dielectric filter adopting a TM mode, a resonator fixing plate 3 is used for fixing a dielectric resonator 2 and a case 1 and hence, they are firmly fixed both in the longitudinal direction and the lateral direction of the resonator. Accordingly, a high frequency dielectric filter which is stable against vibration and impact is provided.

Abstract: A resonator or a filter consisting of resonators comprises an inner conductor or conductors and an outer conductor enclosing the inner conductor or conductors. It comprises a first part (201, 301, 401, 604, 701) and a second part (202, 302, 420, 501, 605, 702), of which the first part comprises at least a part of the inner conductor or conductors (203, 303, 402, 404, 703, 704, 705, 706, 707) and a part of the outer conductor (204, 205, 304, 305, 405, 406, 407, 408, 409), which is integral with the inner conductor parts and made of the same material, and of which the second part comprises such a part of the outer conductor (206, 207, 304, 305, 421, 422, 423, 424, 425) which, when connected to the first part, forms a continuous outer conductor enclosing the inner conductor.

Abstract: A dielectric resonator device in which resonant electrodes are provided in or on a dielectric block, and another ground electrode is formed on an outer face of the dielectric block. Lengths of the resonant electrodes are determined according to desired resonance frequencies of the respective resonators, while widths of gap regions in the through-holes having no electrodes are determined according to the desired amounts of coupling between the respective resonators. Since the dielectric block may be standardized, various kinds of dielectric resonator devices having different characteristics can be obtained without increasing the required numbers of kinds of molding metal molds.

Abstract: A method and apparatus for frequency stabilization of cavity filters of the class including an outer tubular conductor and an inner conductor is effected by supporting the inner conductor of the resonant cavity by an apparatus comprised of a reference collar and an interface collar connected together by a means having a first coefficient of thermal expansion. The reference collar is structurally connected to the reference end of the outer tubular conductor by adjustable tuning means. It is not connected directly to the inner conductor. The inner conductor is structurally connected to the interface collar by a means having a second coefficient of thermal expansion. The first coefficient of thermal expansion and the second coefficient of thermal expansion are selected to provide compensation for the difference in thermal expansion between the outer conductor and the inner conductor of the cavity filter.

Abstract: The present invention relates to a coaxial cavity resonator comprising walls delimiting a cavity, and one resonator body comprising a conductive rod having a first end being in short circuit relation to a first wall of the cavity walls, the first end having a cross-sectional area. The resonator further comprises a first conductive supportive plate having a first side being connected to the first end of each rod, the first side having a larger area than the cross-sectional area of the first end of the rod and a second side, opposite the first side, of the supportive plate being electrically connected to the first wall. A retainer is provided in the first cavity wall to guide the supportive plate, and an attachment is provided to secure the first supportive plate to the retainer. The invention also relates to a filter and a use of a resonator component in a filter.

Abstract: There is a manufacturing limit on how small ceramic coaxial resonators can be produced, which leads to a limit on the frequency of resonance for these resonators. One technique to quadruple the effective frequency of a ceramic coaxial resonator is to couple four resonators into a ring configuration, each of the resonators having an electrical length of 90°. Further, each of the resonators has an amplifier coupled in parallel, these amplifiers having phase shifts approximately equal to 90° and further being controlled by a tuning voltage VTUNE. In operation, four oscillation signals are generated at the same frequency but out-of-phase by a factor of 90°. When combined, the resulting signal is an oscillation signal at four times the frequency of the original oscillation signals. At the same time, one of the oscillation signals used in the combination can be sampled and be used for feedback purposes within a PLL-FS.

Abstract: A dielectric filter includes a dielectric block having multiple through holes which are created in parallel and grooves which are created around the opening of the through holes. A conductor is formed inside the grooves and the through holes. The inside conductors and in-groove conductors are connected at the opening of the through hole surrounded with the groove. The inside conductors and an outside conductor are connected at a second end. The opening of the through hole is formed inside an open-circuit end of the dielectric block.

Abstract: A dielectric filter including at least three coaxial dielectric resonators of predetermined size which are bonded as arranged side by side. The resonators serving respectively as an input stage and an output stage are each formed with an external connection electrode positioned on the peripheral surface other than the adjoining surface in proximity to an exposed end face and insulated from an outer conductor layer. An inner conductor layer of the resonator serving as an intermediate stage is removed over only a suitable region from an exposed end face thereof so as to approximately match the resonance frequency of the intermediate-stage resonator to the resonance frequency of the input-stage and the output-stage resonators. The dielectric filter may include at least three coaxial dielectric resonators which are bonded as arranged side by side.

Abstract: A radio frequency filter having at least two dielectric resonators in juxtaposition, each resonator including a tubular dielectric body. Formed on the dielectric body of each resonator are an inner and an outer conductors and various other conductors including a terminal conductor for connection of the filter to external circuitry. In order to assure positive isolation of the terminal conductors of both resonators from each other, the outer conductors are provided with extensions which intervene between the terminal conductors for preventing then from being capacitively coupled together.

Abstract: The bandpass filter according to the present invention includes a housing having a plurality of cavities, wherein said plurality of cavities are isolated from each other by partitions and wherein each said partition have a coupling window; input/output connectors formed at both ends of said housing so as to pass output signals from a transmitter; coupling loops connected to said input/output connectors so as to excite an applied signal power and to combine resonance modes; dielectric resonators installed in said cavities of said housing so as to resonate a signal power transmitted from said coupling loop to the desired frequency band, said dielectric resonators including: a first resonator group formed in both said cavities which are adjacent to said coupling loops; and a second resonator group formed in said cavities which are positioned between both said cavities which are adjacent to said coupling loops, wherein said resonators of said second resonator group are stepped resonators; a plurality of frequency

Abstract: A filter including first and second resonators and a coaxial cable connecting the resonators. Also, a filter including a housing and stepped impedance resonators wherein the high impedance portions of the stepped resonators are integral with the housing. Also, methods of manufacturing the filters.

Abstract: The invention relates to an arrangement for fastening an inner conductor of a resonator structure and to a method for fastening an inner conductor of a resonator structure to a fastening surface structure. The arrangement comprises a fastening surface structure, which in turn comprises an edge of an opening and the opening defined by the edge, the opening being formed through the fastening surface structure. In addition, the arrangement comprises an inner conductor of a resonator structure arranged at the opening formed through the fastening surface structure, the inner conductor comprising an inner space at least on the portion of the conductor that faces the fastening surface structure, which inner space is defined by the wall of the inner conductor which extends into the opening formed through the fastening surface structure.

Abstract: The invention relates to a method of manufacturing an inner conductor of a resonator, and an inner conductor of a resonator comprising a first end and a second end, which is free. The inner conductor is deep-drawn from a uniform, electrically conductive blank. (FIG.

Abstract: A dielectric filter in which both the resonant frequency of each resonator and the degree of coupling between resonators can be adjusted independently. The dielectric filter includes at least first and second dielectric blocks, each having a through bore extending between first and second end faces thereof and a plurality of side surfaces extending between those end faces. Substantially all of the faces of the dielectric blocks, including the bore, are covered with a conductive film to define a first dielectric resonator whose electric energy component varies in the direction of an axis of the through bore. A first coupling electrode is formed, isolated from the conductive film, on at least one and preferably bridging between two of the side surfaces of the first dielectric block for coupling an input signal applied thereto to the first dielectric resonator.

Abstract: A dielectric filter (10, 20) is provided with resonator holes 11a and 11b, and the resonator holes 11a and 11b have large-sectional area portions 12a and 12b and small-sectional area portions 13a and 13b, respectively. On the step portions 14a and 14b between the large-sectional area portions 12a and 12b and the small-sectional area portions 13a and 13b, grooves 15a and 15b or protruding portions 16a and 16b substantially surround the small-sectional area portions 13a and 13b, respectively. Inner conductors 23a and 23b formed on the inner surfaces of the resonator holes 11a and 11b are directly connected to input and output electrodes 22a and 22b formed on outer surfaces of a dielectric block 1.

Abstract: A radio-frequency shield for a diagnostic magnetic resonance apparatus has a hollow-cylindrical carrier composed of a dielectric, a first electrically conductive coating arranged at an inside of the carrier and provided with axially aligned separating slots, and A second electrically conductive coating arranged at an outside of the carrier and provided with axially aligned separating slots. The separating slots in the first and second coatings, respectively, are offset relative to one another in a circumferential direction. The first coating has slotted end regions at the ends of the carrier and at least one slofted middle region between the end regions. The separating slots arranged in the end regions are transverse slots that are arranged at axially inwardly disposed ends of the separating slots.

Abstract: A resonator filter comprising a housing formed with a conductive material. The housing defines a first cavity, a second cavity, and an intermediate wall positioned between the first and second cavities. The housing defines an opening between the first and second cavities. First and second center conductors are positioned within the first and second cavities, respectively. A coupling wire is connected between the first center conductor and the housing. The coupling wire and the center conductor have substantially equal thermal expansion coefficients.

Abstract: In a quarter-wave coaxial cavity resonator, having a cavity with a cylinder inner wall (1), and bottom (3) and top (4) walls and a symmetry axis (2) with a resonator bar (5), a high coupling degree to a feed line (12) is obtained by a T-formed antenna with two equally long arms forming the antenna proper and the stem (9) forming the lead to the feed line. The antenna proper has one end (10) electrically and mechanically connected to the bottom end (6) of the resonator rod, whereas the opposite end (11) is free, and the antenna is parallel to the resonator rod and at a small distance therefrom.

Abstract: The invention provides a dielectric filter, comprising: a dielectric block including a first surface and a second surface opposite to each other; a resonator hole extending between the first surface and second surface of the dielectric block, said resonator hole including a large-sectional area portion, a small-sectional area portion and a step portion between the large-sectional area portion and the small-sectional area portion; an inner conductor provided on the inner surface of the resonator hole; an outer conductor provided on the outer surface of the dielectric block; the inner conductor being electrically left unconnected to the outer conductor at the first surface of the dielectric block and being electrically connected to the outer conductor at the second surface of the dielectric block; and a seat portion provided on the first surface of the dielectric block such that the first surface serves as a mounting surface of the dielectric filter.

Abstract: A coaxial resonator according to the present invention has an outer conductor on an outer peripheral surface of a dielectric block having at least four side surfaces and having a through hole provided in its approximately central part and an inner conductor on an inner peripheral surface of the through hole, and one of two end faces perpendicular to the through hole is opened and the other end face is short-circuited. A pair of an input electrode and an output electrode which are not brought into electrical contact with the outer conductor and are independent of each other is provided in a position in proximity to the opened end face on the outer peripheral surface of the dielectric block, and respective portions of both the electrodes are extended to the side surfaces, which are respectively adjacent to the electrodes, of the dielectric block.

Abstract: A dielectric filter includes a first dielectric block having a through bore, substantially all of the surface area of the first dielectric block being covered with a conductive film to define a first dielectric resonator whose magnetic energy varies in the direction of an axis of the through bore. A first coupling window is formed in the conductive film on a first side surface for coupling an input signal applied thereto to the first dielectric resonator. A second coupling window is formed on a second side surface in a location wherein the magnetic energy in the first dielectric block is relatively high so that magnetic energy exits the first dielectric block via the second coupling window. A second dielectric block has a through bore and substantially all of the surface area of the second dielectric block is covered with a conductive film to define a second dielectric resonator.

Abstract: A TE0&ggr;&dgr; mode dielectric resonator (12) includes a cylindrical dielectric disk (32, 32′, 32″) having top and bottom ends (20, 22) spaced apart by a closed curve wall (24). The dielectric disk has an effective dielectric constant greater than 40. An axially aligned hole (36) is formed through the disk (32) between the top and bottom ends (20, 22). A conductive wall (34, 34″) is formed at or slightly beyond the wall (24) but does not cover the top and bottom ends (20, 22). The hole (36) has a preferred diameter between 0.21 and 0.4 times the diameter of the disk (32, 32′, 32″). The disk may be configured as a heterogeneous composite of dissimilar materials which exhibit increasing dielectric constant at increasing radial distance and increasing Q at decreasing radial distance.

Abstract: A duplexer dielectric filter comprises a dielectric block, a first filtering area including resonators having resonant holes disposed to pass through first and second surfaces of the dielectric block in a substantially parallel manner, a second filtering area including resonators having resonant holes disposed to pass through the first and second surfaces of the dielectric block in a parallel manner; first conductive pattern formed on the surroundings of the resonant holes of the first surface, thus to be connected with the conductive material covered with the interior of the resonant holes and for applying a loading capacitance to the resonators and an electromagnetic coupling between adjacent resonators, a second conductive pattern disposed on the first surface of the first filtering area along the arrangement direction of the resonant hole and for forming the electromagnetic coupling between the adjacent resonators, third conductive pattern disposed on the first surface of the first filtering area for form

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and through-holes are formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-holes as well as the outside dimensions of the dielectric block. Terminal electrodes are formed on the outer surface of the dielectric block. Coupling electrodes are formed on the inner surfaces of the through-holes. One end of each coupling electrode is connected to the corresponding terminal electrode and the other end of the coupling electrode may be connected to the conducting film formed on the outer surface of the dielectric block. Alternatively, the other end of the coupling electrode may be partially removed to adjust the amount of coupling; or may be completely removed so as to isolate the coupling electrode from the conducting film on the outer surface.

Abstract: An HF filter using resonators of a convex-concave structure is capable of easily inserting a serial or parallel capacitance inside the resonators for the sake of a characteristic improvement of frequency at a stop band desired. In the inventive HF filter, an error compensation is simple and a size smallization is available, by utilizing the resonators of the convex-concave structure.

Abstract: On the internal surface of each of the through-holes formed in a dielectric block, an internal conductor is formed, while on the external surface except the top surface, an external conductor is formed. The internal conductors, together with the external conductor and the dielectric block, form dielectric resonators with 1/4-wavelength using the top and bottom surfaces of the dielectric block as an open surface and a short surface, respectively. Each of the through-holes has a large-diameter hole portion and a small-diameter hole portion and also has a coupling adjustment hole portion for the purpose of a fine adjustment of electromagnetic coupling between adjacent the dielectric resonators.

Abstract: Antenna side through-holes pass through to the internal surfaces of neighboring resonator holes from an antenna side electrode. The antenna side through-holes (transverse holes) have their axes in a direction substantially at a right angle to the axial direction of the resonator holes and on the internal surface of the antenna side through-holes an inner conductor is formed. The transmission side filter and the antenna side electrode of a duplexer are electrically connected through an antenna side through-hole. The reception side filter and the antenna side electrode are also electrically connected through an antenna side through-hole.

Abstract: A dielectric filter in which the resonant frequency of each resonator and the degree of coupling between resonators can be adjusted independently. The dielectric filter includes first and second dielectric blocks, each having a through bore. The dielectric blocks, including the bores, are covered with a conductive film to define respective dielectric resonators whose electric energy component varies in the direction of an axis of the through bore. A first isolated coupling electrode is formed on the first dielectric block for coupling an input signal to the first dielectric resonator. A second isolated coupling electrode is formed on the first dielectric block in a location with a relatively high electric energy component so that electric energy exits the first dielectric block via the second coupling electrode.

Abstract: A resonant structure has a center conductor, a dielectric element, and an outer conductor. The center conductor is a substrate with a coating of a superconductor on its outer surface, and the outer conductor is a substrate with a coating of a superconductor on its inner surface. The dielectric element has a passageway which is sized for receiving the inner conductor so that there is substantially complete contact between the layers of superconductor coating and the dielectric. Similarly, the outer surface of the dielectric element is sized to match the inner superconductor coated surface of the outer conductor.