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 dielectric filter including a dielectric block having two through bores, an outer conductor covering an outer peripheral surface of the block and one end face of the block, an inner conductor covering an inner periphery of the block, and a pair of input and output electrodes formed on the surface of the block, the other end face of the block being in the form of an open end face having no conductor layer. The pair of input and output electrodes are opposed to each other on one plane, and a dielectric block exposing portion having no conductor layer thereon is formed between the two electrodes. The block is provided in the other end face thereof with one groove dividing the open end face, and an inner surface defining the groove is provided with a conductor layer joined to the outer conductor.

Abstract: A hybrid filter assembly is provided having a first ceramic triple-mode mono-block resonator, a second ceramic triple-mode mono-block resonator and at least one metallic resonator coupled to at least one of the first and second mono-block resonators. Each triple-mode mono-block resonator supports three resonant modes and each metallic resonator supports an additional mode, thereby providing a hybrid filter assembly of reduced size having more than six poles.

Abstract: A dielectric electronic component such as a dielectric duplexer includes a dielectric ceramic block, a plurality of resonators arranged in a row in the dielectric ceramic block, and at least one terminal pad formed on a side surface of the dielectric ceramic block and coupled to a selected one of the resonators. An attenuation adjustment electrode is provided on an end face of the dielectric ceramic block in the vicinity of the selected resonator. The attenuation adjustment electrode has a base conductor portion extending from the terminal pad and having an edge that faces the end of the selected resonator, and first and second adjustment conductor portions projecting from the base conductor portion and directly oppositely along a general path or direction defined by the arrangement of the resonators. The first and second adjustment conductor portions are selectively ground away in order to adjust the frequency of the attenuation peak of the frequency characteristics of the component.

Abstract: A dielectric filter provided with a dielectric block including at least four resonant through holes that are adjacent to each other. A multipath slot is arranged near three adjacent through holes of the at least four resonant through holes. The multipath slot has an inner conductor formed on an inner surface thereof in order to generate a first capacitance between a first area near the open end of each of the three adjacent through holes and the inner conductor of the multipath slot. A step is formed so that a second capacitance is generated between a second area near the open end of each of two through holes of the at least four resonant through holes and an outer conductor located within the step. An attenuation peak is generated at the lower-frequency side of the passband with the multipath slot and the three adjacent through holes, and an attenuation peak is generated at the higher-frequency side of the passband with the two through holes and the outer conductor within the step.

Abstract: An improved radio frequency diplexer has resonators which are associated either with the transmission path or with the reception path, and at least two additional resonators are also provided. The at least two additionally provided resonators form an interconnection resonator pair which are strongly coupled to one another. Both the transmission path and the reception path are coupled to the second additional resonator, or both the transmission path and the reception path are coupled to the first additional resonator which is provided for inputting to/outputting from the common signal path.

Abstract: A dielectric filter includes a dielectric block having a plurality of through holes; an outer conductor provided on an outer surface of the dielectric block; and inner conductors provided on inner surfaces of the plurality of through holes. The dielectric filter also includes a first dielectric provided between the respective inner conductors and the outer conductor; and at least one second dielectric provided between the inner conductors of two adjacent through holes. The temperature coefficient of the resonant frequency of the first dielectric is different from that of the second dielectric. If inductive coupling between the adjacent resonators generates an attenuation pole at a frequency higher than a pass band, the temperature coefficient of the resonant frequency of the first dielectrics is set to a predetermined positive value, and the temperature coefficient of the resonant frequency of the second dielectric is set to a predetermined negative value.

Abstract: A method of manufacturing a dielectric filter comprises the steps of: forming a dielectric block; depositing a conductor on the side surfaces and the second surface of the dielectric block, and forming a plurality of resonators, forming input and output terminals on the side surface of the dielectric block, and forming conductive patterns on at least a part of the area of the first surface; and depositing a thermosetting resin on the first surface provided with the conductive patterns, and curing the thermosetting resin. The dielectric filter comprising the protection layer on an open surface prevents defects such as a short circuit generated in a trimming step. The interval between the patterns is reduced to less than 0.04 mm, advantageously facilitating miniaturization of the dielectric filter.

Abstract: A dielectric filter includes a conductive cover formed by bending a metal plate and forming at least one inwardly projecting portion at a predetermined position along the bent portion. The inner surface of the at least one inwardly projecting portion abuts on an open circuit surface or edge of a dielectric block. Thus, the distance between the open circuit surface of the filter and the conductive cover is reliably maintained and unnecessary coupling between adjacent resonators is prevented.

Abstract: In a parallel multistage band-pass filter, a transmission line having an electrical length substantially equal to half (?/2) of the wavelength of the transmission signal is incorporated between the port on the input terminal side of the odd number (2n?1)th resonator numbered from the input terminal side and the port on the input terminal side of the even number (2n)th resonator numbered from the input terminal side; and a transmission line having an electrical length substantially equal to ?/2 is incorporated between the port on the output terminal side of the even number (2n)th resonator numbered from the input terminal side and the port on the output terminal side of the odd number (2n+1)th resonator numbered from the input terminal side. Moreover, a transmission line for adjustment of a transmission phase between the input terminal and the output terminal is incorporated between the first resonator numbered from the output terminal side and the output terminal.

Abstract: An excitation hole is provided inside a dielectric block and, on the outer surface of the dielectric block, an input-output terminal electrically connected to an inner conductor inside the excitation hole is formed at one end portion of the excitation hole. A grounding-electrode-free portion is provided on the surface opposite to an input-output electrode of a mounting substrate with which the input-output terminal makes contact. Thus, the electric field strengths in upward and downward directions toward an outer conductor of the dielectric block from the excitation hole are balanced to suppress spurious TE-mode signals, etc.

Abstract: There is disclosed a half-wavelength (?/2) resonator which is constituted of a micro strip line or a strip line and in which line pattern portions are disposed symmetrically with respect to a reference line, connected to each other to form an L shape, and formed in an open loop shape so as to have open ends. For one pair of line pattern portions having the open ends, base portions connected to adjacent line pattern portions are disposed in the vicinity of the reference line, and the open ends are extended in opposite directions so that the ends are disposed apart from the reference line.

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 invention provides a method and apparatus for a adaptively predistorted filter which has a transfer function that satisfies performance criteria specified for at (east one property of the filter. The transfer function is obtained by adaptively predistorting the transfer function poles to meet the performance criteria such that at least one of the poles is shifted by a unique amount.

Abstract: A signal separator and bandpass filter that use plates with posts. The signal separator uses two bandpass filters to separate two signals of different carrier frequencies from one another. The bandpass filters each have a transmission line with the metallic plates disposed along its length. The number of plates and the distances between adjacent plates determine the bandwidth and the rejection capability of the filter.

Abstract: The invention concerns a method for optimizing elements of a narrow or intermediate band bandpass filter whereof the LC prototype has been determined. The invention is characterized in that it comprises steps which consist in: (i) breaking down several parallel or series capacitors of resonators with X elements, (ii) inserting pairs of transformers between the first and second separated element and the rest of the resonator, (iii) displacing the residual transformers to modify the impedance levels of the resonators, and (iv) absorbing the residual transformers by transformation. The invention also concerns the resulting filters.

Abstract: The present invention provides a dielectric duplexer 10 comprising a receiving filter 1 and a transmitting filter 2 which are connected in parallel with an antenna connecting terminal portion 17, and both the filters 1, 2 are integrally assembled into a common dielectric block 11. A trap circuit 8 for suppressing a predetermined frequency band different from the receiving band of the receiving filter 1 and from the transmission band of the transmitting filter 2 is integrally assembled into the dielectric block 11 along with the filters 1, 2, and is connected to the antenna connecting terminal portion 17.

Abstract: A plurality of cylindrical inner conductor portions having different diameters are connected with each other to form an inner conductor. The inner conductor portions include high-impedance portions and low-impedance portions. The inner conductor is formed within an outer conductor with a nonuniform inner diameter. The inner conductor is formed so that the axial length of some of the inner conductor portions forming the high-impedance portions is smaller than the axial length of the other inner conductor portions forming the high-impedance portions, and the diameter of the inner conductor portions forming the high-impedance portions is greater than a predetermined minimum diameter.

Abstract: A system and method for a novel microwave coaxial resonator oscillator using a ?ths wavelength resonator is described. The novel system and method provides a coaxial resonator for operation at high frequencies comprising a conductive resonator and a coaxial conductive outer shell electrically connected by an conductive end member, wherein the conductive resonator and outer shell are of a length approximately equal to (1/8+n/2) of the wavelength of the desired frequency, where n is a positive integer. The novel system and method provides a low noise oscillator for operation at high frequencies and reduces oscillator phase noise in high Q implementations. The novel system and method also provides for reducing the aspect ratio of a 1/8 wavelength coaxial resonator by increasing in a stepwise manner the length of the coaxial resonator by n/2 wavelengths of the resonator frequency, where n is a positive integer.

Abstract: Resonator holes are provided so as to extend between opposing surfaces of a dielectric filter. At least one of the resonator holes have large-diameter hole portions, and small-diameter hole portions communicating with the large-diameter hole portions, respectively. The small-diameter hole portions are provided in one of the opposing surfaces. The axes of the small-diameter hole portions and the axes of the large-diameter hole portions are displaced, respectively, such that the displacement distance P therebetween is within a range which satisfies the relationship R?r<P<R+r, where R is the radii of the large-diameter hole portions and r is the radii of the small-diameter hole portions. The large-diameter hole portions and the small-diameter hole portions overlap each other in the axial directions of the resonator holes.

Abstract: A dielectric filter includes a plurality of resonators provided in a dielectric block in parallel to each other. Each resonator is formed through providing an inner conductor on a wall surface of a through-hole extending between first and second end surfaces of the block. An outer conductor is provided on end and side surfaces of the block except for the first end surface. The inner conductor and the outer conductor are connected together so that the second end surface serves as a short circuit end surface, and the first end surface serves as an open end surface. A pair of input-output terminals are provided on a side surface of the block so that the input-output terminals are located adjacent to the open end surface at respective positions corresponding to open ends of two of the resonators. Insulating sections on the side surface isolate corresponding input-output terminals from the outer conductor formed on the side surface of the block.

Abstract: A dielectric resonator includes a high-frequency dielectric ceramic containing a first ceramic having an adhesive strength of 70 newtons or more per 2 millimeter square to metallic coatings and a second ceramic having an adhesive strength of less than 70 newtons per 2 millimeter square to metallic coatings. The dielectric ceramic has composition in which the condition 10≦{A/(A+B)}×100<100 is satisfied, where A represents the volume of the first ceramic and B represents the volume of the second ceramic.

Abstract: A reduced size ceramic block filter has trap holes whose center is askew from the line running through the center of the transmission poles such that the height-wise distance between its center and the center line of the transmission poles is greater than (dt+d1)/2, but not greater than 3/8 of the height of the filter. The trap hole is also width-wise spaced from the next nearest transmission hole by an amount which approximates the distance between transmission holes. Due to this layout the diameter of the trap holes are reduced in order to maintain performance which is equivalent to a conventional filter whose trap holes are timely aligned with its transmission poles. The combination of reduced trap hole diameter and reduced width-wise spacing between traps and transmission holes, results in a reduced size ceramic filter.

Abstract: A dielectric filter provided with a dielectric block including at least four resonant through holes that are adjacent to each other. A multipath slot is arranged near three adjacent through holes of the at least four resonant through holes. The multipath slot has an inner conductor formed on an inner surface thereof in order to generate a first capacitance between a first area near the open end of each of the three adjacent through holes and the inner conductor of the multipath slot. A step is formed so that a second capacitance is generated between a second area near the open end of each of two through holes of the at least four resonant through holes and an outer conductor located within the step. An attenuation peak is generated at the lower-frequency side of the passband with the multipath slot and the three adjacent through holes, and an attenuation peak is generated at the higher-frequency side of the passband with the two through holes and the outer conductor within the step.

Abstract: A dielectric filter and a dielectric duplexer have structures for coupling between resonators, in which a range for determining the coupling strength between the resonators can be broadened and the polarity of the coupling can be changed. In addition, a communication apparatus incorporating the dielectric filter or the dielectric duplexer can be provided. Inside a dielectric member, resonance line holes having resonance lines formed on the inner surfaces thereof are disposed. Both ends of each of the resonance line holes are open-circuited. The inner diameter of each of the resonance line holes is changed at some point in the longitudinal direction of each resonance line to form a stepped part.

Abstract: A dielectric filter has a dielectric block 1 having a first end face 1a, a second end face disposed in opposite side to the first end face and lateral faces each being disposed between edges of the first and second end faces; a plurality of resonators each having a through hole 6 which lies between the first and second end faces of the dielectric block 1 and is coated with an inner conductor 3, and an outer conductor 5 coated on the second end face and the lateral faces of the dielectric block 1; and input/output electrode 4 which is insulated from the outer conductor 5 and capacitively coupled to one of the resonators at input or output stage on the first end face 1a, and extends to a mounting surface which is one of the lateral faces of the dielectric block. The input/output electrode 4 includes a conductor pattern 4b formed on the first end face 1a and having an inductance component which self-resonates at a predetermined frequency.

Abstract: A composite filter has a dielectric notch filter; and a first surface acoustic wave filter. An attenuation band of the dielectric notch filter and an attenuation band of the first surface acoustic wave filter have at least a common band portion; and the dielectric notch filter and the surface acoustic wave filter are connected in cascade.

Abstract: The invention is related to the field of tunable multiplexers. It consists of a tunable microwave multiplexer comprising a plurality of channel filters coupled to a combining/dividing mechanism. The plurality of channel filters can be either dielectric loaded resonators or combline resonators, while the combining/dividing mechanism can be a common resonator. In one embodiment, the common resonator is a multiple half-wavelength coaxial resonator.

Abstract: A dielectric filter including: a &lgr;/2 resonator for generating resonance of ½-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a pair &lgr;/4 resonators respectively for generating resonance of ¼-wavelength at a frequency substantially equal to the predetermined frequency, each having one end open-circuited and the other end short-circuited; wherein the pair of &lgr;/4 resonators are disposed in proximity to each of both ends from the vicinity of the center of the &lgr;/2 resonator; a terminal coupling to the &lgr;/2 resonator is provided as an unbalanced terminal; and terminals coupling to the pair of &lgr;/4 resonators is used as a balanced terminal. In the above filter, the balanced-type input/output of signals can be performed without using a balun.

Abstract: The extent of input/output coupling of a dielectric electronic component such as a dielectric filter or a dielectric duplexer can be adjusted by a novel method. The dielectric filter 1 comprises excitation holes whose short-circuiting ends are provided with respective coupling-adjusting countersinks.

Abstract: A dielectric duplexer device is provided with an output terminal pad formed on a side surface of a dielectric block in the vicinity of an open end associated with a plurality of resonators of a reception section in such a manner as to face the resonators. An extension electrode extends from the output terminal pad onto an end face of the dielectric block where the open end is present, to thereby be capacitively coupled with the resonators. The coupling capacitance can be readily corrected by adjusting the position of the end of the extension electrode. In one specific form, when the dielectric duplexer is mounted, the extension electrode is exposed and is also joined to a predetermined conductive path by means of solder. Accordingly, the output terminal pad is soldered at the bottom and side surfaces thereof to thereby be fillet-soldered, thereby providing visibility of electrical and mechanical connections thereof to the predetermined conductive path and thus enhancing the reliability of the mounted state.

Abstract: A small in-band-flat-group-delay type dielectric filter having low-loss characteristics with a small amplitude deviation and uniform-group-delay frequency characteristics is obtained, which enables broad-band characteristics to be obtained easily. The in-band-flat-group-delay type dielectric filter includes a plurality of dielectric coaxial resonators, a coupling circuit comprising a combination of reactive elements, with which the dielectric coaxial resonators are coupled to one another, and input/output terminals connected to ends of the coupling circuit. The dielectric coaxial resonators coupled to the input/output terminals are allowed to have a different characteristic impedance from that of the inter-stage dielectric coaxial resonators.

Abstract: The present invention is a filter and a method of making a filter to remove unwanted frequency harmonics associated with current filters. The filter is made up of resonators, such that the filter resonates a design frequency. Whereby, at least two resonators are coupled together between an input and an output and at least one of the resonators is of a different design from other resonators, such that the resonator of a different design resonates the same design frequency as the other resonators and resonates different higher order harmonic frequencies than the other resonators. The present invention also provides methods of improving skirt response for a filter, as well as other response properties of the filter. One way to improve the filter's properties is where at least one of the resonators in a filter is reversed in orientation as compared to the other resonators.

Abstract: A duplexing communication signal filter has a prismoid dielectric core having three sets of paired opposed sides. The dielectric core defines at least one through-hole passageway between one set of the pair opposed side and a void in one of the paired sides other than the apertured opposed sides. Present on the core of dielectric material is a surface-layer pattern of metallized and unmetallized areas including a relatively expansive metallized region to provide a reference potential, an unmetallized region surrounding one or more of the apertures, a transmitter pad, a receiver pad spaced apart from the transmitter pad, an antenna pad positioned between the transmitter pad and the receiver pad, and a second unmetallized region on the void to provide an unmetallized void.

Abstract: A dielectric filter capable of easily obtaining desired filter characteristics by strongly coupling mutually adjacent resonators with high accuracy even when reducing the height of the entire filter. In this filter, inside a dielectric block, there are disposed inner-conductor-formed holes in which inner conductors are formed on the inner surfaces of the holes. Coupling electrodes are arranged on an outer surface of the dielectric block and are electrically connected to the inner conductors. Additionally, the coupling electrodes are extended, for example, from the edge of an opening surface of the dielectric block which contains the open ends of the inner-conductor-formed holes, onto a side surface which is disposed parallel to a direction in which the inner-conductor-formed holes are aligned. The invention also provides a duplexer and a communication apparatus using the dielectric filter.

Abstract: A dielectric filter includes a dielectric block having inner-conductor-formed holes extending from a first face of the dielectric block to a second face opposed to the first face. Inner conductors are formed inside the inner-conductor-formed holes such that both ends of the inner-conductor-formed holes are open-circuited. On the exterior surface of the dielectric block, balanced input/output terminals are capacitively coupled to the open ends of the inner-conductor-formed holes. A metal cover is provided so as to cover one of the first or second face of the dielectric block. The metal cover functions as a short-circuit conductor in a spurious mode such as a TE mode other than a TEM mode, and hence the influence of the spurious mode is avoided.

Abstract: A duplexer dielectric filter is disclosed. This filter has a dielectric block, with reception and transmission areas formed on the dielectric block and respectively having a resonator formed by a resonating hole. This resonating hole is at least partially coated with a conductive material on its internal surface. Reception and transmission terminals are formed on the upper and side surfaces of the dielectric block at positions corresponding to the reception and transmission areas and are insulated from the conductive material of the side surface of the dielectric block. An antenna terminal is arranged between the reception and transmission areas. An open area, free from a conductive material, is formed on at least a part of the side surface of the dielectric block at a position corresponding to the reception area.

Abstract: In a dielectric block, an array of three excitation holes, in each of which one opening is a short-circuited end and the other opening is an open-circuited end, are disposed so as to be interdigitally coupled and balanced input-output terminals are provided at the opening of the excitation holes at both ends of the array. A resonator hole is provided so as to be coupled to one excitation hole of the excitation holes at either end of the array. Thus, a compact dielectric filter with balanced input-output terminals is constructed.

Abstract: A small in-band-flat-group-delay type dielectric filter having low-loss characteristics with a small amplitude deviation and uniform-group-delay frequency characteristics is obtained, which enables broad-band characteristics to be obtained easily. The in-band-flat-group-delay type dielectric filter includes a plurality of dielectric coaxial resonators, a coupling circuit comprising a combination of reactive elements, with which the dielectric coaxial resonators are coupled to one another, and input/output terminals connected to ends of the coupling circuit. The dielectric coaxial resonators coupled to the input/output terminals are allowed to have a different characteristic impedance from that of the inter-stage dielectric coaxial resonators.

Abstract: Resonator holes are provided so as to extend between opposing surfaces of a dielectric filter. At least one of the resonator holes have large-diameter hole portions, and small-diameter hole portions communicating with the large-diameter hole portions, respectively. The small-diameter hole portions are provided in one of the opposing surfaces. The axes of the small-diameter hole portions and the axes of the large-diameter hole portions are displaced, respectively, such that the displacement distance P therebetween is within a range which satisfies the relationship R−r<P<R+r, where R is the radii of the large-diameter hole portions and r is the radii of the small-diameter hole portions. The large-diameter hole portions and the small-diameter hole portions overlap each other in the axial directions of the resonator holes.

Abstract: Resonator holes are provided so as to extend between opposing surfaces of a dielectric filter. At least one of the resonator holes have large-diameter hole portions, and small-diameter hole portions communicating with the large-diameter hole portions, respectively. The small-diameter hole portions are provided in one of the opposing surfaces. The axes of the small-diameter hole portions and the axes of the large-diameter hole portions are displaced, respectively, such that the displacement distance P therebetween is within a range which satisfies the relationship R−r<P<R+r, where R is the radii of the large-diameter hole portions and r is the radii of the small-diameter hole portions. The large-diameter hole portions and the small-diameter hole portions overlap each other in the axial directions of the resonator holes.

Abstract: A dielectric filter comprising a dielectric block having first and second opposed surfaces with a width direction and a length direction greater than the width direction. At least three conductive through holes are arrayed in the dielectric block in the length direction. In one embodiment, a sectional shape of at least one conductive through hole located between two other conductive through holes of the at least three conductive through holes is elongated in the width direction. In another embodiment, a sectional shape of two conductive through holes on either side of a third conductive through hole of the at least three conductive through holes is elongated in the width direction. With these arrangements, the jumping coupling capacitance is controlled.

Abstract: A dielectric filter includes a conductive cover formed by bending a metal plate and forming at least one inwardly projecting portion at a predetermined position along the bent portion. The inner surface of the at least one inwardly projecting portion abuts on an open circuit surface or edge of a dielectric block. Thus, the distance between the open circuit surface of the filter and the conductive cover is reliably maintained and unnecessary coupling between adjacent resonators is prevented.

Abstract: A dielectric duplexer includes a substantially-rectangular-parallelepiped-shaped dielectric block. The interior of the dielectric block includes inner-conductor-formed holes containing inner conductors. An outer conductor is formed on the substantial entirety of an exterior surface of the dielectric block. Input/output electrodes and antenna input/output electrodes are formed at predetermined positions. Thus, the dielectric block is provided with a band eliminate filter and a band pass filter. A C-L-C &pgr;/2 phase circuit in which C, L, and C are arranged in the shape of the letter &pgr; is provided between an antenna and the antenna input/output electrode of the band eliminate filter, and the antenna is connected to the antenna input/output electrode of the band pass filter.

Abstract: A dielectric block includes a plurality of plated through holes each having an inner conductor formed thereon to form respective plated through holes. At least one of the plated through holes branches into two legs at the short circuit side thereof so that the two legs are close to the short circuit side of the plated through holes adjacent thereto. This allows the resonators formed of the plated through holes to be strongly inductively coupled with each other.

Abstract: Disclosed are a dielectric filter and a duplexer dielectric filter, for preventing a short circuit between patterns generated in a tuning step performed on an open surface, and method for manufacturing the filters. The method for manufacturing a dielectric filter comprises the steps of: forming a dielectric block; depositing a conductor on the side surfaces and the second surface of the dielectric block, and forming a plurality of resonators, forming input and output terminals on the side surface of the dielectric block, and forming conductive patterns on at least a part of the area of the first surface; and depositing a thermosetting resin on the first surface provided with the conductive patterns, and curing the thermosetting resin. The dielectric filter comprising the protection layer on an open surface prevents defects such as a short circuit generated in a trimming step. Therefore, since the interval between the patterns is reduced to less than 0.

Abstract: A dielectric device includes a dielectric substrate that includes at least one resonator unit. An external conductor film covers most of the outer surface of the dielectric substrate, except one end surface. The at least one resonator unit includes a first hole and a second hole. The first hole is provided in the dielectric substrate, extending from the end surface to an opposite surface, being open at the end surface and the opposite surface, and having a first internal conductor inside thereof. The second hole is provided in the dielectric substrate at a predetermined distance from the first hole, extends from the end surface toward the opposite surface, being open at the end surface, closed at the opposite surface, and having a second internal conductor inside thereof. The second internal conductor is connected to the first internal conductor at the end surface.

Abstract: A dielectric block has opposing open and closed end faces extending between opposing top and bottom surfaces thereof. An outer conductor is formed on an outer surface of the dielectric block including the top and bottom surfaces and the closed end face thereof. A plurality of plated through holes extend from the front to the rear face of the dielectric block, the plated through holes having respective internal conductors formed thereon. The internal conductors are conductively coupled to the outer conductor at the closed end face of the dielectric block. An excitation hole extends from the open to the closed end face of the dielectric block and has an inside electrode formed thereon. The inside electrode is conductively coupled to the outer conductor at the open end face thereof. An input-output electrode extends over the open end face of the dielectric block and the mounting surface and is conductively coupled to the inside electrode.

Abstract: A microwave filter having a temperature compensating element includes a housing wall structure, a filter lid, a resonator rod, a tuning screw and the temperature compensating element. The housing wall structure defines a cavity. The filter lid closes the cavity. The resonator rod is within the cavity. The tuning screw is adjustably mounted through the filter lid and has a portion that protrudes into the cavity and is coaxial with the resonator rod. The temperature compensating element is joined to the filter lid or the housing and forms a bimetallic composite with the filter lid or housing that deforms with a change in ambient temperature.

Abstract: A shield that can prevent the thickness of a dielectric filter from increasing without increasing the manufacturing cost of the dielectric filter is disclosed. The shield of the present invention is to be attached to a dielectric filter and has a first plate, a second plate elongated from the first end of the first plate in a predetermined direction, a third plate elongated from the second end of the first plate opposite to the first end in the predetermined direction, and a projecting part projecting from the first plate at a portion between the first and second ends of the first plate. Since the shield can be fixed to the dielectric filter by pinching the both side of the dielectric block and the projecting part can be in contact with the metallization of the dielectric filter, the total thickness of the dielectric filter does not increase even the shield is attached.