Abstract: The present invention relates to a radio frequency filter, comprising a block(1) of a dielectric agent and an insulation sheet (2) attached to a side surface thereof. From the top surface of the block to the undersurface, at least two holes (3,4,5) coated with a conductive agent extend. At least most of the surface of the body, with the exception of one side surface, as well as the surfaces of the holes have been coated with a conductive agent, whereby a transmission line resonator is produced for each hole. The surface of the insulation sheet (2) fixed against the uncoated side surface but not facing the block has also been coated with a conductive agent. The coupling pattern formed by the metallic electrodes is located between the opposite surfaces. The unevenness of the surfaces placed against each other and the defects in adjusting the pieces cause great divergence in the response curves of the filters.

Abstract: A dielectric filter comprises a pair of dielectric resonators 11 and 12, which have outer conductors 11c and 12c formed with cutouts 11k and 12k, respectively. Interstage coupling electrodes 11f and 12f are provided within the region of these cutouts 11k and 12k, so that the electrodes 11f and 12f do not contact with the conductors, such as outer conductors 11c, 12c and the inner conductors 11d, 12d. The dielectric resonators are connected in such a manner that these electrodes 11f and 12f are brought into contact with each other. Furthermore, input/output coupling electrodes 11g and 12g are provided within the region of the cutouts 11k and 12k. Then, by connecting the electrodes 11f and 12f, it becomes possible to provide a dielectric filter which is compact in size and capable of reducing the number of parts and, therefore, cheap in cost.

Abstract: A filter (102) with an adjustable bandwidth. The filter (102) has a predetermined passband and stopband, and an input (104), an output (106) and at least two resonator structures (116, 124), and a variable reactance element (108) for adjusting the bandwidth of the passband, coupled between the resonator structures (116, 124), whereby the frequency response is adjustable.

Abstract: A dielectric filter having a plurality of .lambda./4 coaxial dielectric resonators in stages, the resonator being filled with a dielectric material between its inner and outer conductors, comprising at least one stage in which the outer conductor of the .lambda./4 coaxial dielectric resonator is grounded via a capacitance or inductance. The dielectric filter is embodied as a low-pass filter, high-pass filter or a band-pass filter. As a result, by utilizing dielectric resonators having a desired resonant frequency, it is possible to readily achieve a dielectric filter having an attenuating pole in the neighborhood of the frequency passband and small in insertion loss.

Abstract: A balanced-type dielectric filter for use in a high frequency circuit without requiring a converter. The balanced-type dielectric filter includes a dielectric block having an approximately rectangular parallelepiped shape, at least two inner conductors being disposed in parallel-with a longitudinal direction of the dielectric block and having the length approximately equal to 1/2 of a selected wavelength. Outer conductors are disposed on at least two outside surfaces of the dielectric block and are parallel to the inner conductors. Two pairs of connecting conductors connect the two inner conductors to input and output terminals located on the side surfaced of the dielectric block, the terminals being insulated from the outer conductors.

Abstract: A dielectric ceramic composition is disclosed which consists essentially of: a main ceramic composition containing barium oxide, titanium oxide, rare earth oxide and bismuth oxide as major components, which composition is represented by xBaO.multidot.yTiO.sub.2 .multidot.z[(1-a)RE.sub.2 O.sub.3 .multidot.aBi.sub.2 O.sub.3 ] where RE represents at least one rare earth metal, 0.10.ltoreq.x.ltoreq.0.20, 0.60.ltoreq.y.ltoreq.0.75, 0.10 .ltoreq.z.ltoreq.0.25, x+y+z=1 and 0<a.ltoreq.0.3; and a glass composition composed of ZnO, B.sub.2 O.sub.3 and SiO.sub.2, which is represented by k(wt. %)ZnO.multidot.m(wt. %)B.sub.2 O.sub.3 .multidot.n(wt. %)SiO.sub.2 where 30 .ltoreq.k.ltoreq.85, 5.ltoreq.m.ltoreq.50, 2.ltoreq.n.ltoreq.40, k+m+n=100. The glass composition is contained in an amount of at least 0.1 part by weight, but not more than (18-62.5a) parts by weight (where 0<a.ltoreq.0.2) or not more than 5.5 parts by weight (where 0.2<a<0.3), per 100 parts by weight of the main ceramic composition.

Abstract: In a dielectric material block surrounded by a metal film at least one air hole is provided. Inner faces of the at least one air hole are partly applied with at least one metal film. The at least one air hole is provided for providing coupled distributed lines, which are mutually coupled by electric fields passing partly through the at least one air hole, so as to realize a dielectric band pass filter, which has a small-sized structure and attains high precision and non-alignment of resonant frequency.

Abstract: A dielectric filter in which input/output coupling electrode layers are arranged on the surfaces of the substrate sections, separated from the resonating conductors by an adjustable distance, the coupling capacitance of the device can be chosen within a wide range of selection because of the relatively large area of the surfaces. The dielectric filter comprises an interstage coupling electrode layer which is formed on a temporary surface of a dielectric substrate that has a relatively large area and becomes internal in the final product with a predetermined but adjustable distance from a pair of resonating conductors arranged in the dielectric substrate.

Abstract: A dielectric filter device including at least two dielectric resonator bodies juxtaposed to each other each provided with a through bore which has an inner conductive layer, a first dielectric substrate provided with electrodes on its surfaces for forming input and output capacities and a second dielectric substrate provided with capacitively coupled electrodes on its inner surfaces for forming a coupling capacity and an electrode which cooperates with the capacitively coupled electrodes to form stray capacities, the first and second dielectric substrates being superimposed and mounted on the front surfaces of the juxtaposed dielectric resonator bodies.

Abstract: A filter device for a transmitter-receiver antenna includes a transmission side filter having resonators and a reception side filter having resonators. Each of the transmission side resonators has a first characteristic impedance ratio other than one. On the other hand, each of the reception side resonators has a second characteristic impedance ratio being set to a value which prevents spurious resonance of the reception side filter at an integral multiple of a fundamental resonance frequency of the transmission side filter, so as to avoid the situation where spurious components increase at the above-noted integral multiple in a frequency characteristic of the transmission side filter being affected by a frequency characteristic of the reception side filter.

Abstract: In a dielectric filter according to the present invention, a depressed part is formed by removing a portion of an outer peripheral conductor on the open face side of each of a plurality of one-end face short-circuited type coaxial resonators or a portion of the outer peripheral conductor including a dielectric member. A dielectric substrate having a plurality of capacitance forming electrodes for forming antiresonance capacitances between the electrodes and inner peripheral conductors of the coaxial resonators formed thereon is mounted on the depressed part, and a reactance element for coupling the capacitance forming electrodes is provided on the dielectric substrate.

Abstract: A dielectric ceramic composition is disclosed which includes: a main ceramic composition of barium oxide and titanium oxide, or barium oxide, titanium oxide and at least one of strontium oxide, calcium oxide, zirconia and zinc oxide, which composition is represented by (1-a-b)BaO.aSrO.bCaO.x[(1-c)TiO.sub.2.cZrO.sub.2 ].yZnO, where 3.1.ltoreq.x.ltoreq.5.4, 0.ltoreq.y.ltoreq.2.9, 0.ltoreq.a+b.ltoreq.0.4, 0.ltoreq.c.ltoreq.0.2; and a secondary component at least a part of which consists of a B.sub.2 O.sub.3 material or a glass material containing B.sub.2 O.sub.3 as one of glass components, the secondary component being added to the main ceramic composition, in an amount of 0.1-7.5 parts by weight of B.sub.2 O.sub.3 per 100 parts by weight of the main ceramic composition.

Abstract: A coaxial resonator includes a ceramic body having outer surfaces including an end surface forming a connecting side. The ceramic body has a through hole extending longitudinally through the ceramic body defining an inner surface in the through hole. The end surface has an indentation formed therein surrounding the through hole. Metallizing is disposed on the inner surface and on all of the outer surfaces including the indentation except for the end surface. The metallized outer surfaces form an external conductor and the metallized inner surface forms an internal conductor. The ceramic body has notches extending inwardly from one of the outer surfaces in the vicinity of the indentation for galvanic separation of the internal conductor metallizing of the through hole and the indentation from the external conductor metallizing. The notches separate out a surface portion from the outer surface forming a connection for the internal conductor through the metallizing of the indentation.

Abstract: The present invention relates specifically to the temperature compensation of a resonator in which a rod or a conductor wound in the form of a cylindrical coil serving as an inner conductor is enclosed within a metal cover and in which the open end of the rod or the coil is spaced a given distance from the cover, thus forming a loading capacitance. A change in the resonant frequency caused by thermal expansion can be compensated for in that at the open end of the inner conductor within the housing there is provided a compensation plate (5), the center part (12) of which is spaced at a distance (a) from the top surface (4) of the housing and preferably in parallel therewith and which has at least at two opposite edge parts (8, 9) been attached to the top surface (4).

Abstract: An arrangement for coupling microwave energy with a reaction chamber, including electrically stable tuning and being, within limits, tolerant against changes in critical dimensions and power fluctuations. A coaxial line between a hollow waveguide and the reaction chamber is of such a structure that it forms, at least together with the reaction chamber, a loss resonator for the microwave frequency employed. The coaxial line can comprise an absorber or, alternatively, can be made of a poorly conductive material. There is also the possibility of downgrading the quality of the resonator by leaving an annular gap between a metal plate and an outer conductor section.

Abstract: An inexpensive and lightweight air insulated high frequency filter can be made utilizing a radio device's frame and a printed board (15) intended for electrical circuits, so that during manufacture of the printed board (15) it is machined so that several side by side finger-like projecting tongues (14.sub.1, 14.sub.2, 14.sub.3, 14.sub.4) are formed, which are entirely coated with electrically conducting material. Thereafter the printed board, on which electrical and mechanical components intended for it are mounted, is placed in the radio device's crate-like frame made of conducting material and possibly provided with partition walls (18, 19), and on which also cover parts are fastened so that the tongues will be parallel with them and located between them, whereby the tongues, the enclosing cover parts and the frame wall parts form a filter structure.

Abstract: A dielectric block filter having a self aligning, top and shield is provided. Recesses are formed in at least one side of the block, which recess is dimensioned to accept a mating tab or side of a shield that substantially encloses the top end of the filter. The recess in the block in combination with the appropriately shaped tab produces the overall height of the filter and simplifies manufacturing by eliminating the need to hold or affix the shield to otherwise smooth sides of the block.

Abstract: For removing the variation of resonant frequency of the 1/4 .lambda.g coaxial resonator, which is caused by the external connection as a result of conventional capacitive coupling, a 1/4 .lambda.g line having both ends opened is coupled to the 1/4 .lambda.g resonant line having one end shorted through distributed inductive coupling, so as to provide a basic structure of the dielectric resonator of the invention, which can be arranged in usual various types of circuits such as filters, multiplexers and the like with excellent and stable performances.

Abstract: A dielectric resonator comprising a cylindrical substrate comprised of a dielectric ceramic, a first conductive film comprised of copper, formed on the inner surface, outer surface and one end of said cylindrical substrate, and a second conductive film comprised of at least one solder and tin, formed on said first conductive film. Thus the dielectric resonator of the present invention can be free from oxidation of the copper film when heating is carried out not in an inert gas environment but in the atmosphere. Hence it becomes unnecessary to use various devices for carrying out the heating in an inert gas environment as so required in the conventional cases. This also enables reduction of the number of processing steps, resulting in an improvement in productivity. Moreover, its weatherability can be improved, so that it can promise a long lifetime.

Abstract: A dielectric filter construction having at least two resonating cavities extending longitudinally through a block of dielectric material. At least one of the resonating cavities is of a cross-sectional area which is elongated in a transverse direction, and at least one notch is formed to extend longitudinally along at least one of the surfaces of the block of dielectric material between adjacent ones of the resonating cavities. By appropriate selection of the amount of elongation of the cross-section of the resonating cavity, and the location and dimension of the notch formed along the surface of the block, the component values of the component elements comprising the filter may be selected over an increased range without altering the physical size of the filter.

Abstract: A multiple bandpass filter is disclosed having a common input intercoupling a plurality of parallel single bandpass filters which are further intercoupled to provide a composite signal at a common output. The multiple bandpass filter of the present invention is appropriate for application to ceramic filters. In a preferred embodiment, the multiple bandpass filter of the present invention has a common input, parallel distributed resonator single bandpass filters, and a common output, all integral to the same ceramic structure. The multiple bandpass filter comprises a ceramic block having a plurality of rows of holes extending from the top of the bottom of the block and a slot extending from the top to the bottom of the block, separating the rows. The block and interior of the holes and slot are substantially covered with conductive material. An area near one end of each of the holes is bare ceramic.

Abstract: A high-frequency coaxial resonator including a tubular dielectric member having a through hole and provided with inner and outer peripheral surfaces and a pair of end surfaces which axially oppose each other. An inner conductor is formed on the inner peripheral surface and an outer conductor is formed on the outer peripheral surface, the outer conductor extending onto one or both end surfaces of the tubular dielectric member so as to approach the inner conductor through a prescribed clearance, thereby forming a capacitance between the inner and outer conductors for adjusting the resonant frequency of the resonator.

Abstract: A coaxial resonator with a distributed tuning capacity. The resonator includes one outer conductor and one central conductor, both conductors having a symmetry of revolution around a predetermined central axis. The tuning capacitor is fully distributed along the axis of the resonator and includes at least two cylindrical armatures nested into each other and having the axis of the resonator as their central axis, one of the two armatures constituting one of the two conductors of the resonator. The coaxial resonator may find particular application for RMN magnetometer probes.

Abstract: A dielectric resonator block has at least three resonators and coupling device for coupling the adjacent resonators. A reactance element is added in parallel to the coupling device to provide an attenuation pole. A capacitor block of a dielectric material is provided which has through-holes to form hole electrodes and a surface electrode so that two coupling capacitances are provided. One of the two coupling capacitances serves as the reactance element. One of the hole electrodes of the capacitor block is connected with an external connector, and the other hole electrodes are connected with the resonators.

Abstract: Improved frequency characteristics can be achieved by using input/output pads on a surface mount block filter which pads are mounted on mesas formed by troughs cut through the dielectric material and metallization.

Abstract: A dielectric filter includes: a plurality of coaxial resonators and external connectors; each of the coaxial resonators includes a dielectric block having an outer peripheral surface and an inner peripheral surface parallel to a common axis and having two end faces, a conductive layer formed on the outer and inner peripheral surfaces and on one of the end faces, and a depressed part for accepting the external connection means and formed by removing a portion of the conductive layer on at least the outer peripheral surface in the vicinity of the other end face; and the external connectors includes a dielectric substrate, and an external connection electrode formed on the dielectric substrate and capacitance-coupled with the conductive layer on the inner peripheral surface.

Abstract: A dielectric filter having a generally box-like dielectric block, an outer conductor covering side surfaces of the dielectric block, a plurality of inner conductors arranged in the dielectric block in the longitudinal direction so as to extend between two opposite faces of the block, and a short-circuit conductor provided in one of the two faces of the dielectric block to connect the outer and inner conductors. At least one of the inner conductors has a rectangular cross-sectional shape, and the size of this sectional shape in the longitudinal direction of the dielectric block is increased at the face where the short-circuit conductor is provided, and is reduced at the other face.

Abstract: An ultraminiature delay line assembly for use with an electronic system. The delay line is utilized for producing and introducing a known controllable time delay to an electrical signal without the accompanying signal attenuation normally associated with traditional coaxial delay lines. The ultraminiature delay line utilizes miniature coaxial transmission cable which is smaller in diameter than the coaxial transmission cable traditionally used. An ultraminiature delay line includes a thin substrate supporting base plate. Mounted on the thin substrate supporting base plate are numerous concentrically wound miniature coaxial cable assemblies. Coupled to the middle of each miniature coaxial cable assembly is a signal amplifying device having variable programmable gain which offsets signal attenuation caused by the length of miniature coaxial cable.

Abstract: A dielectric resonator includes a resonator body having a groove formed in its upper surface adjacent to an outer periphery of a through hole formed through the body. An electrically-conductive film on the inner surface of the groove is electrically connected to an electrically-conductive film formed on the inner peripheral surface of the through hole, via an electrically-conductive film formed on a portion of the upper surface of the body lying between the groove and the through hole. The groove having the electrically-conductive film formed on its inner surface enables the length of the body to be reduced and the overall resonator to have a reduced size.

Abstract: A broadband, varactor-tuned shorted coax resonator is provided with a single point coupling port that facilitates coupling of discrete circuitry to the distributed resonator. The coupling port is defined by adding a second shorted coax line across the end of the first. The outer conductors of the two lines are interconnected. The inner conductors of the two lines are serially coupled and define a coupling gap, either along their length or at their ends, across which discrete circuitry can be connected. In a preferred form of the invention, the discrete circuitry is positioned in a region within the periphery of one of the inner conductors in order to provide an electromagnetic shield for the circuitry.

Abstract: A coaxial dielectric resonator for use at high frequency. The outer or inner peripheral surface of a tubular dielectric member is stepped so as to provide a greater suppression of spurious resonance. The dielectric member has a prism-shaped outer configuration so as to provide a high Q value, as well as improved space factor.

Abstract: A duplexer for a radio transceiver is disclosed in which two volumes of dielectric material each have at least two holes and each is covered with a conductive material except for one surface. An electrode on the one surface of each volume is coupled to one of the holes and is coupled to a substrate via a terminal passing through a mounting device. The substrate provides coupling between the terminals of the two volumes and a common antenna.

Abstract: Inductance coupling type transmission channel couplers mounted on either side of an insulator such as window glass of a vehicle including a pair of resonator, each including a cylindrical outer conductor and a helical conductor coaxially provided in the outer conductor with one end connected thereto. The resonant frequency of the tuning inductance circuit thus constructed is set at 1/3 of an objective frequency, and the ratio between the inner diameter and the outer diameter of the helical conductor is set at 1.1-2.0.

Abstract: An ingeniously designed new dielectric filter is disclosed. Such a dielectric filter comprises a first pair of groove side wall electrodes arranged on a side wall of a groove in juxtaposition with a pair of patterned input/output electrodes formed on a substrate. Since such an arrangement can provide a relatively high input/output coupled capacity of a dielectric filter, such a dielectric filter can be realized without requiring preparation of complex and finely patterned electrodes and formation of patterned capacitor electrodes on a face of a dielectric block that constitutes a principal component of the dielectric filter. The frequency of such a dielectric filter can be adjusted by simply abrasing that face of the dielectric block.

Abstract: A dielectric filter with an attenuation pole having sharp attenuation characteristics. The dielectric block employed in the present dielectric includes a dielectric block single-block formed of TiO.sub.2 or BaO, for example. The dielectric block of this type has a plurality of resonators extending from a top surface toward a bottom surface thereof, a plurality of adjusting patterns provided over the top surface thereof, an outer conductor formed by side surfaces and the bottom surface thereof, input and output electrodes, wherein the adjusting patterns, the outer conductor, input and output electrodes maybe plated, for example, by silver, and an insulated cable which may have one end connected to the outer conductor and another end connected to the output electrode is disposed over the plurality of resonators so as to be coupled thereto.

Abstract: A surface mount dielectric block filter with an integral transmission line connection to external circuitry is disclosed. In order to connect an input/output capacitor metallized on the surface of the dielectric block to a substrate upon which the dielectric block is directly mounted, a transmission line of appropriate characteristic impedance disposed on the surface of the dielectric block is connected between one plate of the metallized capacitor and an input/output terminal. Two such dielectric block filters may be coupled together to form a radio transceiver duplexer.

Abstract: An improved transmission line filter element allows a higher difference between even and odd mode impedances than previously obtainable from planar structures. The filter element comprises a U-shaped gap formed in the strip conductor of a strip line transmission line, a microstrip structure or a suspended strip line structure. The internal transmission line filters can be cascaded to produce electromagnetic energy filters with deeper notches and steeper skirts than previously obtainable from other planar structures with the same number of elements.

Abstract: This invention relates to an increase in the low longitudinal resonance frequencies of microwave transmission lines known as symmetrical lines, comprising two coplanar and parallel narrow conductive strips. According to the invention, the line further comprises a longitudinal and wide planar conductive strip which is parallel to one of the narrow strips at a sufficient distance not to substantially disturb the characteristic impedance of the initial symmetrical line and which is connected to the narrow strip by small planar end conductors thereby forming a longitudinal flat cavity. The cavity offers a first resonance frequency much greater than those of the initial symmetrical line and consequently affords a higher useful frequency bank of signals to be transmitted. The end conductors allow the line to be connected to coaxial connectors. In other embodiments, the cavity is divided into several resonant sub-cavities in order to raise the pass-band.

Abstract: A dielectric filter and a method of manufacture. The filter includes a block of ceramic material having one or more holes extending from a top surface to a bottom surface, each of which is interiorly covered with conductive material so as to form an inner conductive layer. The bottom surface and side surfaces of the block are also covered with bottom and side conductive layers electrically connected to the inner conductive layers at the bottom surface. The inner conductive layer is further connected to spaced apart top conductive layer portions provided on the top surface of the block surrounding each hole. The top layer portions are spaced from each other and have an oblique edge portion which is capacitively coupled with, and obliquely faces an upper edge portion of the side conductive layers, the oblique edge facilitating adjustment of the resonant frequency by removal of a predetermined amount of conductive material therefrom.

Abstract: Magnet (12) creates a main magnetic field along a z-axis through an image region. A localized coil (D) is disposed in the image region at least to receive magnetic resonance signals from nuclei of the subject which have been induced to resonance. The localized coil includes an inner conductor (30), an outer conductor (32), and a dielectric material (52) therebetween. The outer conductor defines a gap (50) midway between its ends. One end of the inner conductor is connected with a gate of an FET transistor (66) and the outer conductor is connected with its source. The transistor source and drain are connected by a coaxial transmission cable (38) with a DC power supply (70) which provides a DC bias across the transistor source and drain. The cable also connects the transistor with a radio frequency receiver (40) to convey preamplified magnetic resonance signals thereto.

Abstract: A multiresonator dielectric block filter is disclosed in which capacitive coupling between resonators disposed in the dielectric block is controlled by an electrode strip coupled to the conductive material covering the majority of the dielectric block surface. The electrode strip extends at least partially between two adjacent resonators to control the capacitive coupling between the resonators.

Abstract: A resonator for microwave or VHF-UHF bands has a ring dielectric plate, one surface of which is metalized to make a resonant line, and at least one of other surfaces of which is also metalized to make a grounded or earth conductor. The resonator is very small in size and has a large unloaded Q value. Several embodiments are disclosed.

Abstract: A dielectric filter of which a characteristic is stable without a gastight casing. The dielectric filter's structure is comprised of an input, an output, a dielectric having a plurality of holes extending from a top to a bottom surface thereof, each of the holes being covered with a first conductive material, a second conductive material being electrically connected to the first conductive material at the bottom surface and unconnected to the first conductive material at the top surface, and an insulating weatherproof coating provided on the top surface.

Abstract: A dielectric filter includes a single block made of dielectric material having three or more through holes, in each of which an inner conductor is deposited, to define three or more dielectric resonators coupled in a cascade manner. Coupling holes are each formed between a pair of neighboring dielectric resonators. A bypass circuit, having a reactance component, is provided for connecting between two or more coupling holes; or for connecting the through hole of the dielectric resonator and a coupling hole; or for connecting the input terminal and one or more through holes of the dielectric resonators or the coupling holes. By selecting the holes to be interconnected and the value of the reactance of the bypass circuit, it is possible to provide a filter having a frequency characteristic in a desired format, including at least one pole at a selected point in an attenuation region thereof, without any increase in the number of dielectric resonator stages of the dielectric filter.

Abstract: An adjustable electronic filter apparatus is disclosed comprising a dielectric block having one or more through-holes and having a conformal conductive coating substantially over all outside surfaces as well as each through-hole therein. Each through-hole so plated forms a resonator from a transmission line which includes an open portion, for providing capacitive reactance at a first end, and a short-circuited end as a base, for providing an associated distributed inductance at a second end thereof. A unique method of tuning the adjustable electronic filter, whether a single resonator, a plurality of resonators, or a plurality of intercoupled multi-resonator filters, is disclosed that permits bi-directional tuning for at least one resonator in each of the above exemplary embodiments. By selectively adjusting an inductive portion of the plating at the base of each resonator so tuned, a resonator is quickly and accurately adjusted to a desired frequency.

Abstract: An assembly which comprises a plurality of dielectric coaxial resonators, each comprising a generally elongated, polygonally-sectioned dielectric body having a hollow coaxially defined therein so as to extend completely through the length of the dielectric body, and also having inner and outer conductors formed respectively on inner and outer peripheral surfaces thereof, and a mount for the support thereon of the coaxial resonators. The mount has side abutments set up from the mount for engagement with respective sides of the coaxial resonators whereby the position of each coaxial resonator relative to the mount can be restricted by the corresponding side abutments.

Abstract: A stripline filter resonator structure is provided which exhibits high Q and results in a filter with low insertion loss. The dielectric consists of two sections of dielectric material. A groove shaped as half an ellipse is formed in each of the sections. The surface of the grooves are covered with electrically conductive material. The two grooves are aligned and filled with adhesive material to hold the two dielectric sections together. An elliptically shaped resonator is thus formed in the center of the dielectric sandwich. Ground plane layers are respectively situated on the outer layers of the dielectric sandwich thus forming a stripline resonator structure. This unique resonator structure results in a more uniform current density around the periphery and thus undesired current bunching is correspondingly decreased.

Abstract: A microwave filter comprising a rectangular ceramics block (30) having a plurality of elongated parallel holes (31-36) extending from the top surface to the bottom surface thereof. The holes are plated with conductive layers (37, 38), and flat conductive areas (39-44) coupled with the layers (37, 38) spatially disposed on the top surface of the dielectric block (30) surround opening ends of the holes (31-36). An input terminal and an output terminal are provided adjacent to the conductive areas (39, 44) at both the extreme sides of the dielectric block (30).

Abstract: A ceramic TEM resonator bandstop filter is disclosed wherein the direct inter-resonator coupling is retarded by a plurality of shorting holes which are positioned between the resonators and extend from the top surface to the bottom surface of said ceramic filters. Furthermore, there is disclosed a transverse electrical connector which electrically connects the shorting holes with the opposite sides of the typical metalization found on ceramic TEM resonator filters. Furthermore, there is disclosed a method of making a capacitor for each resonator with the bottom capacitor pad being formed directly upon the top surface of the ceramic of the filter while the top capacitor pad is formed upon the top surface of a circuit board which is placed above the top surface of the filter.

Abstract: An embodiment of a unique ceramic bandstop filter is comprised of a dielectric plate having an input electrode disposed centrally on the top surface thereof and a dielectric block fixedly attached to the bottom surface of the plate and having a hole opposite the input electrode. The dielectric material is preferably a ceramic comprised of BaO, TiO.sub.2 and ZrO.sub.2 : The dielectric block is entirely plated with copper or silver except for a portion of the top surface surrounding the hole and is essentially a short-circuited coaxial transmission line. In another embodiment of the unique ceramic bandstop filter, a dielectric block has a hole extending between top and bottom surfaces thereof and an input electrode plated on the top surface near the hole. The dielectric block is entirely plated with copper or silver except for a portion of the top surface surrounding the input electrode and hole.