Abstract: A nonreciprocal circuit device (2-port isolator) includes a ferrite-magnet assembly including a ferrite, a first center electrode, and a second center electrode. The ferrite is sandwiched between a pair of permanent magnets and receives a direct-current magnetic field applied thereto. The first and second center electrodes are arranged on the ferrite. The ferrite includes a center layer and an outer layer ensuring an insulation state of the first and second center electrodes. The saturation magnetization of the outer layer is larger than the saturation magnetization of the center layer.

Abstract: A nonreciprocal circuit device (2-port isolator) includes a ferrite-magnet assembly including a ferrite, a first center electrode, and a second center electrode. The ferrite is sandwiched between a pair of permanent magnets and receives a direct-current magnetic field applied thereto. The first and second center electrodes are arranged on the ferrite. The ferrite includes a center layer and an outer layer ensuring an insulation state of the first and second center electrodes. The saturation magnetization of the outer layer is smaller than that of the center layer.

Abstract: A ferrite magnet device, a nonreciprocal circuit device, and a composite electronic component are provided. The ferrite magnet device includes a ferrite element having a plurality of central electrodes arranged to intersect one another in an electrically insulated state, and a pair of permanent magnets fixed to both main surfaces of the ferrite element so as to apply a direct current magnetic field to the ferrite element. The central electrodes are made of metal foils provided on both main surfaces of the ferrite element, with adhesive layers therebetween. Electrodes provided on the upper and lower surfaces of the ferrite element are formed by plating in through holes.

Abstract: A multiple-mode dielectric resonator in which a through hole is formed in a substantially cubic dielectric core so as to pass through opposing surfaces thereof. A conductive support bar is inserted into the through hole. Both ends of the support bar are secured to a cavity, and opposing inside walls defining the cavity are electrically connected to each other (are short-circuited) by the support bar. Therefore, the dielectric core is disposed in the cavity without using a support base, so that the resonance frequencies of TM01 delta modes, which are spurious modes, are considerably separated from frequencies of TE01 delta modes that are used.

Abstract: A non-reciprocal circuit element capable of improving an isolation characteristic without increasing an insertion loss includes a permanent magnet, a ferrite arranged to receive a direct-current magnetic field from the permanent magnet, and first and second center electrodes disposed on the ferrite. One end of the first center electrode is connected to an input port, whereas the other end is connected to an output port. One end of the second center electrode is connected to the output port, whereas the other end is connected to a ground port. A matching capacitor and a resistor are connected between the input port and the output port. An inductor and a capacitor constituting an LC resonant circuit are connected in series with the resistor.

Abstract: A nonreciprocal circuit device includes permanent magnets, a ferrite to which a direct current magnetic field is applied by the permanent magnets, first and second central electrodes arranged on the ferrite, and a circuit substrate. A ferrite-magnet assembly mounted on the circuit substrate is covered with a resin layer. The resin layer includes an innermost layer made of a non-magnetic resin material and a magnetic resin layer having a magnetic filler mixed therein.

Abstract: A multiple-mode dielectric resonator in which a through hole is formed in a substantially cubic dielectric core so as to pass through opposing surfaces thereof. A conductive support bar is inserted into the through hole. Both ends of the support bar are secured to a cavity, and opposing inside walls defining the cavity are electrically connected to each other (are short-circuited) by the support bar. Therefore, the dielectric core is disposed in the cavity without using a support base, so that the resonance frequencies of TM01 delta modes, which are spurious modes, are considerably separated from frequencies of TE01 delta modes that are used.

Abstract: A non-reciprocal circuit element capable of improving an isolation characteristic without increasing an insertion loss includes a permanent magnet, a ferrite arranged to receive a direct-current magnetic field from the permanent magnet, and first and second center electrodes disposed on the ferrite. One end of the first center electrode is connected to an input port, whereas the other end is connected to an output port. One end of the second center electrode is connected to the output port, whereas the other end is connected to a ground port. A matching capacitor and a resistor are connected between the input port and the output port. An inductor and a capacitor constituting an LC resonant circuit are connected in series with the resistor.

Abstract: Dielectrics fixed on holders respectively provided at semi-coaxial cavity resonator stages are movably inserted through an outer conductor. The holders projecting out of the outer conductor are coupled to a coupling member, and the coupling member is directed to slide or turn, so that distances between the dielectrics and the inner conductors of the resonators are varied, and accordingly frequencies of the resonators are varied at the same time. Accordingly, there is provided a tunable filter that avoids an increase in insertion loss, is high-power resistant, does not cause intermodulation, and allows a center frequency of the filter to be varied steplessly and quickly.

Abstract: A nonreciprocal circuit device includes permanent magnets, a ferrite to which a direct current magnetic field is applied by the permanent magnets, first and second central electrodes arranged on the ferrite, and a circuit substrate. A ferrite-magnet assembly mounted on the circuit substrate is covered with a resin layer. The resin layer includes an innermost layer made of a non-magnetic resin material and a magnetic resin layer having a magnetic filler mixed therein.

Abstract: Two TE modes whose electric-field rotating planes have a perpendicular relationship are coupled independently of the coupling between two TM modes whose electric-field directions have the same respective perpendicular relationships. In a multimode dielectric resonator device producing four modes: TM01?_x mode, TM01?_y mode, TE01?_x mode, and TE01?_y mode, protrusions (Pe1), (Pe2) are disposed on an upper-layer (La) and a lower-layer of a dielectric core (1) to cause a difference in effective dielectric constants of individual parts through which even-mode and odd-mode electric flux of the TE coupling modes passes. A protrusion (Pc) is formed on a middle-layer Lb of the dielectric core (1) such that the effective dielectric constants of the parts through which even-mode and odd-mode electric flux of the TM coupling modes pass become substantially equal. Thereby, the TE01?_x mode and TE01?_y mode are coupled while restraining the coupling of the TM01?_x mode and the TM01?_y mode.

Abstract: A multiple-mode dielectric resonator in which a through hole is formed in a substantially cubic dielectric core so as to pass through opposing surfaces thereof. A conductive support bar is inserted into the through hole. Both ends of the support bar are secured to a cavity, and opposing inside walls defining the cavity are electrically connected to each other (are short-circuited) by the support bar. Therefore, the dielectric core is disposed in the cavity without using a support base, so that the resonance frequencies of TM01 delta modes, which are spurious modes, are considerably separated from frequencies of TE01 delta modes that are used.

Abstract: Dielectrics fixed on holders respectively provided at semi-coaxial cavity resonator stages are movably inserted through an outer conductor. The holders projecting out of the outer conductor are coupled to a coupling member, and the coupling member is directed to slide or turn, so that distances between the dielectrics and the inner conductors of the resonators are varied, and accordingly frequencies of the resonators are varied at the same time. Accordingly, there is provided a tunable filter that avoids an increase in insertion loss, is high-power resistant, does not cause intermodulation, and allows a center frequency of the filter to be varied steplessly and quickly.

Abstract: Two TE modes whose electric-field rotating planes have a perpendicular relationship are coupled independently of the coupling between two TM modes whose electric-field directions have the same respective perpendicular relationships. In a multimode dielectric resonator device producing four modes: TM01?_x mode, TM01?_y mode, TE01?_x mode, and TE01?_y mode, protrusions (Pe1), (Pe2) are disposed on an upper-layer (La) and a lower-layer of a dielectric core (1) to cause a difference in effective dielectric constants of individual parts through which even-mode and odd-mode electric flux of the TE coupling modes passes. A protrusion (Pc) is formed on a middle-layer Lb of the dielectric core (1) such that the effective dielectric constants of the parts through which even-mode and odd-mode electric flux of the TM coupling modes pass become substantially equal. Thereby, the TE01?_x mode and TE01?_y mode are coupled while restraining the coupling of the TM01?_x mode and the TM01?_y mode.

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 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 ceramic composition includes 100 parts by weight of a main component of the formula: xBaO-y{(1−&agr;)Sm2O3-&agr;Nd2O3}-zTiO2, and as secondary components, about 0.3 part by weight or less of a Mn compound in terms of MnO and about 1 part by weight or less of a Ta compound in terms of Ta2O5, wherein 13≦x≦23; 0<y≦12; 75≦z≦83; 0≦&agr;≦1; and x+y+z=100. Further, about 1.5% by mole or less o3f the Ti element is preferably replaced with Zr. The resulting high frequency dielectric ceramic composition has a high relative dielectric constant (∈r) and a high Q value in a microwave region, can control the temperature coefficient of resonant frequency (&tgr;f) in the vicinity of zero (ppm/°C.), and has a satisfactory thermal shock resistance.

Abstract: A high-frequency dielectric ceramic composition comprises Ba, Ti, Nd, Sm, and Pr as primary components represented by the formula xBaO-yTiO2-z{(1−m−n)Nd2O3-mSm2O3-nPr2O11/3} wherein coefficients x, y, z, m, and n represent molar ratios, x+y+z=1, 0<m≦0.40, 0<n≦0.25, and the coefficients x, y, and z are in an area bounded by points A, B, C and D in a ternary diagram, wherein point A is at (x=0.16, y=0.70, z=0.14), point B is at (x=0.16, y=0.68, z=0.16), point C is at (x=0.13, y=0.68, z=0.19), and point D is at (x=0.13, y=0.70, z=0.17); wherein the composition further comprises a Bi compound in an amount of more than 0 parts by weight to about 9 parts by weight on the basis of Bi2O3 and an Fe compound in an amount of more than 0 parts by weight to about 0.