Matsushita Electric Industrial Co., Ltd.

Takehiko Yoneda

Hiromitsu Taki

Kazuhiro Eguchi

Kuniaki Kiyosue

Toshiharu Noguchi

Mitsuo Makimoto

Morikazu Sagawa

Shinichiro Ito

Katsumi Sasaki

Hiromi Tokunaga

Fumio Fukushima

Yoshihiko Takayama

Takuya Fujimaru

Masahiro Yoshimoto

Koji Nishimura

Yasuhiro Izumi

Akiro Yoshida

Ryoichi Makimoto

Tetsjhi Tsujhi

Eiichi Ochiai

A module substrate consists of a substrate mounting electronic parts on one surface thereof, a conductor for electrically conducting the electronic parts mounted on the substrate to the other surface of the substrate, a conductive solder for attaching the conductor to a base substrate movably contacting the other surface of the substrate to electrically connect the electronic parts with the base substrate, and a deformable bushing for holding the conductor to maintain the attachment of the conductor to the base substrate regardless of whether the base substrate is moved.

Face-mounting type module substrate attached to base substrate face to

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.

Filter device for transmitter-receiver antenna

A high-frequency filter of the type having a plurality of resonators open at least at one end thereof, a dielectric board forming an input/output coupling and an interstage coupling, and a case for holding therein the resonators and the dielectric board, wherein the dielectric board is made of a ceramic having a critical stress intensity factor K.sub.1c of not less than 5 MPa.multidot.m.sup.1/2 and a dielectric dissipation factor tan. .delta. of not exceeding 1% in a working frequency band of said high-frequency filter, and wherein electrodes are provided on the dielectric board to form an input/output coupling capacity and an interstage coupling capacity. The high-frequency filter of the foregoing construction has the advantage of an excellent mechanical strength which is capable of withstanding severe mechanical loads such as falling impacts or various stresses.

High-frequency filter having increased mechanical strength

A dielectric ceramic composition represented by the compositional formula: .sub.x BaO-.sub.y TiO.sub.2 -.sub.z Nd.sub.2 O.sub.3 -.sub.t Sm.sub.2 O.sub.3 -.sub.w Bi.sub.2 O.sub.3 so composed as to be in the molar fractions of 0.06.ltoreq.x.ltoreq.0.25, 0.60.ltoreq.y.ltoreq.0.80, 0.05.ltoreq.z.ltoreq.0.18, 0&lt;t.ltoreq.0.07 and 0&lt;w.ltoreq.0.05, provided that x+y+z+t+w=1, and a compositional range of Y&lt;0.68 and Z&gt;0.15 is excluded. As an additive, at least one of Al.sub.2 O.sub.3, ZrO.sub.2, etc. may be added. Part of Ba may be replaced with at least one of Sr, Ca and Mg. The Sm.sub.2 O.sub.3 and Nd.sub.2 O.sub.3 each may have a purity of at least 70 wt. %.

Dielectric ceramic composition

A flat type dielectric filter comprises a substantially U-shaped strip line formed such that each center frequency of spurious output deviates from each odd number frequency times the center frequency of the dielectric filter. That is, it comprises a first portion so curved to form an open loop and two second portions formed to have a larger width than the first portion, each of the second portions being provided to an end of the first portion such that each extends in the opposite direction to the other. In this filter, input/output electrodes confronting ends of U-shaped strip line can be formed on a different layer from the layer where the resonator is formed in order to reduce its size. Reduction of size can be obtained by vertically folding the U-shaped strip line extending horizontally. Terminals of this filter formed on the side surface have a first layer formed on the side surface and a second layer formed on the first layer. The first layer is made of silver, the second layer nickel, or the first layer copper, the second layer solder. This filter has two conducting plates sandwiching dielectric substrates including each resonator, the conducting plate being coated with a epoxy resin or dielectric substance.

Flat type dielectric filter

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.

Dielectric resonator and process for manufacturing the same

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.

Dielectric stepped impedance resonator

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Miyazaki, Japan

Takehiko Yoneda