Matsushita Electric Industrial Co., Ltd.

Toshiaki Nakamura

Toshio Ishizaki

Minoru Tachibana

Akira Enokihara

Yuki Satoh

Toru Yamada

Yasunao Okazaki

Takehiko Yamakawa

Makoto Sakakura

Michio Okajima

Kunihiko Minami

Masami Hatanaka

Yuji Saka

Hiroyuki Nakamatsu

Hisashi Adachi

Hiroaki Kosugi

Hideaki Nakakubo

Hiroshi Kushitani

Yoshihiro Nakagawa

Kimio Aizawa

Takashi Fujino

Atsushi Sasaki

Hideki Namba

Hiroyuki Nakamura

Koji Hashimoto

Koichi Ogawa

Koji Takinami

Toshimitsu Matsuyoshi

Tomoki Uwano

Takashi Nagata

Hideyuki Miyake

Nobuhiro Takimoto

Jyunichi Yoshizumi

Hiroyuki Itokawa

Ikuo Ohta

Junichi Yoshizumi

A high-frequency circuit device includes a dielectric member, a shielding conductorsurrounding the dielectric member, a support memberfor fixing and supporting the dielectric member, and a pair of transmission lineseach of which is formed of a microstrip-line. Each of the transmission lines includes a substrateformed of a dielectric material, a strip conductor, and an earth conductor layer. An end portion of the strip conductorfaces part of the dielectric memberand functions as a coupling probe for input/output coupling. Each of the transmission linesis formed of a strip line, a mictostrip line, a coplanar line or the like, and has low-loss when connected to a circuit board.

High-frequency circuit device and high-frequency circuit module

An antenna duplexer has an antenna terminal;

Antenna duplexer and mobile communication device using the same

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.

In-band-flat-group-delay type dielectric filter and linearized amplifier using the same

A dielectric resonator filter comprises dielectric resonators, an enclosure having a main body, a lid, and partition walls, interstage-coupling tuning windows, interstage-coupling tuning bolts, input/output terminals, and input/output coupling probes. Resonance-frequency tuning members each composed of a conductor plate and a bolt coupled integrally thereto are attached to the enclosure lid. Undesired-mode suppressing means such as rings attached to the bolts of the resonance-frequency tuning members or bolts attached to the conductor plates or to the enclosure lid are disposed in an undesired-mode excitation space, whereby the occurrence of a disturbed characteristic in the pass band (or stop band) is suppressed.

Dielectric resonator filter

In order to prevent filter characteristics from being deteriorated due to generation of a spurious pulse is unnecessary resonance at a high level in a passing band at the frequency in a microwave region used in a portable telephone system or the like, at least two types of dielectric resonators having different frequency characteristics in unnecessary harmonic modes except for a main mode near the passing band of a filter are arranged in spaces partitioned by partition walls in a shielding unit constituted by a metal case and a lid, so that a dielectric filter which can obtain preferable spurious suppressing characteristics.

Dielectric filter

A dielectric resonator of the invention includes a cavity having a first threaded hole; a dielectric block provided in the cavity; a coupling device coupled with an electromagnetic field produced in the cavity; a frequency tuning member having a screw portion which is spirally engaged with the first threaded hole of the cavity, a distance between the dielectric block and the frequency tuning member being changed by rotating the frequency tuning member, for tuning a resonance frequency of the cavity depending on the distance; and fixing means for fixing a relative positional relationship between the frequency tuning member and the cavity, wherein the fixing means prevents the frequency tuning member from rotating due to a frictional force caused between the first threaded hole of the cavity and the screw portion of the frequency tuning member, the fixing means including a lock nut having a second threaded hole which is spirally engaged with the screw portion of the frequency tuning member.

Dielectric resonator having a frequency tuning member spirally engaged with the cavity

A method for generating a local oscillation signal comprising two separate frequency converters, of which one frequency converter includes an output unit for generating an internal output signal to be used for its frequency conversion, and the other frequency converter employs the same internal output signal from the output unit as the local oscillation signal.

Transmission system, transmission/reception system, and local oscillator to be used in the same

The dielectric notch filter of the invention includes: a transmission line for transmitting a high-frequency signal; input and output terminals provided at both ends of the transmission line; a ground conductor for supplying a ground potential; and a dielectric resonator connected to the ground conductor and the transmission line. The dielectric notch filter further includes an impedance matching element connected to the ground conductor and the transmission line in parallel with the dielectric resonator. The dielectric resonator includes: a cavity connected to the ground conductor; a dielectric block provided in the cavity; a coupling device coupled with an electromagnetic field, produced in the cavity; and a coupling adjusting line for connecting the coupling device to the transmission line and for adjusting the degree of electromagnetic coupling.

Dielectric resonator, dielectric notch filter, and dielectric filter with optimized resonator and cavity dimensions

A voltage-controlled resonator is fabricated by laminating, one on top of the other, a first dielectric which has a resonant circuit and on the upper surface of which a variable-capacitance element is mounted, and a second dielectric which has a through-hole formed in a position thereof corresponding to the position of the variable-capacitance element and which has a dual function of shielding and resonant frequency tuning. With this structure, the height of the resonator can be further reduced compared with the prior art while retaining the shielding effect, and moreover, further precise resonant frequency tuning can be accomplished as compared with the prior art.

Voltage-controlled resonator, method of fabricating the same, method of

Growing community of inventors

Nara, Japan

Toshiaki Nakamura