Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Kazutomi Mori

Yukio Ikeda

Shintaro Shinjo

Hiroyuki Joba

Akira Inoue

Tadashi Takagi

Noriharu Suematsu

Morishige Hieda

Yoshinori Takahashi

Akira Ohta

Shintarou Shinjo

Koji Yamanaka

Yoshihito Hirano

Tomohiro Akiyama

Kiyohide Sakai

Teruyuki Shimura

Ryoji Hayashi

Mitsuhiro Shimozawa

Hiroaki Nagano

Kazuhiko Nakahara

Kenichi Tajima

Hiroaki Seki

Mitsuru Motizuki

Naofumi Yoneda

Masatoshi Nakayama

Moriyasu Miyazaki

Kazunori Takahashi

Masatake Hangai

Yukihiro Tahara

Kazuyoshi Inami

Akio Iida

Kousei Maemura

Kazuhiro Iyomasa

Kazuhisa Yamauchi

Kenichi Miyaguchi

Norio Takeuchi

Masaharu Hattori

Toshiyuki Horie

Hiroshi Ikematsu

Tetsu Ohwada

Michiaki Kasahara

Hideyuki Oh-Hashi

Toshio Okuda

Yutaka Ozaki

Fumimasa Kitabayashi

Hiromasa Nakaguro

Kenichiro Choumei

Hiroomi Ueda

An array antenna apparatus in which an SN ratio is improved. Antenna elements having transmission modules, respectively, are arranged in plurality, wherein the plurality of transmission modules respectively have transmission signal generators that each output a transmission intermediate frequency signal, local oscillation signal generators that each output a local oscillation signal, and transmission mixers that each mix the transmission intermediate frequency signal and the local oscillation signal with each other, thereby to carry out frequency conversion to a transmission high frequency signal. A reference signal source inputs a reference signal to the transmission signal generators and the local oscillation signal generators. The transmission intermediate frequency signal and the local oscillation signal are synchronized with each other by the reference signal.

Array antenna apparatus

A transmission module including a power supply voltage control unit that sets a power supply voltage to the high frequency amplifier in a variable manner, and a control circuit that controls an amplitude control unit, a phase control unit and the power supply voltage control unit. The control circuit and the power supply voltage control unit control the power supply voltage in accordance with an output power of the high frequency amplifier. The transmission module can carry out not only phase control but also amplitude control in a continuous manner, while suppressing amplitude and phase variation, and a high frequency amplifier in the transmission module is made highly efficient. In addition, a large directional gain, a low side lobe level and a low power consumption are achieved, as a phased array antenna apparatus using a transmission module.

Transmission module and phased array antenna apparatus

A multiport amplifier and a wireless device using the same are obtained in which isolation among output terminals is improved, whereby the quality of communication is improved. The multiport amplifier includes an input hybrid, an output hybrid, a plurality of amplifiers and a plurality of gain and phase control circuits that are inserted between the input hybrid and the output hybrid, a plurality of output coupling circuits that are inserted between the output hybrid and a plurality of output terminals so that they receive output extraction signals corresponding to a plurality of output signals, and a feedback circuit including a frequency selection circuit that is inserted between the plurality of output coupling circuits and the plurality of gain and phase control circuits.

Multiport amplifier and wireless device using the same

Provided is a high frequency amplifier including two amplifying elements of different element sizes connected in parallel and switching the amplifying elements in accordance with a level of output power. In particular, the high frequency amplifier includes an output matching circuit for matching to characteristic impedance (50 ohms) both when the output power is high and low, and increasing impedance when the turned-off amplifying element is viewed from a connection node on an output side of the two amplifying elements. Consequently, characteristics such as high output power and high efficiency can be achieved and it is possible to prevent an amplified high frequency signal from passing around to a matching circuit on a turned-off amplifying element side.

High frequency amplifier

A high-power amplifier changes matching conditions of an output matching circuitconnected between a final stage amplifying elementand an output terminalin response to the output power of the amplifying element. Thus, the efficiency at low output power can be greatly improved without reducing the efficiency at the maximum output. Besides, since it is not necessary to load a DC-DC converter, an increase in size or cost can be prevented.

High-power amplifier

A high frequency amplifier includes a constant voltage driven amplifierusing as its amplifying element a bipolar transistorwith its base biased by a constant voltage, and a constant current driven amplifierusing as its amplifying element a bipolar transistorwith its base biased by a constant current. The idle current of the constant current driven amplifieris set at a low value. In accordance with the idle current, the idle current of the constant voltage driven amplifieris adjusted, and the two amplifiers are combined in parallel.

High-frequency amplifier

The present invention includes: a first main waveguide; a T-branch circuitconnected thereto; a first low-pass filterconnected thereto; a band-pass filterconnected to the first T-branch circuit; a first converterconnected to the first low-pass filterfor converting transmission lines between a waveguide and a microwave integrated circuit; an amplifierconnected to the first converter and structured by the microwave integrated circuit; a second converterconnected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filterconnected thereto; a second T-branch circuitconnected to the second low-pass filter and the band-pass filter; and a second main waveguideconnected to the second T-branch circuit.

High frequency module and antenna device

A high-frequency amplifying unitin which a steep gain variation developed according to a change in the amplitude of input high-frequency signal is suppressed is provided. It amplifies an input high-frequency signal with a plurality of transistors-to-N at the same time a measuring circuitmeasures amplitude of the input high-frequency signal, and a bias control circuitcontinuously controls a bias applied to each transistors-to-N according to the value of amplitude measured by the measuring circuit. Thus it is possible to suppress a steep gain variation produced according to a variation in the amplitude of input high-frequency signal.

A high-frequency semiconductor device according to the present invention achieves improvements in degradation of noise characteristics and a reduction in gain, and an improvement in reduction in power efficiency while suppressing a concentration of a current to multifinger HBTs. In the multifinger HBTs constituting a first stage and an output stage of an amplifier, basic HBTsthat constitute the multifinger HBTcorresponding to the first stage, are each made up of an HBTand an emitter resistorconnected to the corresponding emitter of the HBT, whereas basic HBTsthat constitute the multifinger HBTcorresponding to the output stage, are each comprised of an HBTand a base resistorconnected to the corresponding base of the HBT. The high-frequency semiconductor device according to the present invention is useful as a high output power amplifier used in satellite communications, ground microwave communications, mobile communications, etc.

High-frequency semiconductor device

An inter-stage matching circuit comprises a one-stage high pass filter type matching unit and a one-stage low pass filter type matching unit serially connected with each other.

Multistage amplifier

Between resistors and an NPN bipolar transistor are interposed PNP bipolar transistors forming a current mirror that uses a collector current of the NPN bipolar transistor as a reference current, and determines a collector current of an NPN bipolar transistor . This makes possible to design a size ratio A of the PNP bipolar transistors so as to approximate a voltage drop &Dgr;Vb to a value close to zero, and to suppress the voltage drop &Dgr;Vb of the base voltage Vb accordingly to achieve a high power output and high efficiency when a high frequency input signal Pin increases and generates a base rectified current.

A bias condition of at least one amplifier among amplifiers other than a last-stage amplifier is set in consideration of the relation between an idle current and a saturation current.

A miniaturized phase shifter and a multi-bit phase shifter are provided, in which filters are constructed using capacitors at FET pinch-off and pass phase can be shifted by turning the FET on and off, the phase shifter including: a first FET having a drain electrode connected to an input terminal and a source electrode connected to an output terminal; a second FET, in which one of a drain electrode and a source electrode thereof is connected to the source electrode of the first FET and the other is connected to ground via a first inductor; and a third FET, in which one of a drain electrode and a source electrode thereof is connected to the drain electrode of the first FET and the other is connected to ground via a second inductor.

Phase shifter and multibit phase shifter

A high-frequency amplifying unit in which a steep gain variation developed according to a change in the amplitude of input high-frequency signal is suppressed is provided. It amplifies an input high-frequency signal with a transistor at the same time a measuring circuit measures amplitude of the input high-frequency signal, and a bias control circuit continuously controls a bias applied to the transistor according to the value of amplitude measured by the measuring circuit . Thus it is possible to suppress a steep gain variation produced according to a variation in the amplitude of input high-frequency signal.

A T-type circuit having series resistors and a parallel resistor is arranged on the outside of an amplifier, a signal is amplified in the amplifier while stabilizing the signal by using the T-type circuit functioning as a stabilizing circuit, and the amplified signal is output. In this case, values of the series resistors and the parallel resistor of the T-type circuit are determined so as to set an output load impedance obtained by seeing the output side of the high-frequency amplifier from the amplifier to a value near to or slightly lower than a value of the conjugate complex impedance of an output impedance of the amplifier. Therefore, the output signal having a high output electric power and a low distortion can be obtained in the high-frequency amplifier while keeping a gain and a noise characteristic of the high-frequency amplifier.

High-frequency amplifier and high-frequency multistage amplifier

Growing community of inventors

Tokyo, Japan

Kazutomi Mori