Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Renesas Electronics Corporation

Hiroyuki Joba

Yoshinori Takahashi

Kazutomi Mori

Noriharu Suematsu

Yukio Ikeda

Ryoji Hayashi

Morishige Hieda

Akira Inoue

Kenichi Maeda

Yoshihito Hirano

Tomohiro Akiyama

Kiyohide Sakai

Tadashi Takagi

Shintaro Shinjo

Mitsuhiro Shimozawa

Hiroaki Nagano

Eiji Taniguchi

Takayuki Ikushima

Chiemi Sawaumi

Mitsuru Motizuki

Kenichi Tajima

Naohisa Takayama

Shintarou Shinjo

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 reception circuit is provided which can detect the beginning of data regardless of a preamble or a unique word contained or not in a received signal and regardless of coding systems for received signals. The reception circuit includes a correlation operation portion that performs a correlation operation to generate a correlation signal while sliding one symbol of reference signal in relation to a received signal. The reference signal goes to a high level during a first half symbol period and goes to a low level during a second half symbol period. The reception circuit further includes: a delay portion that outputs a delay signal by delaying the received signal for a half symbol period in relation to the received signal; and a data beginning timing detection portion that detects a beginning peak timing for the correlation signal as a beginning timing of data contained in the delay signal.

Reception circuit

A frequency converter includes a transistor pair having a first transistor and a second transistor respectively having collector terminals commonly connected to each other and emitter terminals commonly connected to each other, the commonly-connected collector terminals of the transistor pair being connected to a power supply terminal by way of a first resistor, a third transistor having a collector terminal connected to the power supply terminal by way of a second resistor and an emitter terminal connected to the commonly-connected emitter terminals of the transistor pair, a third resistor having an end connected to the commonly-connected emitter terminals of the transistor pair, and another end grounded by way of a constant current source, and an output terminal connected to the commonly-connected collector terminals of the transistor pair. The frequency converter can exhibit an excellent saturation characteristic and an excellent distortion characteristic even when operating from a low voltage and/or a low current.

Frequency converter

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.

High-frequency amplifier

A high frequency amplifier in which a common emitter bipolar transistor is used, and in that a constant current source and a constant voltage source are switched to apply a DC bias to a base terminal of the bipolar transistor in accordance with a power level of a high frequency signal input to the bipolar transistor or a power level of a high frequency signal output therefrom, and a frequency mixer in that a DC bias is applied to a base of at least one of a bipolar transistor for the input of a high frequency signal and a bipolar transistor for the input of a local oscillation wave by using a configuration for applying the DC bias to a base of an amplifying bipolar transistor employed in the high frequency amplifier.

High frequency amplifier and frequency mixer

A mixer circuit includes a local frequency multiplication unit including a pair of transistors having bases receiving local oscillation waves inverted in phase. A reference transistor is differentially connected with the pair of transistors. The pair of transistors and the reference transistor have their emitters connected to a collector of a modulated wave input transistor having a base receiving a modulated wave signal and an emitter connected to a constant current source, and have their collectors connected to a load. The commonly connected collectors of the pair of transistors and the collector of the reference transistor output modulation signals inverted in phase. The sum of currents flowing through the pair of transistors and the reference transistor equals the constant current of the constant current source flowing through the modulated wave input transistor, and the mixer circuit has a gain.

Mixer circuit

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 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.

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Tokyo, Japan

Hiroyuki Joba