Matsushita Electric Industrial Co., Ltd.

Hiroaki Kosugi

Kaoru Ishida

Hisashi Adachi

Masayuki Miyaji

Shin'ichi Kugou

Toshio Ishizaki

Makoto Sakakura

Fujio Sasaki

Seiichi Yamaguchi

Youichi Morinaga

Toshifumi Nakatani

Shunsuke Hirano

Takashi Enoki

Tomoki Uwano

Hiroshi Haruki

Yoshishige Yoshikawa

Hiroyuki Nakamura

Masakatsu Maeda

Hikaru Ikeda

Hidenobu Kato

Nobuo Fuse

Takayuki Matsumoto

Yoichi Morinaga

Hiroshi Iwai

Toru Yamada

Koichi Ogawa

Hideaki Nakakubo

Toshiaki Nakamura

Takaaki Maegawa

Toshio Obara

Yoshio Horiike

Takeshi Miura

Hideki Yagita

Yasuteru Asakawa

Kazuo Nagao

Hiroyuki Itokawa

Ikuo Ohta

Keiichi Nakayama

Atsushi Yamamoto

Fumio Ito

Toru Matsuura

Osamu Kawasaki

Hiroshi Takahashi

Kenichi Yamada

Koji Takinami

Kenichi Takahashi

Naoki Yuda

Naoki Komatsu

Kunihiko Kanazawa

Yuji Saito

Yukihiko Ise

Tsutomu Matsumura

Kimio Aizawa

Kazuhiko Ikeda

Yukichi Aihara

Atsushi Sasaki

Takayuki Suematsu

Junichi Takada

Wataru Tomiya

Shogo Iizuka

Toshiaki Andoh

Junko Yamamoto

Manabu Yamaguchi

Isao Nasuno

Jyunichi Yoshizumi

Shinichi Kugou

Tooru Sakuragawa

Kouji Hashimoto

Hisanaga Miyoshi

Junichi Yasuno

Makoto Aisaka

Kazuhiko Nakayama

Toshio Sekiguchi

A fraction part control circuit of a frequency synthesizer apparatus including a PLL circuit is of a plural-n-th-order delta-sigma modulator circuit for controlling a fraction part of a number of frequency division to a variable frequency divider of the PLL circuit. An adder adds data of the fraction part to an output data from a multiplier and outputs the resultant data to a quantizer through a second-order integrator. The quantizer quantizes input data with a quantization step and outputs the quantized data to the multiplier through a feedback circuit. The quantized data is used as data of the controlled fraction part. The multiplier multiplies data from the feedback circuit by the quantization step and outputs the resultant data to the adder. The fraction part control circuit periodically changes the data of the fraction part, thereby setting a frequency of an output signal from a VCO according to an average value of the period.

Frequency synthesizer apparatus equipped with fraction part control circuit, communication apparatus, frequency modulator apparatus, and frequency modulating method

An antenna duplexer has an antenna terminal;

Antenna duplexer and mobile communication device using the same

Display-antenna integral structure and communication apparatus

A balun design incorporating the functions of a splitter (combiner) which can be employed in a high power amplifier circuit configuration. The balun is formed of a dielectric multilayer board with conductor patterns on each conductor pattern layer. The balun includes the propagation of a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal. The balun provides the output signals at the first and second opposite-phase output terminals 180&deg; out of phase employing through holes in the main line and coupling lines for promoting electromagnetic coupling therebetween.

Power splitter/combiner circuit, high power amplifier and balun circuit

A high power amplifier has a first balun propagating a half of an input signal to an in-phase output terminal, and also propagating a fourth of the input signal to first and second opposite-phase output terminals, the signal propagated to the first and second opposite-phase output terminals lagging 180 degrees behind the signal propagated to the in-phase output terminal; first and second power amplifier circuits connected to the first and second opposite-phase output terminals of the first balun and having the same characteristics; a third power amplifier circuit connected to the in-phase output terminal of the first balun and having output power substantially twice as much as the output power of the first or second power amplifier circuit; and a second balun having first and second opposite-phase input terminals for receiving the outputs of the first and second power amplifier circuits, having an in-phase input terminal for receiving the output of the third power amplifier circuit, combining the outputs of the first, second and third power amplifier circuits, and propagating combined output.

Power splitter/combiner multi-layer circuit

To reduce the size of a multi-carrier transmitter circuit for a mobile communication base station, by suppressing instantaneous peak output power to a small value with respect to a wide-band signal of a few MHz to tens of MHz so that the peak factor of a multi-carrier signal is reduced. In a multi-carrier transmitter circuit for modulating carriers with corresponding input signals to generate modulated signals and then multiplexing said modulated signals and outputting a multiplexed signal, the multi-carrier transmitter circuit is equipped with carrier generators - to -n for generating each said carrier, modulators - to -n for modulating each carrier with each input signal and outputting said modulated signal, an adder for multiplexing said modulated signals and outputting the multiplexed signal, variable attenuators - to -n for directly or indirectly adjusting a level of each input signal, phase detectors - to -n for detecting a phase of each carrier, and a control circuit for controlling the variable attenuators - to -n in accordance with the phase of each carrier.

Multi-carrier transmitter circuit and communication equipment

A portable celullar phone apparatus includes a portable cellular phone and an external adapter for a portable cellular phone. It is possible to suppress an increase in output power of a portable cellular phone transmit amplifier due to a loss at a transmit switch associated with use of an external transmitting antenna by coupling a first output of the transmit switch to a portable cellular phone transmit amplifier and coupling a second output of the transmit switch to an input of a transmit amplifier part of a portable cellular phone external adapter. Deterioration of a NF of a receiving system due to a loss at a receive switch when using an external receiving antenna may be reduced by coupling a first input of a receive switch to a portable cellular phone receive amplifier and coupling a second input of the receive switch to an output of a receive amplifier part of the portable cellular phone external adapter.

External adapter for a portable cellular phone

The invention provides a high-speed PLL frequency synthesizer in which the frequency of a reference signal can be made larger than a frequency interval of an external output with a simple configuration. An n-th harmonic of an output of a voltage-controlled oscillator is caused to pass through a band pass filter. The frequency of an output of the band pass filter is divided by M in a variable frequency divider. The phase of an output of the variable frequency divider is compared with that of the reference signal in a phase comparator. An output of the phase comparator is smoothed by a loop filter. The output of the voltage-controlled oscillator is controlled by an output of the loop filter. The fundamental wave of the output of the voltage-controlled oscillator is caused to pass through another band pass filter, and then output to the outside. At this time, the frequency of the reference signal is n times a frequency interval of the fundamental wave of the output of the voltage-controlled oscillator.

PLL frequency synthesizer

The present invention concerns a radio circuit including a local oscillator, a first receive frequency converter, a frequency divider and a demodulator. A receive signal and an output of the local oscillator are input to the first receive frequency converter. The receive signal is converted into a first intermediate signal by the first receive frequency converter, and the first intermediate frequency signal is input to the demodulator. The output of the local oscillator is frequency-divided by the frequency divider and also input to the demodulator. The signal converted into the first intermediate frequency is demodulated into a baseband signal by the demodulator.

Radio circuit having a local oscillator frequency which differs from the transmit frequency or the receive frequency and mobile radio apparatus

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

Power amplifier, power control method for power amplifier, and communication equipment

A feedforward amplifier includes a power divider for dividing the input signal into first and second signals. The first signal is processed in a first path that includes, in sequence, a first vector adjuster, a main amplifier, a directional coupler and a delay circuit. The second signal is delayed in a second path that includes, in sequence, another delay circuit, a first power combiner and an auxiliary amplifier block. The first power combiner combines the first signal, by way of a coupling port from the directional coupler, with the second signal to provide a combined signal into the auxiliary amplifier block. The auxiliary amplifier block further divides the second signal into two divided signals, each having a respective non-overlapping frequency band. The two divided signals are respectively vector adjusted, amplified, and then recombined. The recombined signal is then recombined with the processed signal in the first path to provide the desired output signal.

Feedforward amplifier

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Hirakata, Japan

Hiroaki Kosugi