High-frequency power amplifier, wireless communication apparatus and wireless communication system

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United States of America Patent

PATENT NO 6605999
APP PUB NO 20020057131A1
SERIAL NO

09984800

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Abstract

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A wireless communication apparatus, which is designed to control the output power without using the power control signal sent from the base station, comprises a high-frequency power amplifier for transmission, a detection means which measures the output power of the power amplifier, and an automatic power control circuit which controls the output power of the power amplifier based on information provided by the detection means. The power amplifier includes an amplifying system which has multiple amplifying stages and is connected between the input and output terminals, and bias circuits which supply bias voltages to transistors of the respective amplifying stages. The bias circuits, which supply the bias voltages to the multiple amplifying stages excluding the last amplifying stage, are each made up of multiple resistors. Each of these bias circuits divides with the resistors the voltage of the entered power control signal to produce a bias voltage, which has a linear response to the control signal for low-power mode, to be fed to the control terminal of the amplifying stage. The bias circuit which supplies a bias voltage to the last amplifying stage includes a circuit which produces a bias voltage which has a nonlinear response to the control signal for high-power mode.

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Patent Owner(s)

Patent OwnerAddress
HITACHI INFORMATION & TELECOMMUNICATION ENGINEERING LTD2-3-3 MINATOMIRAI NISHI-KU YOKOHAMA-SHI KANAGAWA 220-6122

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Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Adachi, Tetsuaki Chisagata, JP 47 653
Akamine, Hitoshi Maebashi, JP 42 665
Furuya, Tomio Sawa, JP 22 453
Matsudaira, Nobuhiro Chigasaki, JP 20 484
Matsushita, Kouichi Komoro, JP 10 282

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