Fujitsu Corporation

Yusuke Yamamori

Yasuhiro Murakami

Takashi Tanii

Mikio Hayashihara

Yasuaki Takeuchi

Shinichi Kawai

Setsuya Nagaya

Manabu Murakami

Nobuhide Hachiya

Masahiko Hirao

Mutsuhito Ota

A power adjustment method includes: measuring output power that is obtained when input power to be amplified in a linear region is input to a power amplifier configured to amplify input power linearly in the linear region and amplify input power nonlinearly in a nonlinear region; deriving a straight line connecting a measurement point corresponding to the measured output power and a boundary point between the linear region and the nonlinear region in a coordinate plane representing input/output characteristics; acquiring information on an approximate equation that is stored in advance in correspondence with the measured output power, the approximate equation representing a relation between input power and output power in the nonlinear region; and storing information on the derived straight line and the acquired information on the approximate equation in a semiconductor integrated circuit provided at a preceding stage of the power amplifier.

Power adjustment method, computer-readable recording medium and power adjustment apparatus

A wireless communication apparatus includes an amplifying unit that amplifies an input signal that includes signals with different frequencies of a first frequency and the second frequency; a measuring unit that measures a level of inter modulation distortion generated in a signal obtained by the input signal being amplified by the amplifying unit; a determining unit that determines whether the level of the inter modulation distortion measured by the measuring unit is equal to or greater than a regulation value that is previously stored; and a control unit that decreases, when a result of the determination obtained by the determining unit indicates that the level of the inter modulation distortion is equal to or greater than the regulation value, a level of a signal input to the amplifying unit.

Wireless communication apparatus, communication control method, and computer-readable recording medium

A radio communication circuit includes a power amplifier configured to amplify a signal and output the amplified signal, an envelope detector configured to extract an envelope of an input signal inputted to the power amplifier, an offset generator configured to generate an offset value for a power supply voltage to be applied to the power amplifier, based on a distortion amount in an output signal from the power amplifier, and a power supply voltage modulator configured to control the power supply voltage to be applied to the power amplifier based on the envelope extracted and the offset value generated.

Radio communication circuit and radio communication apparatus

Growing community of inventors

Sapporo, Japan

Yusuke Yamamori