Fujitsu Corporation

Mikio Hayashihara

Yasuhiro Murakami

Takashi Tanii

Yasuaki Takeuchi

Yusuke Yamamori

Setsuya Nagaya

Nobuhide Hachiya

Manabu Murakami

Youji Nakata

Masahiko Hirao

Masaaki Saitou

Atsushi Kudo

Kosei Nishimura

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 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

A radio communication circuit includes a transmitter that includes a modulator modulates a signal with a first modulation scheme and a power amplifier amplifies the signal modulated with the first modulation scheme and output the amplified signal and transmits the amplified signal, a receiver that includes a demodulator demodulates the signal output from the transmitter with a second modulation scheme that is different from the first modulation scheme, a pre-distortion compensator compensates occurred upon the amplification of the signal, of the signal input to the transmitter, based on the demodulated signal and a power controller controls supply of power to the receiver and the pre-distortion compensator and stop the supply of the power based on an average power level of the signal output from the transmitter and a peak-to-average power ratio that is a ratio of an instantaneous peak power level to the average power level.

Radio communication circuit and radio communication device

Growing community of inventors

Kawasaki, Japan

Mikio Hayashihara