论文信息 - A 5 GHz class-AB power amplifier in 90 nm CMOS with digitally-assisted AM-PM correction

A 5 GHz class-AB power amplifier in 90 nm CMOS with digitally-assisted AM-PM correction

This paper presents a technique for correcting AM-PM distortion in power amplifiers. The technique uses a varactor as part of a tuned circuit to introduce a phase shift that counteracts the AM-PM distortion of the PA. The varactor is controlled by the amplitude of the IQ baseband data in a feedforward fashion. The technique has been demonstrated in a class-AB CMOS power amplifier designed for WEAN applications and implemented in a 90 nm CMOS process. The PA delivers 10.5 dBm of average power while transmitting at 54 Mbps (64 QAM). The proposed technique is shown to improve the efficiency of the PA by a factor of 2

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