Envelope-tracking common-drain CMOS power amplifier with a switching-only supply modulator for LTE applications. (February 2018)

• Record Type: Journal Article
• Authors: Zavarei, Mohammad Javad; Taherzadeh-Sani, Mohammad
• Is Part Of: Microelectronics journal. Volume 72(2018)
• Page Start: 24
• Page End: 31
• Publication Date: 2018-02
• Subjects: CMOS power amplifier -- Envelope shaping -- Envelope tracking -- Long-Term Evolution (LTE) -- Supply modulator; Microelectronics -- Periodicals; Microélectronique -- Périodiques; Microelectronics; Electronic journals; Journals - contents and abstracts; Periodicals; 621.3805
• DOI: 10.1016/j.mejo.2017.11.013
• Languages: English
• ISSNs: 0959-8324

Abstract

Abstract: This paper proposes an integrated envelope tracking CMOS power amplifier for LTE application. It is shown in the paper that a common-drain power amplifier has improved linearity performance and less switching-ripple leakage of the supply voltage, as compared to its common-source counterpart. Hence, the proposed envelope tracking power amplifier is designed with a common-drain structure and post-simulated in a 0.18 μm CMOS process. By utilizing the common-drain structure, the supply modulator can be implemented using a switching-only regulator, and neither a linear regulator nor a hybrid technique is required. For a signal at 1.85 GHz with a 5-MHz bandwidth and 6.5 dB PAPR, the CMOS envelope tracking power amplifier achieves a power added efficiency of 30% and an Adjacent Channel Leakage Power Ratio (ACLR) of −32 dBc at an average output power of 22 dBm. By employing envelope tracking technique, the power added efficiency is improved by up to 5 dB, as compared to that of the stand-alone power amplifier.