Analysis and Compensation of the AM-AM and AM-PM Distortion for CMOS Cascode Class-E Power Amplifier. (23rd February 2010)

• Record Type: Journal Article
• Authors: Tsou, Wen An; Wuen, Wen Shen; Yang, Tzu Yi; Wen, Kuei Ann
• Other Names: Lu Liang-Hung Academic Editor.
• Is Part Of: International journal of microwave science and technology. Volume 2009(2009)
• Publication Date: 2010-02-23
• Subjects: Radio frequency -- Periodicals; Microwave circuits -- Periodicals; Radiofréquences; Circuits pour micro-ondes; Microwave circuits; Radio frequency; Periodicals; Electronic journals; 621.3813
• DOI: 10.1155/2009/597592
• Languages: English
• ISSNs: 1687-5826

Abstract

Abstract : Analysis and compensation methodology of the AM-AM and AM-PM distortion of cascode class-E power amplifiers are presented. A physical-based model is proposed to illustrate that the nonlinear capacitance and transconductance cause the AM-AM and AM-PM distortion when modulating the supply voltage of the PA. A novel methodology that can reduce the distortion is also proposed. By degenerating common-gate transistor into a resistor, the constant equivalent impedance is obtained so that the AM-AM and AM-PM distortion is compensated. An experimental prototype of 2.6 GHz cascode class-E power amplifier with the AM-AM and AM-PM compensation has been integrated in a 0.18 μ m CMOS technology, occupies a total die area of 1.6 mm 2 . It achieves a drain efficiency of 17.8% and a power-added efficiency of 16.6% while delivering 12 dBm of linear output power and drawing 31 mA from a 1.8 V supply. Finally, a co-simulation result demonstrated that, when the distortion of the PA has been compensated, the EVM is improved from −17 dB to −19 dB with an IEEE802.11a-like signal source.