%0 Journal Article
%T Analysis and Compensation of the AM-AM and AM-PM Distortion for CMOS Cascode Class-E Power Amplifier
%A Wen An Tsou
%A Wen Shen Wuen
%A Tzu Yi Yang
%A Kuei Ann Wen
%J International Journal of Microwave Science and Technology
%D 2009
%I Hindawi Publishing Corporation
%R 10.1155/2009/597592
%X 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 m CMOS technology, occupies a total die area of 1.6 mm2. 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.
%U http://www.hindawi.com/journals/ijmst/2009/597592/