Title :
A Dual-Power-Mode Output Matching Network for Digitally Modulated CMOS Power Amplifier
Author :
Yumi Lee ; Songcheol Hong
Author_Institution :
Dept. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol. (KAIST), Daejeon, South Korea
Abstract :
A dual-power-mode output matching network for a digitally modulated power amplifier (DMPA) to improve low power efficiency is proposed. The DMPA with output matching network is fully integrated using a 0.13- μm RF CMOS process. The matching network incorporates a switched transformer and capacitors. The switched transformer is proposed for tuning its inductance to have two power modes. It is designed to minimize losses due to parasitic components of the switch transistor. The DMPA has a 12-bit resolution to enable a wide digital transmit power control (TPC) range. The peak power is 29.3 dBm with 34% efficiency. The efficiency at 16 dBm is improved from 8% to 13% by using the output matching network. Simple static predistortion helps the DMPA reconstruct 27.9-dBm WCDMA signals at 1.95 GHz with 31% efficiency. The digital TPC range is 25 dB.
Keywords :
CMOS analogue integrated circuits; low-power electronics; power amplifiers; radiofrequency amplifiers; transformers; DMPA; RF CMOS process; WCDMA signals; digital TPC range; digital transmit power control range; digitally modulated CMOS power amplifier; digitally modulated power amplifier; dual-power-mode output matching network; efficiency 31 percent; efficiency 34 percent; efficiency 8 percent to 13 percent; frequency 1.95 GHz; inductance; low power efficiency; parasitic components; power modes; size 0.13 mum; static predistortion; switch transistor; switched capacitors; switched transformer; word length 12 bit; CMOS integrated circuits; Impedance; Impedance matching; Inductance; Power generation; Switches; Transistors; CMOS power amplifier (PA); WCDMA; digitally modulated power amplifier (DMPA); dual-power-mode matching network; polar transmitter; switched transformer; tunable matching network;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2013.2246525
