Title :
A multiphase PWM RF modulator using a VCO-based opamp in 45nm CMOS
Author :
Park, Min ; Perrott, Michael H.
Author_Institution :
Massachusetts Inst. of Technol., Cambridge, MA, USA
Abstract :
A VCO-based RF modulator employing multiphase Pulse Width Modulation (PWM) is presented. The proposed RF modulator encodes the baseband signal into a set of multiphase PWM signals which are generated by a VCO-based opamp. The use of PWM avoids broadband quantization noise which is produced by ΣΔ modulation used in other RFDAC-based modulators. The prototype IC is fabricated in a 45nm CMOS process, consumes 54.3 mW, and has an active area of 0.126 mm2. The measured results satisfy the 802.11g WLAN spectral mask, and EVM for 10-MHz, 64 QAM OFDM at 2.4 GHz is -30 dB.
Keywords :
CMOS integrated circuits; integrated circuit noise; modulators; operational amplifiers; pulse width modulation; radiofrequency integrated circuits; sigma-delta modulation; voltage-controlled oscillators; ΣΔ modulation; 802.11g WLAN spectral mask; CMOS process; QAM OFDM; RFDAC-based modulator; VCO-based RF modulator; VCO-based opamp; baseband signal; broadband quantization noise; frequency 10 MHz; frequency 2.4 GHz; multiphase PWM RF modulator; multiphase PWM signal; multiphase pulse width modulation; power 54.3 mW; size 45 nm; Baseband; Integrated circuit noise; OFDM modulation; Prototypes; Pulse width modulation; Quantization; RF signals; Radio frequency; Signal generators; Space vector pulse width modulation; Multiphase PWM; PWM; Pulse width modulation; RF modulator; RFDAC;
Conference_Titel :
Radio Frequency Integrated Circuits Symposium (RFIC), 2010 IEEE
Conference_Location :
Anaheim, CA
Print_ISBN :
978-1-4244-6240-7
DOI :
10.1109/RFIC.2010.5477255
