Dual-core high-swing class-C oscillator with ultra-low phase noise

We propose an ultra-low phase noise oscillator topology that works on the premise that coupling a second identical oscillator core would reduce the overall phase noise by 3 dB. For each core, a high-swing class-C oscillator is used to achieve the lowest phase noise. The realized oscillator is tunable from 4.07-4.91 GHz, drawing 39-59 mA from a 2.15 V power supply. The measured phase noise is -146.7 dBc/Hz and -163.1 dBc/Hz at 3 MHz and 20 MHz offset, respectively, from 4.07 GHz carrier. This is the lowest ever reported phase noise in bulk CMOS IC. This phase noise meets GSM900 normal basestation receiver and mobile station transmitter standards, which have the toughest phase noise requirements in cellular communications.

[1]  Massoud Tohidian,et al.  High-swing class-C VCO , 2011, 2011 Proceedings of the ESSCIRC (ESSCIRC).

[2]  Robert B. Staszewski,et al.  A clip-and-restore technique for phase desensitization in a 1.2V 65nm CMOS oscillator for cellular mobile and base stations , 2012, 2012 IEEE International Solid-State Circuits Conference.

[3]  A. Abidi,et al.  The designer's guide to high-purity oscillators , 2004 .

[4]  C. Hedenas,et al.  A Colpitts Oscillator Design for a GSM Base Station Synthesizer , 2007, 2007 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium.

[5]  A. Mazzanti,et al.  Class-C Harmonic CMOS VCOs, With a General Result on Phase Noise , 2008, IEEE Journal of Solid-State Circuits.

[6]  Robert B. Staszewski,et al.  Third-harmonic injection technique applied to a 5.87-to-7.56GHz 65nm CMOS Class-F oscillator with 192dBc/Hz FOM , 2013, 2013 IEEE International Solid-State Circuits Conference Digest of Technical Papers.

[7]  Pietro Andreani,et al.  A 6.7-to-9.2GHz 55nm CMOS hybrid Class-B/Class-C cellular TX VCO , 2012, 2012 IEEE International Solid-State Circuits Conference.

[8]  R.B. Staszewski,et al.  A digitally controlled oscillator system for SAW-less transmitters in cellular handsets , 2006, IEEE Journal of Solid-State Circuits.