The Quest For Low Phase Noise

Dec. 3, 2009

Phase noise can degrade the performance of the most sophisticated wireless communications system, especially when it is based on digital modulation. It is no surprise, then, that the best paper award for a nominal measurement conference, the November ARMMS Conference (www.armms.org), should go to a presentation on achieving lower phase noise with a frequency synthesizer using a voltage-controlled oscillator (VCO). The recognition went to Alexander Chenakin of Phase Matrix, Inc., who explained how to cut phase noise for a VCO even when multiplying its frequencies.

Chenakin, interviewed earlier this year in Microwaves & RF, reported on low phase noise of -122 dBc/Hz offset 10 kHz from a 10-GHz carrier. Normally, a YIG oscillator is needed for such low-noise performance. But this design was based on a VCO, with its inherently faster (than a YIG) tuning speed. The low-phase-noise results for the VCO-based synthesizer, of course, support a wide range of test equipment, including spectrum analyzers and signal generators, not to mention all those digitally modulated wireless communications systems.

About the Author

Jack Browne

Technical Contributor

Jack Browne, Technical Contributor, has worked in technical publishing for over 30 years. He managed the content and production of three technical journals while at the American Institute of Physics, including Medical Physics and the Journal of Vacuum Science & Technology. He has been a Publisher and Editor for Penton Media, started the firm’s Wireless Symposium & Exhibition trade show in 1993, and currently serves as Technical Contributor for that company's Microwaves & RF magazine. Browne, who holds a BS in Mathematics from City College of New York and BA degrees in English and Philosophy from Fordham University, is a member of the IEEE.