Low frequency noise optimization in Gilbert-cell-based mixers for direct conversion (zero-IF) receivers

This letter analyses the low frequency noise performance in Gilbert-cell-based zero-IF mixers. Several issues for optimizing the flicker noise performance while keeping a good mixer performance in terms of gain, noise figure, and power consumption are introduced in a quantitative manner. A CMOS zero-IF mixer has been fabricated and measured. A flicker noise reduction up to 10.4 dB is achieved at 10 kHz with a power consumption of only 5.4 mW. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 3128–3131, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23940