Circuit techniques for CMOS multiple-antenna transceivers

Circuit techniques are described for multiple-antenna transceivers. A device desensitization technique aimed at simultaneously realizing the optimum noise and input match in LNA circuits is followed by a transformer-coupling technique in common-gate LNA circuits that reduces NF and power. Next, a Colpitts VCO improves start-up and maintains excellent phase-noise performance. Finally, a Cartesian combining method applied to MIMO transceivers is overviewed.