A noise cancellation technique in active RF-CMOS mixers

Based on the physical understanding of noise mechanisms in active mixers, a noise cancellation technique to reduce the flicker noise contribution of the switches in a Gilbert-type mixer is presented. For the proof of concept, a prototype double-balanced mixer in 0.13 μm CMOS is fabricated. The circuit achieves a flicker noise corner of almost an order of magnitude lower than that of a standard implementation, without any penalty in the linearity, gain, or power consumption.