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. A prototype double-balanced mixer in 0.13 μm CMOS is fabricated as a proof of concept. The circuit achieves a flicker-noise corner almost an order-of-magnitude lower than that of a standard implementation without compromising the linearity, gain, or power consumption.