Performance bounds and measurements for AC-coupled direct-conversion transceivers under the presence of 1/f noise

Design considerations and trade-offs for AC-coupled direct-conversion transceivers that suffer from 1/f noise are explored. CMOS technology provides a cost-effective solution for RF direct-conversion applications, but it suffers from 1/f noise. Theoretical bounds and simulation results were complemented by error vector magnitude (EVM) measurements on a differential CMOS LNA and mixer. The results verified that the system performance is less sensitive to the AC-coupling corner frequency than the 1/f corner frequency. Moreover, simulations showed that the effect of the AC-coupling corner frequency is less significant for lower SNR.