Non-idealities of N-Phase Passive Mixer and Its Canceling Methods

N-phase passive mixer first receivers have gained increasing attention for its inherent low power, wideband impedance match, out-of-band jammer tolerant, low noise Figure and bi-directional transparency for impedance transportation. However, the N-phase passive mixer still suffers from non-idealities such as clock overlap and parasitic introduced downward match frequency point offset (DMFO). In this work, these two non-idealities are analyzed and calculated, and an inductor choke technique for both clock overlap and DMFO cancellation is elaborated. The simulation results show that the proposed technique suppresses clock overlap as big as 3%. Moreover, with a relax requirement for clock overlap, the power of the N-phase clock generator was also optimized. The choke inductor also creates frequency pulling effect which can be simultaneously used to cancel the DMFO with no sacrifice of noise and power.