Approaches to Nonoverlapping Clock Generation for RF to Millimeter-Wave Mixer-First Receivers

N-phase mixer-first receivers are an ideal choice for broadband frequency-selective receivers. These receivers can now operate near millimeter-wave frequencies using fast-rising four-phase clock generation in advanced CMOS. This paper compares four-phase clock-generation approaches used in two high-frequency mixer-first receivers-a polyphase filter-based scheme as part of a 20–30 GHz receiver and a divider-based scheme as part of 5–31 GHz receiver. We discuss circuits for quadrature and 25% duty-cycle generation and compare clock performance in terms of area, power, quadrature accuracy, and receiver metrics. Both receivers demonstrate typical noise figure below 8 dB and conversion gains above 18 dB.