28GHz RX frontends with sub-harmonic-based mm-wave LO Generation in 16nm FinFET

Power consumption of integrated mm-wave receiver (RX) arrays is a critical barrier for evolution from mm-wave phased arrays to full mm-wave MIMO arrays that support digital multi beam-forming. In this paper, we propose two low-power mm-wave 16nm FinFET RX front-ends that leverage a novel power and area-efficient multi-phase LO approach to enable low-power clock distribution. In the first approach, an injection locked oscillator uses multi-phase signals to produce desired mm-wave LO for the RF mixers. In the second approach, a novel sub-harmonic mixer is used to down-convert the mm-Wave signal using a multi-phase LO at 1/5th the input mm-wave frequency. The two RX implementations achieve 55dB (53dB) gain across an input bandwidth of 23-26GHz with in-band noise figure of 5.4dB (5dB) and consuming 82mW (67mW) power per element. A key contribution is state-of-the-art power consumption in LO distribution of 27mW (24mW) making these approaches amenable to large-scale phased arrays.