A 1.2-V 5.2-mW 20–30-GHz Wideband Receiver Front-End in 0.18- m CMOS

Abstract—This paper presents a low-power wideband receiver front-end design using a resonator coupling technique. Induc-tively coupled resonators, composed of an on-chip transformer and parasitic capacitances from a low-noise amplifier, a mixer, and the transformer itself, not only provide wideband signal transfer, but also realize wideband high-to-low impedance transformation. The coupled resonators also function as a wideband balun to give single-to-differential conversion. Analytic expressions for the coupled resonators with asymmetric loads are presented for design guidelines. The proposed receiver front-end only needs a few passive components so that gain degradation caused by the passive loss is minimized. Hence, power consumption and chip area can be greatly reduced. The chip is implemented in 0.18- m CMOS technology. The experimental result shows that the 3-dB bandwidth can span from 20 to 30 GHz with a peak conversion gain of 18.7 dB. The measured input return loss and third-order intercept point are better than 16.7 dB and 7.6 dBm, respec-tively, over the bandwidth. The minimum noise figure is 7.1 dB. The power consumption is only 5.2 mW from a 1.2-V supply. The chip area is only 0.18 mm. Index Terms—CMOS, common-gate (CG) low-noise amplifier (LNA), inductively coupled resonators (ICRs), low power, low voltage, mixer, resonator coupling network (RCN), wideband. I