60-GHz, 9-µW wake-up receiver for short-range wireless communications

We present an ultra-low power 60-GHz band wake-up receiver (WuRx) designed and fabricated with a 0.18-μm RF CMOS low-cost technology. The WuRx consists of an envelope detector, high-gain baseband amplifier, and clock and data recovery (CDR) circuit. Subthreshold-operated offset-voltage cancellers are used in the detector and baseband amplifier. The envelope detector can operate for an on-off keying (OOK) signal with a low bit-rate baseband and 60-GHz carrier, which is higher than the cutoff frequency (f_T) of 0.18-μm MOSFETs. This is because the f_T defines the maximum operating bit-rate of the baseband signal. The CDR circuit is composed of a clock recovery circuit using an injection-locked oscillator, short pulse generator, and D-type flip/flop. The fabricated WuRx successfully operates with power consumption of only 9 μW from a 1.5-V supply and a high sensitivity of -68 dBm for a 350-kbit/s OOK signal with a 60-GHz carrier. The CMOS die area is 1.09 mm². This is the first successful fabrication of a 60-GHz WuRx.