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This paper presents a 60-GHz CMOS direct-conversion Doppler radar RF sensor with a clutter canceller for single-antenna noncontact human vital-signs detection. A high isolation quasi-circulator (QC) is designed to reduce the transmitting (Tx) power leakage (to the receiver). The clutter canceller performs cancellation for the Tx leakage power (from the QC) and the stationary background reflection clutter to enhance the detection sensitivity of weak vital signals. The integration of the 60-GHz RF sensor consists of the voltage-controlled oscillator, divided-by-2 frequency divider, power amplifier, QC, clutter canceller (consisting of variable-gain amplifier and 360^\circ phase shifter), low-noise amplifier, in-phase/quadrature-phase sub-harmonic mixer, and three couplers. In the human vital-signs detection experimental measurement, at a distance of 75 cm, the detected heartbeat (1–1.3 Hz) and respiratory (0.35–0.45 Hz) signals can be clearly observed with a 60-GHz 17-dBi patch-array antenna. The RF sensor is fabricated in 90-nm CMOS technology with a chip size of \2 mm\times \2 mm and a consuming power of 217 mW. [ABSTRACT FROM PUBLISHER]

In this letter, a 75–110-GHz W-band high-linearity traveling-wave single-pole-double-throw switch in 90-nm CMOS GUTM 1P9M is presented. Compared with the traditional traveling-wave switch with negative body-biasing technique, the proposed design applies the negative biasing to the gate terminals simultaneously. Therefore, the third-order intermodulation product is significantly reduced. The measured results show that the insertion loss is less than 3.4 dB, return loss is better than 10 dB, and Tx-to-Rx isolation is higher than 40 dB, respectively. For the linearity of the switch, the measured IP1dB is higher than 15 dBm and IIP3 is 37.1 dBm at 94 GHz, respectively. The proposed switch presents good performance of insertion loss, isolation, IP1dB, and IIP3, among the compared millimeter-wave CMOS switches. [ABSTRACT FROM PUBLISHER]