This paper proposes a low-power and low phasenoise
current-reuse quadrature VCO using a combination of capacitor
coupling and transformer feedback technique. Compared
with conventional active coupled QVCO, the proposed QVCO
can achieve a low phase noise characteristics with low power
consumption.
The proposed QVCO was fabricated in 180nm CMOS process
technology and showed a 1MHz offset phase noise of -127 dBc/Hz
at 3.97 GHz. The power consumption was 6.26mW with 1.0V
supply voltage and a figure of merit (FOM) of the proposed
QVCO was -191 dBc/Hz.