Quadrature VCO using the composite right-/left-handed dual-resonance resonator

A dual-band quadrature voltage-controlled oscillator (QVCO) has been studied and implemented in the TSMC 90 nm 1P9M CMOS technology. The proposed QVCO comprises two complementary cross-coupled dual-resonance VCOs and 4 capacitors in a ring for coupling the two differential VCOs. The QVCO actually uses an LC-based composite transmission-line resonator. The die area of the QVCO is 0.831×0.97 mm². At the supply voltage of 1.1 V, the total power consumption is 2.75 mW. The free-running frequency of the QVCO is tunable from 8.77/3.68 GHz to 9.12/4.16 GHz as the tuning voltage is varied from 0.0/0.6 V to 0.5/1.1 V. The measured phase noise at 1 MHz frequency offset is -120.39/-118.75 dBc/Hz at the oscillation frequency of 8.79/3.847 GHz and the figure of merit (FOM) of the proposed QVCO is -194.86/-186.05 dBc/Hz.