A K_a-band VCO with low phase noise and wide tuning range using a 90-nm dual-gate device

The design and characterization of a K_a-band 90-nm CMOS voltage-controlled oscillator (VCO) with low phase noise and a wide tuning range is presented in this latter. In this work, the flicker noise (1/f) performance of single- and dual-gate devices is measured and compared. By using the proposed dual-gate device, the VCO design can improve the oscillator phase-noise performance owing to its high output resistance. The measurement results also show a wide frequency tuning range of 3.1 GHz and a low phase noise of below -95 dBc/Hz at an offset frequency of 1 MHz, under a supply voltage of 1.2 V, and a current consumption of 11.0 mA. The proposed VCO exhibits a figure-of-merit of -180 dBc/Hz.