A novel feedback low phase noise Ka-band push-push CMOS VCO

A Ka-band cross-coupled push-push LC Voltage Controlled Oscillator (VCO) with a novel feedback configuration is proposed to improve the phase noise performance. The main idea of the proposed novel feedback configuration is to increase negative conductance and cancel the loss conductance of LC tank. Conductance of LC tank decreases Q-value. Therefore, decreased total conductance increases Q-value in LC tank, which improves phase noise performance of the proposed VCO. The VCO is simulated in 0.18 ¿m CMOS technology with 1.8 V voltage supplied. The output power is -7.95 dBm at 24 GHz. The phase noise shows about -111.0 dBc/Hz at 1 MHz offset frequency. The tuning range is observed about 2.29 GHz from 22.5 GHz to 24.79 GHz.