Low-Power and Wideband LC-VCO for WiMAX in CMOS Technology

This work presents an ultralow phase-noise and wide turning-range voltage-controlled oscillator (VCO) for 5.72GHz WiMAX applications. The fully integrated VCO is designed and simulated using 130-nm CMOS technology. Instead of using the conventional diode-based varactor in the tank design, high-performance body-grounded NMOS transistors are employed as effective varactors. A controlled self-biasing current source is implemented to avoid higher power supply sensitivity and higher up-conversion of flicker noise. The proposed VCO-measured results demonstrate a worst case phase noise of -132.68dBc/Hz at 1MHz frequency offset with an excellent figure of merit (FOM), which is -201.6dBc/Hz under a power consumption of 2.21mW. The VCO shows a tuning range of approximately 37.59%.