A 1.2V low-power CMOS voltage-controlled oscillator (VCO) using current-reused configuration with balanced resistors for IEEE 802.16e

In this paper, a 1.2V low-power CMOS current-reused voltage-controlled oscillator (VCO) for IEEE 802.16e is presented. Two drain resistors are used to improve magnitude symmetry of output signals. The design is based on the TSMC 0.18μm mixed signal/RF process. The output frequencies range from 2.39GHz to 2.21GHz with the controlled voltage from 0V to 1.2V. The measured output power is -4.2dBm and phase-noise is -121dBc/Hz at 1-MHz offset frequency. The power consumption of the VCO with buffer included is only 3.96mW at 1.2V voltage supply.