Wide Tuning Range CMOS Millimeter-Wave VCO Using Resistors-Added MOSFET Varactor

Abstract

In this thesis, a new resistors-added MOSFET varactor which provides a wide tuning capacitive range and a CMOS millimeter-wave VCO for a wide tuning range with the varactor is presented. Large resistors connected to the source and bulk of a MOSFET varactor gives rise to lower minimum capacitance and equal maximum capacitance compared to a conventional MOSFET varactor. Thus, a total capacitive range of the proposed varactor is expanded as amount of 17%, allowing the VCO posses a frequency tuning range of 13.4% ranged from 29.3 to 33.5 GHz. The measured phase noise is -97.8 dBC/Hz at 1-MHz offset at the center frequency of 31 GHz. This VCO dissipates 12.5 mW from 1.8-V supply voltage and 7 mA, and is designed and implemented in a 0.18-μm standard CMOS process.