The State of the Art in CMOS VCOs: Mm-Wave VCOs in Advanced CMOS Technology Nodes

There is a growing interest in the realization of highly integrated radar transceivers operating at millimeter-wave (mm-wave) frequencies. In this case, CMOS is the natural technology choice. Modern nanoscale CMOS technologies offer excellent transistor performance with transit frequencies (f_T) and maximum oscillation frequencies (f_max) exceeding several hundreds of gigahertz. This enables the realization of highly integrated, digitally intensive transceiver systems on chip for mmwave applications, such as 77-GHz automotive radar [1] or wireless data communication systems [2]. Several advanced nanoscale CMOS nodes even surpass the f_T and f_max values achieved by silicon germanium (SiGe) heterojunction bipolar transistor technologies [3].