I. Introduction
Millimetre-Wave (mm-Wave) communication systems have attracted extensive attention due to the wide bandwidth to support high data rates. Down-conversion mixer is one of the key components of mm-Wave receivers for communication quality. CMOS down-conversion mixers often need a large local oscillation (LO) swing to achieve good performances. However, it is power hungry to produce a large LO at high frequencies. Hence, a down-conversion mixer working at low LO swing, while maintaining good performance in gain, linearity and noise figure (NF), is desired to save power consumption and alleviate LO driver design complexity.