A 157.8–166.3 GHz Fundamental Oscillator Achieving −181.9 dBc/Hz FoM in 65 nm CMOS

This letter presents a sub-terahertz fundamental oscillator using a magnetic tuning technique and drain-to-source transformer feedback to extend the tuning range and enhance the output power. Realized in a 65-nm CMOS process, the proposed prototype operates above
f
_max
/2 and achieves a frequency tuning range from 157.8 to 166.3 GHz with a phase noise of −105 dBc/Hz at 10-MHz offset, a dc-to-RF efficiency of 2.1%, and a power consumption of 5.6 mW, corresponding to an figure of merit (FoM) of −181.9 dBc/Hz.