A D-band wide tuning range Class-F VCO using novel inductor-slot fusion transformer feedback

This paper presents a D-band Class-F harmonic voltage controlled oscillator (H-VCO) with a novel inductor-slot fusion tank, where the fundamental 35GHz signal and a considerably strong third harmonic at 105GHz are simultaneously excited. The desired 140GHz signal as forth order harmonic is self-mixed by an inherent up-mixer nearby tank and buffered to output through a two stage D-band buffer. A prototype is implemented and post-simulated upon commercial 65nm CMOS technology. EM simulation exhibits satisfying results with a tunning range of 32%, correspondingly 119-165GHz, within which the PN performance at 140GHz achieves -94.7dBc with 1MHz offset. The complete frequency generator draws 100mA current under 1V supply with a peak output power of -4 .6dBm. The figure-of-merit (FoM) remains between 176.4 and 178.2 dBc/Hz.