A low phase noise 52-GHz push-push VCO in 0.18-/spl mu/m bulk CMOS technologies

A V-band fully integrated complementary push-push VCO is first presented in 0.18- /spl mu/m bulk CMOS technologies. Thin-film microstrip (TFMS) lines are utilized in the circuit to reduce the conductive substrate effect. In order to lower the phase noise, complementary cross-coupled pairs are used to generate negative conductance. The measured phase noise at 1-MHz offset is about -97 dBc/Hz at 52.6 GHz and is -104 dBc/Hz at 26.3 GHz. To the authors' best knowledge, this complementary CMOS VCO achieves the lowest phase noise in comparison with other VCOs using standard bulk CMOS processes in V-band.