I added this VCO to @User’s Insipiration document. It uses an octagonal inductor: https://www.researchgate.net/profile/Bodhisatwa_Sadhu/publication/224601165_A_CMOS_33-84_GHz_wide_tuning_range_low_phase_noise_LC_VCO/links/55d4a05908ae1e6516636a9f.pdf