A 70 and 210 GHz LO generator in 65nm CMOS

A CMOS LO-Generator operating at 70GHz and 210GHz by the use of a frequency tripling technique is presented. A cross-coupled NMOS VCO is used together with a single-balanced mixer to achieve low phase-noise. The chip measures a single-ended output power of -15dBm in the 70GHz band, with 6.54% tuning range, from a 1.2V supply while consuming 7.2mW. A phase-noise of -113.2dBc/Hz is measured at 10MHz frequency offset from a carrier frequency of 73.8GHz. This yields a phase noise figure of merit, FOM, of 181.8dB, and with the tuning range taken into account, a FOM_T of 178dB. By using this technique neither FOM nor FOM_T are degraded in the 210GHz band since both power consumption and tuning range are maintained.