A 21.7-to-41.7-GHz Injection-Locked LO Generation With a Narrowband Low-Frequency Input for Multiband 5G Communications

An injection-locked local oscillator (LO) generation targeting mm-wave multiband 5G communication is presented. With a band-selective injection-locked frequency multiplier (ILFM), the LO generation can operate from 21.7 to 41.7 GHz with a narrowband 6.2-to-8.0-GHz input source. An injection-locked amplifier (IL-amp) is cascaded for harmonic rejection. Fabricated in a 65-nm CMOS process, the proposed LO generation consumes 74.4-mW power with 5.0-dBm output power. A 25.3% input bandwidth is extended to a 63.1% output operating bandwidth with no further phase noise degradation. A -105.6-dBc/Hz phase noise at 1-MHz offset is measured at 24 GHz with a -42.7-dBc integrated phase noise. The LO generation rejects the unwanted harmonics to more than 30.0 dB and occupies 0.52 mm
²
.