Divide-by-Three Injection-Locked Frequency Divider Combined With Divide-by-Two Locking

A divide-by-3 direct-injection-locked frequency divider is demonstrated with an extra divide-by-2 operation by utilizing the two-fold frequency at the common-node between the drain-pumped injectors. The effective transconductance of the injectors is increased due to the existence of divide-by-two locking circuitry. The measured locking range is from 11.77 to 16.64 GHz (34.28%) with an output power of -7.25 dBm, as the core-circuit taking a power consumption of 4.2 mW from 1.2 V power supply.