A $V$ -Band Wide Locking Range Divide-by-4 Injection-Locked Frequency Divider

A novel V-band divide-by-4 injection-locked frequency divider (ILFD) topology involving an injection loop and an output loop coupled by a two-port LC-tank has been proposed. With the specially designed LC-tank, the third-order harmonic component can be enhanced in the injection loop, so that the mixing using the second-order nonlinearity can be used to realize divide-by-4, and thus, the locking range can be improved. Simultaneously, the output loop excites the oscillation at the fundamental frequency and suppresses the third-order harmonic components, facilitating a stable oscillation at the fundamental frequency and avoiding the effects of third-order harmonic on the following stages. Fabricated in a 65-nm CMOS technology, the proposed ILFD demonstrates a wide locking range of 60.2-69.9 GHz (14.9%) while consumes 4.8 mW from a 0.75-V supply.