CMOS Injection-Locked Frequency Quadrupler/Quintupler

This paper designs a C-band single-stage $LC$ -tank injection locked frequency quintupler (ILFQ) fabricated in $0.18~\mu \text{m}$ CMOS process. The differential input/output ILFQ circuit is made of a first-harmonic injection-locked frequency oscillator (ILO) and a frequency quadrupler/quintupler. The free-running oscillation frequency of the ILFQ is around 7.6 GHz. At the dc power consumption of 9.9 mW and at the incident power of 0 dBm, the input locking range is from the incident frequency 1.456 GHz to 1.644 GHz to provide an output signal source from the frequency 7.28 GHz to 8.22 GHz. The whole chip occupies a die area of $1.114\times 1.060$ mm². The designed circuit is also used as a new X-band single-stage LC-tank injection locked frequency quadrupler, which shows measured $\times 4$ output locking range from 7.82 GHz to 8.6 GHz.