A 35.2-51.4GHz Frequency-Tracking Injection-Locked Frequency Tripler Achieving >28.5dBc Harmonic Rejection Ratios, -7.3dBm Output Power, and 4.3dB Output Power Variation

This paper presents a novel-frequency-tracking injection-locked frequency tripler (ILFT) featuring wide locking range (LR), high harmonic rejection ratios (HRRs), high output magnitude, and low output magnitude variations. The proposed ILFT utilizes a single-ended injection combined with an amplitude detection method to enhance frequency tracking bandwidth. A dual-core topology is also implemented to improve even harmonic rejection and to provide differential output signals. Fabricated in a 28-nm CMOS process, the ILFT measures an LR of 37.5% from 35.2 to 51.4GHz while achieving an output magnitude of -1.6dBV with magnitude variation of 2.9dB and HRR1 and HRR2 of 36.4–46.7 dBc and 40.8–50.3 dBc, respectively. The total power consumption of the dual-core frequency-tracking ILFT is 11.6mW.