A 24GHz low phase noise feedback CMOS LC-VCO
This paper proposes an effective method to improve phase noise in voltage controlled oscillator (VCO), which is realized with 90nm RF CMOS technology. A current source is used in this design to control the VCO power consumption, while the filtering technique is incorporated to reduce VCO phase noise, and a feedback loop from output to input is also adopted to further improve the phase noise performance. A •100.85 — •104.7dBc/Hz phase noise is achieved at 1MHz offset, and the frequency tuning range(FTR) spans from 24.7GHz to 28.8GHz, with a total power consumption of 5.5mW from 1.2V supply.