Locking techniques for RF oscillators at 5-6 GHz frequency range

This work aims at analyzing three different techniques for synchronizing RF oscillators. These techniques are Injection Locking (ILO), Phase Locked Loop (PLL) and Injection Locked Phase Locked Loop (ILPLL). ILPLL, which is a combination of PLL and ILO, has superior noise performance -compared to all the rest- at medium frequency offsets and the same noise performance at low and high offsets. Furthermore, the ILPLL has better locking range and lower phase noise than the ILO for phase-shifts close to /spl plusmn/90/spl deg/. In this work we present two different approaches for the study of the performance of the ILPLL, which as we show, produce equivalent results concerning the noise. A common gate VCO was used and the injected signal was the same for comparison reasons.