2011 Volume 131 Issue 3 Pages 507-513
This paper describes a new techniques of reducing phase noise in oscillator circuits. Our method uses an external crystal resonant circuit that acts as a frequency reference and is based on correlation with negative feedback control. We present the circuit configuration and the transfer function used in this method, as well as measured single sideband (SSB) phase noise characteristics. Our experiments show that phase noise can be decreased as it is a theoretical value when using LC oscillator. Furthermore, we examine application for voltage controlled crystal oscillator (VCXO). As a results, we can improve that the phase noise characteristics more than that of original VCXO without spoiling frequency tuning range of VCXO.
The transactions of the Institute of Electrical Engineers of Japan.C
The Journal of the Institute of Electrical Engineers of Japan