Oscillators are important elements of RF and microwave communications systems. The increased use of the electromagnetic spectrum requires the use of better and cleaner oscillators. Local oscillators in RF to IF converters play a big role in the overall performance of the receiver systems because phase noise in the local oscillator can drastically reduce the signal to noise ratio at the output of the receiver, especially if the converter is at the front end. Phase noise is the parameter used to describe oscillator stability. The analysis and basic measurement techniques of phase noise are performed in this report.
This research report starts with a description of the ideal oscillator output in both time and frequency domains. Phase noise is then described in the time, frequency, and spectral density domains. The £(f) definition of phase noise is also included, and an example showing the measurement of phase noise.
Finally, an introduction to three different measurement techniques is given