Getting Its Measure: Oscillator Phase Noise Measurement Techniques and Limitations

Accurate measurement of phase noise is one of the most difficult measurements in all of electrical engineering. The biggest challenge is the huge dynamic range required in most phase noise measurements. There are several methods to measure phase noise, and the right one must be chosen to make the necessary measurements. To make a proper selection from the various methods, it is necessary to know and appreciate the weaknesses and strengths of each of the different techniques because none of these methods is perfect for every situation. This article focuses on key phase noise measurement techniques for oscillators and reviews their advantages and disadvantages.