ARTICLES

Theory and Practical Considerations for Measuring Phase Noise Better Than –165 dBc/Hz: Part II

In part one of this article,1 the fundamental concepts of phase noise and phase noise measurements using direct spectrum analysis, instrument limitations, common sources of error and possible ways to minimize measurement errors were reviewed. In part t...
As discussed in part one of this article, the measurement of very good VCOs at large frequency offsets is limited by the spectrum analyzer’s dynamic range. This limitation can be overcome by using carrier filtering and selective amplification of noise at the offset frequency of interest. The bandpass filter...
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Theory and Practical Considerations for Measuring Phase Noise Better Than –165 dBc/Hz: Part I

Phase noise requirements have a major influence on the design of a communication system because they impact the local oscillator design and hence the cost of the radio. Since the number of wireless subscribers and thus, RF interference, continues to in...
Phase noise is a frequency domain measure of the short-term stability of an oscillator. It is measured and specified as noise power, relative to carrier power, in a one Hz bandwidth at a given frequency offset. Typically, for a communication system oscillator, the phase noise requirement is specified for...
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