How To Achieve Optimally Low Noise Floors In Phase Noise Testing Using External References

This application note focuses on the phase noise measurement of very low noise reference sources and explains why external references can be very useful to speed up measurement.

The efficient use of the PNT with crosscorrelator and external references is highlighted to benefit from faster measurement speed when measuring ultra-low SSB phase noise of DUTs. When using BNC's PNT signal source analyzer, one has the choice to use:

• standard internal references
• option LN: close to carrier ultra low noise internal references
• voltage tunable external references.