How to improve measurement stability with RMS X-Corr on the FSWX

When using the RMS X-Corr detector, the input signal is split after the attenuator. Then both signals use identical signal paths. The RMS X-Corr detector correlates the two signals, reducing noise from components after the splitter. Enable the RMS X-Corr detector in the trace settings. Compare the trace results for a common RMS detector and an RMS X-Corr detector. The X core factor defines how many samples are cross-correlated for each trace point. The ideal X-Corr factor is a trade of between sweep time and stability. With a factor of 20, The sweep time is still short, but the signal is unstable. Use markers to calculate the improvement in the RMS X-Corr trace. The trace improves by about 7 to 8 dB. Now increase the X-Corr factor to 10.000 Freeze the trace for factor 20 for comparison. The factor 10.000 (green) trace is much more stable than the factor 20 (blue) trace, but the sweep time is now 20 milliseconds. Try an X-Corr factor of 1000. Select the value in the application info panel. The sweep time is down to two milliseconds. A good compromise between speed and stability.