How to avoid loss of accuracy when using the Spectrum Analyzer block

When validating the output of a physical model using spectrum analyzer, the output has a small loss in accuracy based on the solver selected. How can I improve the accuracy of the spectrum analyzer block?

Answer 1

[MathWorks Support Team]

The issue you have noticed was caused due to the spectrum analyzer block. Specifically, the RBW setting within the spectrum analyzer block.

This setting is automatically selected based on the model but can be altered if required.

For example, when the RBW is set to '195.21' Hz it would only require 245888 Samples required per update but it would cause a slight loss in accuracy. If a smaller value is used, for example RBW = 20Hz, the frequency will get closer to to the expected value. However, doing this will result in higher Sample/update, which implies a slower update of the result.