Synchronous Averaging
SAMURAI™-Option
Rotational-speed-synchronous averaging of complex FFT blocks
Overview
Application
This option can be used to determine the vibration or sound spectrum of a rotating parts with high levels of interference. The method is suitable if vibrations that are not originating from the main rotation event are superimposed on the signal of interest and thereby interfere with the evaluation of essential spectral properties associated with the rotation analysis.
Description
The basic principle of the software is to average many complex FFT spectra that are calculated synchronously with the rotation. Spectral components that do not originate from the rotation are statistically suppressed in the averaging result and thus the signal-to-noise ratio can be drastically improved.
Figure 1:
Rotation-synchronous FFT spectrum. Measurement on a fan with 39 blades. Averaging result of the FFT analysis after 10 seconds.
Figure 2:
The black graph represents the averaging result of the rotation-synchronized FFT analysis after 13 seconds. The blue graph shows the spectrum of the continuously averaged FFT analysis. The improved signal-to-noise ratio can be clearly seen.
Features
| Signals | typically used with microphone or structure-borne signals |
| Scope |
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Requirements
This software option requires a valid SAMURAI™ base license.