HP Data Explorer 4 Calculator, 6.4 Using the Signal-to-NoiseRatio, Description, Calculating signal-to-noiseratio

Using the Signal-to-Noise Ratio Calculator

6.4 Using the Signal-to-Noise Ratio	6
Calculator

Description A signal-to-noise ratio is typically used to describe how well a peak of interest in a spectrum or chromatogram is distinguished from background noise.

The Data Explorer software provides two signal-to-noise ratio methods that calculate signal-to-RMS noise (electronic and chemical):

•Auto— You specify the peak for calculation and the software automatically calculates the average noise across the spectrum.

Calculating signal-to-noise ratio

•Manual— You specify the peak and the baseline region for calculation. For accurate results, this method requires a flat (non-rising) baseline that does not include peaks. The manual method is useful when evaluating a narrow region around a peak to determine the relative significance of a peak.

To calculate a signal-to-noise ratio:

1.Click the Spectrum window to activate it.

2.From the Tools menu, select S/N Calculator.

The Signal-to-Noise Calculator dialog box (Figure 6-14)is displayed.

Figure 6-14 Signal-to-Noise Dialog Box

Data Explorer™ Software User’s Guide 6-23