Comparing Waveforms

[Amifriend]

Hello everyone! I'm a complete beginner with LabVIEW and would like to ask the following question. For testing pieces, we apply a frequency sweep signal ranging from 330 kHz to approximately 360 kHz and observe the resulting signal. We observe a resonance curve, and if it's deformed (for example, on the oscilloscope, we see not just a single peak but several), it indicates an issue.

I have an NI USB 6351 card. Are there ways to compare these two signals in LabVIEW? For instance, can I take the signal from a conforming piece as a reference and compare it each time with the signal from the piece to be tested? Or are there other comparison methods in LabVIEW, whether based on signal shape, frequency content, or the similarity of the two signals?

[ZYOng]

There are some VIs in Signal Processing >> Waveform Measurements palette that you can use to extract the characteristics of a waveform.

[altenbach]

For analysis purpose, it is completely irrelevant where the data comes from. It's all pure math.

As a first step you need to define what is a difference and what is not. For example should they be normalized for area or amplitude before comparing? Can you define a valid envelope where the signal needs to be (e.g. reference data +/-10%). Are there other parameters that need to match (e.g. width at half max), Does the curve follow a simple mathematical model that can be fit? etc.

Maybe as a first step attach a small VI containing the reference data and some good and bad data.