Detecting a Signal with Background Noise
Correlation can mathematically identifiy the similarity between different signals. This can be used to identify a known signal immersed in a background of noise. In this Demonstration, you can add white noise to a known signal. The maximum value of the convolution result indicates where the noisy data is most similar to the test signal. As noise is added, local maxima become larger and it becomes more difficult to identify the test signal with reasonable confidence.