Evaluation Of Bicorrelations For Transient Detection

Correlations and bicorrelations of a model 20 Hz finback whale signal and two actual data sinusoidal transient signals are examined to investigate the suitability of correlation and bicorrelation processors for the detection of oscillatory transients. The connections to moments of the distribution of ordinate values of the signals and the signal bispectrum are also discussed. We show that the bicorrelation processor is not a particularly good detector compared to the correlation in the simplest detection scheme for the whale signal (and likely not for other signals of small third moment) and that the bispectrum of narrowband transients is generally small except for transients at very low frequency.