Zero-crossing Detection for Underwater Moving Sound Sources

Zero-crossing detector is capable of predicting the shape changes of power spectrum so as to find the newly emerged moving sound sources in ambient noise. The performance of zero-crossing detector in terms of receiver operating characteristics (ROC) was derived based on the Neyman-Pearson criterion, and the relationship between optimal performance and pre-filtering frequency band was analyzed. The performance was also compared with the ROC of energy detector and power spectrum detector. Theoretical analysis and simulations on data measured at sea show that zero-crossing detector has not only low average energy cost, but also has robust performance in non-Gaussian noise.