The Detection and Tracking of Weak Frequency Line Based on Double-detection Algorithm

The paper aims to deal with the problem of automatic detection of narrow-band signals which is encountered in a passive sonar system. The double-detection algorithm at low signal-to-noise ratio is put forward on a basis of double-thresholds detection, and realizes the intelligence methods of frequency line detection and tracking. It makes frequency line detection and tracking more intelligent. The results of experimental data processing reveal that this method can increase the possibility of weak frequency line detection and tracking, and decrease the false alarm rate.