Passive Detection Method Based on Non-cooperative Underwater Acoustic Pulse Signal

Non-cooperative passive detection is a new type of underwater acoustic detection technology, which originated in the field of radar. It detects the target scattered echoes through active signals emitted by non-cooperative sources. Since this mode can perform high-gain detection of long-distance targets without transmitting a detection signal, it has great development prospects. In this paper, a target detection method based on non-cooperative pulse signal is proposed, and the non-cooperative transmitted signal is reconstructed by fractional Fourier transform (FRFT) as a matched filter template. Taking the emission sound source as the positioning assistant point, the position of the assistant point is determined by using the dual-array positioning technology, and the target is measured by calculating the relative positional relationship between the assistant point and the target. The simulation experiments show that the non-cooperative target positioning technology used in this paper has obvious advantages compared with the traditional dual-array passive positioning technology. The mean positioning error of this method for passive targets at a distance of 15km is less than 5%.