Abstract: According to the shallow-water combat applications of submarine-launched torpedo, three typical hydrological conditions were used to calculate the detecting range and direction-finding error of torpedo flank array sonar by utilizing the mid-frequency active sonar pulse signals. The results show that, in the anti-ship warfare, the flank array sonar of submarine-launched torpedo can detect a surface target at long distance by intercepting the active pulse signals from the surface target, and the flank array sonar can use for homing due to its high direction-finding accuracy when a target is detected.

Key words: information processing, torpedo, flank array sonar, passive detection, beamforming