ABSTRACT
The array of towed line array sonar is usually a single line array, which is working in a passive way. It could acquire bearing of target, but not distance. Besides, the array is a line array which is made up of many non-directional hydrophones, so if there is a target at the port-side/starboard-side, there must be a mirror fountainhead at the starboard-side/port-side with the same relative bearing due to the directivity of cylindrical symmetry. The target’s bearing and the mirror fountainhead’ bearing could not be discriminated, that is the problem of port-side/starboard-side discrimination [1].
