Underwater positioning system and method

Abstract

An underwater positioning system for accurate underwater positioning. At least one among at least one acoustic transmitter and at least one hydrophone is provided at known coordinates and which positions an unknown point having unknown coordinates at which another acoustic transmitter or hydrophone is provided, includes a time window that stores in advance, when the unknown point is set in a plurality of regions set by dividing an underwater positioning range, a time window for a sound wave emitted from the acoustic transmitter to reach the hydrophone for each of the regions, and a coordinate estimation and specification unit that calculates for each of the regions a time window-applied impulse response as an inner product of the time window and an impulse response of a sound wave propagation path from the acoustic transmitter to the hydrophone and estimates that the unknown point is located in the region where the energy of the time window-applied impulse response is maximized.