Computing A Bomb’s Location

Sound travels in water at a speed of almost 2 meters per millisecond (1/1000th of a second). To achieve reasonable accuracy in computing a location, the signal from the hydrophone must therefore be time-stamped with a very accurate clock. This became possible with the advent of GPS disciplined clocks in the past two decades.

Using a cloud server, reports from three or more of these time-accurate sensors can be compared using time-of-arrival calculations to compute the blast location.

The word that most people know is triangulation, however the correct and generalized term is multilateration.

Additionally, if the sensor uses more than one hydrophone, an angle-of-arrival calculation can be computed to improve the location accuracy.