Method for estimating target range error and sonar system thereof

PURPOSE: A method for estimating a target range error and a sonar system thereof is provided to accurately a target distance and a distance error by estimating a transfer path through real underwater conditions. CONSTITUTION: A method for estimating a target range error and a sonar system thereof are comprised of steps: setting a target range to estimate the distance error of the target; inputting the marine conditions of a target area; estimating a detection range and an approach time and water pressure in a multiple path, distance, and water depth; and filtering the sound paths of the multiple path to extract a sound path in which a sound pressure is strongest or through which a sound is approached to the target area first.