Transiting ship's slant range estimation using single hydrophone in shallow waters

Passive source localization using single hydrophone has received considerable attention in the last decade particularly in marine biological studies. If proven successful, it should find tremendous applications, both in military and civilian. Underwater vehicles such as gliders, AUVs, ROVs, torpedoes, mines, etc. seldom have more than one sensor fitted on them for carrying out reconnaissance/ threat neutralization operations. Therefore, this paper investigates the usage of a method based on multipath time delays to estimate the slant range between the source and receiver. Time delays estimated theoretically were used to establish the usefulness/ limitations of this method. Surface ship's radiated noise signature was subjected to cepstral analysis to estimate time delays between the direct path and the surface reflected path. The time delays thus obtained were used for estimating the slant range between the source and receiver. The comparison between the measured and the estimated time delays was found to be satisfactory.