Localization error analysis of a fast broadband matched field method for a single hydrophone

We investigate the localization errors of a method which gives range and depth coordinates for a broadband sound source using a single hydrophone. It is based on the matching of theoretical multipath time-delays to those measured from the received signal. We focus on developing a fast method but still accurate for short ranges, thus allowing for real-time tracking of the source. We therefor investigate an analytical model for the time-delays based on straight line propagation but where the depth-varying sound velocity is accounted for. It is shown that this model provides much smaller localization errors compared to an isovelocity model, i.e. where a constant sound velocity is used.