Reverberation tail in power delay profiles: Effects and modeling

Long reverberation tails are not uncommon in underwater acoustic channel impulse responses. We show a few examples of underwater channels which all exhibit this feature, and consider their properties in some more detail. The effect of insufficient modeling of the reverberant tail is then demonstrated. Approaches for model based simulation are discussed briefly, and a few attempts of such modeling are tried. However, precise modeling requires sophisticated models, as well as detailed environmental knowledge, and at the moment our capability for model based simulation is limited.