ON SOURCE AND SCATTERER DETECTION IN THE UNDERWATER ACOUSTICAL CHANNEL

Short-scale sound field variations in waveguide impeded source and scatterer detection probability calculation in the presence of additive interference since the field variations are badly predictable for environmental parameters (sound speed profile, bottom parameters) known with true accuracy. The magnitude of deterministic component in the mixture of signal and interference can vary significantly when the source (the scatterer) is located in the minimum or in the maximum of the field structure. This difficulty can be avoided when the field structure versus range is assumed to be random process although the field structure in the regular waveguide is deterministic and it can be computed, for instance, using eigen mode decomposition. This approach was manifested in particularly in [1,2] for study of sound field intensity scintillations. The well known sound field representation (, ) p rz for the source of tonal signal of unit amplitude in the plane-layered waveguide is written as the sum of propagating modes: