Modeling of echoes from elastic spherical and cylindrical shells in a convergence zone

Abstract

The monostatic echoes from an arbitrary incident signal in a deep ocean environment are computed for aluminum, steel, and plastic spherical and cylindrical shells. The target frequency response is calculated using thin shell theory. The medium response is obtained using the frequency-based generic sonar model (GSM). The combination of the target and medium transfer functions gives the full frequency response for the target-medium system. The product of the total transfer function with the frequency spectrum of the incident signal yields the quantity whose inverse FFT is the time series or echo. This return signal incorporates the effects of both the medium and target on the incident signal. [Work supported by ONT Code 231.]