ASA 125th Meeting Ottawa 1993 May

2aUW1. Preliminary bistatic and monostatic scattering results from a steep basin feature in the Tyrrhenian Sea.

J. R. Preston

SACLANT Undersea Res. Ctr. SACLANTCEN), CMR 426, APO, AE 09613

A feature scattering experiment was conducted by SACLANTCEN off the island of Palmarola in the Tyrrhenian Sea in March 1991. Estimates of this feature scattering are presented as a function of range, source type, and source depth. Area water depths ranged from 200 to greater than 3800 m. The receivers were a horizontal array of 64 elements spaced at 0.5, 1, and 2 m and a vertical array with 32 elements and the same spacings. Source depths varied from 90 to 1800 m and receiver depths ranged from 90 to 150 m. Depth charges were used as sources, as were low-frequency cw pulses and linear FM pulses of various pulse durations and bandwidths. Basin wide received reverberation levels and scattering strength values are also presented as functions of the estimated scatterer position on area bathymetry maps. Comparisons of shot and pulse data reverberation levels are presented. Estimates of monostatic bottom scattering strengths versus grazing angle are given using generic sonar model (GSM), PAREQ, and KRAKEN to interpret the data. Finally, comparisons of measured reverberation and modeled reverberation are presented.