Accession Number : ADA180587

Title :   Logarithmic Least Mean Square Sound-Field Estimation,

Corporate Author : SACLANT ASW RESEARCH CENTRE LA SPEZIA (ITALY)

Personal Author(s) : Zimmer,Walter M.

Report Date : MAR 1987

Pagination or Media Count : 32

Abstract : The report deals with narrowband beamforming techniques for passive sonar applications. In particular, the least mean square parameter-estimation technique is used to determine the spatial sound field power density. To find the optimal solution the steepest descent iteration has been selected in order to avoid computation-intensive matrix calculations. Comparisons have been between the steepest descent and the so-called WB iteration, a technique which was developed some years ago at SACLANTCEN by R. Wagstaff and J. L. Berrou. The results of these two iteration procedures have been compared against the conventional beamformer using perfectly known data, simulated random data and real data. Also, a statistical performance analysis has been carried out to provide numerical evidence of the probability of detection and resolution, and of the accuracy of bearing estimation. In this context the two sound-field estimation techniques have been compared not only with the conventional beamformer but also with the Capon adaptive beamformer and the MUSIC orthgonal beamformer.

Descriptors :   *PASSIVE SONAR, *BEAM FORMING, *ACOUSTIC FIELDS, ACCURACY, BEARING(DIRECTION), ESTIMATES, PERFORMANCE TESTS, STATISTICAL ANALYSIS, ITERATIONS, STEEPEST DESCENT METHOD, ADAPTIVE SYSTEMS, NARROWBAND, OPTIMIZATION, SOLUTIONS(GENERAL), SIMULATION, LEAST SQUARES METHOD, CROSS CORRELATION

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE