Data/hora: 01/06/2024 10:15:31

Provedor de dados: | 5
País: | France
Título: | Swath bathymetry using phase difference: Theoretical analysis of acoustical measurement precision
Autores: | Lurton, Xavier.
Data: | 2000-07
Ano: | 2000
Palavras-chave: | Sonar signal processing; Sidescan sonar; Sea floor bathymetry; Multibeam echosounder; Interferometry; Bathymetry precision; Acoustic scattering.
Resumo: | The phase difference principle is widely applied nowadays to sonar systems used for sea floor bathymetry, The apparent angle of a target point is obtained from the phase difference measured between two close receiving arrays. Here we study the influence of the phase difference estimation errors caused by the physical structure of the backscattered signals. It is shown that, under certain current conditions, beyond the commonly considered effects of additive external noise and baseline decorrelation, the processing may be affected by the shifting footprint effect: this is due to the fact that the two interferometer receivers get simultaneous echo contributions coming from slightly shifted seabed parts, which results in a degradation of the signal coherence and, hence, of the phase difference measurement. This geometrical effect is described analytically and checked with numerical simulations, both for square- and sine-shaped signal envelopes. Its relative influence depends on the geometrical configuration and receiver spacing; it may be prevalent in practical cases associated with bathymetric sonars. The cases of square and smooth signal envelopes are both considered. The measurements close to nadir, which are known to be especially difficult with interferometry systems, are addressed in particular.
Tipo: | Text
Idioma: | Inglês

Identificador:

http://archimer.ifremer.fr/doc/2000/publication-710.pdf

DOI:10.1109/48.855385

http://archimer.ifremer.fr/doc/00000/710/

Editor: | IEEE
Formato: | application/pdf
Fonte: | IEEE Journal of Oceanic Engineering (0364-9059) (IEEE), 2000-07 , Vol. 25 , N. 3 , P. 351-363

Fonte:

2001 Acoustical Society of America

info:eu-repo/semantics/openAccess

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