FN Archimer Export Format
PT J
TI Swath bathymetry using phase difference: Theoretical analysis of acoustical measurement precision
BT 
AF LURTON, Xavier
AS 1:;
FF 1:PDG-TMSI-AS;
C1 IFREMER, TMSI AS, F-29280 Plouzane, France.
C2 IFREMER, FRANCE
SI BREST
SE PDG-TMSI-AS
IN WOS Ifremer jusqu'en 2018
IF 0.5
TC 48
UR https://archimer.ifremer.fr/doc/2000/publication-710.pdf
LA English
DT Article
DE ;Sonar signal processing;Sidescan sonar;Sea floor bathymetry;Multibeam echosounder;Interferometry;Bathymetry precision;Acoustic scattering
AB 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.
PY 2000
PD JUN
SO IEEE Journal of Oceanic Engineering
SN 0364-9059
PU IEEE
VL 25
IS 3
UT 000088552500008
BP 351
EP 363
DI 10.1109/48.855385
ID 710
ER

EF