%0 Journal Article
%T Sub-antenna processing for coherence loss in underwater direction-of-arrival estimation
%+ Département Signal et Communications (SC)
%+ Lab-STICC_ENSTAB_CID_TOMS
%+ Pôle STIC_AP
%+ DGA Tech.Navales
%A Lefort, Riwal
%A Emmetiere, Rémi
%A Bourmani, Sabrina
%A Real, Gaultier
%A Drémeau, Angélique
%< avec comité de lecture
%@ 0001-4966
%J Journal of the Acoustical Society of America
%I Acoustical Society of America
%V 142
%N 4
%P 2143-2154
%8 2017-09-01
%D 2017
%R 10.1121/1.5007727
%K Acoustic signal processing Acoustic waveguides Antennas Lenses Acoustical properties
%Z Engineering Sciences [physics]/Acoustics [physics.class-ph]Journal articles
%X This paper deals with the loss of coherence in underwater direction-of-arrival estimation. The coherence loss, which typically arises from dynamical ocean fluctuations and unknown environmental parameters, may take the form of a multiplicative colored random noise applied to the measured acoustic signal. This specific multiplicative noise needs to be addressed with methodological developments. This paper proposes a weighting process that locally mitigates the effects of the coherence loss. More specially, a set of coherent sub-antennas is designed from the so-called Mutual Coherence Function (MCF). The assessed source position results from the combination of each sub-antenna by using a mixed norm. Two experiments are considered in the paper: either a random noise is sampled to simulate the effect of random ocean fluctuations, or a synthetic acoustic waveguide is used in which the coherence loss is due to some multipath interferences. It is shown that the weighting process allows for a decrease in the estimation error in comparison to a Conventional Beamformer (CB).
%G English
%L hal-01653663
%U https://hal.science/hal-01653663
%~ UNIV-BREST
%~ INSTITUT-TELECOM
%~ ENSTA-BRETAGNE
%~ CNRS
%~ UNIV-UBS
%~ LMA_UPR7051
%~ ENSTA-BRETAGNE-STIC
%~ ENIB
%~ LAB-STICC
%~ IMTA_SC
%~ LAB-STICC_IMTA
%~ IMT-ATLANTIQUE
%~ INSTITUTS-TELECOM
%~ IMTA_MEE