Calibrated Target Strength Measurements for Multibeam Echosounder: Applications for Habitat Assessment

SEAPIX is a reversible Mills Cross multibeam echosounder composed of two arrays, each of them stabilizing beams with a MEMS sensor included in the Sonar Antenna Unit. This multi-beam SONAR provides metrological signals that can be derived to target strength (TS) and volume backscattering (SV) metrics on multiple swaths. Among other environmental variables, indicators like TS or SV are exploited for fish discrimination. Each detection is referenced in 3D in the water column and is automatically reported on a map built in real time including local bathymetry. According to hydrographic standards, SeapiX bathymetry is special order when coupled with external high quality motion reference unit. Additionally, SeapiX provide bottom hardness measurement based on backscattering strength (BS) allowing basic analysis on seabed habitats. Finally, SeapiX is a versatile echosounder able to address a wide range of application like fishery sciences, hydrographical survey or offshore windfarm monitoring.