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Characterisation of Location Discrepancies between ENVISAT/ERS Ship Detection Reports and AIS Records During the MARISS Phase 2 Trials in France

Jean-Yves Le Bras(1), Olivier GERMAIN(1) and Guillaume HAJDUCH(2)

(1) CLS, 8-10 rue Hermès, Parc Technologique du Canal, 31520 Ramonville, France
(2) BOOST Technologies, 115, rue Claude CHAPPE, Technopole Brest Iroise, 29280 PLOUZANE, France


During the first phase of the MARISS project (1) CLS has set-up a near real time vessel monitoring chain based on its operational system for surveillance of illegal fishing in the Indian Ocean and integrating the SARTool© software, developed by BOOST Technologies.

Trials performed in the English Channel in 2006 were presented in ENVISAT Symposium 2007 showing several coupling examples between ENVISAT IS6 data and VMS systems, a comparison by the user to VTMS data, and also raising several perspectives of improvement (2). This paper will focus on the second phase of the project.

As for the first phase, ENVISAT SAR scenes (narrow swath, IS6 submode, HH polarization) were acquired, processed at Level 1b (ASA_IMP products) and provided by Kongsberg Satellite Services (KSAT), and completed by ERS PRI images acquired by ESA stations through Cat-1 mechanism, ENVISAT WS ship detection reports through ESA GSE MARCOAST, and metocean data acquired by CLS.

Automatic Identification System (AIS) data were used in addition to VMS and VTMS for ground truth identification of vessels.

This paper will present the main results of these trials:

• an assessment of new chain capabilities implemented after the first phase, such as the azimuth ambiguity removal function in the new version of SARTool©

• the use of GIS to reduce false alarms and assess image geolocation.

• the potential interest of combining ERS and ENVISAT data

• a characterisation of differences between locations reported by satellite radar and automatic identification systems.


(1) MARItime Security Services , ESA GSE project (2) “Ship Detection Trials With Envisat ASAR In The English Channel: Coupling Tests With VMS and VTMS”


Workshop presentation

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry