Perspective of Sentinel-1 for Maritime Surveillance Applications
Greidanus, Harm¹; Vachon, Paris^2
1European Commission - Joint Research Centre, ITALY; ²Defence R&D Canada - Ottawa, CANADA

The paper discusses the contribution that Sentinel-1 can make to maritime surveillance, i.e. finding and tracking ships on the sea. Maritime awareness is needed in the context of many issues, such as maritime safety, protection of fisheries, of the environment and of marine resources in general, irregular overseas immigration, smuggling, crime, piracy and further maritime security. People have been trying to use satellite SAR for these applications for many years, and the fundamental challenge specific for the maritime is always how to match the dynamic nature of the ship traffic with the inherent limitations of orbital SAR. A history of publications already exists discussing how satellite SAR can be used, and what is its (expected) performance. However, following a wider availability of systems (Envisat-ASAR, Radarsat-2, TerraSAR-X and Cosmo-Skymed), recent years have seen a significant increase in (semi-) operational use, leading to valuable practical feedback. Furthermore, other maritime surveillance technologies have also been evolving, such as UAS (Unmanned Airborne Systems), satellite AIS and improved data fusion functionalities, changing the context in which satellite SAR operates.

To better delineate the expected contribution of Sentinel-1 to maritime surveillance, the paper will compare Sentinel-1's relevant system parameters (resolution, swath, revisit frequency, response time, etc.) with the scenario requirements (target and area sizes of interest, required response time, other available surveillance means, etc.). It will do so for a few of the presently most relevant scenarios, related to irregular immigration, piracy, fisheries protection and polluter identification. Different geographical zones of interest will be taken into account - in particular in Europe, Canada and Africa. Sentinel-1's acquisition scheduling, ground segment capacity and data policy will have significant impacts, and their implications will in particular be considered. Use will be made of recent experiences from maritime surveillance projects for counter-piracy off East and West Africa, operational experiences around Canada, and of previous theoretical work on Sentinel-1 maritime applications potential that was more directly tied to minimum detectable ship size.