Automated Iceberg Detection Using High-Resolution X-Band SAR Images

Abstract

. In northern latitudes, icebergs frequently cross shipping routes and impair marine traffic. To improve ship routing, we explore the capabilities of an algorithm that detects and charts icebergs from images provided by the German radar satellite TerraSAR-X. TerraSAR-X is in a near-polar orbit, equipped with an active X-Band radar antenna and, thus, allows monitoring the ocean and frozen waters regardless of cloud cover and darkness. The algorithm we apply is based on the iterative censoring constant false alarm rate (IC-CFAR) detector, which has proven its usefulness for terrestrial target detection already. Unlike the standard approach, we not only estimate statistical properties of open water intensities expressed by a probability density function, but also search for recurring patterns (i.e., waves). This allows discriminating icebergs from most false alarms that arise from rough sea and strong winds. Experiments carried out with a series of HH-polarized TerraSAR-X Stripmap images acquired between 2012 and 2015 confirm that, due to consideration of wave pattern during image processing, the false alarm rate is reduced by a factor of 3.