THE EFFECT OF SEA STATE ON SHIP WAKE DETECTABILITY IN SIMULATED SAR IMAGERY

Ship wake detection methods are mostly based on analyzing real SAR images of the sea surface. This is due to SAR imaging having achieved considerable maturity and becoming effective for their visualization, in particular through Bragg resonance scattering. However, in different environmental conditions, it is often difficult, sometimes impossible, to consider all possible factors that can dramatically change ship wake visualization. In this paper, an analysis of one important sea state factor, namely the fetch length, both for airborne and satellite SAR platforms is investigated and its contribution to the visualization of ship wakes in simulated SAR images is quantified. We study the effect of fetch in terms of wake detectability using a state-of-the-art method. The sea surface modelling is performed using the Joint North Sea Wave Project (JONSWAP) spectrum, whilst for Kelvin wake modelling the Michell theory is employed. The simulation results performed help clarify the influence of the sea state on ship wake visualization in SAR imagery.