Advances in Measurement and Modelling of Bistatic Sea Clutter

An analysis is presented of the results from recent trials to gather 2.4 GHz bistatic sea clutter, and in particular, of fitting the compound K distribution model both to bistatic clutter data and to simultaneously-acquired monostatic clutter data. It is found that the K distribution provides a good fit to the bistatic data, but that the bistatic clutter is significantly less ‘spiky’ than that of the equivalent monostatic distribution – i.e. that the tail of the distribution is shorter. This result is important, because it suggests that a bistatic geometry will give improved detection performance of weak targets against a clutter background compared to the conventional monostatic geometry. These results lead to the concept of ‘clutter diversity’, in which in a multistatic or netted sensor, advantage is taken of a knowledge of the variation of the properties of clutter in this way, as an additional degree of freedom that can be exploited to adaptively optimise the overall radar system performance.