In this study, the physical relationship between the shape parameter v of the K-distribution and the spatial correlation of a sea clutter signal received with a radar is demonstrated through simulation results. The spikiness of the sea clutter is well modeled by the shape parameter v of the K-distribution. According to a well-known empirical formula, the shape parameter v changes with the radar resolution based on a constant power-law relation. However, as with most empirical findings, this finding is valid only for the environmental conditions under which the formula was developed. In other words, the existing power-law models for the shape parameter of the K-distribution for sea clutter do not consider the relative ratio of the cross-range resolution Rc to the spatial decorrelation length Rdec of the sea surface. Our study investigates this relation using statistical simulations based on the principle of superposition for backscattered signals that represent sea clutter within a resolved area on the sea surface. This study shows that the constant factor α in the power-law relation must be modified to a function of the ratio Rc/Rdec. The findings of this study will be useful for the evaluation of detection performance in designing radar systems operating in the maritime environment.
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