Radar detection performance limitations in sea clutter for conventional noncoherent integration

Sea clutter echoes are well described using the spatial variation model. In this mode, the local temporal fluctuation within each area resolvable by the radar has a local mean that varies independently across resolvable areas. A much larger global area, having nearly the same grazing angle, defines the region in which the local mean varies spatially. This spatial variation model is used to determine radar detection performance in sea clutter of conventional noncoherent integration. The performance suffers significantly because of the additional fluctuation caused by the spatial variation. The degradation can be significant-as much as 20 dB or more over the homogeneous clutter case. The reduced performance is explained by the lack of smoothing the spatial variation. A remedy is offered based upon long-term integration over many resolvable areas as the target moves radially. The resultant smoothing, before presentation to a detection threshold, reduces the effect of the spatial variation.