Multi-target tracking in the littoral environment

Existing state estimation algorithms for sea surface targets allow motion in three spatial directions. The approach described herein exploits directly ail available information, with surface ships constrained to the geoid - producing a model as close to reality as any representation humanly achievable. Not only is Earth curvature taken into account from the outset, but Earth oblateness and the geoid/ellipsoid height separation (taken into account by lookup table) are sewed into the estimator algorithm, in the same form used for GPS data. These effects are included everywhere applicable, not just as an external correction or an afterthought. To enhance computational reliability still further, an appropriately stable (e.g., factorized) algorithmic approach is unhesitatingly adopted. Factorization provides another side benefit of efficiency which, when added to the savings inherent with fewer states,(1) produces an almost irresistible incentive to pursue this opportunity to reap full benefit from tracker input data received.