1. A sensor system for relating disparate data models of a physical object to derive a first-range data model at a first-range distance, d, from a second-range data model at a second-range distance, d.sub.0, comprising: a sensor for transmitting signal correspond to the physical object; means for obtaining said second-range distance from said signals transmitted from said sensor corresponding to said physical object; means for smoothing the second-range data model by a function of d and d.sub.0 ; and means for undersampling said smoothed second-range data model to obtain said first-range data model.