Application of Statistical Estimation Techniques to Terrain Modeling

摘要

This thesis researches methods of generating accurate and realistic polygonalterrain models by reducing gridded sampled terrain elevation data such as DMA DTED. The terrain models generated should be applicable for use in flight simulators and other systems. Existing methods of terrain modeling are discussed, and limitations of these systems are presented. The geostatistical estimation technique known as kriging is presented as a method estimating terrain elevations at locations not provided in DMA DTED or other gridded terrain elevation data. Kriging is an optimal interpolation method based on statistical analysis of the data. It also provides a measure of accuracy, the error variance, that allows some control over the accuracy of the resulting terrain model. This estimation method is employed in a terrain modeling system that builds polygonal terrain models at any resolution. This system is described in this thesis, and the results of terrain modeled both by filtering the DMA DTED and by estimating elevations with kriging are presented. The technique as implemented is computationally very expensive and has therefore limited the results of this thesis effort. Also, terrain models that could be produced appeared smoother than their filtered counterparts. However, kriging still shows promise as a method of estimating terrain elevations for terrain models.