The Accuracy Limit of Area Correlation Guidance

One of the inherent advantages of area correlation guidance over object tracking guidance is greater guidance system flexibility. Another advantage is significantly improved system accuracy, especially if tracking is to be terminated well ahead of vehicle impact. The accuracy inherent in the area correlation process is the subject of this paper. It is unique because accuracy analysis is based upon the power spectral density function of the terrain/reference combination, rather than upon terrain autocorrelation function as are most other publications concerning this subject. For the purpose of this accuracy analysis, only error sources inherent to the correlation process are considered. The constituent error contributions are analyzed and combined and a correlation process error expression is derived. This is followed by a simplified parametric-numerical illustrative example.