Spatial Registration of TIROS-N Weather Satellite Data.

摘要

The purpose of this study was to develop an algorithm to perform spatial registration of (assign geographic coordinates to) TIROS-N weather satellite data using a personal computer. Specific objectives were 1) to gather currently available information into a unified and understandable form, 2) to develop the background and related theory necessary for the registration of both High Resolution Picture Transmission (HRPT) and Automatic Picture Transmission (APT) data, and 3) to present a specific registration algorithm for TIROS-N weather satellite data. The approach chosen is to use a general elliptical orbit model in conjunction with accurate satellite element sets (orbital parameters) to calculate accurate satellite positions at a given time. Knowing the earth movement and sensor operation as functions of time, the geographic locations of each pixel (picture element) are determined through geometric relations. The algorithm presented converts pixel coordinates to, geographic coordinates (direct referencing) and vice versa (inverse referencing). These algorithms assume an elliptical orbit (with perturbations) and an oblate spheroid earth. The most critical factor is found to be timing. A timing correction method is outlined to visually improve the image registration. (aw)