Direct Geometric Positioning for the Three-Dimensional Imaging Microware Altimeter

The three-dimensional imaging microware altimeter is a new type of altimeter, which combines with traditional altimeter height tracking measurement technology, SAR synthetic aperture technology and SAR interference measurement technology. The direct geolocation technology is a little different from traditional SAR geolocation technology. In this paper, a geometric positioning algorithm based on the Range-Doppler equations has been proposed for the three-dimensional imaging microware altimeter, and the main positioning error sources, including elevation error and atmosphere transmission delay, are analyzed and corrected. The positioning precision is validated by corner reflectors. The result shows that the direct positioning accuracy improved by 3 pixels.