Height corrected location algorithm analysis for emitter on Earth

When three satellites for passive location are used, if the height of terrain where the target locate changes greatly and the height is assumed constant the height error will be increased. So the Least-square estimation method is presented, at the same time in the process of algorithm iteration the target height can be inquired in the geography information system and be corrected continuously, and the localization error is analyzed and simulated, the result indicates that the corrected height error can improve the height precision, then improve the level precision, the improved the level precision will improve the height precision, then the integral localization precision can be improved.