中国及周边区域ASTERGDEM与SRTMDEM高程对比分析及互补修复

Elevation comparison and complementary repair of ASTER GDEM and SRTM DEM in China and surrounding areas

本文分析了ASTER GDEM和SRTM DEM的获取方式,通过对两者在中国及周边区域高程的对比分析,得出两者高程间存在系统误差,前者高程比后者平均低4.9m。ASTER GDEM在许多区域特别是水域及高山区常存在明显粗差;SRTM DEM在特别是高山区域会出现空白区域,但其有效区域层次清晰、细节分明,无明显粗差,可靠性高。经过填补及高差约束限制修复,生成了无空白区域的SRTM DEM和可靠性更高的ASTER GDEM。

This paper analyzed ASTER GDEM and SRTM DEM acquisition modes,compared their elevations,concluded that there is a systematic error that ASTER GDEM is lower about 4.9m than SRTM DEM in china and surrounding areas.ASTER GDEM has obvious gross error at many regions especially water regions and high mountain regions.SRTM DEM has void areas especially at high mountain areas,but its detail is clear and layered at valid areas,without obvious gross error and with high reliability.By Filling and repairing with elevation difference constraint,it generated void-filled SRTM DEM and higher reliable ASTER GDEM.