Abstract:
The elevation accuracy of AW3D30 SRTM3 v4.1 and ASTER GDEM V3 are analyzed through the area of the mountainous hills in parts of Guangdong. The data of 730 km lines along Guangzhou, Huizhou, Shaoguan and Qingyuan are collected by vehicle dynamic PPP, the WGS84 coordinates of dynamic points calculated by CSRS-PPP positioning service system, geodetic height of dynamic points converted into normal height by gravity field model EIGEN-6C4, and finally, the elevation of three digital elevation models are checked. The results show that the average errors of AW3D30, SRTM3 v4.1 and ASTER GDEM V3 are, respectively, 0.55, 0.17 and 1.59 m, and the root mean square 3.78, 5.84 and 8.88 m. The average error amplitude of AW3D30 in different altitudes is relatively small, within 2.18 m; the average error of SRTM3 v4.1 has a negative correlation with altitude, and the average error gradually changes from positive value to negative value with the increase of altitude; the average error of ASTER GDEM V3 is within (0 m, 2.18 m altitude range and is about 2 m and -2.28 m in (250 m, 800 m range. The root mean square error and standard deviation of AW3D30 decrease with the increase of altitude, while SRTM3 v4.1 increases with the increase of altitude. ASTER GDEM V3 has no significant rule, which is better than 7.69 m in (100 m, 250 m, and better than 9.86 m in other regions.