摘要
本文探讨了利用GPS水准网改善我国似大地水准面的原则和方案，讨论了目前可能获得的实际精度和分辨率。提出了对GPS定位和坐标系转换等的相应要求。
Summary
The principle for the improvement of the Chinese quasi-geoid is suggested that the
development and the future plan for the local economy should be the bases for a design
used to improve the resolution and accuracy of a local quasi-geoid. It is not necessary to
set up a unified resolution and accuracy for the whole Chinese quasi-gedid, it is due to
the extremly unequal development in economical constiuction for various areas of China.
It is demonstrated that the main way to improve the Chinese quasi-geoid is GPS
leyelling.
The main goals for the improvement of the Chinese quasi-geoid in 90's are that
the accuracy of the differences of the height anomalies (ADHA) in the east part in
China is ±1 .5m (including the interpolation points); The resolution of the local quasi-
geoid (RLG) in this area is 70km×70km: The mean seperation of the GPS levelling
points (MSGP) in the same area is 70km. In the middle part in China the ADHA.
RLG and MSGP are planedtobe±2m, 130km× 130km, and 130km respectively. In the
west part in China, they are planed to be±3m,350km ×350km, and 250km respectively.
According to these goals the total points of GPS levelling network in China will not
be less than 650.
If the accuracy for the relative positioning of GPS is 1ppm, for coordinates trans-
formation is ±5m, for levelling is 4th order levelling, and the MSGP is 70km, 130km,
250km, then the accuracy estimation formulae for the height anomalies of the GPS lev-
elling line (L (km)) will be ±0. 022,±0.028 ±0.031 repectively.
If the ±1m accuracy for geoid is wanted to be obtained in China. 0.5-0.7ppm
relative positioning accuracy for GPS is needed, therefore to take some measurements
especially to improve the broadcasting emphemeris of GPS is obviously necessary for
China.
出处
《测绘学报》
EI
CSCD
北大核心
1993年第2期87-93,共7页
Acta Geodaetica et Cartographica Sinica
