INFLUENCE OF ELLIPSOIDAL HEIGHT ERROR ONSEVEN-PARAMETER TRANSFORMATION
Wang Jiexian 1,2) ; and Qiu Yang Yuan 1)
1)Department of Surveying and Geo-Informatics, Tongji University,Shanghai 2000922)Key Laboratory of Advanced Engineering Survey of SBSM,Shanghai 200092
Abstract:WGS84 coordinates can be transformed to local coordinates through sevenparameter space transformation, but the ellipsoidal height of local coordinates usually cannot be precisely known. It should be probed weather the imprecise height will affect the transformation.The least square approach is used for solving the transformation parameters. Moreover the changes of parameters caused by error of ellipsoidal height of local coordinates are deduced. Finally, it is demonstrated that even though the ellipsoidal heights are not precise enough, its influence on coordinate transformation can be ignored in the range of 100 km×100 km.