CAJ | 학술논문

基于垂线偏差与高程基准无关的性质,由GPS水准实施垂线偏差的低通滤波,并精确估计其二次变化率,最终实现无重力数据的长距离、高精度跨障碍高程传递.对新方法的滤波及拟合过程进行数值分析,并将其截断误差转换为频域表达形式,再通过球谐函数建立代表误差与重力场阶方差的关系式.考虑到局部重力场的高频甚高频差异,根据Graaff Hunfer经验公式和不同地形类别的代表误差统计值,将Tscherning-Rapp模型改造为区域阶方差模型,以精确估计具体地形条件下的代表误差.杭州湾大桥跨海高程控制测量的实验结果与模拟分析一致:31 km跨海高程传递成果与独立的一等几何水准比较,最大较差19 mm,优于二等几何水准精度.
기우수선편차여고정기준무관적성질,유GPS수준실시수선편차적저통려파,병정학고계기이차변화솔,최종실현무중력수거적장거리、고정도과장애고정전체.대신방법적려파급의합과정진행수치분석,병장기절단오차전환위빈역표체형식,재통과구해함수건립대표오차여중력장계방차적관계식.고필도국부중력장적고빈심고빈차이,근거Graaff Hunfer경험공식화불동지형유별적대표오차통계치,장Tscherning-Rapp모형개조위구역계방차모형,이정학고계구체지형조건하적대표오차.항주만대교과해고정공제측량적실험결과여모의분석일치:31 km과해고정전체성과여독립적일등궤하수준비교,최대교차19 mm,우우이등궤하수준정도.
Based on the independence of vertical deflection and height datum, a new method was offered for the precise long-distance height transference across obstacle without gravity data, in which GPS leveling has become a low-pass filter for vertical deflection and its second order change rate has been evaluated accurately. Numerical analysis was done for filtering and fitting in the new method, and its truncation error was converted into frequency domain. Consequently, the correlation was acquired between the representation errors and the geopotential degree-variances through spherical harmonic expansion. Considering the difference of regional earth's gravity fields in high and very high frequency bands, the Tscherning-Rapp model was modified as regional geopotential degree-variance model in order to evaluate accurately the representation errors corresponding to all kinds of topography, by using "Graaff Hunfer" experiential formula and statistical coefficients of representation errors with topographic classifications. The experiment of height control survey across 31 km width was done for Hangzhou Bay Bridge. The result was in accordance with the simulation. It was compared with the first order leveling, and the maximum difference was 19 mm. The precision was higher than the second order leveling.