摘要
提出了一种适用于星载GPS自主定轨的改进的地球引力近似函数方法(improved gravity acceleration approximation function, IGAAF)。对IGAAF方法的性能进行评估,结果表明:IGAAF方法的计算耗时小于45×45阶球谐模型;拟合系数容量仅为200～320 kB;引力加速度的截断误差(3D RMS)处于1×10~2～1×10~3 nm/s^2量级,小于每颗低轨卫星自主定轨所需的最优阶次球谐模型(GOCE:105×105,CHAMP:85×85,GRACE-A:65×65, ZY3/TerraSAR-X:55×55);将IGAAF方法应用于星载GPS自主定轨试验,相比于球谐模型,不会降低自主定轨精度。IGAAF方法在保证定轨精度的同时兼顾计算效率与系数容量的平衡,在星载GPS自主定轨的工程化应用中具有较强的实用价值。
We present an improved gravity acceleration approximation function(IGAAF) suitable for space-borne GPS real-time onboard orbit determination. The test of analyzing IGAAF’s performances demonstrates that IGAAF maintains the truncation error in the magnitude of 1×10~2-1×10~3 nm/s^2 only with the computational burden less than a 45×45 spherical model and a 200-320 kB RAM requirement for fitting coefficients, and that its accuracy is slightly superior to the spherical models with optimal degree and order for autonomous orbit determination(105×105 model for GOCE, 85×85 for CHAMP, 65×65 for GRACE-A and 55×55 for ZY3 and TerraSAR-X). Compared to the spherical model, IGAAF does not decrease the orbit accuracies. The IGAAF method attains a good trade-off between computational efficiency and coefficient capacity without decreasing the orbit accuracy, so it is of strong engineering value for space-borne GPS autonomous orbit determination.
作者
龚学文
王甫红
GONG Xuewen;WANG Fuhong(School of Geodesy and Geomatics,Wuhan University,Wuhan 430079,China;Collaborative Innovation Center for Geospatial Technology,Wuhan 430079,China;GFZ German Research Center for Geosciences,Potsdam 14478,Germany)
出处
《武汉大学学报（信息科学版）》
EI
CSCD
北大核心
2019年第3期371-377,共7页
Geomatics and Information Science of Wuhan University
基金
国家自然科学基金(41374035
91638203)~~
关键词
自主定轨
IGAAF
定轨精度
计算效率
系数容量
autonomous orbit determination
IGAAF
orbit accuracy
computational efficiency
coefficient capacity
