长条带卫星线阵影像区域网平差研究

本文首先比较了基于轨道参数和基于卫星状态矢量的航天影像定位模型，提出了一种针对非精密星历数据的轨道拟合与状态矢量插值方法，并在飞行坐标系中建立了适合长条带卫星影像定位的轨道修正模型。其次，分析了地球自转对卫星线阵影像严密定位建模的影响，通过对姿态航偏角的适应性处理，建立了基于地固地心直角坐标系卫星状态矢量的航天线阵影像构像方程和区域网联合平差模型。最后以中国西部测图工程的塔里木盆地4对(8景)SPOT5/HRS长条带立体影像为数据源，针对不同控制点数目与分布，进行了不同方案的组合定位试验。结果表明：稀少控制点条件下检查点统计精度达到了8.09 m。

Maximum Likelihood Estimation in Mixed Integer Linear Model with P-norm Distribution

The integer parameters must be primarily estimated in the GNSS and INSAR application, which essentially introduces a special mixed integer model with both real- and integer-valued parameters from mathematical point of view. Up to now, all methods for mixed integer model are based on the least squares criterion. In this paper, the parameter estimation will be investigated in mixed integer model with the P-norm distributed observation noises. First of all, we will employ the maximum likelihood estimation theory to derive the criterion for integer searching, considering the fact that only real parameters can be differentiated but not the integer parameters due to their discrete property, and further verify that least squares based integer searching criterion is just a case with normally distributed noises. Secondly, the approach and iterative procedure are given for estimating p, searching integers and solving real-valued parameters. Finally, the simulated experiments are implemented to verify the correctness of the derived formulae and proposed algorithm.