星载干涉成像高度计双频基线定标方法

Dual-frequency Baseline Calibration Method of Spaceborne Interferometric Imaging Altimeter

在星载干涉成像高度计基线参数标定过程中,由于时间、传输路径的观测差异导致基线参数标定精度下降。为此,文章提出双频基线定标方法,基于双频同基线重叠观测区域数据实现基线状态标定性能的提升,有效降低干涉基线状态漂移造成的海面高程反演误差。在精确获取重叠区域海面高度条件下,利用在轨高精度基线测量和卫星姿态测量信息,联合高精度基线估计处理算法进行基线估计,将基线估计偏差的均方根降低至原来的1/4~1/5,可实现亚毫米、亚角秒的高精度基线估计精度,从而保证海面高度测量精度,为后续干涉成像高度计在轨定标方案的设计与基线高精度标定提供参考。

Regarding degradation of the parameter calibration accuracy due to observation differences in time and transmission path for the baseline calibration of spaceborne interferometric imaging altimeter,a dual-frequency baseline calibration method is proposed to improve the performance of baseline state calibration based on dual-frequency overlapping observation area data.The errors of sea surface height caused by drifting of interference baseline state are also effectively attenuated.Under the precise sea surface height in the overlapping area,the baseline parameters can estimate accurately depended on the combining between baseline states estimation processing algorithm,onboard high-precision baseline measurement and satellite attitude measurement information.The results of proposed method can reduce the root mean square of the baseline parameters estimate bias to 1/4~1/5 of the original.Sub-millimeter and sub-arcsecond high-precision baseline estimation accuracy for the method will provide useful ideas for the design of interferometric imaging altimeter calibration schemes and high-precision baseline calibration.