卫星重力梯度恢复地球重力场的频谱分析

Spectral analysis for recovering the Earth′s gravity potential by satellite gravity gradients

根据仪器功率谱密度和重力位系数阶方差的定义,本文建立了卫星重力梯度测量噪声功率谱密度与重力场模型的误差阶方差的直接对应关系,并基于此讨论了重力梯度测量精度、卫星轨道高度以及运行时间对地球重力场恢复精度的影响.相比于传统的基于最小二乘法评估卫星载荷噪声对地球重力场恢复精度的影响而言,本文提出的方法简单、直接,有助于快速设计和确定卫星重力测量计划的有关参数.

Direct relationship between the power spectrum density of the satellite gradiometry and the coefficients of the Earth＇s gravity potential is established based on the definitions of the instrument＇s power spectrum density and the Earth＇s gravity field potential, and then the effect of gravity gradient measurement accuracy, the altitude of the satellite, and the operation duration on recovering of Earth＇s gravity field is analyzed by using this method. This method is simple and direct compared with the others based on the least square approach, and is very useful to design and verify the parameters for the Earth gravity recovery missions.