中文摘要：

为解决太阳同步回归轨道的标称设计问题，提出一种基于高精度重力场的半解析优化方法。建立地球非球形引力摄动阶数为几的高精度重力场解析模型，并分离出引力摄动的长期项和长周期项。构建回归轨道从半长轴到平交点周期的对应关系，平交点周期变化随引力摄动阶数的提高而逐渐收敛。通过微分修正迭代算法所确定的半长轴相对于传统J2摄动模型的半长轴确定值具有更高的精度和更好的稳定性。考察摄动短周期项影响下的密切交点周期，结果表明其受初始位置（平近点角）影响较大，变化范围为0．015s，并由此给出精确回归轨道优化设计的基准：不同的初始位置上满足星下点轨迹严格回归的半长轴期望值。

英文摘要：

Aimed at the nominal design of repeat-groundtrack orbit for sun-synchronous satellites, a semi-analytical optimization method in the high precision Earth gravity field is proposed. The high precision analytical model about Earth gravity field with the order of zonal harmonics J15 for non-spherical gravitational perturbations is firstly presented. And the perturbations derived as function of mean orbital elements and time can be integrated out secular and long-periodic terms of perturbations with respect to mean anomaly. A corresponding relation from semimajor axis to mean nodal period of repeatgroundtraek orbit is derived, which concludes that the mean nodal period converges with the increase of order of perturbations. With the iteration algorithm of differential correction, the determination of semimajor axis shows a better performance in numerical precision and stability than J： perturbation model. The influence of short-periodic perturbations is finally considered in determining the osculating nodal period and the numerical case shows that the osculating nodal period with the variation range of 0. 015 s is affected greatly by the initial position （mean anomaly） of the satellite. Therefore, the expected semimajor axis that satisfies repetition of groundtrack depends on the different initial positions of satellites, which can be taken as the criterion in designing high precision repeat-groundtraek orbits.