有限推力和脉冲推力是研究航天器轨道拦截问题的两大类方法。该文基于C-W方程建立了航天器远程拦截的相对运动方程,并进行了无量纲化;以能量最省为性能指标,应用Legendre伪谱法对拦截轨道进行优化,并检验结果的最优性。仿真结果表明,该方法精度高、鲁棒性强,验证了Legendre伪谱法在航天器远程拦截轨道优化设计中的正确性和有效性。以固定时间拦截理论为基础,在脉冲推力假设下,提出了一种新的最优拦截方案,它以机动时刻和所需速度冲量表征。将其与Legendre伪谱法的优化结果进行了比较,指出新的最优拦截方案能够更灵活满足拦截任务要求。 Finite thrust and impulsive thrust are two broad categories of methods for studying spacecraft orbital interception. In this paper, the relative motion equation of spacecraft remote interception is established based on the C-W equation and dimensionless. With the most energy as the performance index, the Legendre pseudospectral method is used to optimize the intercept trajectory and test the optimality of the results. Simulation results show that the proposed method is accurate and robust, which proves the validity and correctness of the Legendre pseudospectral method in the optimization design of spacecraft orbit. Based on the theory of fixed time interception, a new optimal interception scheme is proposed under impulsive thrust assumption, which is characterized by maneuvering moment and required velocity impulse. Compared with the optimization results of Legendre pseudospectral method, it is pointed out that the new optimal interception scheme can more flexibly meet the requirements of interception mission.