基于遗传算法的全球导航星座重构研究

The Research on Global Navigation Constellation Reconfiguration Based on Genetic Algorithm

全球卫星导航系统在部分卫星失效的情况下会引起地面导航性能下降甚至造成导航服务中断,但卫星数量众多的全球导航星座本身具有一定冗余性,在少数卫星失效时可以通过调整剩余工作卫星的轨道来降低失效影响。这种星座重构的维护方式具有快速响应故障和故障针对性强的特点。在星座重构中涉及到选取调整卫星及其轨道参数的问题。分析了用遗传算法实现星座重构方案优化的编码、适应度选取和进化过程,利用C++结合STK和GALIB完成了对24MEO+4GEO构成的全球导航星座在3颗以下MEO卫星失效时的星座重构方案优化,并对多种星座重构的轨道机动方案进行了对比。

The failure of the satellites in global navigation system will reduce the navigation capability and even intermit the navigation service sometimes. However, the constellation consists of numerous satellites so that it has the ability of adjusting the remains of satellites to recover from the discontinuity. This maintenance strategy called constellation reconfiguration is rapid-response and high-pertinence to the failure. The reconfiguration is to choose the satellites and their orbit elements. This paper analysed the encoding, fitness evaluating and evolving in genetic algorithm to achieve the reconfiguration. Then the reconfiguration schemes when less than 4 satellites failed in the 24MEO ＋ 4GEO constellation were optimized using C ＋＋ , STK and GALIB. Moreover, to accomplish the constellation reconfiguration via orbit transfer was also discussed in this paper.