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利用其高度低于地球同步高度的圆轨道星座实现地球覆盖,有其先天不足之处。椭圆轨道星座(例如俄罗斯的闪电系统)可为所选择的地理区域提供更有效的覆盖。由赤道平面内的椭圆环带及临界倾角分别为i_1=63.435°与i_2=116.565°的两个椭圆环带组成星座系统,这种设计对经度与纬度抑或白天的覆盖时间可以获得重点覆盖,选取多卫星系统的轨道平面间隔及相位布局可以产生重复的地面轨迹。就补偿长期项摄动及保持星座完整性所需的周期性修正机动而消耗的燃料而言,椭圆轨道比之低高度圆轨道要少些。椭圆型星座的其它优点还包括:有利的北半球/南半球的驻留比、食区时间更短以及减轻了对轨道碎片的脆弱性。此外,对相同的轨道周期而言,发射椭圆轨道所需的轨道能量比发射圆轨道要少。当中高度椭圆星座提供的覆盖与低高度圆轨道的覆盖相同时,采用的卫星个数较少(从而所需的运载工具亦较少)。这些都直接使系统成本更廉价。总之,利用椭圆轨道具有的两个多余自由度(即偏心率及近地点幅角),允许星座设计师在实现非常合适的经度、纬度及时间覆盖的同时,仍保持系统成本低廉。
The use of its height below the height of the Earth’s circular orbit constellation to achieve the Earth’s coverage, there are inherent deficiencies. Elliptical orbit constellations, such as the Russian lightning system, provide more efficient coverage of the selected geographic area. The constellation system consists of two elliptical annular zones with i_1 = 63.435 ° and i_2 = 116.565 °, respectively, in the equatorial plane and the critical dip angle. The design can provide important coverage for the longitude and latitude or the daytime coverage time. Multi-satellite system orbital plane spacing and phase layout can produce repeated ground trajectory. Elliptical orbits are lower than low altitude circular orbits in terms of compensating for long term term perturbations and periodic corrective maneuvering to maintain constellation integrity. Other advantages of elliptical constellations include a favorable dwell ratio in the northern hemisphere / southern hemisphere, shorter food-area time, and reduced vulnerability to orbital debris. In addition, the orbital energy required to launch an elliptical orbit is less than that of a circular orbit for the same orbital period. When mid-high elliptical constellations provide the same coverage as low-altitude circular orbits, fewer satellites are used (and fewer vehicles are needed). All of these directly make the system cheaper. In summary, the use of elliptical orbit with two extra degrees of freedom (ie, eccentricity and perigee) allows constellation designers to achieve very appropriate longitude, latitude and time coverage while still maintaining system cost.