摘要
以小卫星群作为平台的天基分布式雷达具有多种用途。沿航向直线排列是分布式小卫星群的一种特殊轨道构形。由于阵列的等锥角线和等多普勒频率线重合,给SAR成像和地面运动目标检测的信号处理带来了极大的便利。受到地球自转的影响,多颗卫星采用同一轨道飞行并不能真正实现沿航向直线分布。为了克服地球自转的影响,现提出满足Hill方程的一种基本不消耗燃料的轨道设计,使多颗卫星飞行在不同的轨道上而实现真正的沿航向直线分布。数学分析表明它可以有效消除地球自转的影响。结合SAR成像的仿真结果证明了该方法的有效性。
Spacebome distributed radar carried by a cluster of micro-satellites is suitable for many applications, Along-track linear formation is a special orbit design. Using this along-track linear array, the ground Doppler lines and pattern nulls of antenna array can be overlaid effectively, which brings much convenience of signal processing for SAR and GMTI. But because of the Earth＇s rotation, an along-track array can not be obtained by making all the satellites use identical orbit but separated by a short time interval. To eliminate the effect of Earth＇ s rotation, we develop a new orbit design method in this paper. Designed with new method, each satellite has a different orbit but all satellites form a real along-track 1-D array. It is also a solution of Hill＇ s equations. The mathematic analysis and computer simulations of SAR imaging show the validity of the methods.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2005年第5期663-667,共5页
Journal of Astronautics
基金
国家自然科学基金(60402039)
关键词
小卫星
分布式雷达
沿航向排列
轨道设计
Micro-satellite
Distributed radar
Along-track formation
Orbit design
