摘要
根据天基雷达和地面回波点的几何关系分析了地球自转对天基雷达地面回波多普勒频率的影响。研究表明:在卫星高度一定时,偏航幅度和偏航角只与卫星的轨道倾角和星下点纬度有关;偏航角在近似±3.78°区间里变化,偏航幅度接近于1;星下点纬度为零时,偏航角和偏航幅度随着轨道倾角的增大而单调递增,并且在赤道上空35 754 km时,多普勒频率为零,卫星与地球同步运行;地球自转使地面回波无模糊的角度-多普勒迹发生了弯曲。该研究结果为天基雷达杂波抑制和动目标检测提供了依据。
The effect of the Earth＇ s rotation on the doppler fequency is analyzed based on the geometrical relationship between space -based radar （SBR） and the clutter patch of interest. The result is as follows： Firstly, the crab magnitude and crab angle depend only on the SBR orbit inclination and its latitude at a given orbit. Secondly, the crab angle varies between - 3.78° and ＋ 3.78° and the crab magnitude approximates 1. Thirdly, when SBR＇ s latitude is zero, they increase monotonously with the increase of orbit inclination. At an altitude of 35754 km, the doppler frequency becomes zero, the satellite is on the geosynchronous orbit. Moreover, the Earth＇ s rotation makes SBR＇ s no fuzzy angle - doppler trace inflect. The above conclusions provide a basis for SBR clutter suppression and moving target detect （MTD）.
出处
《电讯技术》
北大核心
2009年第4期6-9,共4页
Telecommunication Engineering
基金
国防预研基金资助项目(9140A07010607DZ0206)
