利用小波分析在轨识别空间目标轨道机动

空间目标的轨道机动往往隐藏在测量噪声中, 不容易被识别出来. 轨道机动可以引起机械能的突变, 用空间目标与航天器的单位质量机械能差作为机动识别的特征信号, 不会引入航天器本身的定轨误差. 用小波多尺度分解处理含噪声的特征信号, 对分解后的数据利用算法识别是否存在机动. 仿真结果表明, 本文提供的方法能有效识别空间目标的轨道机动. 

Detection of Space Target Orbit Maneuver on Board by Wavelet Analysis

It is difficult to detect an orbit maneuver of space target with measurement noise.Orbit maneuver brings step of mechanical energy.Mechanical energy difference of unit mass between space target and spacecraft is treated as signal of maneuver detection,so spacecraft orbit determination error won’t be added to the signal.In fact,the mechanical energy difference is only determinate by orbit radius of reference spacecraft and relative position and velocity between reference spacecraft and target.Wavelet analysis in differential scale was used to process the signal with noise.The signal has obviously step feature,and Harr wavelet function was selected in wavelet analysis because of its step feature which is same to the signal.Data after wavelet analysis was used to detect orbit maneuver.In the data process,a valve value is necessary.To some special orbit,we got the valve value through many simulations at first.The data process method which detect orbit maneuver of space target is verified by computer numerical simulation.The simulation shows that the correct rate of the detection of orbit maneuver raise when the maneuver level increase.The method can be used on board because it is automatic completely.