Small elliptic target reentry forecasting method under sparse data condition

The invention discloses a small elliptic target reentry forecasting method under a sparse data condition. N circles of data collected in the past 5 days are processed, a numerical method is adopted tocarry out track determination on the single circle of data, the Kepler root number is adopted as a root number system, a semi-numerical method is adopted to carry out track integration, and a least square method is adopted to fit a ballistic coefficient of a reentry target. Compared with the prior art, the invention provides a reentry forecasting method combining the numerical method and the semi-numerical method for the characteristics of the sparse data and the small elliptic orbit. The problems that under the condition of sparse data, the multi-circle data joint orbit determination residual error is too large or not convergent, and the ballistic coefficient is difficult to determine through single-circle data orbit determination are effectively solved. 本发明公开了一种稀疏数据情况下小椭圆目标的再入预报方法，处理过去5天采集到的N圈数据，采用数值方法对单圈数据分别进行