Research on the method of searching and tracking of the time-sensitive target through the mega-constellation

The time-sensitive target has the characteristics of high-speed motion and an uncertain model, which present challenges to the observation process. Aiming at the problem of searching and tracking the time-sensitive target in a region, the scheduling method of the mega-constellation based on grids coding is proposed in this paper. Above all, the observation problem is assessed, after which the grids coding model of observation resources and tasks is constructed. Afterwards, the dynamic updating process of probability is established as a Markov state transition, taking into consideration the movement of the time-sensitive target during the searching phase, and the dynamic prediction model of target position for target tracking is founded, which takes into account the unpredictability of the time-sensitive target model. Ultimately, the mega-constellation searching technique is developed with the enhancement of information entropy of covering grids as the objective function. Based on the optimal acquisition probability of grids, a method for determining the field-of-view center grid code is established to realize cooperative tracking. It is proved by experiments that, the continuous tracking of time-sensitive targets can be realized and the percentage of searches achieved within half an hour is greater than 92%, which is 10% to 35% higher than the conventional methods.(c) 2023 Elsevier Masson SAS. All rights reserved.