Task Scheduling Method for Data Relay Satellite Network Considering Breakpoint Transmission

The increasing demands for space-based data transmission pose a great challenge to task scheduling of tracking and data relay satellites (TDRSs). In order to improve the working efficiency and task completion rate of the data relay satellite network (DRSN), for the first time, we propose a novel application mode for DRSN, in which data breakpoint transmission is considered. In the mode of data breakpoint transmission, a single task can be reasonably split into multiple subtasks and thus scheduled in multiple time windows. At first, the task scheduling model of DRSN considering breakpoint transmission is defined. In addition, a two-stage method is designed to generate a high-quality initial solution. Moreover, we propose an adaptive variable neighborhood descent combined with a tabu list (AVND-TL) to iteratively improve the initial solution. In AVND-TL, two task reallocation neighborhood structures are incorporated and adaptively selected during the solution search process, which effectively prevent the algorithm from falling into local optimum. Finally, extensive experiments are carried out to verify that the proposed breakpoint transmission mode and AVND-TL together can significantly improve the task completion rate and resource utilization rate.