大跨度天基数据链的TDD时隙调度分析与优化

针对天基数据链系统卫星间的传播时延较大且节点间距离变化较大等特点，提出了一种提高时频资源利用率、提升系统容量、减小时延的方法。在时分多址与空分多址相结合的接入方式下，进行了时隙调度的分析与优化，利用卫星星座的空间复用与大跨度传播时延特性，采用时隙编排、收发状态调整、帧格式优化等手段，将信道利用率和系统容量提升了1倍，将卫星节点在某一方向获得服务的平均等待时间缩短为原来的1/4，提高了天基数据链系统的服务质量。

Analysis and Optimization of TDD Time Slot Scheduling for Long-span Space-based Data Link

According to the characteristics of serious delay and dynamic variations of distances between the nodes in space-based data link system,this paper proposes a scheduling method to improve the utilization of time-frequency resource,enhance the capacity and reduce the delay.The time slot scheduling is analyzed and optimized by taking advantages of the properties of the space multiplexing and the long-span propagation delay of satellite constellation under the combination of time division multiple access(TDMA) and space division multiple access(SDMA).Simulation results show that by using time slot arrangement,transceiver status adjustment,and frame format optimization,the proposed method doubles the channel utilization and system capacity,reduces the average waiting time to 1/4 of the original one,and enhances the service quality of space-based data link system.