结合短帧优先的权重轮询AFDX端系统发送策略

提出一种新型的端系统虚链路调度（VL）策略，该策略在短帧优先基础上结合权重轮询（WRR）进行调度，既确保了重要短帧的优先级又可以平衡其他不同优先级信号的延迟上限。应用网络演算理论推导了基于该新型调度策略的端系统不同虚链路的延迟上界，研究了最大延迟上界与不同权重比及其帧长之间的关系，并建立了基于OPNET的航空电子全双工交换式以太网（AFDX）网络模型，仿真分析新型调度策略与短帧优先、带权重轮询调度算法下端系统数据的发送延迟。结果表明，该新型调度策略有效可行，降低了短帧虚链路的最大延迟时间，提高了长帧数据中较重要任务数据的处理带宽，适用于具有较多重要短帧并具有不同优先级数据的机载系统网络。

Short-frame prior scheduling with weighted round robin transmission strategy in AFDX terminal system

A new scheduling strategy of terminal system virtual link (VL) is put forward, which is based on the short-frame prior scheduling and integrated with weighted round robin (WRR).The new approach ensures the priority of the important short-frame and balances the delay upper bound of other different priority signals. Based on the theory of network calculus, the paper derives the delay upper bound of different virtual links through the new combinatorial scheduling strategy and researches the relation among the maximum delay upper bound, weight ratio and frame length. The Avionics Full Duplex Switched Ethernet (AFDX) network model based on OPNET is established, and the terminal system data transmission delay under the three scheduling strategies is simulated and compared. The results show that the new scheduling strategy can reduce the maximum delay time of short-frame virtual link, and improve the processing bandwidth of relatively important task in long-frame data transmission. It is feasible and applicable to airborne system network with more short-frame and different priority data flow.