帧生成过程作为CCSDS AOS两级多路复用机制的第一级,其性能直接影响着AOS系统的传输效率和时延特性。本文对AOS协议中帧生成算法进行研究,分析了在包到达率服从泊松分布条件下,高效率帧生成算法的帧生成时间均值。针对高效率帧生成算法中可能出现的在较长时间内没有足够多的包到达,导致帧生成时间过长,从而造成帧生成时延超过业务所允许的最大时延情况,提出了一种自适应帧生成算法。理论分析和仿真结果表明,本算法不但能克服高效率帧生成算法中可能出现的大时延问题,并且比传统的等时帧生成算法具有更高的信息传送速率。
Frame generation process is the first stage of the multiplexing mechanism of Advanced Orbiting Systems,whose performance has a great effect on the transmission efficiency and time delay of AOS.In this paper,the frame generation algorithm in AOS protocol is studied.The average frame generation time of high efficiency frame generation algorithm is analyzed,on condition that the packet arrival rate distribution is Poisson distribution.An adaptive frame generation algorithm is also proposed to solve the problem that the generation delay exceeds the allowed maximum service time,which is caused by lack of enough packets arriving in a long period of time.Theoretical analysis and simulation results show that the proposed algorithm can not only solve the large time delay problem of high efficiency frame generation algorithm,but also get higher information transmission rate than the conventional periodic frame generation algorithm.