#br# 基于POMDP的机载网络信道接入策略研究

针对机载网络随机竞争类媒介接入控制(medium access control,MAC)协议在网络负载较重时性能下降严重、接入门限值设置缺乏理论依据和多优先级业务服务质量无法有效支持等问题,提出一种基于部分可观测马尔可夫决策过程的信道接入策略。在以不同优先级分组占用信道代价作为目标函数的基础上建立动态规划方程,采用状态空间压缩方法对问题求解进行简化,得到各优先级分组间理论近似最优接入门限值的数学表达式,可为不同优先级分组的接入决策过程提供理论依据并实现接入冲突的有效控制。仿真结果表明,该算法能够有效提高数据传输的时延、成功概率等性能,满足军事航空通信中数据传输的实时性和可靠性需求。

Research on channel access strategy in airborne network based on POMDP

A channel access strategy based on partial observable Markov decision processes (POMDP) is presented in allusion to the problem of performance degrades seriously when load becomes heavy, the access threshold value settings is lacked in the theoretical basis and unable to effectively support the quality of serive requirement of multi priority service of the random competition medium access control protocol in airborne network. The dynamic programming function is established by which based on channel occupation cost of different priority burst as the objective function, the compact state space method is adopted to simplify the solution finding, the expression for the theory approximately optimal access threshold value within the different priority burst is worked out. The value can provide theoretical foundation for access decision processes of different priority burst and can effectively control the access collision within different priority burst. The simulation results show that transmission performance of delay and success probability can be improved obviously,the real time and reliability demands of data transmission in military aeronautical communications are satisfied.