无线Ad Hoc网络中基于活跃节点数预测的时隙ALOHA算法  

A Slotted ALOHA Algorithm Based on Predictive Number of Active Nodes for Wireless Ad Hoc Networks

作　　者：黄盛 HUANG Sheng(Southwest China Institute of Electronic Technology,Chengdu 610036,China)

机构地区：[1]中国西南电子技术研究所

出　　处：《电讯技术》2019年第12期1443-1450,共8页Telecommunication Engineering

摘　　要：针对采用时隙ALOHA算法的无线Ad Hoc网络,考虑数据包到达的动态性与数据包传输的随机性,以最大化吞吐量为目标,同时满足数据队列稳定性,构建了关于接纳控制与竞争接入的随机优化问题。由于在时隙ALOHA算法中数据包传输的最优概率取决于无线Ad Hoc网络中数据队列非空的活跃节点数,提出了一种基于活跃节点数预测的时隙ALOHA算法。该算法要求无线Ad Hoc网络中的所有发送节点实时地侦听通信信道的忙闲状态,计算基于信道状态的活跃节点数条件期望,从而动态地预测无线Ad Hoc网络在不同时刻的活跃节点数,达到网络节点依据局部网络状态信息自适应地优化数据包传输概率的目的。仿真结果表明,所提算法能够有效估计无线Ad Hoc网络在每个时隙的活跃节点数,从而显著提升网络吞吐量并且降低数据包的平均排队时延。A wireless Ad Hoc network employing the slotted ALOHA algorithm is studied.Accounting for dynamic data packet arrival and random data packet transmission,a stochastic optimization problem is formulated for admission control and competitive access,which aims to maximize the throughput and satisfy the data queue stability.Because the optimal probability of data packet transmission in the slotted ALOHA algorithm depends on the number of actives nodes with a non-empty data queue,a slotted ALOHA algorithm based on the predictive number of active nodes is proposed.This algorithm requires all the transmitting nodes in the wireless Ad Hoc network to sense whether the communication channel is busy or idle in real-time,compute the conditional expectation of active node number based on the channel state,and dynamically predict the active node number of wireless Ad Hoc network in different time slot.Simulation results show that the proposed slotted ALOHA algorithm based on the predictive number of active nodes can effectively estimate the number of active nodes for each time slot in the wireless Ad Hoc network,thereby it can significantly improve the network total throughput and decrease the average queuing delay of data packets.

关 键 词：无线Ad Hoc网络 时隙ALOHA 接纳控制 竞争接入 

分 类 号：TN929.5[电子电信—通信与信息系统]