针对延迟容忍移动传感器网络(Delay Tolerant Mobile Sensor Networks,DTMSN)提出一种基于网络编码的广播传输机制(Netcoding-based Broadcast Transmission scheme,NBT)。NBT中,基站(Base Station,BS)将原始数据分批进行传输,每个批次包含的原始数据包的数量一定;BS将同一批次数据包以单播方式传输给不同传感器节点时采用的编码向量互不相关,传感器节点之间采用泛洪的机制交换彼此缺少的编码数据包。由于BS对原始数据包进行了编码,因此传感器节点具有相同编码数据包的可能性大大降低,从而减小了节点间的数据相关度,有效降低了广播时延。在随机路点移动模型(Random WayPoint,RWP)下的仿真结果表明,与目前广播时延最小的泛洪机制相比,NBT能够在通信开销基本相同的情况下有效降低广播传输时延。
A Netcoding-based delay-sensitive Broadcast Transmission scheme(NBT) is proposed for Delay Tolerant Mobile Sensor Network(DTMSN).In NBT,the data are batched transmitting from Base Station(BS) and each batch contains finite number of original packets.BS encodes the original packets of one batch with uncorrelated vectors and unicasts them to the different sensor nodes in its coverage,and the sensor nodes exchange encoded packets with each other in flooding mechanism.Because of the packets are encoded,the probability that sensor nodes have the same packets is low and the correlation of data between sensor nodes is reduced too.Simulation results show that the proposed NBT scheme has lower broadcast delay than flooding scheme with the same communication cost under Random WayPoint(RWP) model.