Real-Time Data Aggregation for Contention-Based Sensor Networks in Cyber-Physical Systems
Real-Time Data Aggregation for Contention-Based Sensor Networks in Cyber-Physical Systems
复制标题
网络物理系统中基于竞争的传感器网络的实时数据聚合
DOI：
10.1007/978-3-642-31869-6_45
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
X. Jia
中科院分区：
文献类型：
--
作者：
Qin Liu;Yanan Chang;X. Jia
无线传感器网络在信息物理系统的信息采集和数据收集中发挥着重要作用。研究了无线传感器网络中采用CSMA/CA MAC层协议的实时数据汇聚问题。该问题是，对于一个给定的sink，一组传感器节点和延迟界，以最大限度地提高平均传输成功概率的延迟范围内的所有传感器节点。在CSMA/CA协议中，成功概率和期望传输时延对节点干扰高度敏感，在大规模的网络物理系统中，节点干扰往往很高。我们将系统时间划分为固定大小的时间帧，并将节点的传输调度为时间帧。在纯TDMA协议中，时间帧的大小远大于时隙的大小。同一父节点下的所有子节点的传输被调度在同一时间帧中，并且它们以CSMA/CA方式竞争信道接入。在这个系统模型中，数据聚集树的构建对于最大化数据收集的成功概率变得非常重要。我们解决联合路由和调度问题，首先构建一个聚合树，最大限度地减少节点干扰。然后，我们提出了一个有效的贪婪调度方法来分配时间帧的传感器节点。大量的仿真结果表明，我们提出的方法可以提高成功概率显着。
Wireless sensor network plays an important role in information collection and data gathering in cyber-physical systems. We study real-time data aggregation problem for wireless sensor networks that use CSMA/CA MAC layer protocols. The problem is, for a given sink, a set of sensor nodes and a delay bound, to maximize the average transmission success probability of all sensor nodes within the delay bound. In CSMA/CA protocols, the success probability and the expected transmission delay are highly sensitive to node interference, and the node interference is often very high in the large scale cyber-physical systems. We divide the system time into time-frames with fixed size and schedule the transmission of nodes into time-frames. The size of time-frame is much larger than the time-slot in pure TDMA protocols. The transmissions of all child nodes under the same parent are scheduled in the same time-frame and they compete the channel access in CSMA/CA fashion. In this system model, the construction of data aggregation trees becomes very important in maximizing the success probability of data collection. We solve the joint routing and scheduling problem by first constructing an aggregation tree that minimizes the node interference. Then, we propose an efficient greedy scheduling method to assign time-frames to sensor nodes. Extensive simulations have been done and the results show that our proposed method can improve the success probability significantly.