Data gathering algorithms in sensor networks using energy metrics
Data gathering algorithms in sensor networks using energy metrics
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DOI：
10.1109/tpds.2002.1036066
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发表时间：
2002-09-01
影响因子：
5.3
通讯作者：
Sivalingam, KM
中科院分区：
文献类型：
--
作者：
Lindsey, S;Raghavendra, C;Sivalingam, KM
传感器网络由有限的电池功率和无线通信的节点组成，用于从现场收集有用的信息。以能量有效的方式收集感测到的信息对于长时间运行传感器网络至关重要。在[12]中，定义了一个数据收集问题，其中，在一轮通信中，每个传感器节点都有一个数据包要发送到远处的基站。当发送或接收分组时，在电子设备中存在某个固定量的能量成本，并且当发送分组时存在取决于传输距离的可变成本。如果每个节点将其感测到的数据直接发送到基站，则它将快速耗尽其功率。[12]中提出的LEACH协议是一种优雅的解决方案，其中形成集群以在向基站传输之前融合数据。通过随机化选择向基站传输的簇头，LEACH与直接传输相比实现了8倍的改进，如在节点死亡时测量的。在[14]中提出了LEACH的改进版本，称为LEACH-C，其中中央基站执行聚类以提高能量效率。在本文中，我们提出了一种改进的方案，称为PEGASIS（传感器信息系统中的节能聚集），这是一个接近最佳的基于链的协议，最大限度地减少能源。在PEGASIS中，每个节点只与近邻通信，并轮流向基站发送，从而减少了每轮消耗的能量。仿真结果表明，对于不同的网络规模和拓扑结构，当1%、25%、50%和100%的节点死亡时，PEGASIS的性能比LEACH好100%到200%。对于许多应用，除了使能量最小化之外，考虑在收集感测数据时引起的延迟也是重要的。我们捕捉这与能量x延迟度量和本计划，试图平衡从传感器网络收集数据的能量和延迟成本。由于大部分的延迟因素是在传输时间，我们衡量延迟的传输次数来完成一轮的数据收集。因此，当网络中可能时，可以通过允许同时传输来减少延迟。利用具有CDMA能力的传感器节点[111]，可以在干扰很小的情况下同时进行数据传输。在本文中，我们提出了两个新的计划，以尽量减少能量x延迟使用CDMA和非CDMA传感器节点。如果目标是仅使延迟成本最小化，则可以使用二进制组合方案来在并行通信的情况下以大约log N个延迟单位完成该任务，并且引起能量成本的略微增加。对于具有CDIVA能力的传感器节点，基于链的二进制方案在能量x延迟方面表现最佳。如果传感器节点不具备CDMA能力，则并行通信仅在空间上分离的节点之间是可能的，并且基于链的3级层次结构方案表现良好。我们比较了直接，LEACH和我们的计划在能量x延迟方面的性能，使用广泛的模拟不同的网络规模。结果表明，我们的计划执行80倍以上的直接计划，也优于LEACH协议。
Sensor webs consisting of nodes with limited battery power and wireless communications are deployed to collect useful information from the field. Gathering sensed information in an energy efficient manner is critical to operating the sensor network for a long period of time. In [12], a data collection problem is defined where, in a round of communication, each sensor node has a packet to be sent to the distant base station. There is some fixed amount of energy cost in the electronics when transmitting or receiving a packet and a variable cost when transmitting a packet which depends on the distance of transmission. If each node transmits its sensed data directly to the base station, then it will deplete its power quickly. The LEACH protocol presented in [12] is an elegant solution where clusters are formed to fuse data before transmitting to the base station. By randomizing the cluster-heads chosen to transmit to the base station, LEACH achieves a factor of 8 improvement Compared to direct transmissions, as measured in terms of when nodes die. An improved version of LEACH, called LEACH-C, is presented in [14], where the central base station performs the clustering to improve energy efficiency. In this paper, we present an improved scheme, called PEGASIS (Power-Efficient GAthering in Sensor Information Systems), which is a near-optimal chain-based protocol that minimizes energy. In PEGASIS, each node communicates only with a close neighbor and takes turns transmitting to the base station, thus reducing the amount of energy spent per round. Simulation results show that PEGASIS performs better than LEACH by about 100 to 200 percent when 1 percent, 25 percent, 50 percent, and 100 percent of nodes die for different network sizes and topologies. For many applications, in addition to minimizing energy, it is also important to consider the delay incurred in gathering sensed data. We capture this with the energy x delay metric and present schemes that attempt to balance the energy and delay cost for data gathering from sensor networks. Since most of the delay factor is in the transmission time, we measure delay in terms of number of transmissions to accomplish a round of data gathering. Therefore, delay can be reduced by allowing simultaneous transmissions when possible in the network. With CDMA capable sensor nodes [111], simultaneous data transmissions are possible with little interference. In this paper, we present two new schemes to minimize energy x delay using CDMA and non-CDMA sensor nodes. If the goal is to minimize only the delay cost, then a binary combining scheme can be used to accomplish this task in about log N units of delay with parallel communications and incurring a slight increase in energy cost. With CDIVA capable sensor nodes, a chain-based binary scheme performs best in terms of energy x delay. If the sensor nodes are not CDMA capable, then parallel communications are possible only among spatially separated nodes and a chain-based 3-level hierarchy scheme performs well. We compared the performance of direct, LEACH, and our schemes with respect to energy x delay using extensive simulations for different network sizes. Results show that our schemes perform 80 or more times better than the direct scheme and also outperform the LEACH protocol.