Teng Gao

Energy-Efficient Cluster Head Selection Scheme Based on Multiple Criteria Decision Making for Wireless Sensor Networks

Energy efficiency is an essential issue in the applications of wireless sensor networks (WSNs) all along. Clustering with data aggregation is a significant direction to improve energy efficiency through software. The selection of cluster head (CH) is the key issue in the clustering algorithm, which is also a multiple criteria decision making (MCDM) procedure. In this paper, a novel fuzzy multiple criteria decision making approach, which is based on trapezoidal fuzzy AHP and hierarchical fuzzy integral (FAHP), is introduced to optimize the selection of cluster heads to develop a distributed energy-efficient clustering algorithm. Energy status, QoS impact and location are taken into account simultaneously as the main factors that can influence the selection of cluster heads while each factor contains some sub-criteria. Fuzzy multiple attribute decision making is adopted to select optimal cluster heads by taking all factors into account synthetically. According to these criteria, each node computes a composite value by using fuzzy Integral. Then this composite value is mapped onto the time axis, and a time-trigger mechanism makes the node broadcast cluster head information. The rule that “first declaration wins” is adopted to form the cluster. Simulation results denote that our proposed scheme has longer lifetime and more eximious expansibility than other algorithms.

Passive cluster-based multipath routing protocol for wireless sensor networks

Energy efficiency and quality of service (QoS) are both essential issues in the applications of wireless sensor networks (WSNs) all along, which are mainly reflected in the development of routing and MAC protocols. However, there is little design for achieving the dual performances simultaneously. In this paper, we develop a practical passive cluster-based node-disjoint many to one multipath routing protocol to satisfy the requirements of energy efficiency and QoS in practical WSNs. Passive clustering approach is put to use in the first round, while active clustering technique is taken in the other rounds. Implementation of smart delay strategy makes the cluster distribute uniformly, as well as lessen the number of nodes that have taken part in routing. Among cluster heads, a node-disjoint many to one multipath routing discovery algorithm, which is composed of the optimal path searching process and multipath expansion process, is implemented to find multiple paths at the minimum cost. The simulation results show the proposed protocol achieved very good performance both in energy efficiency and QoS.

A novel node-disjoint multipath routing protocol for wireless multimedia sensor networks

Aimed at energy conservation and QoS requirement, a novel node-disjoint multipath routing protocol for wireless multimedia sensor networks is proposed in this paper. Source routing approach is adopted to generate multipath. By overall considering several attributes, the model of path efficiency is defined through fuzzy multiple criteria decision making approach, which is based on trapezoidal fuzzy AHP and hierarchical fuzzy integral. Two parameters — path ID and path efficiency — are introduced into the forwarding process of intermediate node, so that only the appropriate RREQs are forwarded, the overhead is reduced accordingly. The simulation results indicates that, compared with SMR and TinyONDMR protocol, the overhead of route establishment of the new protocol is lower and energy distribution of node of path is better. Furthermore, the new protocol causes higher communications energy efficiency under the condition that no propagation delay is increased.

Research on Localization Method Based on RSSI Ranging-Error Compensation

To improve the localization precision based on RSSI ranging in wireless sensor networks, a localization method based on the ranging-error compensation is presented. By analyzing the tendency of RSSI ranging error with different distance, we propose the mathematical model and the experiment results about ranging-error compensation. It is proved that the method based on ranging-error compensation effectively improves the node ranging precision in wireless sensor networks and the localization precision.

Clustering Algorithm Based on Fuzzy Comprehensive Evaluation for Wireless Sensor Networks

Energy efficiency and quality of service (QoS) are both required performances in the practical applications of wireless sensor networks. Clustering is one of main methods to achieve performance tradeoffs. In the clustering algorithm, the selection of the cluster heads is based on some criteria, which provides the opportunity to implement the performance tradeoffs. In this paper, a clustering algorithm based on fuzzy comprehensive evaluation method (CAFCE), is proposed to achieve both energy efficiency and QoS performance. Residual energy, location, number of neighbors, queue length and channel quality are taken into account as the factors that can influence the selection of cluster heads. Fuzzy comprehensive evaluation method is adopted to select appropriate cluster heads in order to achieve energy efficiency and QoS performance simultaneously. Each node obtains its own evaluation value. Then this value is mapped onto the time axis, and a time-trigger mechanism enables the node broadcast cluster head advertisement in the corresponding time slice. The rule of minimum transmission power is adopted to form the cluster. Simulation results denote that CAFCE algorithm has longer lifetime and better QoS performance than other algorithms.

A New Hybrid Localization Technology of Wireless Sensor Networks

Localization is one of the key technologies of wireless sensor networks. This paper presents a new hybrid localization algorithm developed based on Maximum Likelihood Estimation (MLE) and MAX-MIN algorithm, which improves localization accuracy. The conclusion is got from simulation experiments analysis that its best for anchor nodes to be deployed around the networks and the layout of anchor nodes will be the more regular the better. Moreover the cost is taken into account, which is low-cost.