In many wireless sensor network applications, it should be considered that how to trade off the inherent conflict between energy efficient communication and desired quality of service such as real-time and reliability of transportation. In this paper, a novel routing protocols named balance energy-efficient and real-time with reliable communication (BERR) for wireless sensor networks (WSNs) are proposed, which considers the joint performances of real-time, energy efficiency and reliability. In BERR, a node, which is preparing to transmit data packets to sink node, estimates the energy cost, hop count value to sink node and reliability using local information gained from neighbor nodes. BERR considers not only each sender' energy level but also that of its neighbor nodes, so that the better energy conditions a node has, the more probability it will be to be chosen as the next relay node. To enhance real-time delivery, it will choose the node with smaller hop count value to sink node as the possible relay candidate. To improve reliability, it adopts retransmission mechanism. Simulation results show that BERR has better performances in term of energy consumption, network lifetime, reliability and small transmitting delay.
Wireless sensor networks(WSNs) are energyconstrained,so energy saving is one of the most important issues in typical applications.The clustered WSN topology is considered in this paper.To achieve the balance of energy consumption and utility of network resources,we explicitly model and factor the effect of power and rate.A novel joint optimization model is proposed with the protection for cluster head.By the mean of a choice of two appropriate sub-utility functions,the distributed iterative algorithm is obtained.The convergence of the proposed iterative algorithm is proved analytically.We consider general dual decomposition method to realize variable separation and distributed computation,which is practical in large-scale sensor networks.Numerical results show that the proposed joint optimal algorithm converges to the optimal power allocation and rate transmission,and validate the performance in terms of prolonging of network lifetime and improvement of throughput.
Inter-femtocell interference becomes serious when femtocells are densely deployed. To mitigate the inter-femtocell interference, this paper proposes a cluster-based bandwidth allocation algorithm. We create femtocell clusters by constructing a weighted interference graph and allocate bandwidth to each cluster based on a Nash bargaining solution(NBS). Simulation results show that the cluster-based bandwidth allocation algorithm can reduce the inter-femtocell interference and meet the minimum rate constraint of each cluster.
Kai MaLiang LiJie YangZhi-Xin LiuXin-Bin LiXin-Ping Guan
