Wireless Sensor Networks, Clustering Algorithms And Routing Protocols

Based on the project of large-scale wireless sensor networks (WSNs), this thesis focuses on how to improve the node energy efficiency. Under the analysis of the traditional clustering routing protocols, this thesis proposes a new clusters algorithm BCR and two routing protocols, namely CMHR and Ad-CMHR.In BCR, when nodes in the area of the overlapping that caused by cluster heads broadcast join the cluster, the measurement is not longer the distant, but have to consider the cluster heads energy and the distance between cluster head and sink. BCR can balance well the energy consumption of the cluster and the simulation results also validate the effectiveness of BCR.CMHR changes the mode that signal hop transmit the data intra-cluster in traditional cluster routing protocol. After introducing the CMHR design idea, this thesis employs the theoretical model to analysis the minimum transmission radius under keeping the network connectivity and the optical cluster heads which in multi-hops mode. Then this thesis designs the CMHR protocol in detail, especially in the mode of multiple hops transmission and time distribution mechanism, meanwhile, analysis suitability of multi-hops and single-hop transmission, problem of node converting, relationship between cluster heads and jumps. The simulation results show that the CMHR protocol can reduce the energy consumption and extend the network lifetime as well.In order to adapt the lager-scal network application, Ad-CMHR routing protocol is the improvement of CMHR, which has the following merits: 1) Ad-CMHR reflects the uniform clustering during the selection process of initialization cluster head; 2) Ad-CMHR considers node's surplus energy when rotate cluster head; 3) Ad-CMHR can establish routing between cluster heads by using adjacency cluster head information table, without any interactive messages; 4) Ad-CMHR improves the algorithm of intra-cluster slot statistical, avoid extra energy consume because idle waiting, meanwhile, it also plays a role of shorting the delay of data transmission intra-cluster. The simulations results finally verify the efficiency of Ad-CMHR.