The Research Of Low-power And Scalable Hierarchical Topology Control In Underwater Acoustic Sensor Networks

As a system of information processing, underwater acoustic sensor networks (UASNs)can collect, process and transmit the marine information effectively. If the sensor nodes are deployed in hostile and unattended marine environment, monitoring the Marine information will spend a lot of energy. However, sensor nodes are battery operated, with limited life and difficult to be replaced, therefore algorithms in UASNs must be designed with high energy efficient and balancing energy consumption to prolong the network life. As a kind of hierarchical topology control algorithms, Low Energy Adaptive Clustering Hierarchy(LEACH) can balance energy consumption and prolong lifetime of the network. Under the background of UASNs, LEACH is deeply investigated and two ideas for improving LEACH algorithm are proposed in this paper, The main contents include:1. This paper deeply investigates the UASNs architecture and topology control algorithms,and analyzes the requirements of topology control algorithms in UASNs based on underwater acoustic communication environment and the characteristics of network nodes.2. Based on the analysis of the optimum cluster size in UASNs, LEACH-T algorithm for UASNs is put forword. LEACH-T don't need to focus on the controlling of the nodes or increasing the amount of communication traffic,there are two times cluster heads elections in each round. LEACH-T algorithm can reduce UASNs energy consumption by stabilized the cluster heads number and uniformity distributed of cluster heads, it can improve performance of UASNs.3. In the expanded UASNs, the network topology is changeable, and the node engegy is heterogeneous. On the basis of analyzing this problem,this paper proposes LEACH-ET algorithm for UASNs, LEACH-ET algorithm can reduce and balance UASNs energy consumption, it improves the performance of UASNs.4. The optimum cluster size is tested with the help of Matlab simulation software.According to the principle of optimal clustering, two kinds of improved algorithm are applied to the unexpanded and extended networks. The network node number, survival of each round distribution of the energy consumption and node energy are simulated. The proposed LEACH-T and LEACH-ET algorithm are compared with LEACH algorithm, LEACH-E algorithm on energy efficiency and the balance of energy consumption. Simulation results demonstrate that LEACH-T algorithm performs better on energy efficiency, and LEACH-ET algorithm performs better on balancing energy consumption.