The Research Of Node Positioning Based On The Particle Swarm Optimization-simulated Annealing Algorithm In WSN

Since the early21st century, Wireless Sensor Network, as a kind of newtechnologies which to gather, process and transmit information, has made greatprogress both in the aspect of theoretical research and practical application. Using alarge number of stationary or moving sensors, WSN constructs the network by theway of self-organization and multiple hops. Then it deals with the message of theperception targets and sends them to the observers finally. As one of the keytechnologies of WSN, positioning technology is vital to the processing of information,and paid more and more attentions by researchers nowadays.Existing location algorithms can generally be divided into two categories: therange-free location algorithms and the range-based location algorithms. As a kind ofrange-free location algorithms, DV-Hop algorithm is superior to the range-basedalgorithms in the aspect of saving cost and consuming energy. The operating principleof DV-Hop algorithm is that the algorithm utilizes the estimated distance of theanchor node to the unknown node replacing the actual distance between nodes.Therefore, the positioning precision of DV-Hop localization algorithm is relativelylow. On the basis of ensuring low cost and low energy consumption, the main focus ofthis thesis is on reducing the positioning error of DV-Hop localization algorithm.According to the problems discussed above, consulting and analyzing a great ofreferences, the paper draws the experience of several optimization algorithms andthen puts forward the improved DV-Hop algorithm based on the particle swarmoptimization-simulated annealing algorithm (PSO-SA). The main principle of theimproved algorithm is applying the hybrid particle swarm optimization into in theprocess of calculating average jump distance in the DV-Hop algorithm. It caneffectively reduce the positioning error caused by the estimated average hop distanceand achieve the goal of improving the localization precision of WSN.Then, the paper carries on the simulation experiment to test the performance ofthe hybrid algorithm on the platform of MATLAB. The simulation experiment resultsshow that：compared with the existing several kinds of improved DV-Hop algorithm,the DV-Hop algorithm based on PSO-SA improves the positioning accuracy in acertain degree. Finally, the main work of the paper is summarized, and the prospects of thefuture research work are drawn.