Bibliothèque de L'IMIST/CNRST

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Université Abdelmalek Essaâdi

Wireless sensor networks (WSN) restricted means in terms of processing potentiality and power reserve supply a variety of significant issues which make them a fruitful field to numerous investigation efforts. Icreasing the sensing range of an attention area to highly monitor and detect all potential events that can occur within it, maintaining and improving the connectivity to provide more reliability of the network and allow a facile and real cooperation between the whole network nodes, or extending the lifetime to reach the end of the desired system assignment correspond to the main objective of WSN researches. WSN deployment represents a key design step. This is because, on the one hand, the theoretical models and assumptions often differ from real environnemental charateristics and performance at the deployment real area. On the other hand, the WSN deployment requires a strong expertise of the communication stack. In this project, we have concentrated on the deployment problem, that is deploying or placing sensor nodes in optimal positions within a target area, in order to maximise the relevant information gathering, and to provide consistent communication links between the network sensor nodes; gathering and communcating are both simultaneously required to perform and reach a high degree of the desired goal for which the system has been designed. In this thesis, we propose a novel approach for the WSN deployment based on the use of simultated annealing to obtain close to optimal solutions, for the placement of sensors in terms of minimizing of the number of hops between all the nodes of the target region and the sink node while covering as much of the interest area as possible. By reducing the number of hops, the paths become short which decrease the number of the relay nodes and their surcharge, such as computing and maintaining routine tables of long sequence paths, and eliminate long retransmission in case of transmisssion error. According to this schema, the proposed approach of optimal deployment of WSN also to improve energy saving. Finally, this thesis shows the flexibility of this technique for studying the influence of different parameters of interest at a design stage of the network, prior to the real deployment of WSN nodes.