| In order to conserve battery power in very dense sensor networks, usually we take such a method: some sensor nodes may be put into the sleep state while other sensor nodes remain active for the sensing and communication tasks. On the one hand, when the RF module is at work status, energy consumed is the highest. When it is in sleep status, energy consumed is the lowest. On the other hand, when all nodes are at work status and the density of the nodes is very high, a large number of unnecessary energy will be consumed and data collected will be highly relevant. Nodes in the same region will cause the conflict of data packets when they compete for channels. So the scheduling problem becomes inevitable.First of all, this thesis makes a comparison among the random sleep scheduling algorithm, the random sleep scheduling algorithm based on the information of neighbor nodes and the random sleep scheduling algorithm based on the energy of the nodes by MATLAB simulation tool.Secondly, this thesis introduces the cyclic cellular automata theory on the basis of these algorithms, describes in detail two cyclic cellular automata models: the G-H model in the integer domain and the G-H model in the real domain and is simulated by MATLAB tool. Then the thesis compares the differences between the cyclic cellular automata and the random sleep scheduling algorithm. It is concluded that when the demand of the coverage of the networks is not very strict, the cyclic cellular automata is a well way to improve the life of the networks.Finally, based on IEEE 802.15.4/ZigBee standards and SoC technology, this thesis selects the CC2430 which is made in Chipcon Company as a micro-chip RF transceiver and starts to design the hardware of the node. The article describes in detail the overall design idea, as well as the circuit design process of sub-modules. After the implementation of the hardware platform, this thesis sets up the development environment and lays a foundation for further work. |
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