Research And Design Of Sleep Strategy Based On Zigbee Wireless Sensor Networks

As the research and application of wireless sensor networks has become a hot spot of science and technology, it has been widely concerned. Because the wireless sensor network nodes are typically supplied by batteries and are randomly deployed in unattended environments for a long time, the energy consumption problem has become one of the key issues in wireless sensor networks. This thesis started from the energy consumption problem, analyzing the energy-saving problem of wireless sensor nodes. Afterward, dynamic sleep strategy was proposed.Dynamic sleep strategy is based on data from the node. First of all, the strategy gets the predicted value which is obtained by implementing single moving average and double moving average, and then uses the result of comparison between the predicted value and the actual data to determine the length of sleep duration dynamically. Secondly, in order to solve the problem of energy balance, coordinator counts the other nodes energy and calculates the value of global average energy, then notifies the other nodes of global average value, so that the network nodes can get the result of comparison between their own energy and average global energy which is one of the important factors that affects their sleep duration. Finally, in order to guarantee the communication between end devices and routers, this thesis conducted a study of time synchronization which can prevent two or more end devices in the local network from communicating with the parent node at the same time.The thesis made the design and implementation of dynamically adjusting sleep duration and energy balance function on OMNeT++, and then completed the design and development of dynamically adjusting sleep duration, energy balance and local synchronization on the CC2530 platform. The experiments achieved the desired aim. The experiments verified that the strategy could ensure the integrity of the data in the actual use process and high accuracy, and the strategy could extend the network lifetime, reaching the target of energy saving.