The Research On TDOA Based Synchronization And Localization Technologies For Wireless Sensor Network

The wireless sensor network was first used in the vast natural environment, for example, to monitor forest fire, to observe the animals' and plants' growth, to collect data in the marine atmosphere.The initial small sensor has been currently developed into mass application in agriculture and animal husbandry management, monitoring of industrial production and even national defense and security. At present the meaning and development needs are, by a large amount of pre-deployed or temporary sensor points in the wireless sensor network, to gather huge amount of physical data monitoring information, therefore to support people's decisions with relevant references. The research and discussion of this subject in recent years has been very active. The national 863 project and natural science fund have given preferential support to its study.WSNs' research depth varies with the special field, and the aspects of research have taken on variety in recent years. This paper introduces briefly the general situation of WSNs, gives a detailed introduction of its localization algorithms, especially the range-based ones, and proposes clock offset compensation-based joint algorithm of clock synchronization and node localization for clock asynchrony WSNs.With the anchors' position known, this algorithm synchronizes the anchors' clock by compensating clock offsets, To obtain chock synchronization between anchor pairs. All sensors periodically broadcast signals to each other, signal arrival time measurement(TOA) devices will cause so as to have time to frequency offsets, with the accumulation of the source transmits the signal time generate clock offsets. the initial TDOA error due to the clock offset of sensors can be mitigated by a compensation operation. To achieve the goal of improving the positioning accuracy of the tag nodeIn the last chapter, the algorithm is applied in the engineering implementation, and a comprehensive real-time localization system is designed. This paper wholly introduces the framework of hardware(Including stm32?NA5TR1 RF chip)and software, communication protocol and localization schedule and so on. Scenario tests proves that this experiment has achieved the expectance of engineering design, which provides solid basis for its broader development perspective in future.