Matrix model estimation time synchronization method based on wireless network clustering topology

Abstract

The invention relates to a matrix model estimation time synchronization method based on wireless network clustering topology, and belongs to the technical field of wireless sensor network communication. The method comprises the following steps: S1, deploying network nodes, constructing a clustered topological structure, analyzing states of the nodes in different crystal oscillator frequency working modes, and establishing a logic clock model for matrix estimation; S2, according to the clustered topological structure, dividing the sychronization into inter-cluster synchronization and intra-cluster synchronization, selecting a high crystal oscillator frequency mode or a low crystal oscillator frequency mode, and estimating a clock drift relative parameter and a clock offset relative parameter through state functions established by different crystal oscillator frequencies; S3, respectively estimating the clock drift and the clock offset of the high and low crystal oscillator frequency modes by adopting maximum likelihood estimation through the estimated clock drift relative parameter and the estimated clock offset relative parameter, and periodically compensating the clock drift and the clock offset. According to the invention, the communication problem of the network nodes in different crystal oscillator frequency modes is effectively solved, and the network reliability and the synchronization precision are improved.

Description

technical field [0001] The invention belongs to the technical field of wireless sensor network communication, and relates to a matrix model estimation time synchronization method based on wireless network cluster topology. Background technique [0002] In recent years, the development of wireless sensor networks has become faster and faster, and the application fields have become more and more extensive. The network nodes are affected by various external factors, and the instability of network topology has become a key problem that needs to be solved urgently for time synchronization. The various requirements of various nodes distributed in the wireless sensor network, such as data collection time, time division multiple access, cooperative sleep, data fusion, flow control and other network control, require precise node time synchronization. Since there is a certain deviation between the clocks of different nodes after the network is formed, it is necessary to use clock sync...

AI Technical Summary

Problems solved by technology

[0003] The change of the wireless sensor network node itself (node ​​movement, failure, failure, new node joining, etc.) broadcast limitations, the limitation of the distance between the nodes, and the half-duplex communication mode of the wireless node, resulting in complex and changeable communication topology between nodes. Due to its own defects and the uncertainty generated by nodes in the transmission process, the existing clock synchronization protocol has great obstacles in the launch of certain applications.

Due to the interference change of the crystal oscillator frequency of the sensor node by external factors, the clocks of different nodes have different clock frequencies, resulting in clock drift and clock offset during data transmission, and the nodes in the network cannot transmit data accurately and effectively

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