Hybrid clock synchronization method based on timestamp-free interaction and unidirectional message propagation

Abstract

The invention relates to a hybrid clock synchronization method based on timestamp-free interaction and unidirectional message propagation, and belongs to the technical field of wireless sensor networks. The method can be executed simultaneously with a broadcast mechanism according to a one-way message propagation synchronization mode. The timestamp-free interactive synchronization can implicitly acquire synchronization information in a network data stream, and the method performs joint design and optimization on a timestamp-free interactive synchronization mechanism and a unidirectional message propagation mechanism, so that seamless fusion of a time synchronization function and an actual wireless sensor network is realized. According to the method, the joint estimation of clock frequencyoffset, phase offset and fixed time delay can be realized without carrying out synchronization information transmission by a special synchronization message, the node synchronization communication overhead is effectively reduced, and the clock phase offset estimation performance is improved.

Description

technical field [0001] The invention belongs to the technical field of wireless sensor networks, and relates to a hybrid clock synchronization method based on time stamp-free interaction and one-way message propagation. Background technique [0002] From the perspective of statistical signal processing, the time synchronization problem in wireless sensor networks can be regarded as a parameter estimation problem for clock frequency offset and clock phase offset. However, if we only pay attention to the acquisition of the clock phase offset parameters without estimating the clock frequency offset, the existence of the clock frequency offset will lead to the deviation of the node clock again, and the clock deviation will continue to accumulate, and even affect the life cycle of the sensor network . In order to maintain the synchronization accuracy between nodes, it is necessary to perform resynchronization operations periodically, but frequent synchronization process will bri...

AI Technical Summary

Problems solved by technology

For the one-way message propagation synchronization method, although it can be executed in parallel with the broadcast mechanism, it is impossible to accurately distinguish the clock phase offset and the fixed delay of data packet transmission because only one-way synchronization message interaction is performed.

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