Research On Distributed Wireless Time Synchronization Technology Of Sensor Network

In recent years,wireless node instrument systems equipped with navigation satellite timing services have become more and more popular.During our country's geological exploration mission,it is inevitable to face the challenge of complex environment.The wireless node instrument system is very conducive to surveying tasks in complex terrain due to its portable characteristics and has a very low construction cost.Compared with the wired node instrument system,the wireless node instrument system has the characteristics of independent timing and positioning.For data collection,time synchronization is an important factor affecting the accuracy of geological exploration.Therefore,improving the time synchronization stability of the wireless node instrument system is particularly important to ensure the performance of the wireless node instrument system.In this thesis,the auxiliary timing method based on wireless communication technology is studied to solve the possible signal blocking problems in the complex area of the wireless node instrument system with navigation satellite timing.And from the aspect of wireless time synchronization timing precision optimization,the detailed research of theory and experiment is carried out.The main work and innovations include:The synchronization optimization algorithm based on Kalman clock discipline is researched and analyzed.The algorithm is based on the theory of minimizing error and gives the time state prediction equation,observation equation and estimation equation.And they carried out hardware design and software implementation and analyzed and compared the results obtained from experimental tests.This algorithm and software and hardware design are used as the theories and tools for analyzing and researching time synchronization in this thesis.It introduces,analyzes and implements the time service method of broadcast communication.The second broadcast timing protocol and its convergence conditions in multi-device network communication are proposed.And use this as the basis for the subsequent analysis of the stability of time synchronization.Detailed modeling analysis and hardware implementation of the multi-source fusion flight time delay optimization algorithm are carried out.Based on the weighted average theory,the multi-source fusion flight delay optimization algorithm and a single flight delay algorithm are theoretically analyzed.The experimental results also verify the obtained theory.And prove the feasibility of the multi-source fusion flight delay compensation scheme.