The Study On Monitoring And Measuring Method And Software Design For Users' Signals In Time-Keeping System

The time-keeping system is the foundation and core of the standard time service. Besides generating and maintaining the time standard UTC(NTSC), the time-keeping system generates a large number of physical users'signals, including the standard frequency signals and the standard pulse signals, which are the time and frequency references for many applications. The current steering of UTC(NTSC) ensures the stability and the accuracy of UTC(NTSC) to a great extent, but it can not guarantee the quality of the users'signals. Therefore the study on monitoring and measuring method and software design of the users'signal in time-keeping system is very important to ensure the stable and reliable operation of time-keeping system. In this thesis, the monitoring and measuring method and software design are mainly elaborated.Firstly, the two major characteristics, the frequency stability and the frequency accuracy, are discussed. The importance of the frequency stability is analysed. The estimation formula which characterizes the frequency stability (Allan variance) in time-domain is presented.Secondly, Based on introducing the configuration of time-keeping system and users'signal distribution system, the monitoring and measuring method of users'signals is elaborated in detail: the selection of the parameter which reflects the fluctuating trend of users'signals is solved through analysing the time difference data by combining the first-order time series model with the second-order time series model of atomic clock. The important concept reference scale is given. At the same time the reference scale measuring the two types of users'signal stability and accuracy is given through the analysis of a large number of typical data.Thirdly, On the basis of the introduced the common error detection and correction algorithm, we found the Gauss statistical properties of difference data by analysing the experimental data from the statistical point of view. Based on the statistical properties, we proposed the improved threshold error detection and correction algorithm. The experimental results indicate that the proposed algorithm is efficient.Lastly, by the research on reference scale selection algorithm and the data error detection and correction algorithm, the design of monitoring and measuring software and the implementation method of various design modules is expounded. In addition, the function and using method of the software are introduced.