GPS Multi-channel Common-View Based Experimental Research of Time and Frequency Traceability and Measurement

GPS multi-channel common-view is a technique of time and frequency transfer with high accuracy, which can be used to achieve traceability for local time and frequency reference. The conception of time and frequency traceability is presented in this paper. The general principles of GPS multi-channel common-view and the detailed analysis of traceability in time and frequency metrology based on this technique are described. The measurement uncertainty of common-view is evaluated according to a long baseline comparison experiment, including the time measurement uncertainty of traceability to a national and international standard as well as the frequency measurement uncertainty of traceability to a national standard. Moreover, rather than time deviation, a new method is put forward to evaluate Type A time uncertainty via GPS multi-channel common-view technique. According to experimental results and analysis, time is measured with the combined expanded uncertainty of less than 15ns (2s) with respect to the UTC of a national standard, and is less than 18ns (2s) when it is trace to international standard. Meanwhile, frequency is measured with the combined expanded uncertainty of less than 10-13 (2s) after Day of averaging when it is trace to a national standard.