Recently, the time and frequency benchmark laboratory and time division of the national time center of the Chinese Academy of Sciences (CAS) focused on the "135" technology goals of the center, and jointly launched the Lintong Pucheng common view time comparison test based on the Beidou, using the Beidou dual frequency common view method and the time comparison accuracy of 1.5 nanoseconds.

The national time service center of the Chinese Academy of Sciences (hereinafter referred to as "national time service center"), formerly known as the Shaanxi Observatory, was founded in 1966. It is the only scientific research institution in China that specializes in time frequency basic research and applied research. It bears the task of producing, maintaining and broadcasting the national standard time (Beijing time) in China. The big technology infrastructure, long and short wave time service system, has built the only test platform for integrated satellite and satellite navigation and time service in China, which has made important contributions to the construction and development of China's satellite navigation system.

The comparison results of 1.5ns show that the time comparison link based on Beidou satellite is continuous and reliable, which can meet the technical requirements of the long and short wave time service system, and can be equipped with other existing time traceability means between the time frequency reference system and the long short wave time table, so as to ensure the independent, reliable, safe and stable operation of China's long short wave timing system.

The long wave time service system (BPL) and the short wave timing system (BPM) are the main means of time service in the national time service center. The short wave time table was basically completed in 1970, and the short wave service was officially launched in 1981. After upgrading and upgrading, the short wave time service station is now broadcasting the standard time and standard frequency signal for 24 hours every day for four hours. The mid power long wave platform was built in 1979, and the high power long wave station began to provide time service in 1983, enabling China's terrestrial radio time service to reach the international advanced level. The achievement was awarded the first prize of national science and technology progress in 1988. The long short wave time service system has formally undertaken the standard time and standard frequency broadcasting task since the beginning of 70s.

The BPL and BPM long and short wave time service broadcasting system of the national time service center has become an indispensable national science and technology support infrastructure project and social public welfare facilities, providing national standard time and standard frequency services for many industries and departments such as national economic development, national defense construction, national security and so on. It has undertaken several important national space launches, such as rocket and satellite launch. Task.