Measurement and calculation on system error caused by SATRE modem

The system error caused by equipment is the major factor that restricts time synchronization performance between stations. The two-way satellite time and frequency transfer (TWSTFT) is the most accurate time synchronization method that is generally accepted currently. SATRE Modem is the common reference terminal of TWSTFT. When the temperature, carrier power and code pattern change, its reference time delay and transmit time delay will change also. In this paper, The measurement method of reference time delay and transmit time delay of SATRE Modem is introduced, furthermore, the measure data in different environment is obtained. After the analysis and discussion, the variation characteristics of reference time delay and transmit time delay of SATRE Modem is given. It can provide technology support for reducing the system error and improving accuracy of time synchronization.