One-way frequency and time transfer in the frame of the INTELSAT two-way experiment

During 1995, a synchronization experiment in a one-way mode was performed at IEN, using a DBS (Direct Broadcasting Satellite) receiving station, in the frame of the international two-way synchronization experiment based on INTELSAT satellites at 307° East. To stabilize the received frequency at the level required by the 2500A MITREX modem, two approaches were followed: first the Low Noise Converter oscillator was locked by injection via a standard frequency in the Ku-band and successively the satellite beacon frequency has been used as reference to lock an oscillator of the down conversion chain. The instability of the receiving station in both configuration plus the measurement system has been evaluated receiving the PRN codes from different laboratories, after having removed the effect of the satellite movement. Using the second equipment setup, one-way synchronization measurements were regularly performed since October 1995, according to the schedule for the European Laboratories, during their range sessions. Correcting the measurement results for the satellite position obtained from the range data of at least three European Laboratories, the time and frequency transfer capabilities in the one-way mode, for such equipment and stations configuration, have been evaluated