System requirements for satellite laser ranging time transfer

To increase the accuracy of time transfer to hundreds of picoseconds, we have proposed a two way technique using the Japanese geodetic satellite Ajisai. The system would involve two satellite laser ranging (SLR) ground stations simultaneously ranging to the satellite, then depending upon the orientation of the satellite, reflect the laser pulse to the other ground station. When the fire and reception time from both stations are compared, a time transfer system with an approximate accuracy of 100 ps is possible. This paper describes the experimental arrangement and the characteristics of Ajisai, the laser ranging system at the CRL Tokyo station, and the steps we are taking to develop a system capable of SLR two-way time transfer.<<ETX>>