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Acquired by the Fengyun4 meteorological satellite ranging system, the distance from the ground station on the earth to the satellite is the main factor influencing the accuracy of the satellite’s orbit determination. After introducing the working principles and procedure of the Fengyun4 ranging system, the techniques used to improve the ranging precision are analyzed from different aspects, including the measurements in the stations’ site coordinates, the delay caused by ground equipment, satellite transponder, propagation through atmosphere and the time synchronization of different stations.