Advanced Satellite-Based Frequency Transfer at the 10−16 Level

Advanced satellite-based frequency transfers by two-way carrier-phase (TWCP) and integer precise point positioning have been performed between the National Institute of Information and Communications Technology and Korea Research Institute of Standards and Science. We confirm that the disagreement between them is less than 1×10-16at an averaging time of several days. In addition, an overseas frequency ratio measurement of Sr and Yb optical lattice clocks was directly performed by TWCP. We achieved an uncertainty at the mid-10-16level after a total measurement time of 12 h. The frequency ratio was consistent with the recently reported values within the uncertainty.