Two-way satellite time transfer (TWSTT): USNO operations and calibration services

摘要

The U.S. Naval Observatory maintains a large number of dedicated antennas, modems, and related hardware worldwide in support of high-precision DoD and non-DoD TWSTT time and frequency transfer users. This paper will present a small portion of our operations as an example. Recent TWSTT measured time and frequency comparison results, how we monitor the transmit and receive paths, some recent work done on evaluation of X-band high-power-amplifiers and effects on TWSTT, basics of calibration of high-precision time and frequency systems using TWSTT, and an estimate (approx 1.1 ns) for a recent co-located Ku-band TWSTT calibration are given.