INTELSAT two-way time transfer experiments among Japan, Korea, and Taiwan

The first two-way time transfer experiments using an INTELSAT Ku-band satellite in eastern Asia in cooperation between the Communications Research Laboratory (CRL, Japan), Korea Research Institute of Standard and Science (KRISS, Korea), and the Telecommunication Laboratory (TL, Taiwan) were carried out during 1992. The CRL-KRISS experiment attained a short term precision of better than 1 ns. The CRL-TL experiment suffered from a low C/N/sub 0/ ratio which made the short term precision greater than 1 ns. The long term averaged residuals contained a periodic noise signal which we believe was the result of a Doppler shift in the frequency of the signal caused by the relative motion of the satellite. A MITREX compatible modem under development at CRL exhibited a linear correlation with frequency offsets that were similar to the noise in the data.<
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