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Yasutaka OGAWA Yuji KATOH Kiyohiko ITOH
A color subcarrier in a television (TV) signal via a broadcasting satellite is expected to be an effective medium for future frequency dissemination. The difficulty inherent in use of the broadcasting satellite is the Doppler shift due to the drift around the geostationary orbit. Therefore, it is important to measure the Doppler frequency shift of the color subcarrier precisely and to establish a technique which cancels out the effect. The Doppler frequency shift measurements were carried out by using a Medium-Scale Broadcasting Satellite for Experimental Purposes (Yuri). This paper reports the results observed at Sapporo. The important results are as follows. The Doppler shift amounts to about 1108 in the worst case. However, when the transmitted frequency is controlled at the Kashima transmitting station, the Doppler shift may be canceled out to within a few parts in 1010 at Sapporo. Furthermore, it is expected that we may usually obtain the standard frequency with an accuracy of the order of 1012 if the Doppler shift compensation is employed at both transmitting and receiving points. These results are important when we construct a nationwide frequency dissemination system using a broadcasting satellite.