Regional Positioning System Using TV Signals from Broodcasting Satellites

本文作者提出了一种利用地球静止卫星的日本国内定位系统。事实证明，利用广播卫星发射的电视同步信号进行距离测量，通过后处理可以实现高精度定位。为了实现移动站的实时定位，必须将卫星位置信息发送给用户。作者试图用一颗通信卫星来传输它们。与此同时，他们还试图使用通信卫星作为定位的发射机。因此，有必要获得卫星的确切位置。他们试图建立一个系统，通过VSAT（甚小孔径终端）监测和传输通信卫星的位置，进行实时定位。采用31位的64 kHz m序列信号作为对地静止通信卫星JCSAT-1在150e的测距信号，从卫星与三个VSAT地面站之间的三个距离推导出卫星的位置。它们在主站通过切换接收频率直接接收卫星发回的测距信号，并通过卫星接收两个从站。主站测得的绝对距离与卫星控制中心同时测得的值吻合较好，标准差为2m。我们在第三年尝试了三颗地球同步卫星的定位，即BS在110 E，CS在162 E， JCSAT在150 E。这项技术是在头两年开发出来的。根据卫星分配推导出的协方差矩阵的分量表明，本定位方法推导出的点在纬度方向上分布广泛，其中2 drms为72 m。

A domestic positioning system using geostationary satellites in Japan has been propose by the present authors. It was proved that high accurate positioning was possible, though the post processing, by exploiting TV synchronous signals transmitted from broadcasting satellites for range measurement. In order to attain a real-time positioning at mobile stations, the satellite position information must be sent to users. The authors tried to use a communication satellite to transmit them. At the same time, they also tried to use the communication satellite as a transmitter for positioning as well. Thus, it is necessary to obtain the exact position of the satellite. They tried to establish a system to monitor and transmit the position of communication satellite by VSAT (Very Small Aperture Terminal) for real-time positioning. A 31- bit m- sequence signal of 64 kHz was used as a range finding signal to the geostationary communication satellite JCSAT-1 at 150 E.In the proposed system, the satellites position was deduced from three ranges between the satellite and three VSAT earth stations. They were measured at the master station by switching the reception frequency to receive range finding signals sent back from the satellite directly and the two slave stations through the satellite. The measured absolute ranges at the master station agree well with the values simultaneously measured at the satellite control center and have the standard deviation of 2m.We tried the positioning with three geostationary satellites, namely BS at 110ﾟE,CS at 162ﾟE,and JCSAT at 150ﾟE in the third year. The technique, developed in the first two years was used. The deduced points, of which the 2 drms is 72 m, by the present positioning method scattered widely in the latitudinal direction as the components of the covariance matrix, which is deduced from the satellites allocation, imply.