Effects of the Ionosphere on Telecommunications, Satellite Positioning, and Electric Navigations

摘要

The origin of NICT is in the routine monitoring and studies of the ionosphere for keeping long distance telecommunications with shortwaves. This role has been decreasing with the develop ment and wide uses of satellite communication, however, it is still fundamental infrastructure. In addition, the study of behavior of ionosphere become important in the utilities of satellite naviga tion. The global navigation satellite system(GNSS) is expected as an important and fundamental technique to build the secure and safety society. One is the example of the utility is electric navi gation with GNSS. Because it is difficult for electric navigations to use any additional information from the ground station, the improvement of positioning precision become important. It is neces sary to provide the ionospheric information precisely and on real time for contributing the next generation utilities with GNSS.