In Japan there is widespread use of car navigation system that utilize the US GPS (Global Positioning System). However, due to the shadows of city buildings and overhead freeways, etc., so it is not possible to capture a sufficient number of GPS satellites, giving rise to the problem of difficulty in position measurements. In order to resolve this problem, the focus has been on the technology of pseudolites, which are used instead of GPS satellites, and which are established in locations where there are insufficient numbers of satellites, making it is possible to measure position using the same receiver. Therefore, with the purpose of constructing a vehicle-orientated safety assistance system utilizing GPS, basic test verifications were carried out to find out if high precision position detection is possible for swiftly moving bodies such as automobiles, etc., using pseudolites instead of GPS satellites. From these tests, the possibility of high precision (1 meter or less) position detection of swiftly moving bodies (120km/h) was confirmed. In addition, it became clear that there are still issues such as pseudolite layout and radio wave interference with GPS satellites.
Abstract