Abstract
Pseudolites have potential to enhance the performance of GNSS, and research and developments have been conducted in several aspects. If pseudolites were mounted on aircrafts, its GNSS-like signal would be stable augmentations that would improve the accuracy, availability, and integrity of GNSS-based positioning systems. A pseudolite installed on a stratospheric airship, or a high-altitude unmanned aerial vehicle, could be used as a continuous GNSS augmentation, while a pseudolite on a helicopter could be used as a temporal navigation aid for emergency vehicles in hazardous area. In order to establish fundamental technologies for such a system, the augmentation tests using a GPS pseudolite installed on a helicopter were conducted. The position of the pseudolite antenna underneath the helicopter, which is analogous to the GPS ‘precise ephemeris’, was successfully determined with a few centimeters accuracy by inverted GPS method. Also, the results demonstrate the efficacy of integrating the pseudolite signal with GPS.
