Ranging and Positioning Experiments for an Aircraft Using a Geostationary Satellite--The Effect of a Flight Route and Orbit Elements.

A ranging and positioning system using a geostationary satellite has been developed and its performance has been evaluated using an aircraft. This system can be applied to oceanic air traffic control and can be used at a ground station to determine positions of aircraft. An experimental system consists of a geostationary satellite, a ground station, an aircraft, and a pseudo-satellite, which is installed inside the ground station sod used as the substitute for another geostationary satellite. The Engineering Test Satellite V (ETS-V) of Japan was in the experiment. It is known that the positioning error increases a user approaches the equator in a positioning system using two geostationary satellites. This fact has been confirmed in this paper by experiment. It has also been shown that positioning errors can be decreased by using relative positioning m which the position of the ground station is used as a reference station. The use of old orbit elements increases the error of the predicted position of the geostationary satellite and therefore increases the positioning error of the aircraft. This has also been confirmed in the experiment. Furthermore, it has been shown that, in relative positioning, positioning errors do not increase much even with old orbit elements and the epoch of orbit elements does not have much influence on positioning errors. [ABSTRACT FROM AUTHOR]