A Novel Algorithm of Time-Registration for 4D Trajectory based on GNSS´s time

Worldwide air traffic levels are growing at a rate expected to double the current traffic level. In order to control and ensure the aircrafts, most large airport surface have multi-sensors coverage, with not necessarily synchronized sensors, so a data fusion scheme is essential to provide a coherent and stable output. The multi-sensors include radars, VHF data link, and satellites, and form a surveillance network. The current technology air traffic control fusion systems are stretched to their limit and are prone to large delays during the peak summer travel season. There is doubt that the current systems can be scaled up to meet the expected demand levels and surveillance trajectory. Many air traffic management automation systems have been proposed to increase controller capability, and some are in operation. While ATM automation systems will help handle more traffic, it is still doubtful that they can grow to meet the doubling in traffic levels foreseen. In order to complete the function, the data come from the multi-sensors must be processed and then fused, so that the fusion trajectory comes into being. Fusion data come from PSR, SSR, ADS and VDL, time-scales are different. Before the 4D fusion trajectory comes into view, time-registration of the data must be implemented. Thereby registration is the vital problem for the data fusion of the multi-sensors network. This paper presents a novel algorithm of time-registration for 4D trajectory based on GNSS´s time for ATM. Because of the difference of surveillance data´s time-scales, general time-registration methods have many difficulties and risks for so many kind data. We find that there is connection between the surveillance data and GNSS´s time, so the data´s time-scales can be unified to GNSS´s time benchmark respectively, and then the unified data can be fused, the 4D fusion trajectory comes true. Using the GNSS´s time fusion systems can further improve the controller trajectory accuracy and can be used t- o increase airspace capacity