Reduction of Data Transmission Delay in Satellite-based ADS by Periodic Reporting Protocol

Abstract

Satellite data communications have been introduced in some areas to provide the means for message exchange between air traffic controller and pilot, and for aircraft surveillance in oceanic areas. Before the completion of the standards on aeronautical satellite data communications by the International Civil Aviation Organization (ICAO), we had conducted a series of flight experiments using INMARSAT satellites to validate the draft standards being developed by ICAO. The result showed that the T-channel data undergo a considerable amount of transmission delay due to its transmission protocol. This report describes a periodic reporting protocol for ADS report transmission to reduce the transmission delay and performances measured in laboratory experiments. The result showed, as an example, that the transmission delay decreases by about 7 seconds using the periodic reporting protocol compared to that of the conventional T-channel protocol at a channel rate of 600 bps.