Research on Modulation Technique of High Speed Loran-C Data Channel

At the age of global positioning system (GPS), Loran-C is still valuable. Loran-C can be used in the new navigation infrastructure both as a backup navigation and a redundant source of GPS integrity information which is provided by the wide area augmentation system (WAAS). The time information, such as WAAS message, can be added into Loran-C by using Loran-C data modulation. In this paper, several modulation techniques are discussed in detail. To meet WAAS message bandwidth requirements, on the base of Ninth Pulse Communication, we present a new hybrid modulation technique that can significantly increase the data rate of the Loran-C data channel.