The capacity and performance of a CPDLC system using VDL mode E

VDL mode E is a digital TDMA communications system proposed as a global standard for replacement of the 8.33 kHz and 25 kHz analog AM systems currently used for VHF aeronautical communications. VDL mode E is spectrum compatible with 8.33 kHz analog channels, providing an orderly phased-in upgrade of either 8.33 kHz or 25 kHz systems to provide increased channel capacity and security for both voice and data link communications. With air traffic communications migrating to data link systems, such as the VDL mode 2 link 2000+ CPDLC network in Europe, it is important that any new system provide adequate performance and capacity for this type of communications. The paper provides an overview of the design and estimation of capacity of a proposed data link configuration of VDL mode E optimized for CPDLC operation. It shows that the capacity provided exceeds that needed to support the forecasted levels of European air traffic through the year 2050.