LDACS1 conformance and compatibility assessment

In this paper the results of conformance and compatibility measurements of an L-band Digital Aeronautical Communication System Type 1 (LDACS1) transmitter are presented. The measurements were performed at the Institute of Electrodynamics, Microwave and Circuit Engineering (EMCE) of TU Vienna as well as in the labs of the German air navigation service provider Deutsche Flugsicherung GmbH (DFS) in connection with the SESAR project P15.2.4. Prior to the deployment of any new aviation communication system, the compatibility towards legacy systems has to be confirmed. For this purpose, an LDACS1 transmitter prototype was developed by Frequentis AG/TU Vienna to validate the LDACS1 system specification and prove the spectral compatibility of LDACS1 with the legacy L-band systems (e.g. DME, SSR, and UAT). Previous analysis has indicated that the DME/TACAN-LDACS coexistence is one of the most critical scenarios due to its wide and extensive use in the civil aviation.