ABSTRACT
This chapter focuses on the long communication systems used in civil aviation and analyzes the radio channel characteristics and modeling. It considers the different frequency bands and services used at present, as well as the future communication systems identified as potential candidates to be integrated into the future communication infrastructure foreseen to be operative for beyond 2020. Most options for on-board and external data communications offer limited capacity and versatility, thus explaining that the exchange of information is restricted to a limited volume of short messages with predetermined formats. The special history or legacy of aeronautical communications is responsible for the lack of rigorous, harmonized, and standardized radio characterization of the different frequency bands allocated for it. The modeling can be divided into two types of fading effects that characterize mobile communications: large-scale and small-scale fading effects.
