An overview of current and proposed communication standards for large deployment of Unmanned Aircraft Systems

Current public, private, and military communication systems, like conventional terrestrial and satellite phone data communication systems, have never been designed to provide connectivity to Unmanned Aircraft Systems (UASs) in very large numbers. UASs need not only to communicate, but require ubiquitous coverage and secure data links by design, catapulting them to the forefront of demanding communication systems. It is shown that current communication systems are neither designed, nor capable to handle the assumed growth of Unmanned Aircraft (UA) and that their routing, security, data rate, and range are not optimized for UAS flight characteristics. Ideas for upgrading current communication systems to better suit the communication needs of UAS are researched. Yet, it is argued that new communication standards are necessary, to not only cover singular and localized use cases of UASs, but enable global networking benefits. The paper gives an overview of the communication standards in development and their focus area selected by their standardization bodies. The standards are investigated regarding whether they sufficiently address the needs arising from the predicted numbers of UA and are suited to enable a broad set of use cases. In particular, the new proposed schemes are examined on the physical (PHY) and medium access (MAC) layers. It is differentiated between communication for Command and Control (C2), also termed Control and Non-payload Communication (CNPC) in IEEE and ITU, communication for cooperative surveillance, and payload communication. These separate needs of information transmission have different requirements, but combining them into a joint design has technological and economical benefits. New proposals for routing algorithms are surveyed and categorized, emphasizing on Mobile Ad-hoc Networks (MANETs), Vehicular Ad-hoc Networks (VANETs) and their relation to Flying Ad-hoc Networks (FANETs). These networks are primary means for establishing connectivity between UAs, but also between UAs and ground stations. Because of the enormous amount of routing protocols and proposals, there is no desire to offer a complete list, but to give a comprehensive overview over the most suitable algorithms taking the unique UAS requirements into account.