VOIP in ATC communications — Where are we today

Under the auspices of Eurocae WG-67 industry and global Air Traffic Navigation Service Providers have collectively developed a set of standards, which look promising for global implementation in ATC. This paper provides a compact description of the main notions of the recommendations developed in Eurocae WG-67. Results of interoperability testing and field trials within operational environments conducted in the first half of 2009 are discussed demonstrating the applicability of SIP and RTP protocols to ATC communications. Industry (radio and voice communication systems) and major air traffic navigation service providers (ANSPs) agreed on field trial testing of IP based equipment with the aim to allow for a seamless airspace that is managed flexibly within dynamic airspace blocks. The paper describes selected radio practices and outlines associated requirements for absolute and relative delay as well as minimal end-to-end data rates of ground-to-air transmission compared to results from those field-trials.