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A novel approach to aviation data links and data exchange between aircraft modulesIlija Subotić, 2023
Abstract: Aviation industry is a key driver of global economic development with over a third of all trade by value sent by air. It represents a highly significant global market with estimated revenue over 840 billion USD in 2023, while the industry directly and indirectly supports an estimated $3.5 trillion (4.1%) of the world's gross domestic product (GDP) through the jobs and services of air industry suppliers, employee spending and serving industries such as tourism. Due to increasing global air passenger demand, the global aviation industry is projected to grow by approximately 25% from 2022 to 2027. However, in some cases the operation of aircraft may still be reliant on outdated technology that could be years or even decades old. Due to safety concerns, the global system of civil aviation is one of the most regulated industries, and every new procedure, technological advancement or device is required to be thoroughly checked by licensed institutions, numerous experts and aviation regulatory authorities. This reasonable approach inevitably leads to difficulties when dealing with noticed problems in any particular field – whether these are flight operations, aircraft maintenance, corporate affairs or general compliance. One of these problems are aircraft communications and data transfers between aircraft and all other groundbased stations. Namely, apart from classical radio links for voice communications, digital radio links for data transmissions have been used for a few decades now. These are ACARS (Aircraft Communications, Addressing and Reporting System) and CPDLC (Controller-Pilot Data Link Communications). These aeronautical communications data links use HF/VHF links and, alternatively, over areas with no or with poor signal coverage, commercial data satellites. However, there are several fundamental problems with data link systems implemented this way. The first problem is that the authenticity of the messages being exchanged cannot be verified. Potential attackers can, without much effort, falsify messages or even pose as a legitimate air traffic control unit or an aircraft crew. Another problem lies in the available bandwidth for VHF data links and the possible maximum transmission speeds reachable: the data transmission speed of VHF channels is very low - usually around 15 Kbit/s, and the best achievable results barely exceed 30 Kbit/s. In addition, the third major problem is message delivery, which is not guaranteed to succeed. There were indeed cases when the sent message did not reach the desired destination or arrived after a long delay of even several minutes. Aside from the mentioned problems, there are still issues related to specific aspects of the used HF/VHF data transmission links, such as signal stability, switching between individual ground radio stations, signal coverage issues etc. Therefore, in this dissertation, the main motive is to explore alternatives and find ways to solve at least some of these problems. The research in this dissertation is based on the usage of the Internet for the transmission of messages, instead of the previous radio data links. During the research it was concluded that the cellular Internet connection, even in today's technically inadequate state in the means of aeronautical needs, meets the conditions to be used as a medium for CPDLC and ACARS connections at flight altitudes up to 10,000 ft. Another goal of the research is to consider and develop the possibility of integrating the CPDLC and ACARS systems into one platform, codenamed IACARP (Integrated Aeronautical Communications, Addressing and Reporting Platform), which would provide the possibility to increase the number of functions and capabilities of both systems. The third intention of the dissertation is to propose and develop a dedicated communication protocol, which will be based on the Internet as a medium for data transmission, which will allow the IACARP platform to use a protocol that is adapted for use in aeronautical operations.
In addition to the communications protocol, the dissertation also provides a possible solution for the authentication problem of messages sent within the system, in a way that does not require encryption of those messages. The proposed solution represents a new algorithm for generating a special short code based on which the authenticity of the messages is confirmed. The possibilities of automatically sending individual reports from certain vital aircraft systems
to the air traffic control units are also being considered, through the proposed IACARP system. This way of integrating the components yielded another possibility which is thoroughly considered, and that is the remote control of the aircraft by ATC units in cases of emergency situations. Remote control of the aircraft in this way can most likely be achieved since there is a significant number of aircraft equipped with systems that can land them automatically, without much human intervention. Hence, it would be enough to just remotely reprogram the FMC (Flight Management Computer), enter a new flight route that would initiate landing at a suitable airport, as well as to remotely monitor and control the state of vital aircraft systems by giving the appropriate command through the IACARP platform. As the final part of the dissertation, the conclusions and the decision to accept or reject the hypotheses are presented, along with some perspectives and ideas for further research in this area.
Found in: osebi
Keywords: aeronautical data links, cellular networks, CPDLC, ACARS, air traffic control, message authentication, dedicated communications protocol
Published: 15.03.2024; Views: 208; Downloads: 7
Fulltext (13,29 MB)
