Research Of Aircraft Communication Addressing And Reporting System And Fault Analysis

ACARS(Aircraft Communications Addressing and Reporting System) is an addressable digital datalink system for data exchange and information transfer between aircraft and ground stations via very high frequency equipment(VHF3), high frequency equipment(HF) or satellites. It is the ACARS who lets the aircrafts as mobile terminal connected to ground stations and improves abilities/capabilities of the airlines, air traffic controllers, aircraft manufactures and engine manufacturers to monitor and command the aircrafts. The ACARS plays such an important role in aircraft maintenance, airlines operation, and air traffic control that it is one of necessary avionics equipment for modern medium and larger passenger planes. The integrated ACARS system include airborne equipment, data service provider and ground station. Due to the late start of civil aircraft business in our country, research and design on ACARS is lagging. This paper introduced the ACARS operation principle, as well as two main protocols of ARINC618 and ARINC620 in details. According to traditional ACARS character-oriented operation features, this paper listed out three methods(fixed-format-method, Modular-format-method and eigenvalue-extraction-method) to decode the ACARS messages. Currently, civil aviation is facing seriously safety issues and airlines want to protect their trade secrets. This paper discussed the vulnerability of traditional ACARS communications in-depth, and the End-to-End architecture was presented, which employed message encryption and authentication to protect the information transferred between aircraft and airlines, thus the ACARS messages can be exchanged in a secure manner. Message encryption is extremely inefficient in terms of bandwidth conservation as it doubles the size of bit-oriented application data in the conversion process. So data compression algorithm is utilized to reduce message size and saves bandwidth(frequency resource). Also this data compression method is useful for traditional ACARS communication, which is compatible with new communication system.This paper gave some ACARS faults in China Eastern Airlines A320 fleet as an example, such as ACARS message discrepancy, the ground station fail in receiving aircraft messages, system clogging in short time and so on. The failure causes are summarized as hardware problems, software problems, line problems and personnel issues. At last, ACARS applications in our country and other leading countries were compared, further the future development of China’s civil aviation ACARS application were expected.