The Research Of Technology Of AFTN Telegraph Auto-processing System

AFTN telegraph automatic process system is important component of air traffic control automatic system. It is responsible for sending the flight plan and dynamics, and helping the controller to keep the flight safe.Research work is based on introducing communication network of telegraph in civil aviation and its recent development. Advantages and disadvantages of software based on B/S and C/S structure were highlighted. According to the characteristics of telegraph automatic processing system, C/S mode was adopted as the framework. Main contents studied in this paper are as follows.(1) String was segmented and matched in processing of telegraph message. Matching and processing of telegraph message were accomplished after telegraph marshalling is defined by regular expression,at the same time divide-and-conquer method was adopted for separating strings. The most obvious advantages is that once telegraph structure was changed, it is not necessary to change original code, but only to change regular expression which defined telegraph structure when the system was maintained.(2)To realize automation of telegraph processing, backtracking algorithm was used to process and update telegraph record real-timely.(3) Based on building database of airplane performance and air routes, the telegraph sending module was developed, correct rate of telegraph sending was improved and controller's workload and human errors were reduced.(4)The article employed a method that the sender adopted fixed format of telegraph sending and the receiver used error tolerance to process telegraph message, and the correct rate of receiving message was improved.The telegraph automatic processing system based on the research results has been applied in the air traffic control. Identification rate was increased significantly. Because of the messy code caused by transmitting of telegraph signal and informal telegraph sending and some other unpredictable reasons, it is very hard to identify and process telegraph completely. Error tolerance algorithm was used in the system, but it still needs to be modified.