1090ES Automatic Dependant Surveillance-broadcast System’s Message Receiving And Parsing

With the improvement of the social and development of economic level, civil aviation’s need is growing day by day, which also contributes to the rapid development of civil aviation industry and the general aviation industry. The exiting of a large number of aircraft puts forword higher requirements for flight safety. To solve this problem, an important prerequisite is that aviation authorities should be able to keep abreast of the various aircraft air flight position and flight status, to ensure flight safety and effective.The main work of this thesis is to use the Automatic Dependent Surveillance‐Broadcast (ADS‐B) technology to receive and parse the aircraft’s flight status messages, and extract the meaningful data from the coded data of original data block, and thus provides data support for aircrafts status monitoring.Firstly, the theis studies the relevant technologies, including ADS‐B technology, data processing and multi‐threading technology. In the ADS‐B technology, the thesis focuses on the principle and data link of ADS‐B. In the data processing, the thesis describes cyclic redundancy check, LSB and MSB, data packing and unpacking. In multithreading technology, the theis describes four methods to achieve the thread mutex and synchronization.Secondly, the theis studies the structure and meaning of the ADS‐B related messages to define packet structure, the meaning and coding field of ADS‐B.Again, the thesis studies the receving and parsing of ADS‐B Messages. According to definition of ADS‐B message, the thesis analyzes the structural relationship between different messages, and then according to concepts analysis and business analysis in the business domain, the thesis designs ADS‐B message classes. Subsequently, the thesis defines the whole process from receiving initial data from the network to converting the data to ME messages. In order to facilitate the reuse and maintenance, the thesis designs a communication framework for ADS‐B message. The framework achieves the communication protocol setting, message data receving, message objects generating, and message subscribing and distributing. Finally, the thesis designs and implements a message reception and analysis software. The software designs include architecture design and functional design, which provide a layered software architecture and user functions of the software. Implementation of the software includes the selection of developing tools, the sturcture of codes and main codes of key features.