Research And Design Of Key Technologies For TCAS Surveillance Functions

In order to ensure safe and orderly air plane flight, Air traffic control(ATC) systems should control and surveillance airspace flight. It is apparent that a single, ground-based air traffic control system cannot meet the requirements of all flight conditions, which requires another means to ensure air traffic safety, namely air traffic alert and collision avoidance system(TCAS). TCAS can achieve the information between aircrafts in vicinity,determining whether there will be a conflict or collision danger between the aircraft, to achieve the neighboring aircraft surveillance and collision avoidance.In this paper, the key technologies of the TCAS surveillance functions are studied and designed from the following some aspects:This paper researches the inquirer/response module,the interference limiting module and the tracking module of the TCAS surveillance functions. Firstly,introduce the TCASII system overalll software structure design, the mode C surveillance function model overall design, and the definition of main data structures.Mode C aircraft sends the whisper shout by through the inquirer interface function,and then,the target aircraft sends the message to the message queue after receving the inquirer,completing the exchange of information between the aircraft through the inquiry/ response module.Determining the target aircraft in threat, the aircraft should establish the track to surveillance the target aircraft. The paper researches the ATCRBS surveillance algorithms. As the aircraft equipped with altitude encoder and the aircraft without altitude encoder, they have different algorithms for track starting, track establishing and track updating, respectively. Thus, this paper presents responding surveillance algorithms in different situations.This paper mainly studies the high-density airspace surveillance.No matter between the aircraft and the aircraft or between the aircraft and the ATC, there exists the electromagnetic interference problems owing to the asked signal and the response pulse signal are overlapping. In order to solve a large number of interference problems in high-density airspace,This paper establishes mathematical model of the interference limit by the controlof transmitting power and tansmiting rate, completing the design of the interference limit in TCAS surveillance functions.This paper also conducts the functions testing and analysis of results for thesurveillance modules, determining whether the system function and performance could meet the requirements.