Research And Application Of MLAT System For Airport Surface Surveillance

The MLAT technology is proposed by foreign countries which can be applied to route, approach and airport surface surveillance. In GPS and GSM,the basic theory of MLAT has been widely used. In civil aviation, this system is used to detect the location of aircraft, vehicles and other mobile targets. The stations receive the ADS-B or Mode S/A/C message which are specific aviation format signals to obtain more information like S Mode address, flight No. and so on,rather than the location, and all these information would be send to the other ATC automatic systems like A-SMGCS.As the development of economy, the flight flow is increasing very fast, a lot of airports in our country are under construction for extension, but only several airports in our country are equipped with SMR,which can work without transponder on the aircraft, and is high reliable when the radar in good condition, but because SMR is primary radar, it is easily affected by the obstacle and the weather, and also can’t obtain more information by communication. The MLAT system can make up for this disadvantage, due to the low price of single station, we can easily increase the number of stations to compensate for the lack of blind area, generally speaking, we can expand the coverage and increase the accuracy by increasing the number of stations., and correlate the plot and tracks by using the information from transponder. In view of MLAT can provide the controller a safe and effective tool, MLAT become more and more popular in the airports. The purpose of this paper is to study the key facts which affect the system’s precision, discuss the basic principles we need to follow during the design of the MLAT system, and then we apply the conclusion to the design of Pudong airport MLAT system. And I hope this paper will also guide the design and construction of the MLAT systems in civil aviation in the future.The goal of this paper is to make the design of Pudong airport MLAT system meet the requirements, In this paper, we follow the three steps to analyze and solve the topic :Step 1: according to the basic theory of MLAT, analyze the factors would affect the system’s accuracy.Step 2: analyze the relationship between GDOP distribution and the site layout,make a conclusion about the rules needed to be followed.Step 3: with the conclusion in the preceding part of the article and the information from the site survey, we design the site layout of Pudong airport MLAT system to meet the system technical requirements, and then use simulator software to verify the design meets the coverage and accuracy requirements,and also is redundant,the whole system is reliable.