Research On Low Altitude Flight Situation Awareness Technology Based On ADS-B

With the increasing of flight activities in China's low-altitude airspace and the gradual opening of low-altitude airspace,the Automatic Dependent Surveillance-Broadcast(ADS-B)technology has been widely used with the development and application of monitoring technology which used by navigation in the safe flight of low-altitude airspace.This thesis studies the main working of ADS-B system,focuses on the analysis of ADS-B IN technology,and then analyzes the standard message format of ADS-B and the main implementation process of CPR algorithm.The improved Residual-Mean Interacting Multiple Model(RMIMM)algorithm is used to filter the position state information of navigable aircraft and improve the accuracy of flight state estimation based on the decode of the key information data in ADS-B message.The improved algorithm is verified by the measured data received by the actual ADS-B device.Secondly,the Weighted Total Least Squares(WTLS)method combined with intention information model is used to improve the RMIMM algorithm with modified coordinate turn.The track prediction is realized by modifying the transfer probability of the model.The algorithm is verified by using the target three-dimensional position,flight status and other data received by ADS-B equipment.The results show that the improved algorithm has strong versatility,good prediction effect,and can accurately and quickly predict and track flight trajectory.Finally,the software of low-altitude airspace flight situation monitoring is designed by Android Studio platform.This thesis studies the software message protocol,studies the Bei Dou and ADS-B messages fusion technology,and takes Bei Dou communication as the supplement of ADS-B transmission link.The decoding of the ADS-B data is obtained through airborne terminal,and the display of analytic data is realized on the software.The experimental results show that the studied flight situation monitoring data package realizes the online situation awareness of low-altitude navigable aircraft by the ground surveillance center,and the designed software can display the flight track of navigable aircraft.The results of this research have certain significance for serving the operational safety of China's general aviation aircraft and the informatization level of low-altitude airspace management.