Design Of Tcas Test System Based On CNI Architecture Software Radio Platform

Traffic Collision Avoidance System is a group of computer system carried by the medium and large aircraft,which is use to capture the information of aircraft in the surrounding airspace and forecast the possible collision of aircraft in the air.Most civil airplane are required to carried by TCAS,so the demand of TCAS test set is high.At present,only the equipment owned by Aeroflex company has passed the international certification,which occupy a monopoly position in the international market.We in urgent need of own intellectual property of TCAS test set to break monopoly of technology and fill the gap of domestic technology.So the research of TCAS test equipment has more important significance.Base on the architecture of CNI(communication,navigation,identification),a handheld TCAS test device is design by using the software radio technology.The main research contents are as follows:1.the development status of TCAS test device and the feature of software radio technology are analyzed,advantage and disadvantage of existing device in the world are summarized,and the design ideas of this subject is defined.On the premise of completion analyzing the core technology and principle of the system,base on the international standard of TCAS in civil aviation,the requirements test system are put forward by comparing with similar test equipment aboard.the preliminary design of test system framework are completed,and the FPGA+ARM7 universal hardware platform used in this test system is expounded,the function of three main modules of the platform: transceiver module,digital signal processing module,main control module is analyzed.2.This paper refer the data format standards and coding methods stipulated in international aviation convention,and the the coding and decoding software module are designed based on the idea of software radio.In order to meet the diverse test requirements,a dynamic simulation test method is put forward,which used the extended response signal to periodically update the longitude and latitude coordinate data to simulate the dynamic aircraft.Meanwhile,a control command frame with good security,usability,and high transmission efficiency is designed to realize the local control of function software.3.this project select the QT graphics development environment to design,which base on the object-oriented design concept and adhering to the principle of high cohesion and low coupling.The interface program is divided into data process module,interactive module,command communication module three modules for design,the design idea and realize method of three modules are describe detailedly.Compared with similar instruments in the world,the instrument design in this paper have more simple testing processes and has lower operate cost.Tester can use it without professional training.Finally,integrate and test the TCAS test system,use the special receiver to receive the signal send by the test system to verify the correctness of the system function.To ensure the accuracy of the system encoding and coding function.The signal sent by test system can be identified accurately by airborne TCAS equipment,and can simulate dynamic object flexibly,system can achieve the desired purpose.And the instrument is small in volume,easy to carry and operate,which can meet requirement of aircraft field test.