Research On Test Technology Of Transmission Characteristics In The AFDX Network

With the development of avionics technology, bus network becomes the nerve center ofthe avionics system, which has a very important position. At present, avionics data busbecomes increasing demanding for bus transmission characteirstics. In order to meet the highreal-time and deterministic requirements of aviation data bus, the bus transmissioncharacteirstics are gaining aviation indust’rys extensive attention.丁he network transmissioncharacteirstics test research contributes to understand and make better use of the network, aswell as provides certain reference value for the network performance evaluation.The main work and research results are summairzed as follows:Firstly，lacking of real-time and deterministic requirements of the Ethernet, and in orderto meet the requirements of aviation data bus, the AFDX (Avionics Full-Duplex SwitchedEthernet) network adopts key techniques that are fully different from Ethernet inimplementation, the real-time and deterministic requirements of the AFDX network isguaranteed fundamentally.Secondly, network transmission characteristics are deifned，and four importantparameters reflecting the transmission characteirstic are selected, those are throughput, packetloss rate, back to back, time delays. Then, the test principle of transmission characteirsticsparameters of AFDX network is analyzed in detail, as well as the related theory of testing andtest platform is introduced.Finally, based on the AFDX network，practical applications，single hop network andmulti-hop network is designed. As well as，the switch3nd end system conifguration table arerespectively formulated in detail. Then, the test program is developed based on the testplatform. With the deeply studied test methods of the various parameters, the AFDX networktransmission characteristics test is accomplished by these methods and the test data is collectedand analyzed.The results of all the parameters show that the AFDX network fiilly meets therequirements of high real-time and deterministic in aviation data bus. The AFDX network isthe best choice for the next-generation aviation data network.