Design Of Avionics Communication System Based On AFDX Technology

With the devolopment of communication, micoelectronic and network technology, the avionics system turns from genernal exchange of information toward a center of highly deepintegrated, ualtra high speed data connectivity system. In order to meet the avionics equipment demand of security, reliability, maintainability, high-bandwidth, the International organization defines the ARINC 664 standard. AFDX (avionics full duplex switched ethernet) has provided electrical and the agreement standard for data exchange, it profites from the ethernet mature technology, adaptes the aircraft-borne avionics system’s network detention determined, secure, reliable, the maintenance request.This paper introduces the development and research of avionics bus, describes the advantages of Ethernet technology and real-time capability, and the full-duplex exchange type ethernet’s concept. Combined with the development of Ethernet technology, we also analyses AFDX protocol , as well as its real-time realized method. Based on the analysis of the characteristics of the AFDX network, through building the end system and switchboard’s software and hardware platform, this paper has realized the avionics communication system based on AFDX technology.In the end system, virtual link management and redundancy management of AFDX Protocol are realized in FPGA. Through the PCI 9054, the host application software carrys on the data communication using the AFDX network card driver by the ARINC653 correspondence API. With the use of high-performance FPGA embedded MAC hard core, the communication speed between endsystem and switch can achieve wire-speed. This makes a hardware support for real-time design. In switchboard’s design, the method of designing the filtration, the management function, the exchange function, the monitoring function as well as the configuration files management are elaborated. In order to satisfy the real time request of AFDX, the flow control strategy uses the token-bucket algorithm, which guarantes that the data packet may not block the exchange.The result of analysis and test indicates that the designed AFDX network system can provide a greatly stable band width for the avionics communication system, enhance system’s communication performance.