Afdx Bus Real-time Scheduling Algorithm Analysis And End System Research

With the development of the avionics technology, the requirement of the air bus is increasing so fast. The ARINC (Aeronautical Radio Incorporate)664standard, based on the IEEE802.3standard and the commercial COTS (Commercial Off the Shelf) technology, is issued by the avionics Technical Committee. And the newest air bus AFDX (Avionics Full Duplex Switched Ethernet), defined in the ARINC664, is applied on the Airbus A380successfully. Although the AFDX bus is used widely abroad, the research in our country is in its infancy.This paper is based on the avionics science fund project—ⅩⅩⅩ Ethernet research. It put importance on the real time analysis of AFDX bus. According to the delay distribution of the end-to-end delay model, the switch network and the End-system are the two key points in this paper. Because the AFDX bus network structure is very complex, it is necessary to build a simulation network model as the real situation, which is used to count the delay time from one point to another in some typical condition. From the point-to-point delay distribution results we can find a good way to reduce the switch network delay.Another focus of this paper is the research on the scheduling algorithms of the End-system.The improved SPTR(Static Priority Trigger Return) algorithm, which is based on the priority scheduling algorithm AVLSP(AFDX Virtual Link Static Priority) algorithm and PRTRG(Priority Real Time Scheduling Algorithm Based on Rate-Guarantee scheduling algorithm), is proposed to shorten the delay time of the End-system more efficiently. Besides, this paper realized the scheduling simulation platform of the SPTR algorithm by FPGA. This platform can be configured by the parameters to analog various real scenarios. Therefore, the performance of this algorithm can be analyzed in a realistic environment.