基于USB接口的AFDX网络TAP卡设计与实现

AFDX网络以其传输时间确定性、高可靠性和实时性等优点，成为新一代大型飞机航空总线的最佳选择之一。作为一种具有巨大应用潜力的新型的机载网络，AFDX网络的仿真测试至关重要。针对AFDX网络系统提出了一种TAP（test access point，测试访问接口）结构的测试卡设计方案。在设计的过程中，充分考虑了接入方式对网络传输的影响和数据捕获速率对主机接口的要求，采用串联植入方式设计出一款基于USB2.0接口的TAP卡及协议解析和数据统计软件，为AFDX网络的性能评估和系统级验证提供了方法和依据。通过在AFDX仿真验证平台中的实测结果，证明了该TAP卡具有灵活性强、测试精度高、实时性强等特点，完全满足AFDX网络测试及监控需求，为相关测试系统的研制提供了设计思路和实践经验。

Design and Implementation of the AFDX Test Access Point Card Based on USB Interface

AFDX network becomes one of the best choice for the next generation of large aircraft aviation bus,with its transmission time determinancy,high reliability and real-time.As a new type airborne bus has great application potential,AFDX network simulation test is essential.A test card design scheme of the TAP(test access point) structure is put forward for the AFDX network system.In the design process,the influence of the access to network transmission and the requirements of data capture rate of the host interface are fully considered,TAP card based on USB2.0 interface,and software of protocol analysis and data statistical are designed by using serial implant,the method and basis for the performance assessment and system-level verification of AFDX network are provided.Test results of simulation test platform for the AFDX show that the TAP card has characteristics of flexibility,high precision,strong real-time test,can fully meet the AFDX testing and monitoring requirements,the design ideas and practice experience are provided for the development of the related test system.