分布式航空电子系统信息传输机构设计研究

THE DESIGN AND STUDY OF THE INFORMATION TRANSFER MECHANISM FOR A DISTRIBUTED AVIONICS SYSTEM

航空电子系统日益增长的复杂性使其必须走向分布式处理的道路。本文介绍一个基于1553B总线的分布式航空电子系统的实验模型——EPDAS系统,讨论了EPDAS系统信息传输机构的有关组成部分:总线通信协议、通信管理软件和总线接口,本文在分析传统的同步总线控制方式的缺点之后,提出了询问和命令/响应相结合的总线控制方式,该方式能提高总线传输的效率和实时性。在EPDAS系统的总线接口设计中,引入了流水线并行处理技术,解决了总线接口的瓶颈问题,并使之易于VLSI化;伪DMA控制的概念,使总线接口电路更加简化;共享存贮器的互连技术,具有效率高、控制简单、容易实现等优点。EPDAS系统结构合理、效率高,符合国情、适合于新一代的飞机。

The growing complexity of avionics systems has led it to distributed processing. This paper introduces an 1553B based on Experimental Prototype of Distributed Avionics System(EPDAS) , and discusses its related components of the information transfer mechanism, such as the protocol of the bus communication, the communication program and the Bus Interface Unit(BIU) .After having analyzed the shortcoming of the conventional Synchronous Bus Control strategy, this paper presents a bus control strategy of PCCR (Polling Combined with Command/Respones) , which can raise the efficiency of bus data transfer.The adoption of pipeline processing in the BIU design for the EPDAS system makes the BIU not only faster but also simplified so as to be suitable for VLSI implementation.The concept of Pseudo-DMA Control, proposed in the paper, further simplifies the hardware of the BIU. The efficient interconnection via shared memory between the BIU and its host computer is easy to control and implement.