Architectures for next generation military avionics systems

Modular, open, integrated architecture has emerged as a key enabler of both military and commercial avionics suites that combine affordable cost with the ability to deal with rapidly changing technology and evolving system requirements. This paper describes recent advances in avionics architecture for military aircraft, using the evolving architecture of the Joint Strike Fighter (JSF) as a specific illustration. Key architectural attributes include effective implementation of open systems principles, hardware and software scaleability to cover a range of applications, independence of specific implementing hardware to minimize parts obsolescence problems, support for information security and trusted computing, and design features that facilitate integration and promote reliable and maintainable systems. A number of tradeoffs must be dealt with in optimizing such designs. These include choice of a fundamental interconnection fabric and interfaces, decisions on centralized vs. distributed processing, similar decisions on integrated vs. special purpose sensors and apertures, choices about the real time operating system and applications software, and a number of issues associated with mechanical and electrical design. The architecture must include robust testability features that ensure that the resulting system design can be tested and qualified to the criteria associated with avionics. The paper devotes special attention to the vexing problem of technology obsolescence and to the architectural approaches that can help to mitigate it.