Advanced system concepts for future civil aircraft-an overview of avionic architectures

The avionics systems of state-of-the-art commercial aircraft have become increasingly complex and sophisticated, in order to meet the ever increasing performance and reliability requirements. With the capability of the avionics technology improving by an order of magnitude every few years, it is envisaged that the current philosophy of one box-per-function will soon reach its limits in terms of cost, functionality, reliability, and certification. The proposed solution is the integrated systems configuration, using distributed processing, where the computational resources are shared between many functions, therefore improving the reliability, availability, survivability, and extensibility of the overall system. Furthermore, this approach will also provide the potential for reducing the acquisition, maintenance and operating costs. The paper discusses the limitations of the current avionic system’s architecture in deciding with the high levels of functionality required by the state-of-the-art aircraft, and discusses the philosophy of the integrated modular avionics, which represents a change in philosophy of avionics design to a decentralized, distributed architecture that allows interchangeable components within a distributed aircraft avionic system. The paper also addresses a number of specific issues considered necessary far the implementation of a decentralized, distributed architecture such as data bus requirements, electromagnet and radio frequency prevention, and fault quality features such as conformance, robustness, extendibility, compatibility, and re-usability built into the architecture