FlexRay™ electrical physical layer: Theory, components and examples

Modern passenger cars are no longer imaginable without using technologies to broadcast local acquired data. The vehicle speed for example is used by many well-known functions: the anti-blocking system, the radio, the dash board, the cruise control, the electronic stability program etc. Usually these local acquired data is distributed among vehicle´s electronic control units by various electrical serial communication systems. The paper introduces one of their newest designs named FlexRay™. The development of FlexRay™ began in the early nineties of the last century driven by the requirements expected for drive-by-wire systems. The referenced section focuses on the FlexRay™ electrical physical layer; it can be seen as evolution of the widely-used CAN electrical physical layer. This electrical physical layer evolution had been driven mainly by one kernel requirement: enabling a tenfold maximal communication speed. The broad range from topologies and hardware components up to simulation approaches is covered. Selected comparisons between CAN and FlexRay™ support the comprehensibility of the indicated evolution approach.