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The enormous increase of vehicle functions realized through electronic components significantly impacts the communication within the vehicle network. More functions are requesting higher bandwidth; safety applications require a deterministic communication scheme to ensure reliable system performance even under harsh real world conditions. The new FlexRay vehicle communication standard addresses these requirements, with production networks already on the road. The high transmission rate introduces new challenges for network developers dealing with the implementation of the electrical physical layer as the dynamic behavior of the system cannot be predicted using manual calculations. The FlexRay physical layer working group has therefore established a simulation task force dealing with issues related to FlexRay's physical layer implementation.

Future automotive applications, like high-speed control in power train or drive-by-wire systems, demand large bandwidth, deterministic communication behavior, and fault tolerance. FlexRay, a new standard communication system, is ideally suited to safety applications as well as applicable to the role of a central backbone in future ECU network architectures. The FlexRay physical layer specification is kept very generic to provide the network designer with a wide range of possibilities for optimization of the network implementation. Due to the highly transient behavior of the system, the developer of the network physical layer cannot manually predict the behavior of an entire FlexRay topology. To analyze design concepts like topologies, terminations, and ECU architectures much earlier in development phase, simulation is the only choice.

Electrical power requirements for vehicles continue to increase. Future vehicle applications require the development of reliable and robust power supply strategies that operate over various ambient temperatures and driving conditions. Insufficient charge balance is one of the major concerns for conventional lead-acid battery systems when operated with limited charging times during short journeys or extreme climate conditions. For vehicle power supply analysis, a detailed understanding of the operational characteristics of the major components and how they interact as a part of the electric power system, including environmental and road conditions, is essential if the analysis is to aid system optimization. This paper presents a model based technique that enhances the process of vehicle electrical power system design. Vehicle system optimization using virtual prototypes has become critically important as more electrical features are added to future vehicles.

FlexRay is an emerging communication technology used within Automotive In-Vehicle networking applications. However consideration of environmental variations, as well as device and overall system tolerances make development of a robust FlexRay network a daunting task. Even if the hardware prototype was available it may not be practical nor possible, to test and measure all the possible variations of network performance over this large multidimensional parameter space. But if simulation via a virtual hardware prototype accurately captured the FlexRay physical layer implementation concept, worst-case scenarios and corner cases could be efficiently investigated in face of any random or user selected combination of device and system variations. For simulation to be a viable option, the models for all the network components need to be available.

Due to the introduction of new safety and comfort systems in modern automobiles, stability of the vehicle electrical system is increasingly important. The increasing number of electrical components demands that additional electrical energy be provided from robust, reliable supply sources in vehicles. When designing such systems, simulation is the development tool that is used to quickly obtain information regarding electrical system stability, battery charge level, and the distribution of power to the consumer systems. This paper describes how the Saber simulation environment from Synopsys Corporation helps develop increasingly demanding and complex vehicle power systems. A Volkswagen vehicle power net serves as an illustration.

Due to the increase in demand for comfort and safety features in today's automobiles, the internal vehicle communication networks necessary to accommodate these features are very complex. These networks represent a heterogeneous architecture consisting of several ECUs exchanging information via bus systems such as CAN, LIN, MOST, or FlexRay buses. Development and verification of internal vehicle networks include multiple design layers. These layers are the logical layer represented by the software application, the associated data link layer, and the physical connection layer containing bus interfaces, wires, and termination. Verification of these systems in the early stages of the design process (before a physical network is available for testing) has become a critical need. As a result, the need to simulate these designs at all their levels of complexity has become critically important.