Replacement of the Controller Area Network (CAN) protocol for future automotive bus system solutions by substitution via optical networks

摘要

An automotive network needs to accumulate as much data as possible during motion to function in real-time, so that the system can respond to external influences accordingly. All kinds of situations regarding the state of the vehicle and its surroundings must be taken into account. To realize such a scenario many sensors, cameras and further input/output devices are essential to gather the required data accordingly. This means that the vehicle has to communicate with its environment such as buildings, road signs, traffic lights, other cars and so forth. The data has to be transferred to a central control unit, which processes all the incoming data to perform the next operation based on this data. Such deliberations lead to the backbone of such a system - the bus system, which connects all components within such a system. Currently, most of those parts are connected via a Controller Area Network (CAN) bus system or advancements of this system, which are mostly realized with copper cabling. The goal of this paper is to show the flaws of the CAN bus system for modern vehicle applications and to present a concept for a solution based on optical communications. With a single fibre optic cable it is possible to replace several cable harnesses and thus achieve remarkable weight and space savings. Due to the advantages of optical communications, a system with an appropriate network protocol will satisfy the intended requirements for higher bandwidths as well as secure data transmission and resistance to electromagnetic interferences, which pose a serious threat in modern automotive bus systems.