基于FlexRay总线的静态段带宽利用率研究

为提高FlexRay网络的带宽利用率,文中对FlexRay静态段参数和传输中消息的长度进行了研究。针对静态段参数数学模型和静态消息帧长度差异过大造成大量带宽浪费的情况,分别提出了MATLAB的优化函数和将部分较长消息分割成两个长度相同消息进行分配方法。文中阐述了将FlexRay静态段数学模型转化为非线性规划的问题,所提的分配方法考虑了分割后的消息在编码过程中增加的无效比特数对整个网络的影响。数值实验表明,该方法可以在理论最优带宽利用率的基础上实现进一步提高。

Research about Bandwidth Utilization of Static Segment Based on FlexRay Bus

In order to improve the bandwidth utilization ratio of the Flexray network, this study analyzed the static segment parameters of Flexray and the length of the message in transmission. To reduce the bandwidth waste resulting from the great difference between mathematical model and static message length, the optimization function of MATLAB and the method of dividing the long messages into two messages of the same length were proposed respectively. This paper illustrated the problem of converting mathematical model of static segment in Flexray network to nonlinear programming.The proposed distribution methods considered the effect of increasing useless bits in the coding process on the entire network. Numerical experiments showed that this method could be further improved based on theoretical maximum utilization of bandwidth.