Channel capacity analysis for high speed controller area network (CAN)

Controller area network (CAN) is an in-vehicle communication network system. Many microcontrollers are built in vehicles that transmit and receive the data through CAN bus. As more microcontrollers are built in the car, the amount of data to be processed are increased. However, it is insufficient to process the increasing data because the maximum data rate of the standard CAN is 1Mbps. Therefore, we recently proposed a high data rate CAN system which combines the standard baseband CAN signal with a passband modulated signal. Before designing this system, the channel capacity analysis is needed to estimate the performance of the proposed scheme. This paper introduces the channel capacity analysis of the proposed scheme. In order to get the signal to noise power ratio (SNR) that is needed for capacity analysis, the standard baseband CAN noise is measured in a real car. Based on the SNR, water-filling algorithm is then employed for power allocation in the frequency domain, resulting in the channel capacity.