Media Clock Recovery Over Ethernet Using IEEE 1722 on an FPGA

The rise of feature-rich smart vehicles has drastically increased the amount of required electronic control units (ECUs) in motor vehicles and, as a result, traditional wire harnesses for connecting up ECUs are becoming increasingly heavy and costly. Traditional intra-vehicle communication networks, such as the Controller Area Network (CAN), Local Area Interconnect (LIN) and Media Oriented Systems Transport (MOST) are being pushed to their limits. Multiple attempts have been made to improve these networks and their bandwidth, but this has caused a further increase in cost and complexity. Ethernet, a well-defined and popular standard that has high bandwidth, is being investigated as a means of replacing these traditional communication methods. IEEE 1722 provides a set of standards and methods by which time-sensitive data, a requirement for intra-vehicle communications, can be transmitted over Ethernet layer two. This paper presents, tests and verifies a design for the synchronisation of media clocks over Ethernet using the IEEE 1722 Clock Reference Format (CRF) on an Intel Cyclone V FPGA. The design was found to successfully synchronise two asynchronous 48 kHz clocks using packets transmitted through an Ethernet connection. This proof of concept shows that Ethernet can viably replace other intra-vehicle networks for transmission of time-sensitive information, helping alleviate cost and weight considerations while providing high bandwidth.