Unveiling the Future of Vehicle Networks: Optical Fiber vs. Copper Cables
Carlos Pardo from KDPOF discusses why plastic optical fiber (POF) is better than copper for car data networks.
Studies and market research predict that advanced driver-assistance systems (ADAS) will become essential in vehicles, linking various electronic systems. These systems need high-speed networks, often requiring speeds of one gigabit and beyond. Choosing the right physical layer for future in-car data networks is crucial because it affects both cost and weight, which are key factors in modern car design.
Traditionally, car networks have relied on optical or copper-based physical layers. Copper comes in different forms like unshielded twisted pair (UTP), shielded twisted pair (STP), and coaxial cables. Although copper is the default choice due to the risks of adopting new technologies, it has several drawbacks: it’s heavy, costly, and vulnerable to electromagnetic interference.
Cost, Electromagnetic Compatibility, and Weight
Plastic optical fiber (POF) addresses these issues effectively. It supports gigabit speeds, is low-cost, and has already been qualified for use in data transmission. It’s cheaper than shielded twisted pair (STP) cables and costs about the same as coaxial cables. POF costs are also more predictable compared to copper. Moreover, POF is immune to electrical noise, unlike UTP, and its plastic composition makes it much lighter. It’s also durable, withstanding harsh conditions like engine compartment temperatures up to +105˚C. POF’s strong bending performance begins at a 10mm radius, and it allows gigabit transmission over distances up to 50 meters.
Flexibility and Reliability
POF systems are proven in the automotive sector and are used in various communication standards like Flexray, Byteflight, and Most. This results in a wide range of compliant devices and suppliers. Manufacturing and installing POF is simple and doesn’t require special equipment or changes to existing processes. POF can handle high bandwidth demands from video-based sensors, making it ideal for applications like high-definition rearview cameras, 360˚ view systems, parking assistance, wing mirror replacement, backseat monitoring, and night vision.
Standardization
POF gigabit technology has been standardized by VDE-DKE in Germany, ETSI, and most recently by the IEEE with the 802.3bv standard for gigabit Ethernet over POF. This standard, known as 1000baseRH, outlines specifications for automotive, industrial, and home networking. According to the IEEE, POF is particularly useful for applications where long link lengths aren’t necessary, providing a reliable media option for Ethernet automotive networks. The technology is also being standardized globally through the ISO.
Overall, plastic optical fiber presents a compelling alternative to copper, offering benefits in cost, weight, durability, and immunity to electrical noise, making it an excellent choice for future automotive networks.
