The link between cars and consumer electronics may soon expand. A handful of automakers, chipmakers, and a Tier One supplier have formed a consortium that will promote the use of Ethernet in cars.
Broadcom Corp., NXP Semiconductors, Freescale Semiconductor, Harman International, BMW, and Hyundai Motor Co. teamed up to form a special interest group called the OPEN Alliance. OPEN, an acronym for One-Pair Ether-Net, is based on BroadR-Reach, a variant of Ethernet developed by Broadcom with input from consortium members.
BroadR-Reach provides bandwidth of 100 Mbits/s over an unshielded single twisted pair cable. The technology will initially be aimed at in-vehicle networks, where the high bandwidth and compatibility with consumer products will help the technology gain seats.
BroadR-Reach has the bandwidth to carry infotainment data as well as video, which is expected to gain acceptance as cameras are installed to give drivers a 360-degree view of the vehicle. The alternatives now being used for these types of in-vehicle networks don’t have the low cost and light weight of twisted pair copper wiring.
“This has a much lower cost of ownership as opposed to low-voltage differential signaling and MOST fiber-optic cable, which are larger and heavier,” said Rob Hoeben, Director of Ethernet Marketing and Business Development for NXP Semiconductors. He said NXP is the first chipmaker to license Broadcom’s technology.
BroadR-Reach also uses half the wires of other Ethernet variants such as Ethernet Audio Video Bridging. While the reduced weight and size of cables will help designers, the low cost of cabling and connectors are also attractive traits. The huge commercial volumes, which include many products ruggedized for industrial applications, provide high volumes.
Those volumes also mean that a large number of engineers and maintenance technicians will be familiar with the technology. Automotive Ethernet applications will most commonly use a switched architecture. This eliminates the likelihood of collisions, ensuring that packets will be delivered on time.
“Switches won’t be a dominant part of a system’s cost; you can go into Fry’s and buy a boxed switch for $20,” said Kevin Brown, Vice President & General Manager at Broadcom Corp. “Switches can provide some savings. You can bring data from different areas into the switch and then decide if you want to send packets out and where you want to send them.”
Installations should start showing up in cars around 2013, though proponents note that BMW began deploying Ethernet in 2007. Consortium members expect more companies to adopt the technology fairly soon.
Many automotive suppliers including Continental, Renesas, and Bosch have discussed plans to implement some version of Ethernet. Once Ethernet gains a foothold in cars, some proponents expect its usage to expand fairly rapidly.
“From an architectural perspective, there are many reasons that Ethernet can penetrate into the car,” said Ali Abaye, Senior Director of Product Marketing at Broadcom Corp. “Today there are islands of networks, cameras, infotainment, and body controls. Ethernet can collapse all those islands into one network.”
However, any possible changeover will happen slowly since automotive engineers are reluctant to fix proven technologies that are not broken. Some consortium members predict that if Ethernet expands beyond in-vehicle networking, its initial role will be as a backbone for communications between different modules.
“There’s already a hierarchy of networks in the car with LIN, CAN, and some FlexRay. I don’t see this replacing control networks,” said Peter Schulmeyer, Director of Strategy at Freescale Semiconductor’s Automotive Microcontroller Division. “As bandwidth requirements go up, I can see a main backbone going to Ethernet.”
Deploying Ethernet as a centralized backbone to carry signals between networks can bring benefits that begin when the vehicle is still in the factory.
“An Ethernet backbone could help with flashing and diagnostics,” Hoeben said. “When you’re downloading data, you need bandwidth. Right now, it takes around 45 minutes at the end of the production line to flash the software. Ethernet could shorten that significantly.”
Brown explained that the consortium’s roots began in 2007 when Freescale contacted Broadcom about the potential for using Ethernet in vehicles. BMW soon joined the duo as they worked on technology that would meet automotive requirements.