Ethernet is coming to cars
- 22 October, 2014 04:01
One of the top microchip suppliers for the auto industry has announced its first automotive-grade Ethernet chipset and software, paving the way for car makers to install 100Mbps networks in vehicles.
The new processors from Freescale will connect in-car electronics and Wi-Fi routers over standard two-wire twisted pair cable, not CAT 5, making it robust enough to serve as a ring topology for vehicles.
A move toward Ethernet reflects the fact that in-vehicle electronics are becoming more sophisticated to support autonomous driving, exterior and interior cameras, embedded displays and infotainment systems.
By 2020, many cars will have 50 to 60 Ethernet ports and even entry-level vehicles will have 10, according to a study by research firm Frost & Sullivan. (Premium vehicles will likely have more than 100 Ethernet nodes by then.)
Other trends driving the need for Ethernet include connected cars -- vehicles that communicate with each other and outside infrastructure -- growing use of mobile devices and new driver-assistance technologies.
The growth in audio and video devices, such as federally mandated backup cameras, lane-departure warning systems, traffic light recognition and collision avoidance sensors, also all require more robust in-car networks. Ethernet's greater bandwidth could, for instance, provide a driver with turn-by-turn navigation while a front-seat passenger streams music from the Internet, and each backseat passenger watches streaming videos on separate displays.
Freescale's new AVB software stack
Along with the new hardware, Freescale has introduced an automotive-grade AVB (Audio Video Bridging) Ethernet software stack. The hardware/software combination supports a broad range of onboard multimedia nodes.
The Ethernet modules will also be embedded in telematics systems with 4G modems to connect the vehicle to the Internet, according to Dan Loop, Freescale's automotive business development manager. "What [automobile owners] can expect is a wider variety of multi-media systems in vehicles being deployed, allowing [car makers] to scale up easily," Loop said.
For example, Freescale's first module supports up to four synchronized video/audio streams for either embedded displays or mobile devices.
By using a ubiquitous standard like Ethernet, carmakers expect to save considerable money on hardware systems and cabling weight, according to Loop.
Need for standardization
Thilo Koslowski, Gartner's vice president of Industry Advisory Services for Automotive manufacturing, said Ethernet would bring standardization to an industry filled with proprietary data transport modes.
Even the most widely adopted high-speed transport specifications -- Media Oriented Systems Transport (MOST) -- contains a number of disparate protocols, depending on which automaker has deployed it.
MOST, as Ethernet will be, is a specification for transmitting data over a vehicle's controller area network (CAN). A CAN is a message-based protocol that allows microprocessors located throughout the vehicle to share data.
Currently, the CAN specification supports 500Kbps transport speeds, according to Nick Colella, Infotainment Manager for Ford.
Ford is considering using Ethernet as a "supplemental" data transport system, Colella said. The company uses other transport protocols, such as (Low-Voltage Differential Signaling (LVDS) in a small number of models. One issue is that a lot of video content still uses analog signals in vehicles, Colella said, so the move toward digital streaming could push the industry to Ethernet.
LVDS and MOST are also more expensive and complicated to roll out compared to Ethernet, according to Koslowski.
"Think about the ability to stream video content, which will be a big one. We just don't see that capacity in cars today because [data transport] systems are separate," Koslowski said.
Ethernet will join together all of a car's electronics systems, including the instrument cluster, the infotainment and the telematics systems.
Freescale's new hardware and software stack come under the SABRE (Smart Application Blueprint for Rapid Engineering) for Auto Infotainment (AI) development system.
The development kit for automakers is built on top of two of Freescale's existing i.MX 6Quad and i.MX 6DualLite applications processors. The Ethernet card supports Atheros Gb PHY (software compatible with CPU1 systems), a 10/100 Broadcom BroadR-Reach PHY and a 10/100 Broadcom BroadR-Reach 4-port switch.
Ethernet is not alone
There are upwards of nine competing standards to Ethernet for internal vehicle networking.
Other protocols, such as LVDS offers greater bandwidth -- up to 655Mbps today with rates of up to 3Gbps in the future being possible -- but its adoption and industry support pales in comparison to Ethernet.
LVDS signaling also uses external serializers and deserializers at each end of the link, which adds cost to any deployment, according to Loop.
Automotive-grade Ethernet has wide industry support via more than 200 members of the OPEN Alliance Special Interest Group, a non-profit established to drive adoption. Open Alliance members include General Motors, Ford, Daimler, Honda, Hyundai, BMW, Toyota, Volkswagen. Jaguar Land Rover, Renault and Volvo.
The recent formation of a new IEEE 802.3 study group to advance One Twisted Pair 100 Mbps Ethernet is expected to further drive adoption of the technology.
"As a proven technology with a vast ecosystem, Ethernet-based connectivity in automotive has enormous potential and based on how quickly membership has risen in the OPEN Alliance, the automotive industry is clearly enthusiastic," Natalie Wienckowski, General Motors' architect for electronics hardware, said in a statement.
Freescale is not the first chipmaker to announce an Ethernet solution.
For example, Paris-based Parrot, which supplies mobile accessories to automakers BMW, Hyundai and others, has developed in-car Ethernet. Its first Ethernet-connected systems could arrive as soon as 2015, says Eric Riyahi, executive vice president of global operations.
The BMW X5, released last year, used single-pair twisted wire, 100Mbps Ethernet to connect its driver-assistance cameras.
Parrot's new Ethernet-based Audio Video Bridging (AVB) technology uses Broadcom's BroadR-Reach automotive Ethernet controller chips.