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In a world where people are increasingly impatient if an Internet page takes “too long” to download—typically measured in seconds, but seeming like minutes—what are the chances that automotive-based multimedia systems are going to be able to perform at anything less than blistering speeds? Not good. Which is why “broadband” capability is being developed for cars and trucks. Specifically, an open standard anemically designated “IEEE 1394.” Apple Computer, which developed the high-speed serial bus, has a better name for this technology with bandwidth to burn: “FireWire.”
Already a leading standard in consumer electronics, 1394 is now almost ready for prime time in vehicles. It’s ability to simultaneously stream multiple channel of audio and high-quality video make it the technology that can transform vehicles into the multi-screened rolling entertainment centers envisioned in many concept cars. And work is underway to make it practical for the demanding automotive environment.
Automotive 1394 proponents know that the baseline standards developed for consumer electronics must be significantly modified to meet automotive requirements. So in January 2000, an automotive working group was formed between the 1394 Trade Association and the IDB Forum, which resulted two years later in the IDB 1394 standard for automotive. IDB 1394 specifies an automotive-grade physical layer that includes new plastic fiber optic cable and connectors, as well as a new power management scheme designed to preserve the integrity of vehicle batteries. Based on this work, Texas Instruments (TI; Dallas, TX), Renault, and the French software company Mindready produced an automotive reference platform designed to catalyze 1394 development. “We’ve provided it to most major OEMs and Tier 1 suppliers to help them cut down on the amount of time it takes to research 1394, and to show them the breadth of what the technology can do,” says Brad Little, automotive business development manager at TI.
According to Little, the biggest advantage of 1394 is its bandwidth. The fastest current automotive multimedia network operates at a signaling rate less than 50 Mbits/sec. Whereas the initial implementation of 1394 transfers data at 100 Mbits/sec., an expanded version will bump the rate up to 200 Mbits/sec. And the physical components of the system are specified for a 400 Mbit/sec. to accommodate future growth without changing hardware. Pom Malhotra, program manager at AMI-C (Automotive Multimedia Interface Collaboration*), which is tasked with setting common multimedia standards, puts the bandwidth numbers in perspective this way, “Basic command and control functions need less than 1 Mbit/sec. For audio streaming you need at least 10, low-quality video needs 20 to 50, and 50 and higher is for high quality video. If you are going to do DVD-quality video, then you are going to need the higher bandwidth.” In addition to video for entertainment, 1394’s high signaling rate can accommodate video from collision avoidance systems that needs to stay uncompressed to avoid compromising signal integrity. Other advantages include a network topology that facilitates the addition of a variety of OEM and aftermarket devices without having to cut fiber cables, and the fact that 1394-based systems are already well-established in the consumer electronics market, which could reduce compatibility problems if users want to plug-and-play their own hardware.
The question remains: how much bandwidth do you really need in a vehicle? Many in the automotive industry think that the 1394 rival MOST (Media Oriented Systems Transport), which has a 24 Mbit/sec. capacity, can meet automotive multimedia needs for years to come. “1394 can handle many, many channels of audio or video, but how many do you need running around in the car?” queries Dr. Robert W. Schumacher, business line executive, Wireless and Mobile MultiMedia for Delphi. Visteon’s Director of Electronics Product Development, Martin Thoone, adds, “People are pragmatic. MOST can do the job in automotive, so why do you need something else?” MOST certainly has a lot going for it. It is strongly backed by automakers like Mercedes and BMW; it was developed specifically for automotive applications, and perhaps most importantly it is already in several cars today. MOST developers are also working on versions that would boost signal rates to 150 Mbit/sec. to defuse the bandwidth issue. (It should also be noted that the two standards can co-exist on the same vehicle, and automakers are developing systems that utilize both.)
Still, 1394 may be the technology of choice within a few years. AMI-C’s Malhotra says, “When we have discussions about future technology roadmaps with OEMs and suppliers, the general consensus is that 1394 seems to have a longer technology road map since it goes into higher and higher bandwidths.” TI’s Little, who as the former chairman of the IEEE 1394 Automotive Working Group is not exactly a disinterested party, sees MOST not as competition but as a precursor and “launching pad” for 1394. He says, “I think we will see 1394 being implemented in some of the European platforms where they will have MOST on the embedded side of the network and gateway over to 1394 or have an accompanying 1394 network just for video. We’re seeing a big push there.” Malhotra says that this kind of interest in 1394 is being driven by market-specific requirements like streaming DVD-quality video. “I see the strongest interest for 1394 coming out of Japan and Europe and a passive interest on the part of the North American automotive manufacturers,” he says.
1394 should start showing up in production vehicles in 2006, but according to Little it will be available in the aftermarket later this year. As for which automaker will debut the technology, Malhotra says, “Renault is a very serious contender for taking 1394 into production. And there is also a lot of effort from the Japanese automakers.” Little will only acknowledge that Renault is the farthest along “publicly,” and hints that far more 1394 work is being done quietly in R&D centers than is readily apparent. If so, it may be that more people are beginning to think that too much is just enough.
*AMI-C OEM members include Ford, Fiat, GM, Renault, Honda, Toyota, Nissan, and PSA Peugeot Citröen.