In a world where people are increasingly impatient if an Internet page takes
too long to downloadtypically measured in seconds, but seeming
like minuteswhat 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.
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Interiors bristling with multiple flat panel displays may be commonplace within
a decade. But in order to bring the movie multiplex into the car, automakers will
have to implement high-speed multimedia networks like 1394, which has the bandwidth
to support several channels of streaming video.
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Already a leading standard in consumer electronics, 1394 is now almost ready
for prime time in vehicles. Its 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. Weve 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, 1394s 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. Visteons 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-Cs
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.
TIs 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. Were 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.