Page 412 - Understanding Automotive Electronics

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FUTURE AUTOMOTIVE ELECTRONIC SYSTEMS 11

collision with approaching vehicles (e.g., before lane changes are made).
Warnings to the driver can be made by synthesized voice or visual HUD
display.
Still another potential technical development in automotive electronics
involves the application of artificial intelligence to voice recognition. In such a
system the driver can activate electronic functions by simply speaking to the car.
A microphone will pick up his speech, recognize what is spoken, and take
action accordingly. Such a system has the advantage that the driver can enter
commands or data without looking away from the road while keeping both
hands safely on the steering wheel.
Another interesting technical development that is likely to occur in the
future involves the use of electronically controlled window transparency. Using
advanced electrochromic material it is possible to reduce window transparency
on very bright sunny days or to increase transparency on darker days. This has
the advantage of reducing glare and improving the heat load on the air
conditioning system within the vehicle.

OFFICE ON WHEELS
The development of cellular telephones for cars has greatly expanded the
ability to conduct business on the road. Not only is it possible to conduct
ordinary phone conversations while driving, but it is also now possible to
exchange information from home offices to the automobile via the cellular
phone. Since its introduction in 1984, the sale of cellular phones has increased
dramatically, with the total in service at roughly 4 million in mid-1991, and has
continued to expand exponentially since then.
A cellular phone is linked via radio to a two-way (duplex) fixed station
servicing a specific geographic region, or cell. The radio link carrier frequency is
sufficiently high that coverage for any cell is limited to the line of sight for the
fixed station antenna.
At the present time, cellular service is available within urban areas and
along high traffic interstate roads. As the car moves across the boundary of a cell
into another cell, a computer selects the particular cell for best coverage at each
location. Any cellular phone within a given cell can be connected to any phone
in the world using services of the cellular phone utility that operates that cell
and all fixed telephone utilities in the world.
Virtually any information service that is available in a fixed office through
telephones is now available in a car via the cellular phone. These extraordinary
capabilities have led to the term office on wheels for cars that are so equipped.
For example, a facsimile machine is readily operated through a cellular phone
link to any other facsimile machine.
In addition to facsimile machines, the office on wheels can readily
accommodate an answering machine and a portable computer with printer
and, of course e-mail. Clearly, the driver cannot simultaneously operate a

UNDERSTANDING AUTOMOTIVE ELECTRONICS 399