An Electronic Ear For A Brainy Highway System Of The Future

What do enemy submarines and thundering 18-wheel trucks have in common, besides scaring the wits out of the populace? Both can be monitored by an acoustic-detection system American Telephone & Telegraph Co. developed for the Navy. With the cold war over, AT&T is trying to sell a version of the sub-detection system to highway authorities for traffic control. This month, it began testing a production version of the SmartSonic Traffic Surveillance system on an entrance ramp of the New Jersey Turnpike.

The electronic ear doesn't bounce signals off objects, as sonar systems do. It just listens. It detects the same range of frequencies as a human ear, then uses artificial intelligence to figure out what kind of vehicle made them. Edward J. McKinney, head of AT&T's Federal Systems Custom Electronic Services unit, believes the ear will be able to distinguish all 13 categories of trucks, cars, and other vehicles that the Federal Highway Administration wants vehicle-identification systems to recognize. The data could be used to open special lanes, divert traffic, or limit access at entrance ramps, as a part of an intelligent-vehicle highway system.