WiMAX helping drivers see through the fog

Editor's note: This is the third installment in a series of stories that will appear periodically in FierceBroadbandWireless highlighting the deployment of wireless broadband in rural communities. Click here for "Sacred Wind: Bringing WiMAX to the Navajo reservation [1]"; and check out "Georgia citizens take broadband into their own hands [2]."

For the locals who regularly drive on California State Route (SR) 99 in [3]the San Joaquin Valley, tule fog--that extremely dense ground fog named after the tule grass wetlands in the California Central Valley that blankets the highway from November to March--is a normal part of life. And that's a problem.

Tule fog is unpredictable and can suddenly reduce effective visibility to zero so that driver can't see more than five feet in front of their cars. When visibility is low, drivers are complacent and don't adjust their speed, but transportation authorities in California have a unique tool to combat the complacency: a WiMAX network.

After an 86-vehicle chain-reaction accident outside of Fresno in November 2007  killed two people and injured 41, the California Department of Transportation (CALTRANS) and the California Highway Patrol (CHP) deployed a WiMAX system. The system, which was deployed earlier this year, provides drivers with real-time speed and visibility information, giving them the opportunity to adjust their speed accordingly.
Jose Camarena, chief public information officer with the CHIP District 6, said the stretch of SR 99 that typically has the worst tule fog has existing signs with warnings, but that wasn't enough [4]for people who were used to seeing the signs every day as they traveled through one of California's major north-south arteries. Transportation officials needed something that was "in your face," Camarena said.

"After our last very ugly accident, the local community as well as the Sacramento office said: 'What can we do to get people to slow down?' We needed to convince people to realize that in dense fog you can't drive 80 MPH. They may be very familiar with their route, but when visibility goes down to 20 to 50 feet, they don't adjust their speed," Camarena said. "Most of the time people who have been involved in accidents are locals."

So with $12 million from CALTRANS, the CHP's District 6 deployed the "Fog Pilot" along a 12-mile section of SR 99. The unlicensed WiMAX system includes an impressive plethora of technologies: weather detection stations... continued [5]