Chicago Transit Authority Gets Aboard the Wi-Fi Train

The nation’s second largest public transit system announced today that it has successfully deployed a solar-powered wireless mesh network in its rail yards. The Chicago Transit Authority (CTA) will use its new Wi-Fi network for mobile maintenance management. Planners expect the Tropos MetroMesh solution to increase productivity by shortening maintenance cycles through the introduction of paperless records transmitted over the high-speed wireless network.

The CTA’s system covers the City of Chicago and 40 surrounding suburbs. On week days, an average of 1.6 million rides are taken on its rails and roads.

The CTA WLAN covers 10 of its rail yards, the largest of which stores up to 282 railcars. Prior to the WLAN deployment, CTA rail car inspectors conducted manual inspections of train cars in the rail yards, reporting defects, taking mileage readings, etc. These tasks will now be automated using hand-held computers and the Wi-Fi mesh network. Inspectors can also scan each rail car number into the system before an inspection, improving accuracy.

SD∙I, a systems integrator specializing in fusing technical and operational support, worked with Tropos on the project, which began in early 2007. Among the challenges faced by SDI and Tropos in this environment, which was hostile to RF signals, were the metal rail cars themselves. The cars tended to reflect radio signals rather than allowing them to penetrate, resulting in signal distortion and a reduction in overall throughput. 

To solve the problem, Tropos used high-quality radios and its Predictive Wireless Routing Protocol (PWRP), which intelligently routes the Wi-Fi signal, in order to reduce data loss.

“The CTA recognized the need to design a solution that addressed its unique environment, yard-by-yard,” said Brian Diver, executive vice president of SD∙I. “Our experience with operations in non-traditional settings along with the performance and reliability of the Tropos mesh network, has resulted in a highly utilized and well-performing system.”

 Naomi Graychase is Managing Editor at Wi-FiPlanet.com

This article was first published on WiFiPlanet.com.