Transit Wireless has been working with New York City's Metropolitan Transportation Authority to bring cellular service to 277 of the system's stations, and the company says it's on-track to bring service to 30 additional stations by the first quarter of 2013. The company says that it's still working on getting agreements with cell providers — it's locked in T-Mobile and AT&T — but is still in talks with Sprint and Verizon. The company says that carriers had to upgrade their backhaul to accomodate for underground use — it says customers use only 20 percent of voice traffic underground compared to an above-ground cell site, but 5 times more data. The expansion due early next year will bring wireless service to heavy traffic stations like Times Square, Columbus Circle, and Rockefeller center.

Cellular service began rolling out on the NYC subway system back in September of last year, but was only available in six underground stations. One of the big questions is whether cellular service will be provided in tunnels: while the contract only calls for service in stations, Transit Wireless says that it allows for expansion into tunnel coverage. The company says the service is being provided as part of a revenue-sharing partnership with the MTA, and that it's the only project of its kind in the United States