Concern Mounts over 5.9 GHz Band Spectrum Sharing, Future of Connected Vehicle Program

Federal Communications Commission Chair Julius Genachowski announced earlier this month that the commission is seeking to "unleash" the 5.9 GHz band in order to "increase speeds and alleviate Wi-Fi congestion at major hubs, such as airports, convention centers, and large conference gatherings." However, doing so may interfere with the connected vehicle program, which is designed to use that frequency.

Currently, the U.S. Department of Transportation is testing connected vehicle technology, which is a multimodal initiative that will allow for wireless communications between vehicles, transportation infrastructure, and passenger communication devices. While still in early phases, proponents believe the technology will greatly increase safety (through vehicle crash prevention applications), improve mobility (by allowing drivers to make choices that reduce delays), and improve the environment (through less wasted fuel).

The connected vehicle program relies on the 5.9GHz band spectrum to transmit the messages that provide key safety information on vehicle position, speed, weather, road conditions, and traffic signal timing. Transportation experts argue that any interference from unlicensed stations using the same frequencies will impact the ability of other stations to receive and decode those vital messages, as well as the amount of time a vehicle or operator will have to react to those changes.

The University of Michigan's Transportation Research Institute (UMTRI) last August began a year-long road test of about 3,000 vehicles in Ann Arbor equipped with the connected vehicle technology (see related AASHTO Journal story: bit.ly/AJconnectedvehicles). The test is the second phase of the U.S. Department of Transportation's Safety Pilot, the largest road test ever for connected vehicle crash avoidance technology. The information collected during this test will be used along with other information to determine whether the National Highway Traffic Safety Administration will move forward with additional connected vehicle activities, including rulemaking.

"The American Association of State Highway and Transportation Officials supports the initiative to increase the availability of technology increasing the amount of information to the public," said AASHTO Executive Director John Horsley. "However, without these particular frequencies being available for traffic safety, it is feared an opportunity and investment in connected vehicle technology will be forever lost."

Those sentiments were seconded by other transportation agencies.

"We understand and support the effort by the FCC and the National Telecommunications & Information Administration to identify spectrum that may be utilized to ease the broadband shortage resulting from the proliferation of wireless services and devices," said Scott Belcher, president and CEO of the Intelligent Transportation Society of America. "We recognize that sharing within the 5.9 GHz band should be explored. However, policymakers should be mindful not to fast track a decision without a complete record and fair opportunity for all affected parties to participate in the process, particularly when life-saving vehicle technologies are on the line."

More information on the connected vehicle program is available at bit.ly/NHTSAcv.