Connected vehicle technology will enable dedicated short-range communication (DSRC) between vehicles (V2V) and between vehicles and infrastructure (V2I). The USDOT will likely require all new vehicles to incorporate DSRC capability by the end
of the decade. The penetration of this technology will take a number of years, so V2V benefits will be slow to emerge. However, every car equipped with DSRC immediately has the capability to communicate with roadway infrastructure, provided the infrastructure is equipped with DSRC. While NHTSA will coordinate V2V, it is up to states to respond to the V2I deployment opportunity.
There are at least two hurdles in the deployment path of V2I. First, the applications of V2I are just being tested. Second, the cost of implementing a V2I network to receive and compile vehicle data from the most heavily used parts of the US highway network will cost tens of billions of dollars.
Going back to the first point, the testing of V2I applications provides a role for some state DOTs. There are a few large DOTs with research capabilities and funding (for example, Virginia, Florida, Texas and California) to take on the V2I testing tasks. Other states, such as Michigan, are logical testbed sites due to the presence of auto makers. Unless a state wants to devote substantial resources to becoming a testbed site, it’s probably best to let the larger states take on the research task.
A positive interim investment is in traffic signals. Signals interconnected with fiber are already capable of being converted to a V2I device. Signal cabinets can be retrofitted with DSRC technology, and would have the ability to detect DSRC-equipped vehicles within 300m. When interconnected, as many signals already are, V2I technology could provide safety and efficiency benefits, helping drivers to better negotiate signalized arterials. However, the prudent current action is most likely limited to the continued interconnection of signals and to encouraging integration and management of signals across government boundaries. That activity would create immediate benefits for urban motorists, and prepare signal systems for ultimate DSRC benefits.
In terms of getting ready for V2I, a wholesale commitment to implementing the devices and network to manage data communications will not be a value-added investment until connected vehicle applications are better tested. Eventual deployment calls for roadside units to communicate with vehicles, all connected by a broadband network to assimilate information. What does make sense now, as mentioned in last issue’s column, is to expand the fiber network along major transportation corridors to become ready for connected vehicle data.
