Vehicle-to-vehicle (V2V) communication provides proximity and basic status information to other vehicles utilizing the same technology, the purpose of which is warn drivers of impending collisions. Working alongside cameras, processors, interior sensors and other on-board safety and security features, V2V can dramatically increase system effectiveness by extending communication range with other vehicles and creating a true early-warning system.
It does the job using this basic example: Car #1 senses a problem, which automatically sends a signal to Car #2 to “brake now” which then triggers a signal to Car #3, and so on, avoiding multi-vehicle pileups on the expressway.
When V2V theory meets practice, we realize it is not so simple. Current DSRC technology is the preferred method of V2V communication and has similarities to 802.11a Wi-Fi which can be affected by multi-path and Doppler signal distortion, albeit to a lesser degree. And DSRC has range limitations, which would render it nearly useless in an emergency situation with no other vehicles within range.
Marrying V2V with vehicle-to-infrastructure (V2I) takes the range limitation of DSRC out of the equation. The concern now is of the network latency of cloud-based services. V2I signal transmission time from the sensor to the cloud and out to the next sensor of even 1 to 2 seconds can render collision avoidance systems almost unusable, particularly when a vehicle is traveling at highway speed. Network latency of 50ms to 100ms has been suggested as adequate, but that might not be possible using today’s V2I network technologies.
One solution would be the installation of signal receivers built along roadsides which, of course, would require a massive infrastructure investment that state and local governments under their current fiscal challenges are not likely to support. Is infrastructure privatization the answer? Maybe we should just let Google or Apple run the whole thing. They seem to be fairly well-capitalized.
Infrastructure arguments aside, another question: Is the integrity of the 5.9 GHz communication spectrum currently reserved for V2V communication being protected? Let’s make sure of it as we don’t want data-heavy, non-V2V traffic tying up the communication spectrum of an already time-critical service.
Source: Milliseconds Matter for Accidents – 360Here.com