Whether it’s for convenience features like adaptive cruise control, semi autonomous safety features like automatic braking, or for fully autonomous driving, more cars are being equipped with radar systems to detect other vehicles on the road. At some point, these systems could start to interfere with each other, like how the FM band in big cities is full of stations steping on each others’ broadcasts. While the only real consequence of that scenario is that there’s static on your favorite Wiz Khalifa song, when it comes to vehicle radar interference, the consequences could be dire—particularly if the car is relying on that radar to detect other vehicles and avoid crashing into them.
To prevent this, the FCC just vastly expanded its frequency allocations for vehicle radar, Reuters reports. This is the conclusion of a two-year process initiated by Bosch specifically for vehicle radar, according to the FCC Notice of Proposed Rulemaking. Originally limited to 76-77 GHz, the FCC’s ruling expands the vehicle radar allocation to 76-81 GHz, taking over frequencies allocated to radiolocation and amateur radio operators. According to the American Radio Relay League, amateur operations on the current 76-77 GHz vehicle radar frequencies had already been suspended pending verification that ham radio operators will not interfere with vehicle radar systems. It is probably safe to assume that this suspension will extend to the new vehicle radar frequencies, as well.
Similarly, vehicle radar needs its own frequency spectrum to ensure that it doesn’t interfere with other radio services. For example, the police would likely be unhappy if vehicle radar jammed their radar guns. As a bonus, this also means that vehicle radar will not set off your radar detector with false alerts since it operates on a completely different frequency than police radar.
Despite the loss of amateur radio frequencies (full disclosure: I am an amateur radio operator, so this affects me directly), the expanded vehicle radar frequencies are a good thing overall. This should ensure that there’s enough room for everyone to play as radar systems eventually find their way into all cars, and that these systems will not interfere with each other from car to car.