Ambulances in Stockholm are testing a system that interrupts in-car audio systems to warn drivers that they need to get through.
The solution was developed by students at the KTH Royal Institute of Technology in the city. It broadcasts a voice warning, while a text message also appears in the radio display. It uses an FM radio signal to jam drivers' speakers and stop music playing. It will only be able to alert cars that have their radios turned on. It can also interrupt CDs and music connected via Bluetooth.
[...] "Often drivers have only a few seconds to react and give way to emergency vehicles," said Mikael Erneberg, a KTH student who worked on the system. "The optimal warning time is at least 10 to 15 seconds."
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(Score: 2) by captain normal on Friday January 20 2017, @05:07PM
Seems like it is a bit more than sending a RDS alert. This device also blocks signals to speaker systems and from Bluetooth devices.
When life isn't going right, go left.
(Score: 3, Insightful) by yarp on Friday January 20 2017, @05:25PM
I think they do this with the Traffic Announcement feature of RDS. As long as the radio is tuned to a station it will interrupt other sources when a TA message is received.