Silencing radioheads

 作者:汤狄     |      日期:2019-03-06 06:16:04
By Barry Fox Loud music playing on a car radio can prevent drivers hearing the sirens of emergency vehicles. But Spanish inventors Javier Tester and Javier Cabrera have a neat answer (WO 01/45066). Ambulances and fire engines, they suggest, should send out a continuous radio signal at such low power that only cars in the immediate vicinity can pick it up; this could be the same signal that turns traffic lights green for them. Car radios that pick up the signals would automatically mute the music. This would alert the driver to the presence of an emergency vehicle,