| 摘要 |
<p>Radio signals are filtered by an in-vehicle receiver to detect signals in a target frequency band from an emergency vehicle. A measured signal power or direction of the detected signals is compared to a threshold (Fig.5) to provide a warning indication. The warning may comprise multiple LED 4 wherein the number of illuminated LED indicates EV proximity. Alternatively visual 3 or audio 9 warnings may change colour, pitch or tone depending on separation between the EV and vehicle. Alternatively the warning may comprise mechanical indicators which rotate into view. The system may comprise multiple directional antennae 66,71,76,81 and the warning may indicate EV direction and position. To enhance visibility of the indicators, they may be shielded from direct sunlight in a recess (Fig.3). The system may comprise an integrated windscreen mount 13 with suckers and may be locked in place.</p> |
