| 摘要 |
<p>A transportation information warning system (10) for conveying traffic information from a traffic advisory site to a receiving station is disclosed. The traffic warning site comprises an emergency vehicle (12), a roadside hazard (14), or the like. The system comprises a transmitter (18) adapted for placement at the advisory site and a receiver (20) adapted for placement at the receiving station. The transmitter includes a first oscillator for transmitting a first unmodulated carrier signal at a first frequency and a second oscillator for transmitting a second unmodulated carrier signal at a second frequency. The first and second frequencies define the traffic information. The receiver includes a detector for detecting the first and second signals and an announcing device for announcing the traffic information.</p> |
