The present invention discloses a traffic caution apparatus which may distinguish
the running direction of vehicles. The apparatus includes a transmitter and a receiver.
The transmitter an ultrasonic transmitting unit and a FM stereo transmitting unit.
The receiver includes a FM stereo receiving unit, a decoding unit, an ultrasonic
receiving unit, a monolithic processor, an analogy switch, a speed recording/reproducing
unit, a given voltage unit. The apparatus uses ultrasonic wave to distinguish running
direction and speed of vehicles, and can send caution speech information with accuracy
to a vehicle whose speed must be limited. The apparatus has expandable function
which may provide other caution information, large number of travel and business
information to vehicles. This apparatus may substitute travel caution signs.
