| 摘要 |
PROBLEM TO BE SOLVED: To provide a road traffic information reception device capable of consistently distinguishing between an express way and a general road.SOLUTION: In a road traffic information reception device having an air pressure sensor, a CPU performs: importing air pressure data A of the air pressure sensor when the CPU recognizes that a vehicle has come to a gateway area of an express way on the basis of the present positional information of a vehicle itself, the information received from a GPS module as well as expressway data stored on position registration data memory; importing air pressure data B when the CPU recognizes that the vehicle exit the gateway area of the express way; determining that the vehicle travels on an underground road if an absolute value of a difference B-A is equal to or larger than approximately 0.3 hectopascal and the difference has a positive sign, or that the vehicle travels on an elevated express way if the difference B-A has a negative sign; and determining that the vehicle travels on a general road if the absolute value of the difference B-A is less than approximately 0.3 hectopascal. Thus, the device can notify a driver of appropriate road traffic information such as a speed limit even when the express way and the general road run one above the other. |
