| 摘要 |
PROBLEM TO BE SOLVED: To provide an emergency vehicle alarm device that can determine a relation between an emergency vehicle and a one's own vehicle without complicated digital demodulation. SOLUTION: The emergency vehicle alarm device has a receiving means (antenna 11 and receiving part 12) for receiving a given radio wave, and a reception determining part 13 for determining a reception of the given radio wave. According to a reception signal and an S meter signal output from the receiving part, the reception determining part determines a reception of a positional information radio wave upon a reception of radio waves at constant intervals. The emergency vehicle alarm device further comprises a reception table 15 for storing a given number of pieces of time information and electric field strength information at the reception determination, a state determining part 16 for determining a relation (approach, separation or the like) between the emergency vehicle and the one's own vehicle from a history of the reception table, and an alarming part 14 for raising an alarm according to the output of either or both of the reception determining part and the state determining part. COPYRIGHT: (C)2004,JPO
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