| 摘要 |
PROBLEM TO BE SOLVED: To provide an inter-vehicle distance measurement device which can measure an inter-vehicle distance by using inter-vehicle communication while suppressing communication load.SOLUTION: If an inter-vehicle distance measuring device detects that it has reached a specified point on a road (S2:YES), it transmits by broadcasting a dedicated packet SP indicating the fact thereof (S4) and stores time Twhen it reached the specified point and the speed of an own vehicle Vat that time in a storage unit (S6). After storing them, when the dedicated packet SP is received from a succeeding vehicle (S8:YES), it stores the time of the reception Tand the speed of the own vehicle V(S10). Then, an inter-vehicle distance D between the own vehicle and the other vehicle is calculated as the product of time difference (T-T) from the time Twhen the own vehicle reached the specified point and the average speed of the own vehicle (V+V)/2 from the time when the own vehicle reached the specified point to the time when the dedicated packet SP is received from the other vehicle (S12). |
