| 摘要 |
PURPOSE:To decide in which of a road side unit and a vehicle side unit the cause of communication error is present. CONSTITUTION:On the vehicle side, a receiving data is checked for CRC error (S19) and when the error 15 detected a plurality of times (S21, S22), a decision is made that the vehicle side down link is in a bad condition (S23). The CRC error check results are stored and transmitted to other road side unit pt the time of up link communication (S14) Consequently, the road side unit can detect a down link error of other road side unit based on that information. On the other hand, the fact whether a signal is received from a beacon through a communication link is stored (S23) and the fact is transmitted through up link communication (S14) thus detecting a failed road side unit based on the order of the link. Abnormality in the up link on the vehicle side can also be detected based on the fact that specific information can not be received (S26). |
