| 摘要 |
<P>PROBLEM TO BE SOLVED: To confirm a circuit condition and an operation state by simple operation from an antenna side in an on-vehicle unit of an antenna separation type used for DSRC (dedicated short range communication). <P>SOLUTION: The on-vehicle unit used for the DSRC is composed of a main part (2), an antenna (3), and a coaxial cable (4) connecting the both. The antenna is provided with a parallel connection circuit of an antenna circuit (5), a two terminal resistor circuit network (6) whose resistance value between two terminals changes when an operation switch (SW1) is operated, and a light emitting element (D1) between the internal conductor (4a) and the external conductor (4b) of the coaxial cable. The main part is provided with an operation state detection means which detects the state of the operation switch from the change of the direct current resistor value of the parallel connection circuit seen from the main part side through the coaxial cable, and a signal processing means. When the operation of the operation switch is detected, the circuit condition and the operation state are diagnosed, and reported by a voice. <P>COPYRIGHT: (C)2007,JPO&INPIT |
