| 摘要 |
PROBLEM TO BE SOLVED: To prevent communication performed using a predetermined frequency from being disturbed by the frequency dispersion of switching noise while a switching noise source is driven. SOLUTION: In the case that a collation condition is satisfied to perform collation through weak radio communication between an in-vehicle unit and a portable unit, a predetermined frequency is used to execute the weak communication for the collation. At the same time, during vehicle ignition-on, switching noise caused by driving a power device including a frequency slightly deviated from the predetermined frequency is frequency-dispersed over a wide band, thereby reducing a peak level of the switching noise. In the case that a collation condition is slatisfied to perform collation through weak radio communication between the in-vehicle unit and the portable unit, on the other hand, the frequency dispersion of the switching noise is stopped (step 106). COPYRIGHT: (C)2009,JPO&INPIT
|
