| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the following problem: when wireless communication is carried out between a vehicular key and a vehicle, and the owner of the vehicle, who holds the vehicular key and approaches the vehicle, locks/unlocks a vehicular door, if a distance between the key and the vehicle is determined based on the field intensity of electric waves, an area where the field intensity spatially drops exists, and therefore unstable operation occurs in the communication system. <P>SOLUTION: The communication system has a distance detecting means 211 for detecting the distance between the key 100 and the vehicle, based on a value of the electric field intensity; an authenticating means 202 for determining and authenticating a predetermined range where the vehicle exist 200, based on the distance; and a control means 209 for allowing control related to the vehicle after the authentication. If it is determined that the key 100 exists in the vicinity of the vehicle 200 by the authenticating means 202, detection by the distance detecting means 211 is disregarded over a predetermined time period after execution of the control by the control means 209. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
