| 摘要 |
<P>PROBLEM TO BE SOLVED: To eliminate interference between interrogators installed on both the sides of a wall, in a passage management system, using the LF band and UHF band in combination, which is used for entry/exit control over a room, inventory control over articles, etc., and detects a transponder passing from one side to the other side across a wall by interrogators installed on the one side and the other side of the wall by making the interrogators generate an actuation signal of the LF band and making the transponder send back a response signal including identification information (ID) with a signal of the UHF band in response thereto using an internal battery as a power source. <P>SOLUTION: The interrogators 31 and 32 transmit the actuation signal through reciprocal operations (when one is ON, the other is off). Therefore, even when an inexpensive, easy-to-use radio wave system is used, interference between the interrogators installed on both the sides of the wall can be eliminated. Consequently, they can be installed nearby each other, and problems of routing of wiring with respect to construction can be made small. <P>COPYRIGHT: (C)2008,JPO&INPIT |
