| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an RFID reader for detecting elimination of merchandise or goods from a specific range in a display rack or the like in short time, and an inventory control system and an inventory control method using the RFID reader. <P>SOLUTION: Reading of IDs is totally conducted to RFID tags attached to merchandise existing in the specific range at a time t1 as indicated in fig. (d) using a method for preventing collision, and the IDs are recorded. As the third RFID tag is eliminated at a time t2, loss of the second RFID tag is detected without generating collision while requesting for response of each ID recorded. After a specific number of times of retry, it is fixed. Above procedures are conducted in shorter time compared to conventional methods (refer to fig. (b)) to conduct detection while preventing collision. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
