| 摘要 |
PROBLEM TO BE SOLVED: To provide a radio tag system capable of suppressing power consumption of a wireless tag and shortening a period when the wireless tag cannot be positioned in a request cycle.SOLUTION: Communication between a tag and a reader is performed in the state that there are two wireless tags readers (readers) with which a wireless tag (tag) can communicate, and a reader distance L between the two readers and the tag is measured twice at a signal collection period interval. During the signal collection period, an acceleration signal of the tag is acquired and stored. When there are 3 readers which are communicable and three reader distances L can be measured, a position of the tag is measured (SC13), and a height difference H between a height in the measured three-dimensional position and a height of the reader is calculated (SC14). A horizontal direction position of the tag when measuring the reader distance is calculated according to the height difference H and the two reader distances L measured in advance (SC15). Correlation is determined according to the horizontal direction position and the acceleration signal acquired during the signal collection period (SC16). |
