A Book Auto Inventory Method Design And Implementation Based On Variation Of RSSI In RFID Library

As the RFID technology is using more and more deeply in the areas of library, the services such as book positioning, rapid self-serve book borrow and return are began to face to the readers. In these services the book positioning is the most import one to the readers, for it greatly shortens the time they used to find the book. To achieve this, the library must have an accurate data of every book’s information. Nowadays, these RFID libraries are using an easy way to do the book positioning. They associate the book RFID tag with the book shelf layer RFID tag, these bookshelf layer tag is the projection of the real bookshelf into the cyberspace. The regularly book inventory can make the data of library more accuracy. However, the present situation in library still leads a lot of labor to do the book inventory.This paper presents a new auto book inventory algorithm which based on the variation of the RFID tag’s RSSI. This technology doesn’t need the help from workers and it can work without the connection between it and the database. The base of this algorithm is a simple theory, the RSSI of the books on the A side will be changed greatly than the books on the B side when the antenna of RFID reader scan the RFID tag in the A side of the bookshelf. To make the discrete data points to be comparable, curve fitting method is involved to change these points to a continuous curve function. The cluster on the parameter which presents the curve can differentiate between the RFID tag in A side and the RFID tag in B side. At last a sort by the peak time of the curve function can make the book tags be classified to the bookshelf layer tag which belong these books.At the last of this paper, we implement a prototype system which based on this algorithm. And the performance shows this algorithm is truly applicable on the real library environment, and it still need some more research to do to make it works more reliability.The main work and contribution of this paper concludes:1. Review the existing work about the principle of RFID system and RFID tag scanning, especially some method relate with the RFID library.2. Discuss the challenges in the automatic book inventory in RFID library scenario. Some influence factors such as the read range, robot speed and number of RFID tag reads are tested in some experiments.3. Proposed an automatic book inventory method which is based on RSSI value variation of RFID tag in the RFID library. Curve fitting method and clustering then are applied on the RFID tags’ RSSI values to distinguish the RFID tag on the different side of the book shelf.4. Implement a prototype of RFID library, the algorithm designed before were implemented, work and analyzed in this RFID library.