RFID belongs to wireless communication technology, which achieves non-contact identification through radio signals. Currently,
RFID is used for intelligent management in libraries
It has been widely used in China. According to the different working frequencies, library
RFID technology can be divided into two types: one is the mature high-frequency (HF) technology, and the other is the future trend ultra-high frequency (UHF) technology, each with its own advantages.
technical level
HF has a strong natural penetration ability, and it is basically unobstructed when facing other materials except for metal materials. Its operating frequency is also not restricted by radio frequency regulation. High frequency antennas are usually large in size and have short read and write distances. Observant readers will notice that the last page of a library book usually has a square label with a size of approximately 45mm x 45mm, which is a high-frequency electronic tag. In contrast, UHF is characterized by fast recognition and wide range, but when faced with substances such as liquids, metals, fog, and dust, ultra-high frequency signals can be severely interfered with. UHF tags have a small area and can be attached to the spine or crevices of book pages, making them more concealed.
Borrowing and returning books operation
UHF can borrow more than 10 books at a time, but the effect is not very good for more than 10 books. The inherent technical characteristics of ultra-high frequency make it easy to misread books from other readers around it onto the reader's account being operated. Therefore, an appropriate distance must be set between the two borrowing machines before operation can be carried out. However, HF requires that the labels of books should not be too close to each other, otherwise they will interfere with each other. At the same time, HF also requires a limit on the number of books borrowed at a time, which can easily lead to missed readings.
Book positioning and inventory
Books that have been listed and positioned can be displayed through a 3D navigation system, which requires library managers to list them in a timely and accurate manner. The positioning functions of ultra-high frequency and high frequency are the same, and their differences mainly lie in the reading distance and reading efficiency. By conducting inventory, information such as books being on shelves or misplaced can be obtained, and both HF and UHF can perform self-service inventory
The recognition distance of HF tags is relatively close, and during the scanning process, adjacent tags may be missed, affecting the inventory performance. If we want to improve the reading accuracy of HF tags, we can reduce the number of scans appropriately, but at the same time, it will slow down the reading speed. However, UHF tags have a relatively large range of reading distances, allowing them to quickly read ultra-high frequency tags. However, it is also possible to repeatedly read tags on adjacent bookshelves, which can affect the accuracy of inventory counting.
Book search, aging, and shelving
The operations of searching, removing old books, and flipping down books require pre setting the information of the books into the reader/writer before scanning can be performed. For books with HF tag scanning distance requirements that are relatively close and slightly farther apart, it is not easy to find them. In this regard, UHF is superior to HF. In addition, manufacturers of ultra-high frequency have developed "first book positioning" technology, which only needs to locate the position of the first book on the shelf, and even if the subsequent books change, they do not need to be repositioned.
Anti-theft security
For book security access control and theft prevention, both HF and UHF have blind spots, with built-in
RFID readers
Whether a book will sound an alarm normally when passing through a security door largely depends on the speed, shielding status, and location of the book. There are always some exceptions that can affect the anti-theft effect, such as placing books with HF tags and mobile phones together may cause the security door to not alarm, and holding books with UHF tags under the armpit through the security door may also not alarm.
Technical standardization
In order to achieve stability, security, and compatibility of library
RFID, it is necessary to standardize the use of technology. In terms of HF, the National Standards Organization (NISO) and the International Organization for Standardization (ISO) have already established relatively mature standardization systems in their early years. However, there is currently no unified standard for UHF internationally. In 2011, the "University Library
RFID Technology Application Alliance" was jointly initiated by Tsinghua University, Shanghai Jiao Tong University, and City University of Hong Kong Library to develop and establish corresponding standards for ultra-high frequency
RFID applications and technologies.
To sum up, both high frequency and ultra-high frequency have their own advantages and disadvantages. Ultra high frequency has significant advantages in terms of tag concealment and cost-effectiveness. In recent years, thanks to the support of the "
RFID Technology Application Alliance for University Libraries", many university libraries have chosen ultra-high frequency products. However, the mature application cases and market share of high-frequency
RFID make it have high conversion costs, and the possibility of being replaced by ultra-high frequency in the short term is unlikely. In fact, for libraries, regardless of the technology, what suits them is the most suitable. Libraries should select products and technologies based on their actual situation.
