From the national second-generation ID cards, the RFID application of the Shanghai Special Olympics, the Beijing Airport RFID baggage delivery system, the Guangzhou-Shenzhen Railway RFID ticket application to the Shenzhen Library RFID application, RFID has become ubiquitous. However, in the application process, RFID has encountered various degrees of setbacks. On December 7, the reporter interviewed Dr. Sima Cong, general manager of Asia Pacific of REVA, an RFID network application solution provider.
RFID is a technology that uses wireless methods for identity recognition. Its frustration comes from its particularity. Many bands can use RFID, but there are several major bands that can be used to standardize RFID in industrialization: 125 kHz in the low band, 13.56 MHz in the higher band, 433 megahertz band, UHF 800 In the megahertz-to-900 MHz frequency range, there are 2.4G and 5.8G frequency bands. In RFID applications, the 13.56 MHz frequency band applications account for more than half of the total annual business volume.
“This is the most common frequency band that is used by us. One-card and second-generation ID cards are in this band,†Sima Cong said. Because of the relatively short contact distance, people need to put their cards on the reader when boarding or leaving the bus. They will go to the airport to self-check the boarding pass and also need to attach the ID card to the automatic reading area of ​​the machine. The 13.56 MHz application is already very mature, and the UHF band has become a new challenge market.
Although the industry is generally optimistic that UHF RFID applications will increase to a considerable share, but in the promotion of many setbacks and challenges, mainly reflected in several major
aspect:
In the first aspect, according to different needs, RFID systems need different labels (encyclopedias) and different readers. Not only the product models, but also the manufacturers may not be the same. This requires that the application system must be a heterogeneous platform. The platform must have system integrators to integrate products from different vendors through a holistic solution. This is a big challenge.
In the second aspect, in the application of UHF band, the distance to read and write tags is relatively long, ranging from a few meters to several tens of meters. In more complex production environments such as supermarkets and warehouses, there are usually multiple antennas placed on the site. Which antenna is used in which frequency band? Which antenna signal does the tag receive? How to control it? Interference between the antennas may also occur. This is problematic. If these problems are not solved, it is impossible to accurately read the RFID data.
The third aspect is the requirement for time and deployment efficiency. The customer's requirements are very different. If you want to design RFID into a specific production environment, you need a process of deployment and on-site debugging. At the same time, you need to solve the problem very quickly. This contradiction also brings greater challenges.
In the fourth aspect, after getting RFID data, it also needs to be sent to the application. How can we make maximum use of it for such precious data? The experience of Wal-Mart is that after getting RFID data in the background, it first spread to 28 different applications. Therefore, the integration of data is also a complex challenge.
"An important feature of RFID is that each tag can only receive one signal at a time. If there are more transmitters, interference will occur. The tag does not know which signal to receive. Like a radio, it can only listen to one at a time. Frequency band." Sima Cong said.
In the face of these system engineering difficulties, REVA believes that networking is a good approach: put an intelligent network hub, according to the hub device to do optimal control of RFID antenna positioning, including optimal control of the band split, Optimal control of each antenna position optimizes all reader and antenna timings. This minimizes collisions and inefficiencies, making each reader's utilization highest in a complex environment.
REVA's network hub is called the TAP-tag acquisition processor. When a tag is detected by multiple antennas, TAP will perform logical calculations through various algorithms and then tell the user exactly where the tag was read. Accurate positioning of tags to solve the problem of mutual interference and crosstalk. Today, TAP is already compatible with dozens of RFID readers, which solves the problem of a heterogeneous platform. Sima Cong said.
At the same time, TAP supports all mainstream commercial software, including ERP software, or system software provided by companies such as Oracle, SAP, IBM, and Microsoft. If enterprise users need to develop their own applications, they can also use the development kit provided in TAP to correspond to each application software they have developed. This can also solve the problem of data integration.