RFID Application In Retail

- Nov 23, 2018-

The unmanned supermarket, this hot word that has gradually surpassed the "shared bicycle" in the near future, has become a bright spot in front of everyone. Alibaba's trader Ma Yun recently proposed the concept of “new retail”, arguing that retail stores in the form of supermarkets and convenience stores can reach “unmanned supermarkets” without the help of cashiers. Along with the emergence of unmanned supermarkets near the parking lot of the Changshang Road store in Shanghai Yangpu District, Binguo Box, Rosen, Alibaba... Many companies announced that they will open or open the “unmanned supermarket” project. In Shanghai, this new business has quietly landed.

International giant Amazon acquired offline retail supermarkets (acquisition of US Whole Foods Supermarket for US$13.7 billion) to stimulate the traditional hypermarket tycoon Wal-Mart (the stock price reflects a 7% decline in the day trading), before the end of last year, it rushed to the offline retail segmentation scene, released A four-year super big move - the new offline store Amazon Go. Stores that do not need to check in at the checkout: brush the phone into the store, select the product, get the goods, and then leave! Amazon's unmanned supermarkets are eye-opening, don't line up and don't checkout, take things and leave, Amazon Go shopping is almost in one go.

The success of Amazon Go has naturally spurred giant companies such as Alibaba. Through cooperation with high-tech companies, major companies have gradually made the new retail concept of unmanned supermarkets a reality. The emergence of unmanned supermarkets and RFID The use of technology is inextricably linked. According to the experience of local users in Shanghai, the products in the unmanned supermarkets were labeled as a label.

This kind of label is an electronic label and an important part of the RFID system. The supermarket uses the omnidirectional label H47 in the inlay series. The label uses the latest true 3D technology from impinj. The H47 uses the label dual antenna to read the effect. Unrestricted by the reader antenna, it can be well recognized in space 360 degrees, and is a major innovative technology in the field of UHF RFID. The electronic tag combines with the reading and writing system in the automatic cash register to help consumers complete the payment.

As a wireless communication technology, RFID technology is very suitable for the concept of new retail. Therefore, it is understandable to make RFID technology the hero behind the unmanned supermarket. In the case of combining RFID-related technologies, unmanned supermarkets also combine technologies such as electronic surveillance to make a truly unmanned supermarket as perfect as possible. Perhaps the birth of an unmanned supermarket will be like sharing a bicycle. There are many problems that need to be solved, but a more convenient economic lifestyle has become an era trend.

For an RFID system, its frequency band concept refers to the frequency range of the tag signal that the reader sends, receives, and reads through the antenna. From the application concept, the operating frequency of the radio frequency tag is also the operating frequency of the radio frequency identification system, which directly determines various aspects of the system application. In an RFID system, the system works just like we usually listen to FM radio, and the RF tags and readers have to be modulated to the same frequency to work.

The working frequency of the radio frequency tag not only determines the working principle of the radio frequency identification system (inductive coupling or electromagnetic coupling), but also determines the distance and the difficulty of implementing the radio frequency tag and the reader. The frequency bands or frequencies occupied by RFID applications are internationally recognized as being located in the ISM band. Typical operating frequencies are: 125 kHz, 133 kHz, 13.56 MHz, 27.12 MHz, 433 MHz, 902 MHz to 928 MHz, 2.45 GHz, 5.8 GHz, and the like.

Depending on the operating frequency, RFID tags can be classified into low frequency (LF), high frequency (HF), ultra high frequency (UHF) and microwave. The working principle of RFID in different frequency bands is different. RFID tags in LF and HF bands generally adopt the principle of electromagnetic coupling, while RFID in UHF and microwave bands generally adopt the principle of electromagnetic emission. At present, the frequency widely used in the world is distributed in four kinds of bands, low frequency (125KHz), high frequency (13.54MHz), ultra high frequency (850MHz ~ 910MFz) and microwave (2.45GHz). Each frequency has its own characteristics and is used in different fields, so to use it properly, you must first select the appropriate frequency.

The low-frequency radio frequency tag, referred to as the low-frequency tag, has an operating frequency range of 30 kHz to 300 kHz. Typical operating frequencies are 125KHz and 133KHz. The low frequency tag is typically a passive tag whose operating energy is obtained by inductive coupling from the near field of the radiation of the reader coupling coil. When transmitting data between the low frequency tag and the reader, the low frequency tag needs to be located in the near field region radiated by the reader antenna. The reading distance of the low frequency tag is generally less than 1 meter. Typical applications for low frequency tags are: animal identification, container identification, tool identification, electronic latching theft (car keys with built-in transponders).

The operating frequency of the mid-high frequency band RF tag is generally 3MHz ~ 30MHz. The typical operating frequency is 13.56 MHz. The RF tag in this band, because its working principle is exactly the same as the low-frequency tag, that is, it works by inductive coupling, so it should be classified as a low-frequency tag. On the other hand, according to the general division of the radio frequency, its operating frequency band is also called high frequency, so it is often referred to as a high frequency tag. Since the RF tag in this band may be the largest RF tag in practical applications, we only need to understand the high and low understanding as a relative concept, that is, it will not cause confusion. For ease of description, we refer to it as an IF RF tag. The IF tag is also generally a passive setter. The working energy is the same as the low frequency tag. It is also obtained by the inductive (magnetic) coupling from the near field of the coupled coil of the reader. When the tag is exchanged with the reader, the tag must be located in the near field of the reader antenna radiation. The reading distance of the IF tag is generally less than 1 meter. Because the IF tag can be easily formed into a card shape, it is widely used in electronic tickets, electronic ID cards, electronic lockout anti-theft (electronic remote control door lock controller), residential property management, building access control systems, etc.

The radio frequency tags in the UHF and microwave bands are referred to as microwave radio frequency tags. The typical operating frequencies are 433.92 MHz, 862 (902) MHz to 928 MHz, 2.45 GHz, and 5.8 GHz. Microwave radio frequency tags can be classified into active tags and passive tags. In operation, the RF tag is located in the far field of the radiation field of the reader antenna, and the coupling between the tag and the reader is electromagnetic coupling. The reader antenna radiation field provides RF energy to the passive tag and wakes up the active tag. The reading distance of the corresponding RFID system is generally greater than 1 m, typically 4 m to 6 m, and the maximum is more than 10 m. The reader antennas are generally directional antennas, and only the radio frequency tags within the directional beam range of the reader antenna can be read/written. Due to the increase of the reading distance, it is possible to have multiple RF tags in the reading area at the same time, which raises the need for simultaneous reading of multiple tags. At present, advanced RFID systems regard multi-label reading problems as an important feature of the system. UHF tags are mainly used for automatic identification of railway vehicles, container identification, and can also be used in road vehicle identification and automatic toll collection systems.

At the current state of the art, relatively successful products of passive microwave radio frequency tags are relatively concentrated in the operating frequency band of 902 MHz to 928 MHz. 2.45 GHz and 5.8 GHz RFID systems are mostly available with semi-passive microwave RF tags. Semi-passive tags are typically powered by button batteries and have a farther reading distance. The typical characteristics of microwave radio frequency tags mainly focus on whether passive, wireless read/write distance, whether to support multi-tag reading and writing, whether it is suitable for high-speed identification applications, the transmit power tolerance of readers, the price of radio frequency tags and readers, etc. . For wirelessly writeable RF tags, the write distance is usually less than the read distance because the write requires more energy. The data storage capacity of microwave radio frequency tags is generally limited to 2Kbits. The large storage capacity does not seem to have much significance. From the perspective of technology and application, microwave radio frequency tags are not suitable as carriers for large amounts of data. Their main function lies in Identify the item and complete the contactless identification process. Typical data capacity indicators are: 1Kbits, 128Bits, 64Bits, etc. The product electronic code EPC set by the Auto-ID Center has a capacity of 90 Bits. Typical applications for microwave radio frequency tags include mobile vehicle identification, electronic latching theft (electronic remote door lock controller), medical research and other industries.

Labels with different frequencies have different characteristics. For example, low-frequency tags are cheaper than UHF tags, save energy, penetrate through scrap metal objects, and work frequency is not subject to radio frequency control. It is most suitable for objects with high water content. For example, fruits and the like; ultra-high frequency has a wide range of effects, and the data transmission speed is fast, but it is relatively energy-consuming, the penetration is weak, and the working area cannot have too much interference, and is suitable for monitoring items in the logistics fields such as ports and warehouses; The frequency tag belongs to the medium and short distance identification, the reading and writing speed is also in the middle, and the product price is relatively cheap, such as application on the electronic ticket card.

At present, different countries use different frequencies for the same band. The UHF used in Europe is 868MHz, and the U.S. is 915MHz. Japan is currently not allowed to use UHF in RF technology.

Currently in practical applications, the commonly used frequency bands are 13.56MHz, 860MHz ~ 960MHz, 2.45GHz. The short-range RFID system mainly uses LF and HF frequency bands such as 125KHz and 13.56MHz, and the technology is the most mature; the long-distance RFID system mainly uses UHF frequency bands such as 433MHz, 860MHz to 960MHz, and microwave frequency bands such as 2.45GHz and 5.8GHz, and is still testing more. Among them, there is no large-scale application.

China's technology in the design of RFID tag chips in the LF and HF bands is relatively mature. The design technology of the HF band is close to the international advanced level. The RFID chips conforming to ISO14443 Type A, Type B and ISO15693 standards have been independently developed and successfully applied. Traffic card and second-generation ID card and other projects.

Analysis of RFID related patents across the Taiwan Straits

In the process of research and practice of RFID systems, intellectual property issues will inevitably be encountered. On the one hand, the corresponding patents and intellectual property reflect the current research level and provide reference and reference for practice; on the other hand, through the analysis of related patents and intellectual property rights, it can provide new directions and ideas for further research. Here, only the RFID-related patents on both sides of the Taiwan Straits are taken as an example.

There are a large number of RFID-related patents on both sides of the strait, which involve all aspects of the RFID system chain. We take the patent situation of the two sides from 1996 to June 2004 to analyze the development of RFID, and point out that it is reflected from the patent level. The issues that need to be focused on development and resolution.

Taiwan RFID related patent search

Taiwan has 28 related patents during the period from 1996 to June 2004, involving labeling, readers, antennas, system information processing methods, network applications and system applications.

Among them, the readers accounted for 6 items, the label category - including its production, manufacturing, packaging, application design and invention accounted for 12 items, antenna class 1 system, system method class 2, RFID system application class 5, anti- Collision 2 items.

Mainland RFID related patents

During the period from 1996 to June 2004, the mainland had 106 patents related to labels, readers, antennas, information processing, network applications, information processing and system applications.

Among them, the readers accounted for 18 items, the label category (including its production, manufacturing, packaging, application design and invention) accounted for 53 items, the antenna category 6 items, the RFID system application and method category accounted for 18 items, and the collision prevention 2 items. The mainland has nine patents in network applications and information processing.

Through analysis, it is known that RFID and related patents in mainland China and Taiwan mainly focus on label design, manufacturing and packaging, etc., followed by readers, including their circuit design and some closed-loop systems using RFID, or some simple applications; The software components of the chain, such as information processing combined with the network, large-scale open-loop applications and some key issues such as anti-collision problems, and barcode compatibility issues are rarely patented. Even RFID application patents are generally simple examples of RFID applications, and do not form a system on a large system. In addition, there are few related intellectual property rights and patent applications in the whole background processing, database management, coding rules, scheduling problems, etc. of RFID, and there is relatively less intellectual property in the testing strategy of RFID applications. This is critical for the wider use of RFID. In the future, our research direction can propose a complete set of solutions and frameworks in combination with large system applications, and at the same time study the construction of an effective network-based background information processing system. In addition, some key issues in the practical application of RFID technology are also the direction we should jointly study, such as anti-collision problems, electromagnetic compatibility problems and so on.

Unmanned supermarkets also made RFID glow for the second spring. The unmanned stores based on RFID technology currently have the following three modes, which are mainly divided into:

1. Pre-identification (identity) mode

2, free identification (identity) mode

3, full open mode

The pre-identification (identity) mode means that the user needs to identify the product before opening the smart goods cabinet or the door of the unmanned store, and then the product can be purchased. For example, the unmanned shop introduced by Auchan first needs to scan the QR code (identity authentication) before entering, which belongs to a typical pre-identification (identity) application. If the identification cannot be completed, the consumer cannot make a shopping action! Both are equipped with RFID tags and form corresponding electronic bills).

The identity-free (identity) mode means that the user can purchase the product without identification. Generally, such unmanned shops will have an access control system. Consumers can directly enter the store through physical switches. After the consumer enters, the access control is automatically locked. After the purchase is completed and the payment is successful, the access control can be reopened. (Products are equipped with RFID tags and form corresponding electronic bills).

The full open mode means that users can enter and exit the store freely, and they can freely choose products. The products are provided with RFID and QR code payment labels. Consumers can choose to store the products and scan the code to complete the payment. However, if the store is not completed, the access control system will automatically detect and report the alarm. The advantage of the full open mode is that it can solve the multi-point shopping settlement problem, and the store transformation is relatively controllable. This mode, if equipped with a small number of service personnel and combined with the application mode of the first two modes, is particularly suitable for a new mode of convenience store and supermarket to form a combination of people and unmanned applications.

Regardless of whether the unmanned supermarket is successful in this business model, but RFID has become a popular thing.