Search This Supplers Products:RFID ReadersBarcode ScannersMobile ComputersRFID BarCode Solutions
Do you know the history and current situation of RFID?
The history and current status of RFID
RFID is the abbreviation of Radio Frequency Identification (RFID) technology. It is a non-contact automatic identification technology developed based on radar technology. Compared with other automatic identification technologies, such as barcodes, optical identification and biometric identification technologies, it has the advantages of strong anti-interference ability, large amount of information, non-visual range reading and writing, and long life. It is widely used in fields such as logistics, supply chain, animal and vehicle identification, access control systems, library management, automatic toll collection and production and manufacturing.
In 1948, Harry Stockman published the article "Communication using Reflected Power", which laid the theoretical foundation of RFID. Over the past half century, the development of RFID technology has gone through the following stages:
From 1941 to 1950, RFID technology came into being with the improvement of radar. The application of radar in 1948 laid a theoretical foundation for RFID technology.
From 1951 to 1960, RFID technology was still in its early exploration stage and was mainly conducted in laboratory research. Its related theories and technologies were not yet mature.
From 1961 to 1970, the theory of RFID technology developed to a certain extent, and some application attempts began. For example, the first commercial example of RFID technology worldwide was the use of electronic anti-theft devices (EAS) to deal with thieves in shopping malls. This anti-theft device uses an electronic tag with only 1 bit of storage capacity to indicate whether the product has been sold. This electronic tag is not only cheap, but also can effectively prevent theft.
From 1971 to 1980, RFID technology and product research and development were in a period of great development, and various RFID technologies and tests were accelerated. In terms of industrial automation and animal tracking, some of the earliest commercial applications and standards have emerged, such as industrial production automation, animal identification, and vehicle tracking.
From 1981 to 1990, RFID technology and products entered the commercial application stage and began to be used on a large scale. However, different countries have different focuses on the application of radio frequency identification technology. The United States focuses on traffic management and personnel control, while Europe mainly focuses on animal identification and applications in industry and commerce.
From 1991 to 2000, the number of manufacturers and applications using RFID technology increased day by day, and mutual compatibility and connectivity became the bottleneck that plagued the development of RFID technology. Therefore, the standardization issue of RFID technology has attracted increasing attention. It is hoped that through a globally unified RFID standard, radio frequency identification products will be more widely used and become an important part of people's lives.
RFID technology products and applications entered a stage of rapid development after 1990. The American TI (Texas Instruments) began to become a pioneer in RFID and established the Texas Instruments Registration and Identification System (TIRIS). Currently known as TI-RFIS (Texas Instruments Radio Frequency Identification System), this is a major platform for RFID application development.
In 1991, the world's first open highway electronic toll collection system was established in Oklahoma, USA. The vehicle's RFID electronic tag information is bound to the detection point location information and the car owner's bank card, and stored in a computer database. The car can pass through the toll detection point at high speed, and the fee can be automatically deducted from the car owner's bank card, and there is no need to set up lifting railings to block or cameras to capture the license plate.
Lufthansa uses contactless radio frequency cards as air tickets, changing the traditional way of purchasing and selling air tickets and simplifying airport security procedures.
In China, the city of Shanghai has installed an automatic road maintenance toll collection system based on RFID technology. Guangzhou and Foshan have applied RFID systems to open highways to automatically charge high-speed vehicles to improve vehicle passing efficiency and alleviate highway bottlenecks.
In the mid-1990s, the Automatic Railway Identification System (ATIS) built by the Ministry of Railways of China used RFID technology to realize [automatic copying of train numbers for trucks]. Ground identification equipment (AEI) is installed at all section stations, marshalling stations, large freight stations and boundary stations to accurately identify running trains and vehicle information. On this basis, a computer automatic report collection system was established to store information such as railway train numbers, locomotive and freight car numbers, identification, attributes and locations. Real-time and autonomous statistics of railway vehicle management systems have been realized, becoming one of the most typical applications of RFID technology. Especially since high-speed railway trains began to operate, it is particularly necessary to use RFID technology for automatic, fast, and efficient management to reduce the probability of train accidents.
In 1999, the Auto-ID Center of the Massachusetts Institute of Technology formally proposed the concept of Electronic Product Code (EPC). The combination of the concept of EPC, RFID technology and Internet technology will build a ubiquitous Internet of Things. Especially in recent years, IBM has proposed the concept of smart earth. After being affirmed by President Obama, the concept attracted widespread attention around the world.
After 2001, the variety of RFID products has become more abundant, and standardization issues have attracted more and more attention. The application scale of the industry continues to expand, active tags, passive tags and semi-passive tags have all been developed, and the cost of tags continues to decrease. Wal-Mart, the world's number one retailer, announced the widespread use of RFID and the U.S. military announced that all military supplies would be identified and tracked using RFID, which greatly promoted the research and application of RFID technology and enriched and improved the theory of RFID technology.
Since the beginning of the 21st century, with the continuous reduction of the cost of RFID tags and reading equipment, RFID technology has been more widely used, and some people even call it the terminator of bar codes. RFID technology is also used in medical care, electronic ticketing, access control management, etc. Several large retailers and some government agencies have mandated that their suppliers must have RFID tags on boxes and pallets of products shipped from distribution centers.
In August 2009, former Premier Wen Jiabao proposed the concept of Perceiving China when he visited the Wuxi Internet of Things Industry Research Institute to inspect the construction of the Internet of Things. RFID technology will definitely form the front-end data collection platform of the Internet of Things together with the sensor network, and is the main component of the Internet of Things technology. Many people in the industry define 2010 as the first year of the Internet of Things.
With the increasing informatization of society and the continuous advancement of science and technology, people have higher and higher requirements for work efficiency and automation. RFID technology combined with Internet, communication and computer technology can realize the tracking and information sharing of items on a global scale. Applying it to industries such as logistics, manufacturing and public information services can greatly improve management and operational efficiency and reduce costs. With the continuous improvement, development and maturity of related technologies, the RFID industry will become an emerging high-tech industry group and a new highlight of national economic growth.
Current RFID research mainly focuses on technical standards, tag costs, key technologies and system applications.
(1)Technical standards. In order to standardize the development, design and mass production of tags and readers and solve the interconnection and compatibility issues of RFID systems, RFID technology must be standardized. The standardization of RFID is an important issue that needs to be solved urgently. Countries and relevant international organizations are actively promoting the formulation of RFID technical standards. At present, there are no complete international and domestic standards for RFID. The standardization of RFID includes identification encoding specifications, operating protocols, and application system interface specifications. The identification encoding specifications include identification length, encoding method, etc.; the operation protocol includes air interface, command set, operation process and other specifications. The current main RFID technical standards include the European and American EPC standard, the Japanese UID (Ubiquitous ID) standard and the ISO 18000 series of standards.
(2) Label cost. Tag cost is the key to limiting the success of commercial applications of RFID technology. RFID tags are mainly composed of IC chips, antennas and packages. According to the survey, the average price of passive HF band tags in 2003 was 91 cents, and the average price of UHF band tags was 57 cents. Some people predict that in the case of mass production, the production cost of RFID tags can be reduced to as low as 5 cents. By then, RFID technology will enter all areas of people's lives and provide people with cheaper, more efficient and more convenient services.
(3) Key technologies. Research on key RFID technologies mainly focuses on frequency selection, antenna technology, low-power technology, packaging technology, positioning and tracking, anti-collision and safety technology, etc.
Frequency selection: A key issue in RFID technology is the selection of operating frequency. The selection of operating frequency needs to be suitable for different applications and take into account the relevant regulations on the use of radio frequency bands and transmission power in various countries. The current working frequency of RFID spans multiple frequency bands, and different frequency bands have their own advantages and disadvantages. It affects not only the performance and size of the tag, but also the price of the tag and reader. In addition, differences in radio transmission power will also affect the range of the reader. To expand wireless coverage, the size of the tag antenna must be expanded. Low-frequency bands have relatively low energy, low data transmission rates, and limited signal coverage. However, the production cost of low-frequency tags is relatively low and comes in various shapes, making it easy to attach to the objects being identified and tracked. The high-frequency band has relatively high energy and is suitable for long-distance applications. At the same time, the data transmission rate in the high-frequency band is relatively high and the communication quality is good. Its disadvantage is that it is easily blocked by obstacles, easily affected by factors such as reflection and human body disturbance, and it is difficult to achieve full area coverage of the signal. Since the power loss of low frequency is proportional to the cube of the propagation distance, and the power loss of high frequency is proportional to the square of the propagation distance, high frequency can also be used for tag tracking and positioning.
Antenna technology: Due to limitations in application scenarios, RFID tags usually need to be attached to the surfaces of different types and shapes of objects, or even need to be embedded inside the object. At the same time, the tag and reader antennas also play the role of receiving and transmitting energy respectively. Efficiently sending and receiving data places stringent requirements on antenna design. The antenna structure determines the antenna pattern, polarization direction, impedance characteristics, standing wave ratio, antenna gain and operating frequency band and other characteristics. Current research on RFID antennas mainly focuses on the effects of antenna structure and environmental factors on antenna performance, such as research on patch antennas, inverted F-shaped antennas, and Sierpinski fractal structure antennas.
Low power consumption technology: Whether it is an RFID module working in an active or passive mode, in order to extend the life of the card, expand the application scenarios and improve the identification distance of the tag, one of the most basic requirements is low power consumption. In practical applications, reducing power consumption is as important as ensuring a certain effective communication distance. Therefore, the chips in the tags generally adopt very demanding low-power processes and high-efficiency energy-saving technologies. For example, [sleep mode] design technology is used in circuit design, and SMIC 0.18 um standard CMOS process design is used in hardware to realize memory and current-limited ring oscillator with full CMOS structure.
Packaging technology: Since antennas, chips and other special components need to be installed in RFID tags, special packaging technology and specialized equipment are required to ensure the size, thickness, flexibility of the tag and the safety of the chip circuit in the high-temperature and high-pressure process. The packaging of labels is not only limited by standard shapes and sizes, but its composition also varies widely, and even requires special design according to various requirements.
Positioning and tracking technology: The development of RFID technology provides a new solution for spatial positioning and tracking services, which is mainly used in indoor positioning areas where GPS is difficult to apply. The RFID positioning and tracking system mainly uses the tag's unique identification characteristics of the object to measure the spatial position of the object based on the strength of the radio frequency signal between the reader and the tag. Typical RFID positioning and tracking systems include the Cricket system developed by the MITOxygen project, the LANDMARC system of Michigan State University, and the RADAR system of Microsoft Corporation. This technology has been widely used to locate and track people in mines.
Anti-collision technology: With the emergence of active tags and the application of RFID technology in high-speed moving objects, there is an urgent need for readers to efficiently and quickly identify a large number of tags within a limited time. This will cause channel contention problems, which require anti-collision algorithms to solve. Anti-collision algorithms are divided into two types: reader-writer and tag anti-collision algorithms. The tag anti-collision algorithm is to solve the problem of multiple tags communicating with the reader at the same time within the effective communication range of the reader. In the high frequency (HF) band, tag anti-collision algorithms generally use ALOHA and related algorithms. In the ultra-high frequency (UHF) band, binary search algorithms are mainly used to avoid collisions. Commonly used anti-collision algorithms take a long time to identify and cannot meet the identification requirements for high-speed moving tags. Although most new algorithms have shorter recognition times, they have higher requirements on tag design. For example, they need to add random number generators, registers or delays, etc., which are difficult to meet the low-cost requirements of system design. Therefore, while maintaining a certain complexity and cost, minimizing search time and improving recognition efficiency are the directions and trends of anti-collision algorithm research.
Security technology: With the development of RFID technology and its application in military, security and financial fields, RFID-related security technology has become more important to protect information security and user privacy. With the continuous development of cryptanalysis and the emergence of various [hackers], RFID systems based on traditional security technologies are under increasingly serious threats. Due to the particularity of RFID devices, such as limited computing power, limited storage space and power supply, special requirements are put forward for the security design of RFID systems. Therefore, designing secure, efficient, and low-cost RFID security protocols remains a challenging research topic worldwide.
(4) System application. The technical advantages of RFID have broad application prospects. Current typical applications include: access control, animal husbandry, air parcel identification, logistics management, logistics management, mobile commerce, product anti-counterfeiting, sports timing, ticket management, parking lot control, production line automation, document tracking management, vehicle anti-theft material management, etc. In summary, it can include the following areas.
Commercial supply chain applications: The application of RFID technology in commercial supply chains will be the most extensive and in-depth application among all its application fields. It is also the most technically difficult and difficult application to implement. Because it is necessary to affix a label to all goods, this not only requires high label costs, but also requires back-end management systems and software that can process large amounts of data quickly and efficiently.
Public transportation management application: Public transportation management is the earliest and most successful field where RFID technology is applied. The main applications involved include: electronic tickets, non-stop toll collection and vehicle management and tracking.
Identification: Tags can be embedded in various valid documents such as ID cards, passports, and work permits to verify and identify personnel. They can also be placed in tubes and implanted in animal skins to track, research, and protect animals.
Anti-counterfeiting application: RFID technology is applied in the field of anti-counterfeiting and has the advantages of fast identification, difficulty in counterfeiting, and low cost. If security authentication and encryption functions are added, it can greatly increase the difficulty and cost of counterfeiting, making it more difficult for counterfeiters to retreat. To prevent counterfeiting and facilitate banknote transaction processing, Japan and Europe are experimenting with embedding tags in yen and euros.
Logistics management: In order to reduce logistics costs, improve transportation efficiency, and ensure that items will not be omitted or lost during transportation and circulation, the entire logistics process needs to be monitored and managed. The current application of RFID technology in the logistics field is mainly focused on the following aspects: railway and highway freight dispatching, container identification and tracking, automatic identification and processing of items and packages, etc.