RFID - Radio Frequency Identification Technology

The main task of the automated information system is to ensure that the information obtained is as reliable as possible. This is absolutely necessary, because it will take a lot of time and money to search and screen out incorrect information in large data arrays. To these losses it is also necessary to add direct losses, to which an inadequate decision can be taken, made on the basis of incorrect information.

Automatic identification technologies, including the recognition and registration of objects in real time without human intervention, most fully correspond to this task. These technologies are based on bar coding or radio frequency coding.
Radio Frequency Identification (RFID), or RFID (Radio Frequency Identification), as it is called abroad, is the most advanced identification technology, providing significantly more opportunities than others. It is based on the technology of transmitting information using radio waves, which is necessary for recognizing (identifying) objects with special tags attached to them that carry both identification and user information.


The main advantages of RFID technology
The direct visibility of the radio frequency tag is not required to read information from it, therefore the tag can be located inside the package (if it is not metallic), ensuring its secrecy and preservation
High speed tag reading, which can reach 1000 pcs per second.
It is possible to almost simultaneously read a large number of tags using the anti-collision function.
It is possible to change the information in the label if it belongs to the class "read-write" (Read / Write)
The ability to read and write tags at a distance
Durability. For read-only operations, the label's lifetime is almost unlimited.
High degree of security, which is ensured by the use of a unique identifier of the label assigned at the factory during its manufacture, as well as encryption of the data recorded in the label
Resistance to the environment, since the label can always be placed in any protective polymer shell

What is the RFID system
Tags (tag) or transponders - devices that can store and transmit data. The tag memory contains their unique identification code. Some types of labels have rewritable memory.
Readers - devices that receive information from tags using antennas and also write data to them
Antennas are used to induce an electromagnetic field and obtain information from tags that fall into this field.
A reader management system (middleware) - software that generates requests for reading or writing tags, controls readers, combining them into groups, accumulates and analyzes information received from tags, and also transmits this information to accounting systems
How does the RFID system work
Before the system starts, the label must be applied or attached to the object (object), the movement of which must be taken into account.
The object with the label must pass the initial registration in the system using a stationary or portable reader.
Readers with antennas should be placed at the control points of the object movement accounting. This completes the preparatory phase.
The control over the movement of the object will consist in reading the tag data in the control points, for which the mark needs to fall into the electromagnetic field created by the antenna connected to the reader. Information from the reader is transmitted to the control system and then to the accounting system, on the basis of which the accounting document is generated. In the case of group reading of tags, the data of all read tags fall into one accounting document, which records the movement of objects.

How RFID tags are arranged
The label is a miniature memory device. It consists of a microchip that stores information, and an antenna, with which the tag transmits and receives information. Sometimes the tag has its own power source (such tags are called active), but most tags do not have it (these tags are called passive) and receive energy for work from the electromagnetic field induced by the antenna and accumulates it in a capacitor.
The tag's memory stores its own unique number and user information. When a tag enters the registration area, this information is received by the reader, a special device capable of reading and writing information in the tags.
What are RFID tags
RFID technology can be implemented in many areas. In order for systems based on this technology to work effectively in any environment, many labels of the most diverse designs have been developed. They can be divided into the following signs
1. On energy supply
Active - use for the transfer of data the energy of the built-in battery
Passive - use the energy emitted by the reader through the antenna
Semi-passive - such labels also have a battery, but it is used only to ensure the operation of the chip, and not to communicate with the reader, which significantly extends the life of the battery.
2. By read-write operations
"R / O" (Read Only - "read only") - the data is written only once during the manufacture of the label. Such tags are only suitable for identification. No new information can be recorded in them, and it is almost impossible to fake them.
“WORM” (Write Once Read Many - “write once and read multiple times”) - in addition to the unique identifier, such tags contain a block of once written my memory, which can be repeatedly read
"R / W" (Read and Write - "read and write") - such tags contain an identifier and a block of memory for reading / writing information. The data in them can be overwritten a large number of times.
 3. By tag performance
No adhesive layer (inlay or insert)
With adhesive layer without surface for printing
With adhesive layer and surface for printing
Standard plastic cards
Tags in the form of a ring
Different types of keyrings
In a special case for special operating conditions.
Frequencies and standards
Today, RFID systems use four frequency bands: 125-150 kHz, 13.56 MHz, 862-950 MHz, and 2.4-5 GHz. What explains the choice of these frequency bands? These are the frequencies for which most countries are allowed to conduct commercial development. For example, we note that the range of 2.45 GHz is the frequency at which wireless devices of the standard Bluetooth and Wi-Fi work.
Each of the mentioned frequency ranges has its own standards with its degree of development. Their most common characteristics are presented in the table.
Range name
Operating frequency
Standard
Applications
Low Frequency (LF)
125-150 kHz
ISO 14223
ISO 11784/11785
ISO 18000-2
They are used in access control systems, to identify animals, and are also widely used, for example, in car immobilizers
Treble (HF)
13.56 MHz
ISO 14443
ISO 15693
ISO 10373
ISO 18000-3
Used in access control systems, payment systems, as well as to identify goods in storage systems and books in library systems
Ultra High Frequency (UHF)
860-960 MHz
2.4-5 GHz
U-code
18000-4
18000-6
A scope are systems of logistics and accounting of traffic. A distinctive feature is the increased range and high reading speed.

What are the readers
Instruments for reading and writing data in tags (readers) can be divided into
Hand-worn on hand
Mobile - mounted on vehicles
Stationary - mounted on fixed objects
Hand readers. As a rule, such readers are combined with data collection terminals. They have a shorter range (read and write) because they are limited by the power source. If there is a wireless connection in the data collection terminal, there can be a constant data exchange with the accounting system. Manual readers are also able to write data to the tag (for example, information about the operation performed).
  Mobile readers. Since such readers have a more powerful power source, they have a greater range and speed of reading than manual ones. However, they can also be equipped with a wireless connection, providing real-time operation.
Stationary readers. This type of reader provides the highest possible performance in range and speed. They connect to the system via Ethernet. These readers can work with antennas of various types.
What are the antennas
Antenna is an essential element of the RFID system.
All manufactured antennas can be classified (depending on frequency):
By range (short, medium and long range)
By execution (desktop, stationary and portal)
By the direction of polarization (left-sided, right-sided, two-sided)
By speed of operation (normal, fast)
Only properly selected and tuned antennas can ensure uninterrupted operation of the reader with tags, achieving the highest possible results.

Where is this technology applied
The scope of application of RFID technology is constantly expanding. The main areas of application of radio frequency identification technology today are:
Storage facilities
Logistics and supply chain management from producer to consumer in real time
Identification of moving objects in real time (accounting of vehicles, cars in moving trains)
Identification of vehicles in parking lots, bus stations
Identification automation on assembly lines in industrial production
Access control systems in premises and structures
Providing passengers with electronic tickets
Express parcel delivery
Baggage handling and delivery on airlines
Car Security Systems
Verification of payment system transactions for accuracy
Prevent counterfeiting of various product categories
Marking (identification) of property, documents, library materials
Automated car gas stations
And etc.

In stock, real-time RFID automatically tracks the movement of goods, significantly accelerates the basic processes of acceptance and shipment, increases productivity, reliability and transparency of operations while reducing the influence of human factors.

On production, RFID records the movement of semi-finished and finished products in real time, monitors technological operations and the quality of the product. Products receive a kind of "electronic passport" that allows you to work on its quality at a new level.

In the consumer goods and retail industry, RFID systems track goods at all stages of the supply chain, from the manufacturer to the counter. The goods are put on the shelf in time, do not lie on the warehouse and are sent to those stores where there is a higher demand for it.

In libraries, the entire movement of the book stock is automatically controlled by this technology. To do this, each unit of the book fund must be marked and readers must receive electronic library cards. A reader, having registered at the entrance, chooses the books he needs and records them to his electronic reader card. Books not written to the readers' subscription can not be taken out of the hall, because output readers are watching for this.

In addition to the existing RFID applications, which will be further developed, there are many areas that are ready to adopt technology. Daily there are messages about new ways of applying the technology.
The potential of using RFID is enormous.