RFID Basic Knowledge And Important Application

- Oct 07, 2018-

RFID (Radio Frequency Identification) is commonly known as "electronic tag". It is a non-contact automatic identification technology. It automatically recognizes the target object and acquires relevant data through radio frequency signals. The identification work does not require manual intervention as a wireless version of the barcode. RFID technology has the advantages of waterproof, anti-magnetic, high temperature resistance, long service life, large reading distance, data encryption on the label, larger storage data capacity, and free storage information. The application will be for retail, Logistics and other industries have brought revolutionary changes.

The radio frequency tag is physically composed of three parts: a tag, an antenna, and a reader/writer.

Tag: consists of a coupling element and a chip. Each tag has a unique electronic code. The high-capacity electronic tag has a user write area attached to the object to identify the target object.

Reader: A device that reads (and sometimes writes) tag information and can be designed to be handheld or fixed;

Antenna: Transmits RF signals between the tag and the reader.

RFID features

Data storage: Compared with traditional forms of tags, the capacity is larger (1 bit - 1024 bit), the data can be updated at any time, and can be read and written;

Read and write speed: Compared with barcode, it does not need linear alignment scanning, and the reading and writing speed is faster, and multi-target recognition and motion recognition can be performed;

Easy to use: small size, easy to package, can be embedded in the product;

Security: dedicated chip, serial number unique, difficult to copy;

Durable: no mechanical failure, long life and resistance to harsh environments.

How RFID works

The basic working principle of RFID technology is not complicated: the reader sends a specific frequency of the radio frequency signal through the transmitting antenna, and when the electronic tag enters the effective working area, an induced current is generated, thereby obtaining energy, and the electronic tag is activated, so that the electronic tag encodes itself. The information is sent out through the built-in RF antenna; the receiving antenna of the reader receives the modulated signal sent from the tag, and transmits it to the reader signal processing module via the antenna adjuster. After demodulation and decoding, the valid information is sent to the background host system. Correlated processing; the host system identifies the identity of the tag according to the logical operation, and performs corresponding processing and control for different settings, and finally issues a command signal to control the reader to complete the corresponding read and write operations.

RFID classification

According to the presence or absence of power, it is divided into Passive and Active:

Passive Tag:

The Passive sensor itself has no power supply. The power supply is from the Reader. The Reader emits a frequency to make the sensor generate energy and return the data to the Reader. The volume is relatively light and thin, and has a long service life. The sensing distance is short.

Active Tag (active): The price is higher. Due to the built-in battery, the volume is larger than the Passive tag, and it has a long service life and a long sensing distance.

According to the frequency, it can be roughly divided into three categories: LF, HF and UF:

Low Frequency: 100~500KHz The low-frequency sensing distance is short and the reading speed is slow. It is mainly 125KHz and has good penetration ability.

High Frequency: 10~15MHz The sensing distance of the high frequency is slightly longer, and the reading speed is also lower than the frequency, which is mainly 13.56MHz;

Ultra High Frequency/Microwave: Between 850 and 950 MHz (UHF) and 2.45 GHz, the sensing distance is the longest, the speed is the fastest, and the penetration is poor.

RFID application

As a data carrier, electronic tags can play the role of identification, item tracking and information collection. In foreign countries, electronic tags have been applied in a wide range of fields. The RFID system consisting of electronic tags, readers, antennas and application software is directly connected to the corresponding management information system. Every item can be accurately tracked. This comprehensive information management system can bring many benefits to customers, including real-time data collection, secure data access channels, and access to all product information offline. Wait. In foreign countries, RFID technology has been widely used in many fields such as industrial automation and commercial automation.

Applications include:

Product anti-counterfeiting

Valuables management

Access control / identification

Material/product tracking

Personnel item location

Transportation and distribution

Air baggage tracking

Electronic traceability, food traceability

Production line management

Railway transportation management system

Warehouse management, intelligent warehouse management

Electronic Article Surveillance (EAS), clothing retail store export management

Anti-theft management, unauthorized use management or asset management of valuable equipment

Vehicle, parking lot and gas station, warehouse facility management

Automatic collection of passing bridge fees

Access control management for important and dangerous occasions

Conference and Timing - Typical Applications

Animal management, personalized feeding

Automatic identification of CNC machine tools

Product quantity and process control in flexible processing systems

Surveillance of suspects

Vehicle anti-theft system and car ignition system

Intelligent library, lease product management

Application management of car anti-theft and keyless door opening system