RFID Protocol Standard

When it comes to RFID, there are several protocol standards that cannot be avoided. No matter which field, the application of RFID systems must comprehensively consider the location, distance, temperature, humidity, interference and many other factors that affect system performance. Two different countries also have different standards for RFID standards. strict requirements. So let's talk briefly about the RFID protocol standard today.

The RFID tag realizes the communication with the RFID reading and writing equipment through the built-in chip, among which the RFID tag protocol plays an important role. The RFID tag protocol is jointly formulated by ISO and the International Electrotechnical Commission (IEC). Our common and commonly used RFID standards are as follows.

LF RFID Standard

Low frequency RFID standards: ISO11784, ISO11785

The working frequency range of the low frequency band is 30kHz～300kHz. Typical operating frequencies are: 125KHz, 133KHz, 134.2khz. The communication distance of low frequency tags is generally less than 1 meter.

ISO 11784 and ISO11785 respectively specify the code structure and technical guidelines for animal identification. The standard does not specify the size of the transponder style, so it can be designed in various forms suitable for the animals involved, such as glass tubes, ear tags or collars Wait.

The technical standard stipulates the data transmission method and reader specification of low-frequency RFID. The working frequency is 134.2KHz, the data transmission mode has two kinds of full-duplex and half-duplex, and the reader data is represented by differential bi-phase code. The communication rate is low due to the long transponder charging time and operating frequency limitation.

High-frequency RFID standard, also known as NFC standard

High frequency RFID standard: ISO14443A&B and ISO15693

The working frequency of high-frequency electronic tags is generally 3MHz ~ 30MHz. The typical operating frequency is: 13.56MHz. The basic characteristics of the high-frequency standard are similar to those of the low-frequency standard. Due to the increase of its operating frequency, a higher data transmission rate can be selected.

ISO14443 defines two types of protocols, TYPE A and TYPE B. They differ mainly in the modulation depth of the carrier and the way the bits are encoded. ISO 14443A is generally used for Access Control cards, bus cards and small Stored-value consumption cards, etc., and has a relatively high market share. ISO14443B is more suitable for CPU cards because of its relatively high encryption coefficient. It is generally used for ID Cards, pasSports, UnionPay cards, etc. The current second-generation electronic ID card adopts the ISO 14443B protocol.

The carrier frequency specified in ISO15693 is 13.56MHz. This standard defines the air interface and data communication specifications of smart tags and readers working at 13.56Mhz. The farthest reading distance of tags that meet this standard can reach 2 meters, and the application is more flexible.

UHF RFID Standard

UHF RFID standard: ISO18000-6 B and ISO18000-6C (EPC C1 G2)

The UHF electronic tag has a large reading distance, and its typical operating frequency is 433.92MHZ, 902~928MHz. UHF tags are mainly used for automatic identification of railway vehicles and container identification, and can also be used in road vehicle identification and automatic toll collection systems.

The application of ISO18000-6B standard is relatively mature, the product performance is relatively stable, and the data format and standard are relatively simple. In terms of reading speed and the number of labels, in applications where the number of labels is not large, such as bayonet ports and dock operations, the application of ISO18000-6B standard labels can basically meet the needs. At present, the "electronic license plate recognition system" used in China's customs logistics supervision system uses the electronic label of the ISO18000-6B standard.

ISO18000-6C (EPC C1 G2) is fast, the data rate can reach 40kbps ~ 640kbps, a large number of tags can be read at the same time, it has multiple write protection methods, and has strong security. But the current user data area is small and the capacity is not enough.

Protocol standards are the basis for communication between RFID devices. Therefore, it is very important to unify protocol standards and frequencies. At the same time, different protocol standards determine different application scenarios.