Saturday, January 22, 2011
【 Weak current College 】 RFID tag (RFID) classification profile 】
From the application of the concept, the RFID tag's operating frequency is the frequency identification system operating frequency, is one of the most important features.
RFID frequency is one of the most important features. RFID frequency not only determine the RFID system works (inductively-coupled or electromagnetic coupling), recognition distance, also determines the RFID tag and reader implementation of ease and equipment costs.
Work in different frequency bands or frequency of electronic tags have different characteristics. RFID application in occupies a band or frequency with an international recognized partition, that is located in the ISM band. Typical operating frequency: 125kHz, 133kHz, 13.56MHz, 27.12MHz, 433MHz, 902 ~ 928MHz, 5.8GHz 2.45GHz, etc.
1. low frequency RFID tag
Low frequency RFID tag, also known as low-frequency tags, their operating frequency range 30kHz ~ 300kHz. Typical operating frequency: 125KHz, 133KHz (also close to other frequencies, such as TI use 134.2KHz). Low-frequency tags generally passive tags, their energy through inductively coupled manner from reader coupling coil radiation near-field. Low-frequency tags and readers when transferring data between the low-frequency labels required is located in the reader antenna radiation near-field region. Low-frequency tags reading distance is generally less than 1 m.
Typical applications of low-frequency tags: animal identification, the container identification, tools, identification, electronic locking anti-theft (with built-in transponder car keys). And low-frequency tags related international standards: ISO11784/11785 (for animal recognition), ISO18000-2 (125-135kHz). Low-frequency tags have a variety of forms, apply to the appearance of animal identification of low-frequency tags look: tiara, ear tag type, injection-type, pills, etc. Typical applications of animals such as cattle, pigeons, etc.
The main advantage of low-frequency tags in: tag chip generally use normal CMOS process with power saving features, cheap; operating frequency is not supported by the radio frequency control; you can pass through water, organic tissue, lumber, etc.; ideal for close-range, low-speed, amount of data requiring less recognition application (for example: animal identification), etc.
The disadvantage of low-frequency tag primarily reflected in the amount of data: label store; you can only fit with fewer low-speed, close-recognition applications; and compared HF tags: tag antenna turns more and more expensive;
2. high frequency RFID tag
High frequency RFID frequency generally 3MHz ~ 30MHz. Typical operating frequency: 13.56MHz. The band's electronic labels, from the perspective of RFID application, because it works in exactly the same with the low-frequency tags, using inductively coupled manner,
It should be classified as a low-frequency tags class. On the other hand, according to the General Division of the radio frequency, its working band, also known as high-frequency, also often referred to as high-frequency tags.
High-frequency electronic label generally use passive mode, its work low frequency energy and, like the label is through the inductor (magnetic) coupling coil from reader coupled radiation near-field. Tag and reader for data exchange, the label must be located in the reader antenna radiating near field region. The if label reading distance typically have less than 1 m (maximum reading distance 1.5 m).
High-frequency tags because you can easily make the card shape, typical applications include: electronic tickets, electronic cards, electronic locking anti-theft (electronic remote control door lock controller). Relevant international standards are: ISO14443, ISO15693, ISO18000-3 (13.56MHz), etc.
The basic characteristics of high-frequency standard and low-frequency standard is similar, because of its operating frequency increases, you can choose the high data transfer rate. RFID antenna design is relatively simple, the label made of standard cards in General.
3. the labelling of UHF and microwave
UHF and microwave band RFID tag, also known as microwave electronic tags, their typical work frequency: 433.92MHz, 862 (902) ~ 928MHz, 2.45GHz, 5.8GHz. Microwave electronic label can be divided into active and passive tag labels. Work, the RFID tag is located in the reader antenna radiation field in the far field, tag and reader coupling for electromagnetic coupling. Reader antenna radiation pattern for passive tags provide RF energy, there will be a wake-up source label. The reading distance of RFID system generally greater than the typical situation for 1m 4 ~ 7m, up to 10m above. Reader antenna generally are directional antenna, antenna only if the reader is directed beam wide electronic tags can be read/write.
Because the reading distance increases, the application may read zone appears more electronic label, which has made a number of labels at the same time read the requirements of this kind needs to become a trend. At present, advanced radio frequency identification systems will be more labels to read issue as an important feature of the system.
In the present technological level, passive microwave electronic label relatively successful products relatively concentrated in 902 ~ 928MHz working band. 2.45GHz and 5.8GHz RFID systems to half a passive microwave electronic label products available. Half-passive tags generally use button battery with distant reading distance.
Microwave electronic tag primarily in typical characteristics is passive, wireless reading distance, whether or not to support multiple tags, reading, writing, is suitable for high speed recognition application, reader of transmitter power tolerance, RFID tag and reader price. For wireless write RFID tag, typically write distance than the reading distance, because writing requires more energy.R>
Microwave electronic label data storage capacity within the General limit, no matter how big the 2Kbits storage capacity seems to have little significance, from technology and application perspective, microwave electronic tags are not suitable for large amounts of data carrier, its main function is to identify the goods and completed the contactless identification process. Typical data capacity indicators are: 1Kbits, 128Bits, 64Bits, etc. The products developed by Auto-IDCenter e-code EPC of capacity of: 90Bits.
Microwave electronic label of typical applications include: mobile vehicle identification, electronic ID card, storage and logistics applications, electronic locking anti-theft (electronic remote control door lock controller). Relevant international standards are: ISO10374, ISO18000-4 (2.45GHz),-5 (5.8GHz),-6 (860-930MHz), a-7 (433.92MHz), ANSINCITS256-1999.