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How does a passive RFID tag work?
Passive RFID uses high-power readers that send out a low-frequency, high-power RF signal to battery-free tags. The antenna in the tag is woken up by the amount of energy flowing to it, which wakes up its circuit. The tag then transmits a coded message back to the reader at a different frequency.
What is passive RFID?
In passive RFID systems the reader and reader antenna send a radio signal to the tag. The RFID tag then uses the transmitted signal to power on, and reflect energy back to the reader. Passive RFID systems can operate in the low frequency (LF), high frequency (HF) or ultra-high frequency (UHF) radio bands.
The tag antenna is deposited or printed on the substrate, and the IC is then attached to this antenna. A substrate is usually made from flexible material such as thin plastic, but it may also be made from rigid material. Most passive tags use substrates made from flexible material with a thickness of 100 to 200 nm.
What is the advantage of RFID passive tags?
The advantages of a passive tag are: The tag functions without a battery; these tags have a useful life of twenty years or more. The tag is typically much less expensive to manufacture. The tag is much smaller (some tags are the size of a grain of rice).
How does a passive RFID tag work and antenna design?
Passive RFID tags have no battery source and rely on the electromagnetic coupling of an antenna for their power. This leaves them with a shorter reading distance of up to 20 feet.
RFID tag classes range from Class 0 through Class 5 and define available functionality. Class details include: Passive or active read-write tags with added sensors for recording temperature, pressure, and motion. Active read-write tags with integrated transmitters that can communicate with other tags and readers.
What are the advantages and disadvantages of RFID?
RFID wireless technology has provided enormous benefits to logistics, inventory control, and retail industries, but that doesn’t make it a perfect technology. However, when compared with barcodes and other manual scanning systems, RFID has some noticeable advantages, including: Scanning multiple items simultaneously.
Is it worth learning about RFID and antenna design?
This presents some new opportunities for electronics designers wanting to learn about RF and antenna design. While RFID accomplishes the same functionality of a barcode or magnetic strip on a credit card, it has some unique use cases that make it worth learning about and designing.