EAS+RFID Tag Configuration

[engsamir]

Hi All ,
I just want to confirm if i got this right .

RFID + EAS (electronic article surveillance) use to 2 different frequencies for configuration (one for for RFID part 800-900MHz and the other one to set up arm/disarm the EAS which is 8.2Mhz ) , is this correct?
if yes then can any one please provide me with a reference on how to design 8.2Mhz compact antenna ( 30*30 cm max or smaller if possible ,for near detection ), i assume it will be a loop antenna :roll: ???
if i got it all wrong i hope someone can explain it to me ...


Tq

 

[FvM]

Diffferent RFID standards use different frequencies, e.g. 125 kHz, 13.56 MHz and 900 MHz.

RF EAS tags are simple passive LC resonators, see Wikipedia article: https://en.wikipedia.org/wiki/Electronic_article_surveillance

These tags are essentially an LC tank circuit that has a resonance peak anywhere from 1.75 MHz to 9.5 MHz. The most popular frequency is 8.2 MHz. Sensing is achieved by sweeping around the resonant frequency and detecting the dip. Deactivation for 8.2 MHz label tags is achieved by detuning the circuit by partially destroying the capacitor. This is done by submitting the tag to a strong electromagnetic field at the resonant frequency which will induce voltages exceeding the capacitor's breakdown voltage, which is artificially reduced by puncturing the tags.

 

[engsamir]

Diffferent RFID standards use different frequencies, e.g. 125 kHz, 13.56 MHz and 900 MHz.

RF EAS tags are simple passive LC resonators, see Wikipedia article: https://en.wikipedia.org/wiki/Electronic_article_surveillance

thank you for your explanation, I hope if you or anyone else can give me a reference on how to design a small 8.2Mhz patch antenna

 

[FvM]

how to design a small 8.2Mhz patch antenna

A patch antenna for 8.2 MHz would have a size > 10 m. EAS and 13.56 MHz RFID systems are using resonant loop "antennas". You can refer to design guides for long range RFID and change it to 8.2 MHz, e.g.:
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