MadModder
The Shop => Electronics & IC Programing => Topic started by: shipto on January 23, 2015, 08:48:48 PM
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Could anyone point me in the direction of a rfid module thats capable of reading tags from about 500mm for a dog flap project I am working on trawling google has become increasingly tedious.
The module would be hooked up to arduino.
Thanks in advance
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Had a quick look on eBay and there are a few on there. Not sure on the range though.
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Most of the commonly-available low-power short-range RFID kit works on either LF (Low Frequencies - of the order of 120-150 kHz) or HF (High Frequencies- in this case around 13.5MHz). Although terrestrial radio propagation is generally further at those lower frequencies, the permitted radiated power is so low that the effective range can be of the order of just tens of millimetres at LF (as used to 'chip' your pet) or a little more in HF kit.
Longer range RFID kit typically operates at UHF (Ultra High Frequency) - typically in bands around 430MHz, 860MHz and 910MHz depending on your local legislation. Unfortunately the much smaller market for UHF RFID typically adds an extra 0 or 00 to the end of the price tag.
Try googling for RFID UHF and that may help narrow your search.
Dave
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Thanks both I carried on searching using various keywords after I posted this and found much the same as you say the extra expense is quite a lot.
some of the commercial doors use the existing chip the pet is implanted with which I believe are only 125khz so it should be possible some way but i will keep searching until i stumble upon the answer.