RFID Reader Distance

timextimex Posts: 21
edited February 2011 in Accessories Vote Up0Vote Down
Most of the RFID Readers available can only communicated with RFID tags within 2 - 5 inches.
Is there anyway to increase this distance?



  • 6 Comments sorted by Date Added Votes
  • Bobb FwedBobb Fwed Posts: 1,105
    edited September 2010 Vote Up0Vote Down
    I think the problem with the distance isn't so much that the device cannot communicate, but rather it cannot transmit enough power wirelessly to the RFID key to have it transmit at further distances.

    Personally I think 5 inches is a pretty good distance to power a device wirelessly and still have it send information back, wirelessly.
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  • Invent-O-DocInvent-O-Doc Posts: 767
    edited September 2010 Vote Up0Vote Down
    I know industry can do it more distantly, but I think they used self-powered tags.

    Thomas Talbot, MD - New Market, Maryland, USA
  • Daniel HarrisDaniel Harris Posts: 207
    edited September 2010 Vote Up0Vote Down
    From what I understand about the "Toll-Tag" systems used for toll roads is that those are RFID. The tags in the car dont have batteries. A senior project team I worked with a few years back did a system that utilized that sort of RFID technology - with the huge power amplifier and antennas. They were able to get good readings 25 ft away, but that box was really expensive (> $2000) and required alot of power.
    Daniel Harris
    Application Engineer, Parallax Inc
    (916) 632-4664 x 3003
  • VonSzarvasVonSzarvas Posts: 527
    edited October 2010 Vote Up0Vote Down
    Wavetrend have Active RFID tags that work easily over 20meters and last 5 years on the built-in coin cell ! Also, an RS232 serial reader, which is small and easy to interface to your uC.

    Last time I checked the tags were about 20gbp and the reader 60gbp. Might be less... They don't sell small qty's direct, but lots of resellers worldwide to check for prices.


    Might be worth a look.. Might be other manufacturers too if you search on Active Rfid.
  • RagtopRagtop Posts: 406
    edited February 2011 Vote Up0Vote Down
    Has anyone tried applying power to a passive RFID tags to try and turn it into an active one?

    I just got an idea for a fox and hare game idea, trying to figure out the cheapest way to make each person's transponder.

    But I guess each player would need a tag and a reader, which would put me nearly in the price range of xbees.

    I am only looking at a range of 20 to 100 feet to count as a point for the foxes.
    Thomas Fletcher
    Ocala, FL
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