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serial - Arduino with Parallax RFID reader storing ...

I am quite new to electronics and have been tinkering around with this Arduino UNO w/ WiFi Shield and the Parallax RFID R/W Module.

Link to the RFID Module: http://www.parallax.com/Store/Accessories/CommunicationRF/tabid/161/ProductID/688/List/0/Default.aspx?SortField=ProductName,ProductName

Link to it's Data Sheet:...

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Related topics : parallax rfid read write module / rfid read write module arduino / parallax rfid card reader serial arduino / rfid read write module / rfid card reader serial parallax

arduino - Electronic pet-door access control - RFID ...

Inspired by projects such as the tweeting cat door and CATaLOG [sic] I'm wanting to add some form of automated access control to our pet door to control who can go in and out, when.

(Full Disclosure: This is a reprint from my blog where I first wrote up the problem, but all feedback is welcome!)

The Players

We currently have three cats, one dog and one pet door.

The Mischievous Mutt

Toby, our two...

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Related topics : door access control rfid / rfid tag detection range / active rfid tag range / rfid tag range / rfid pet door arduino

arduino - Electronic pet-door access control - RFID ...

Inspired by projects such as the tweeting cat door and CATaLOG [sic] I'm wanting to add some form of automated access control to our pet door to control who can go in and out, when.

(Full Disclosure: This is a reprint from my blog where I first wrote up the problem, but all feedback is welcome!)

The Players

We currently have three cats, one dog and one pet door.

The Mischievous Mutt

Toby, our two...

Read more

Related topics : door access control rfid / rfid tag detection range / active rfid tag range / rfid tag range / rfid pet door arduino

UHF RFID Read Ranges - Stack Exchange

up vote 2 down vote

I'm going to examine the maths of transmitting power from a point source (the reader antenna) and assume the passive tag has an antenna that can pick-up, rectify and re-use a fraction of this power. This doesn't consider near-field effects/benefits (these may save the day but my gut feeling suggests they won't).

The reader antenna is pumping out +20dBm - that's a power of...

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Related topics : passive rfid tag antenna / uhf rfid tag antenna / rfid tag antenna / uhf near field rfid reader antenna / uhf passive rfid tag reader

What can I do to increase passive HF RFID read range?

up vote 6 down vote accepted

I can only relate my experiences: -

If you want to detect a normally-not-powered passive type tag at extreme distances you have to power to that tag from a significantly bigger magnetic field. Making your magnetic field stronger is the only way I can know (and can recommend). Making your tag more efficient in recovering a fraction of this power is also part of the...

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Related topics : passive rfid tag read range / passive rfid tag distance / passive rfid tag frequency range / passive rfid read range / types of passive rfid tags

What can I do to increase passive HF RFID read range?

up vote 5 down vote accepted

I can only relate my experiences: -

If you want to detect a normally-not-powered passive type tag at extreme distances you have to power to that tag from a significantly bigger magnetic field. Making your magnetic field stronger is the only way I can know (and can recommend). Making your tag more efficient in recovering a fraction of this power is also part of the...

Read more

Related topics : passive rfid tag read range / passive rfid tag distance / passive rfid tag frequency range / passive rfid read range / types of passive rfid tags

rfid - Can I use a NFC ring as an Oyster card ...

Newer applications use ISO/IEC 14443-4 standardized application cards (like payment cards from V/M/Amex, and NXP offers a proprietary extension of these called DESFire for transit agency issued cards).

The Oyster MIFARE cards are programmed at the factory (or by the system operator from blank devices) and are activated upon enrollment to the system. The readers at the turnstiles and behind the...

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Related topics : rfid key card system / mifare contactless card reader / rfid key card / mifare rfid card reader / mifare rfid cards

Power requirements for NFC (RFID) chip - Stack Exchange

You need to distinguish worst case and average power consumption. It occurs to me you are more interested in the latter.

Average power consumption

Here you have to understand how RFID and specifically 14443 A work. In a nutshell, the reader keeps its antenna resonating at 13.56 MHz, and when a token is in the field, the latter gets power. Token has an antenna tuned to the same frequency...

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Related topics : rfid reader antenna / rfid chip card reader / nfc rfid card reader / rfid tag and reader working

Can the range of a monostatic RFID antenna be increased ...

up vote 1 down vote

These are two questions.

(1) How does an RFID reader monostatic antenna both transmit and receive at the same time, are they CW or pulsed?

Through a magical device called a circulator. This is a (typically) three-port device. The energy flowing into port 1 is directed out port 2. The energy flowing into port 2 is directed out port 3, and likewise, the energy in port 3 is...

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Related topics : rfid reader antenna / rfid reader read range / rfid reader range extender / rfid reader range