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Walmart to Push RFID
bravehamster writes "According to this article over at MSNBC, Walmart is going to push its suppliers to start using RFID to track inventory by 2005. The article goes on to mention how it was Walmart who helped jumpstart widespread adoption of barcodes. The report also points out some of the barriers in the way of RFID acceptance, but never once mentions consumer privacy concerns. Guess that kind of stuff just isn't important anymore."
It is very unlikly these devices will come with a power supply that lasts much longer than the expected shelf life of the item being sold.
RFID tags need no power supply. They are powered by the reader. (From the radio waves emitted by it.)
From this page:
An RFID system consists of an antenna or coil, a transceiver and a transponder or tag. A radio signal emitted by the antenna activates the tag allowing it to be read and in some instances have data written to it.
Passive RFID tags require a powered reader unit (such as a handheld unit similar to the ones used for barcodes or a stationary unit) which query the RFID for the information. Since these RFID tags have no power source of their own, even with a powered reader unit the maximum reading distance is ***A FEW FEET***. The amount of data that is able to currently be stored on passive RFID tags is quite small as well. Passive RFID tags are fairly cheap, however unless breakthroughs have been made in the last 6-8 months, they still are not cost effective to stick on anything and everything.
Powered RFID tags are battery powered and are capable of storing substantially more information than passive RFID tags. Signal distance is also further than passive RFID tags however still, unless you had a reader unit in your house or some sort of truck mounted reader unit went through the neighborhood any RFID tags in your house would be unreadable, the distance even powered RFID tags is pretty short. Tags such as these cost a few dollars each, definately not cost effective to stick on just anything.
As stated in the article, and from my experience visiting a Walmart regional distribution center, is that RFID tags will be used for logistics/distribution operations. Even if they were going to start sticking RFID tags on everything tomorrow(which would be prohibitedly expensive) their distance limitations would make them useless once you got out into the parking lot, and that erring on the generous side on the distances they can transmit. So unless you have a RFID reader in your house, no worries.
For the above questions, 1) For a consumer to detect a tag is pretty obvious, they are not that small, plus, all RFID technologies I am aware of require an antennae which would be a give away even if the tag was somehow incorporated inside the product with a small antannae sticking out. Researchers at Motorola have been investigating doing away with the need for an antennae however, maybe they have overcome this issue. 2) No ideas