What is RFID? Imagine that you're the supervisor of a hospital. Before giving medication to a patient or even perform surgergy on him, you'd better make sure this is the right patient! With RFID, as long as a patient wears a special wrist band, when doctors and nurses meet him, they can magically find out who exactly this patient is. In fact, they could even locate the position of any patient in the hospital in a snap.
How does it work? The wrist band contains a chip called an RFID tag which stores an unique id for the patient. The tag can be as small as a grain of a rice or can be as large as a book. Doctors can use a hand-held device called an RFID reader to read the unique id in RFID tag. The best part is that, they don't need to put the reader in front of the tag. As long as they're within say a few meters, the reader can find it. It works even if RFID tag is hidden such as inside a pocket. To detect where a particular patient is, we can just install RFID readers in door frames.
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| Illustration 1 Three RFID tags of different shapes. There is a coin on the left so that you can see their sizes. | Illustration 2 RFID tag
that is embedded inside a regular adhesive label |
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| Illustration 3 RFID
reader installed at entrance/exit |
Illustration 4 RFID reader |
This is just one application of RFID. Airlines around the world are sticking RFID tags to baggages that store either a unique id for the baggages or some information of the passengers, so that the passenges know exactly where their baggages are. WalMart, the largest retailer in the world, is using RFID tags for tracking the products on its supply chain. Many car keys already contain an RFID tag and the cars will check if the RFID tag is indeed there before they can be ignited. Many organizations are using RFID tags in security bages for access control. In Hong Kong, a very popular application of RFID is the Octopus card. It is used as e-cash and can be used as an access control card. Each such Octopus card contains an RFID tag that stores the amount of cash remaining.
What is the cost of an RFID system? Tags may cost from MOP3 to MOP80 each or much more, depending on what features you'd like. For example, some tags can be written to just once in factory (like those used to track patients) but some can be written many times during use (like the Octopus cards); some tags can be read only within a inch from the reader but some can do in 10 meters or even more; some tags can store only a number of say 12 digits but some can store several pages of information or more. RFID readers may cost from MOP4,000 or much more, again depending on the features (read range, speed, accuracy and etc). As more and more companies are using RFID, the costs are dropping continuously, so you should keep an eye on this technology even if at the moment the cost is still too high for you.
So, would you be interested in using RFID? If you have any questions, please contact us at 781313 or kent at cpttm dot org dot mo.