Hi friends,
Recently I'm very interested in RFID, however I need some more information. In particular, I'm curious to know what an RFID reader can tell.
I heard that it can locate the RFID tags. Does it really locate the tag, or does it just tell you the tag with x feet of distance?
If you can supply me with more information, it would be great. Thanks!
Kelvin,
In essence, an RFID reader simply tells you the ID (7 digit id) of all tags in the read zone that have responded to its request. It has no knowledge of the distance or precise location, just that the tag is currently positioned somewhere within range. The reader broadcasts a signal on a particular frequency, say 13.56 MHz. When a tag in the read zone collects enough energy from the broadcast, it backscatters (reflects back) and responds with data such as its tag id.
You need a reader/writer, transmit and receive antenna and the tags. Each tag has an antenna and integrated circuit built in including capacitors to store the charge it needs to power the transmission.
Tags can be passive or active. A passive tag simply reflects back its factory programmed id. An active tag is battery powered, can be used to return data that has been programmed in and generally has a longer range and is more reliable.
You should visit Wikipedia
If there are no tags present the RF field will read your brain and report the contents, or lack thereof, to the government ;-)
...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
gLOL!
Best regards,
Max
-- Maximilian Becker http://www.chipspace.net - Electronics Information & News
Thanks, that's very helpful!
Regards, Kelv> Kelvin,
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.