Sparkfun
Topics: Passive, Active, Active RFID
Transcript Except
Rob Reynolds talks about rfid. Rfid is an acronym for radio frequency identification and is part of a group of technologies along with things like barcodes called aidc or automatic identification and data capture. rfid is used for things like id badging and controlling access to restricted areas for asset tracking and inventory management race timing pet identification even counterfeit prevention in the pharmaceutical industry. rfid has been with users in one form or another since the mid-1940s with things like theremin’s listening device as well as identification friend or foe transponders used in aircrafts during World War two. now 75 years later users have a whole host of options when it comes to rfid. rfid is basically broken up into three components. there’s the tag, the reader and the computer or controller that does all the brain work. as far as the tags go users got three options there are active tags and those are tags that have their own power source usually a battery and can continually transmit their signal. user will find active in things like your ez pass or express toll the things users stick in users’ car and then they just read toe as car go down the highway. there are passive tags have no power source rather they rely on the rf energy transmitted from the reader to send their signal and the third type is semi-passive now like passive tags they require the energy from the reader to send their signal however they do have a battery like the active tags but in the case of semi-passive tags that battery is usually only used to power a sensor and the associated circuitry as far as readers go they generally fall into three ranges there’s low frequency high frequency and ultra-high frequency. now while all these possibilities are great and allow users to really customize project to exactly how user need it for those just starting out in rfid they can lead to some unintended issues. for example, if users were to get rfid quick kit put it all together build a great project that users love, user want to get more tags for it, but user want small ones if users were to go with the Mayfair classic laundry tag because they’re small they’re not going to be compatible with this because those are 13.56 megahertz tags, and this is a 125khz reader.
