For a project on which I am working, I need to track the location of my finger tip when moving it on a table, so I require a precise solution consisting of small tags. What do you recommend? Is there any system better than RFID for this objective, such as Wi-Fi or Bluetooth?
—Saeed
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Dear Saeed,
Passive RFID systems can tell you that a tag is in range of a reader, but are unable to pinpoint an object’s precise location. Conventional active tags work the same way. When you pull up to a toll-collection booth, a passive signal awakens your vehicle’s tag, and it then begins broadcasting; you know only that a tag is in range of the booth’s interrogator.
Real-time location systems (RTLS) broadcast a signal every few seconds, and a variety of techniques can be used to locate a tag. Most active RTLS solutions can locate a tag only to within 10 feet. Ultra-wideband (UWB) is the most precise technology available, but it can only pinpoint a tag to within 1 foot.
I don’t know a lot about Bluetooth and Wi-Fi technologies, but I don’t believe they can pinpoint a tag as precisely as you require; they are designed for communication, not location. I’m sorry, but I’m unsure what system, if any, would work for your purposes.
If any of our readers have suggestions, please post them below.
—Mark Roberti, Founder and Editor, RFID Journal