I need to develop a solution for determining whether an object/tag exists within a defined perimeter. The perimeter would be located indoors so GPS isn't an option. It would be an approx 10 metres x 10 metres rectangle. The 'tag' needs to fit in a person's pocket (however it could be battery powered), and I would need to know:

  1. When the tag leaves the perimeter (doesn't have to be exact and I don't care where it is located within the perimeter)
  2. Identify the tag left the perimeter (as there will be 10-20 objects in the perimeter that need to be tracked)

Would an active RFID system be the way forward? I'm thinking that I'd need 3-4 receivers spaced around the perimeter so that I can combine the readings from them to estimate the position.

Really appreciate any advice or suggestions.

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    I think there are some whitepapers about Bluetooth based indoor tracking. The ususal "How to find my lost key in the flat?" problem. Aug 6, 2017 at 20:17
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    Excepting very advanced "ultra wideband" time-of-flight schemes, deployed solutions tend to use receive signal level measurements, which are necessarily imprecise. BTLE beacons are indeed a common example, and if you can specify both the receiver and transmitter hardware, you'll be in somewhat better shape and the usual smartphone use case. Aug 7, 2017 at 4:20
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    Do you need location within the space (if so, what precision), or just presence/absence? How does this differ from a classical BLE problem? Please edit the question to clarify this... Aug 8, 2017 at 7:16
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    @Sean - presence/absence only. Location not required (point 1 in question). BTLE may be the best solution. I was also considering some sort of perimeter based 'gate' solution using RFID at the entry / exit points of the perimeter.
    – tpag26
    Aug 8, 2017 at 7:24
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    @tpag26 - I don't think your question clearly captures what you are asking (based on the comments). The question should stand on its own without comments, since comments get cleaned up over time on this site. Aug 8, 2017 at 7:43

2 Answers 2

  1. I have used EPC GEN2 [EPC865-868 MHz(Europe), 902-928 MHz(USA)] technology for an automated document management system. You can find long distance antennas on the market. For example - GAO RFID can be good choice.

  2. Tags supported by such a system can be found everywhere, including Alibaba.com and Amazon.com. Tags can be active or passive so you can choose what best fits you. Also, I recommend that you choose tags CPU/MEM size with care, because this can improve your solution's quality and/or features.

  3. Speaking of tags, there are on the market printers like ZEBRA which can print you out customized tags.


IF you would like to located indooer, rfid and bluetooth would be best choice. It has UHF and HF for rfid requency, respectively 860-960MHz and 13.56Mhz. And UHF divided into 902-928 MHz(USA) 865-868 MHz(EU). The passive rfid is better option than active if space not too big. I would recommend the SEIKO RFID for you, you will find more required information from the site.

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