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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Ada libraries to deal with RFID tags
Date: Fri, 23 Dec 2022 20:38:42 +0200
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On 2022-12-23 19:23, Saada Mehdi wrote:
> 3 reading receiving towers should be able to triangulate/pin-point
> passive RFID chips at any given time.


You wanted 10 cm precision, right? If you use time-of-flight to compute 
the position, this requires about 0.3 ns timing precision and 
synchronization, if each Tx/Rx tower times its own sending and 
reception. You could get around the synch problem by cabling the Tx/Rx 
signals from and to a central Tx/Rx, but you still have to be able to 
measure the time differences between the three Rx signals to that 
precision. I doubt if that can be done with standard RFID Tx/Rx electronics.

Some discussion, negative and positive, here (part of the result of a 
web search for "RFID triangulation"):

https://www.quora.com/Can-the-position-of-a-RFID-tag-be-tracked-with-high-precision-in-a-2D-or-3D-space?share=1

There are some references to fancier electronics that can provide good 
spatial resolution.