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There are beam-steerable phased-array antennas that can read a standard passive UHF RFID tag from about 600 feet. If you used a tag with an extra-large antenna, you could maybe get to 1,000 feet. There is no way to read a tag from a satellite. It is simply impossible.
It is like a balloon that you and I both hold together in our hands. I squeeze the balloon in Morse code, and you can feel the changes in the balloon and thus read the code. The size of this balloon is determined by the size of the loops in the reader and tag antennas, as well as the amount of energy. Generally speaking, you would not be able to read a tag from more than a few inches away, though if you had a really big loop in the reader antenna, you could get it up to a few feet.
Would the antenna show up on x-ray if it was made of ink as mentioned is possible in another post? If not, how would you detect one like that? I need a way to check regardless of the materials used or different ways to check for the various possibilities. Is there maybe a way to detect the energy signal as it travels to or from the chip?
Also could a mid-range military-grade drone hovering 50 to 100 meters overhead use it for tracking if it had the right equipment mounted under it?