This kind of question really bugs me.
No, I’m kidding. I couldn’t resist making a pun.
There are RFID systems available that can read tags from a distance of 1 meter (3.3 feet), 10 meters (33 feet), 300 meters (984 feet) and more. The problem is that the longer-range systems require a tag with a battery, which would probably be a tad heavy for the average fruit fly.
Passive ultrahigh-frequency (UHF) systems, which can read tags from 10 meters away, require a large tag antenna to achieve that kind of read range (usually measuring about 8 inches in length). As you shrink the antenna, the read range decreases accordingly. A tag that could be used on an insect would require the antenna to be etched onto the chip, which is possible—but the read range would be only about 1 centimeter (0.4 inch), which would obviously not be very useful for your purposes.
As such, I don’t think it’s possible to create a tag small enough and light enough to be used on an insect for tracking it at a distance of 1 to 2 meters. If any of our readers have information to the contrary, however, please post details below.
—Mark Roberti, Founder and Editor, RFID Journal
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