Could the reader’s power be turned down to scan a small number of vehicles? An enforcement vehicle would then drive around slowly, taking reads.
I have not heard of anyone using vehicle-mounted readers to interrogate tags embedded in RFID permits. If you use ultrahigh-frequency (UHF) transponders designed for windshields, you should have no problem reading these from a vehicle traveling at, say, 15 miles per hour. There are a number of companies, such as William Frick and Co., that make tamper-proof stickers built to be affixed to windshields.
—Mark Roberti, Founder and Editor, RFID Journal
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