I am looking for the best medium-range (1 to 3 meter) miniature interrogator—ideally, one with its own battery power source. What would the experts suggest?
I am unaware of any reader that would fit your needs. A read range of 3 meters (approximately 10 feet) means you will need a passive ultrahigh-frequency (UHF) reader. There are many UHF interrogators on the market, but most are not "miniature," and most lack a power source. You will likely need to either choose one that is small, or that has a battery, or create something yourself.
ThingMagic offers its M5e-Compact UHF reader module, which is the size of a compact flash card. It consumes less power than larger readers, and has a read range of up to 6 meters (18 feet). It doesn't have a power source, but you could potentially add your own.
In addition, Motorola offers its RD5000 Mobile RFID Reader, which has an interrogator, an antenna and a battery housed in a ruggedized case, but that is not "miniature" either. It is seven inches long, nine inches wide and two inches deep—about the size of a netbook computer.
If RFID Journal's readers have any other suggestions, please post them below.
—Mark Roberti, Founder and Editor, RFID Journal
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