Yes. Motorola has developed an ultrahigh-frequency (UHF) handheld RFID interrogator application that enables the device to increase its beeping as it gets closer to a tag for which it is searching (that is, as the tag’s signal strength increases). This would be useful, for example, for determining if a specific slide was in a particular cabinet, but it would not be possible to determine the precise location.
Companies have also developed high-frequency (HF) applications for tracking test tubes. This involves tagging the test tube, and situating an antenna under a specific slot in a test tube holder. A similar application could work for storing slides, helping you to narrow down the location considerably. The right solution really depends on the level of precision required for your particular application.
—Mark Roberti, Editor, RFID Journal
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