Patent ID: 8451096

Claim:
An RFID read/write station, comprising: read/write equipment having— a transmitter, a receiver, a processor unit, and at least one read/write antenna; a first passive electronic tag at a fixed location relative to the transmitter and receiver coupled via a first coupling element to an output of the transmitter and to an input to the receiver, wherein the first coupling element has a first pre-set coefficient of coupling, and further wherein an expected strength of a signal received via the first coupling element from the first passive electronic tag is known, and a second passive electronic tag at a fixed location relative to the at least one read/write antenna coupled to the at least one read/write antenna via a second coupling element, wherein the second coupling element has a second pre-set coefficient of coupling, and wherein the RFID read/write station is configured to periodically or aperiodically monitor itself by— identifying the first and second passive electronic tags, reading data stored in first and second passive electronic tags, or both identifying the first and second passive electronic tags and reading data stored in first and second passive electronic tags.