| 摘要 |
This invention relates to an identification method and an identification apparatus for identifying an object that enters a certain zone, comprising transmitter means (1, 7, ANT) for generating a first electromagnetic field with a predetermined frequency in the zone, and measurement means (ANT, AMP, 2, 3, 6, 7) for measuring the first field in said zone. For accomplishing an apparatus reliable and immune to disturbances, the apparatus further comprises transmitter means (1, 7, ANT) for generating a second electromagnetic field of a predetermined frequency in said zone, the frequencies of the first and the second field deviating from each other, measurement means (ANT, AMP, 2, 3, 6, 7) for measuring the second electromagnetic field in said zone, and a control circuit (3) for comparing the values measured by the measurement means (3) with predetermined reference values, and for identifying, on the basis of said comparison, an object that enters the zone.
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