摘要 |
A transponder for automatic identification and corresponding systems. The transponder may include patch antennas for reflecting transponder data as information sidebands of a microwave signal received from a reading unit, for example. The antennas may by parallel to, but oppositely directed from one another. Additionally the antennas may act against at least one intermediate earth plane, and are linearly polarized so that their polarization direction is rotated through 90° in relation thereto. In this arrangement, the transponder may be read from a short distance and from both sides of the antennas, and communication with the transponder may not be disturbed by the presence of a rearwardly-located reflection plane.
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