| 摘要 |
<p>In an RFID reader/writer (50), a transmitted signal generation unit (1) generates a carrier wave formed by circular polarization. A first antenna (6A) transmits and receives a polarized wave of a first polarization component. A second antenna (6B) transmits and receives a polarized wave of a second polarization component orthogonal to the first polarization component. When a signal analysis unit (9A, 9B) receives a reflected wave from a plurality of tags for the carrier waves by the first and second antennas (6A, 6B), the unit (9A, 9B) analyzes the first and second polarization components contained in the reflected wave. Based on the analysis result of the signal analysis unit (9A, 9B), electric power to be transmitted from the first and second antennas (6A, 6B) is set to control the polarized wave of a transmission wave to be transmitted with a command to a plurality of tags.</p> |
