| 摘要 |
A proximity reader (10) for a radio frequency identification (RFID) system is programmed using microprocessor (12) and peak detector (20) for determining and storing optimum antenna impedance values for tuning capacitors (22) to achieve peak antenna resonance at each of multiple operating frequencies generated by oscillator (18) and radiated by antenna (14). Antenna resonance is peaked at power up and periodically during operation to compensate for environmental detuning influences. The reader (10) scans the multiple frequencies to more efficiently search for off-frequency identification tags. |
