125kHz射频卡读卡器的天线设计

Design for the antenna of 125 kHz RF card- reader

125kHz射频卡读卡器的天线是射频卡读卡器的重要部分，关系到射频卡读卡器的可靠性和灵敏度．首先对125kHz射频卡天线的电流、磁场理论进行简要的分析，讨论读卡角度、读卡距离、天线线径和圈数与读卡器灵敏度的关系，寻求125kHz射频卡天线设计的一般方法，以最大限度地满足普遍要求的30—100mm读卡距离．

125 kHz antenna coil plays an important role which it is concerned with its feasibilities and sensitivity. in Radio Frequency Identification Card （RFID） reader, The paper analyzes the basic theories of current and magnetic fields of 125 kHz antenna coil, and studies the relations between the sensitivity of RFID reader and its orientation dependency, distance, wire type, resistance and size. The result shows that this 125 kHz antenna coil performs well for the general requirement of the identification range from 30 mm to 100 mm.