基于TDSPSL的新型宽带RFID近场天线研究

A Novel Broadband RFID Near-Field Antenna based on TDSPSL

提出一种适用于超高频射频识别系统的宽带近场天线。天线由环状偶极子、天线馈线及金属反射板构成,总体尺寸为300 mm×300 mm×21.6 mm。天线馈线采用锥形渐变双边带状线(Tapered Double-side Parallel Strip Line,TDSPSL),并在其间进行电阻加载,以扩展带宽使得天线具有水平全向低增益。通过相关参数优化,在较大范围内获得了较为均匀的磁场分布。实测结果与仿真结果吻合较好,且S_(11)小于-10 dB带宽为277 MHz(790~1067 MHz),覆盖了RFID全球频段。该天线对于电感及电容耦合型标签,具有良好的近场读取效果。

A broadband near-field antenna for UHF RFID system is proposed. The antenna is consisted of annular dipoles, feeding unit and reflective plate,with an overall size of 300 mm×300 mm×21.6 mm. The antenna feeder uses a TDSPSL（Tapered Double-side Parallel Strip Line） with resistive loading in between, thus to extend the bandwidth so that the antenna has a horizontal omni-directional low gain. Through the optimization of relevant parameters, a relatively uniform magnetic field distribution is acquired within a relatively large range. The actually measured results are in good agreement with the simulation results. The bandwidth is 277 MHz（790 to 1067 MHz） when S_（11） is less than-10 dB, covering RFID global frequency band. The antenna has a good near-field reading effect for inductive and capacitively coupled tags.