一种小型化多协议超高频RFID读写器模块

A Miniaturized Multi-protocol UHF RFID Reader Module

设计了一种兼容国际标准ISO/IEC 18000-6C和中国标准GB/T 29768-2013的超高频射频识别读写器模块。基于定向耦合器的双调谐射频收发电路以紧凑的结构实现了较高的隔离度,降低了对接收前端电路的线性度要求。利用定向耦合器的耦合信号作为解调本振,以提高其与射频自干扰的相关性,降低下变频后的基带残留相位噪声。设计的读写器模块工作在920~925 MHz频段,饱和输出功率为29.6 d Bm,对6C和国标标签的盘存距离均超过15 m。读写器模块的小型化通过采用小尺寸的收发隔离电路和电路板的三维堆叠封装得以实现,其体积仅为70 mm×60 mm×15 mm。

An ultra-high frequency RF identification reader module is designed in this paper, which supports the international standard ISO/IEC 18000-6C and the Chinese standard GB/T 29768-2013. High isolation is achieved by a directional coupler based double-tuning RF transmit-receive circuit with a compact structure, which alleviates the linearity requirements of the receiver front-end. By utilizing the coupled signal from the directional coupler as the local-oscillation signal of the demodulator, the correlation between the local-oscillation signal and the RF self-jammer is improved, and the residual phase noise of the down-converted baseband signal is reduced. The designed reader module operates in 920-925 MHz band with a saturate output power of 29.6 dBm, and the inventory range is larger than 15 m for both the 6C tag and the Chinese standard tag. The miniaturization of the reader module is realized by using the compact transmit-receive isolation circuit and 3D stacked package printed circuit boards, and the volume is only 70 mm×60 mm×15 mm.