UHF RFID芯片内置低误差低调制深度ASK解调器  

Low error and low modulation depth ASK demodulator for UHF RFID chip

作　　者：李青龙 徐勇 李峤 彭堃 张显 LI Qinglong;XU Yong;LI Qiao;PENG Kun;ZHANG Xian(School of Communication Engineering,Army Engineering University of PLA,Nanjing210007,China)

机构地区：[1]陆军工程大学通信工程学院,江苏南京210007

出　　处：《电子元件与材料》2021年第10期1040-1046,共7页Electronic Components And Materials

基　　金：国家自然科学基金(U1531124)。

摘　　要：针对幅值变化范围大和多种调制深度、多种速率的超高频射频信号,设计了一款由检波、限幅、均值产生电路和比较器构成的低误差ASK信号解调器。采用倍压整流和低通滤波技术并使用二极管连接型MOS器件,以简单结构实现了无源检波限幅;均值产生器运用峰值和谷值检测技术生成平均值电压,按接收能量大小确定参考值;利用比较器正反馈MOS管宽长比的差异形成迟滞特性,有效增强电路噪声抑制力。解调器采用TSMC 0.18μm标准CMOS工艺实现。仿真与流片测试结果表明,可处理的ASK信号调制深度低至30%,最大脉宽解调误差仅为0.43%。该解调器适用于符合ISO/IEC 18000-6C和GB/T 29768-2013协议的无源超高频射频识别(UHF RFID)标签芯片。To address the characteristics of wide amplitude variation,various modulation depths and rates of UHF RFID signals,a low-error ASK signal demodulator was designed,which was composed of detector,limiter,average generator and comparator.Using voltage doubler rectification and low-pass filtering technology combined with diode-connected MOS devices,the passive detector and limiter were realized with a simple structure.Using peak-valley value detection technology,the average generator determined the reference values according to the received energy.The hysteresis characteristic was obtained due to different width-length ratio of the MOSFETs on the positive feedback path of the comparator,which effectively enhanced the noise suppression.The circuit was implemented using TSMC 0.18μm standard CMOS process.Simulation and chip measured results show that the processible modulation depth for the ASK signal can be as low as 30%,and the maximum pulse width demodulation error is only 0.43%.It is suitable for passive UHF RFID tag chips that comply with ISO/IEC 18000-6C and GB/T 29768-2013.

关 键 词：RFID ASK 解调器 检波 平均值 迟滞比较器 

分 类 号：TN432[电子电信—微电子学与固体电子学]