超高频标签芯片整流器整流效率是影响标签通信距离的主要因素之一。目前常用的商用标签并未留有测试端口,封装后采用探针测量芯片电路方法不再适用。基于超高频无源射频识别(UHF-RFID)通信原理和整流器工作原理,导出UHF-RFID标签芯片整流电路效率与芯片阻抗之间的关系式,提出标签芯片整流电路效率的无线测量方法。实验结果表明,当芯片输入功率在[?18,?13]dBm内时,芯片整流效率小于46%,无线测量结果与探针测量和仿真结果基本一致,误差小于4.8%,且无线测量方法无需破坏标签封装结构。
The rectification efficiency of rectifier in UHF tag chip is one of the main factors affecting the communication distance of the tag.Currently many commercial tags do not have the test ports,hence the probe measurement method is no longer applicable for the test of tag chip.Based on UHF-RFID wireless communication principle and the rectifier works principle,a comparison relationship between UHF-RFID chip impedance and rectification efficiency was provided.Then awireless measurement method for rectification efficiency of rectifier in UHF tag chip was proposed.It is shown that,when the input power of chip is within[?18,?13]dBm,the results of wireless measurements are basically same as those of theoretical analysis and probe measurements,where the rectification efficiency is less than46%and the error is less than4.8%.Compared with the probe measurement,the wireless measurement method need not to destroy the encapsulation structure of tags.