设计了一种低功耗高线性度的新型超高频射频识别射频前端电路.在LNA的设计中,通过在输入端采用二阶交调电流注入结构以提高线性度,在输出端采用开关电容结构以实现工作频率可调;在混频器的设计中,在输入端采用同LNA相同的方法以提高线性度,而在输出端采用动态电流注入结构以降低噪声.该电路采用0.18μmCMOS工艺,供电电压为1.2V,仿真结果如下:输入阻抗S11为-23.98dB,IIP3为5.05dBm,整个射频前端电路的增益为10dB.
This paper mainly introduced the UHF RFID RF front end circuit design.In the LNA design,it improved the linearity by using the 2nd-intermodulation injection structure at the input terminal,and achieved the operating frequency adjustable by using switch capacitor at the output terminal;in the mixer design,it improved the linearity by the same way as LNA,and eliminated the noise by using dynamic current injection structure at the output terminal.The circuit has been fabricated with a 0.18 μm CMOS process,the supply voltage is 1.2 V,the simulation results show that:the impedance matching S11 is-23.98 dBm,IIP3 is 5.05 dB,and the overall conversion gain of the front end circuit is 10 dB.