UHF RFID阅读器中恒定调谐增益LC-VCO设计

An LC-VCO with Nearly Constant KVCOfor UHF RFID Readers

设计了一种应用于UHFRFID阅读器的恒定调谐增益LC-VCO。VCO采用互补交叉耦合结构实现较高电源利用效率，偏置电路采用电压调节结构有效抑制电源引入的噪声。提出创新的分布式偏置容抗管阵列，以实现恒定调谐增益。电路采用TSMCO．18μmCMOSRF工艺设计。仿真结果表明，VCO的频率调谐范围为1．61～2．03GHz，在1MHz频偏处，相位噪声为-127dBc／Hz，电源电压1．8V，电路消耗的总电流为3．4mA。电路在保证低相位噪声和低电源噪声灵敏度的同时，工作频带内调谐增益的变化控制在±7%以内。

A monolithic LC voltage controlled oscillator （VCO） with nearly constant Kvco was designed for UHF RFID reader. In this circuit, a stacked NFET-PFET differential pair was used to achieve low phase noise with high power efficiency, and a voltage regulated bias circuit was employed to suppress power supply induced noise. A novel distributed biased varactor array was proposed to achieve nearly constant Kvco. The circuit was designed based on TSMC＇ s 0. 18 μm CMOS RF model. Results from simulation showed that the VCO achieved a wide tuning range from 1.61 GHz to 2.03 GHz, and a phase noise of -127 dBc/Hz at 1 MHz offset from 1.8 GHz carrier, and its Kvco variation was less than ± 7 % within operating frequency of interest. The circuit consumed 3. 4 mA of current from 1.8 V supply.