射频前端CMOS有源混频器的设计  

Design of RF front-end CMOS active mixer

作　　者：李桂琴 宋树祥[1] 岑明灿 刘国伦 张泽伟 LI Guiqin;SONG Shuxiang;CEN Mingcan;LIU Guolun;ZHANG Zewei(College of Electronic Engineering,Guangxi Normal University,Guilin 541004,Guangxi Zhuang Autonomous Region,China)

机构地区：[1]广西师范大学电子工程学院,广西桂林541004

出　　处：《电子元件与材料》2018年第9期57-62,共6页Electronic Components And Materials

基　　金：国家自然科学基金资助项目(61361011);广西自然科学基金项目(2017GXNSFAA198363)

摘　　要：混频器是射频前端电路中的一个重要模块。设计了一个低电压高增益的下变频混频器,对混频器经典的吉尔伯特电路结构进行了改进,采用跨导系数修正技术、电流注入结构提高混频器的增益、噪声和线性度性能,并且在跨导级的漏极端口并联了一个电感,消除寄生电容,减小间接开关机理闪烁噪声。本电路采用TSMC 180 nm RF CMOS工艺,在1. 2 V的工作电压下,Cadence软件仿真验证表明,射频频率为2. 4 GHz,本振频率为2. 39 GHz,中频频率为10 MHz时,所设计的混频器的转换增益为28. 4 d B,噪声系数为8 d B,线性度(输入三阶交调点IIP3)为10 d Bm,功耗为6. 86 mW,混频器的整体性能指标均得到了提高,满足射频前端的应用需求。Mixer is an important module in RF front-end circuit.A low-voltage and high-gain down-conversion mixer was designed which was based on the modification of classic mixer Gilbert circuit.Trans-conductance coefficient modification technology and current injection structure were used to improve the mixer’s gain,reduce the noise and enhance the linearity performances.Besides,an inductor was paralleled in the trans-conductance drain port,which could eliminate the parasitic capacitance and reduce the flicker noise causing by indirect switching mechanism.The mixer circuit was designed and simulated in TSMC 180 nm RF CMOS process.Cadence simulation results show that under the working voltage of 1.2 V,the mixer obtains a conversion gain of 28.4 dB,the noise figure is 8 dB,the linearity(input third-order intercept point IIP3)is 10 dBm and the consumption is 6.86 mW when the radio frequency is 2.4 GHz,the local oscillator frequency is 2.39 GHz and the IF frequency is 10 MHz.The performance metrics of mixer is improved which can satisfy the application requirements of RF front-end.

关 键 词：混频器 跨导系数修正技术 吉尔伯特 电流注入 转换增益 线性度 

分 类 号：TN773[电子电信—电路与系统]