摘要
针对吉尔伯特混频器电路转换增益和线性度低的问题,设计了一个高转换增益、高线性度下变频有源混频器,其电路跨导级采用电流镜结构和第三阶跨导系数消除结构,通过设置晶体管工作在不同的区域,使得晶体管的第三阶跨导系数相互消除,以提高电路的转换增益和线性度。电路采用TSMC 0. 18μm RF CMOS工艺。Cadence Spectre-RF软件仿真结果表明,在工作电压为1. 2 V、射频频率为5. 2 GHz、本振频率为5 GHz、中频频率为200 MHz时,所设计的混频器电路的转换增益为21. 9 d B,噪声系数为16. 5 d B,线性度(输入三阶交调点IIP3)为21. 68 d Bm,功耗为2. 3 m W,转换增益由典型指标10 d B提升至21. 9 d B,线性度由典型指标5 d Bm提升至21. 68 d Bm。可见,所设计的混频器电路的转换增益和线性度得到有效改善。
To solve the problem of low conversion gain and linearity in Gilbert mixer,a high conversion gain and high linearity down-conversion active mixer is designed.Current mirror structure and the third-order trans-conductance elimination structure are used to set the transistors working in different areas,so that the third-order trans-conductance coefficient can eliminate each other to improve the conversion gain and linearity of mixer.A mixer circuit is designed in TSMC 0.18μm RF CMOS process.Cadence Spectre-RF simulation results show that under the working voltage of 1.2 V,the radio frequency of 5.2 GHz,the local oscillator frequency of 5 GHz and the IF frequency of 200 MHz,noise figure reduces to 16.5 dB,with consuming power of 2.3 mW.The conversion gain increases from a typical specification of 10 dB to 21.9 dB while the linearity increases from a typical specification of 5 dBm to 21.68 dBm,which suggest that the designed mixer is effectively improved.
作者
李桂琴
宋树祥
岑明灿
刘国伦
谢丽娜
LI Gui-qin;SONG Shu-xiang;CEN Ming-can;LIU Guo-lun;XIE Li-na(College of Electronic Engineering,Guangxi Normal University,Guilin 541004,China)
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2018年第6期2184-2190,共7页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(61361011)
广西自然科学基金资助项目(2017GXNSFAA198363)
