一种低噪声、高增益的直接下变频混频器  

A Low Noise,High Gain Direct Down-conversion Mixer

作　　者：高海军[1] 郭桂良[1] 阴亚东[1] 杜占坤[1] 阎跃鹏[1] 

机构地区：[1]中国科学院微电子研究所电子系统总体技术研究室,北京100029

出　　处：《固体电子学研究与进展》2009年第4期488-493,共6页Research & Progress of SSE

摘　　要：针对零中频接收机的应用,提出了一种低噪声、高增益的直接下变频混频器,并用0.25μmCMOS工艺实现。这种混频器结构采用电流复用注入技术,并且在开关管的共源端并联了一个谐振电感。电流复用注入提高了转换增益;谐振电感消除了共源端的寄生电容,抑制了射频信号的泄漏,减小了由间接开关机理产生的闪烁噪声。仿真得到这个混频器输出1/f噪声的拐点频率小于100kHz。在2.645GHz的射频输入下,测试得到的转换增益为15.5dB,输入三阶交调点为-3.8dBm,在中频1M处的单边带噪声系数为9.2dB。A low noise,high gain direct down-conversion mixer is introduced for the zero-IF receiver application, and implemented in 0.25μm CMOS process. Current reuse bleeding tech- nique is adopted, and an inductor is added at the common source node of the switching pairs. The current reuse bleeding increases the conversion gain. The inductor eliminates the parasitic capaci- tor at the common source node, so the RF current leakage is suppressed and 1/f noise caused by indirect switch mechanism are reduced. Simulation result shows that the corner of 1/f noise at the mixer output is lower than 100 kHz. Under 2. 645 GHz RF input, the measured conversion gain is 15.5 dB, the input third-order intercept point is -- 3.8 dBm. The SSB noise figure at 1 MHz IF is 9.2 dB.

关 键 词：混频器 闪烁噪声 直接下变频 电流注入 吉尔伯特单元 

分 类 号：TN773[电子电信—电路与系统] TN405