CAJ | 학술논문

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0.25 μm CMOS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100 kHz. 在2.645 GHz的射频输入下, 测试得到的转换增益为15.5 dB, 输入三阶交调点为-3.8 dBm,在中频1 M处的单边带噪声系数为9.2 dB.
침대령중빈접수궤적응용,제출료일충저조성、고증익적직접하변빈혼빈기,병용0.25 μm CMOS공예실현.저충혼빈기결구채용전류복용주입기술,병차재개관관적공원단병련료일개해진전감.전류복용주입제고료전환증익;해진전감소제료공원단적기생전용,억제료사빈신호적설루,감소료유간접개관궤리산생적섬삭조성.방진득도저개혼빈기수출1/f조성적괴점빈솔소우100 kHz. 재2.645 GHz적사빈수입하, 측시득도적전환증익위15.5 dB, 수입삼계교조점위-3.8 dBm,재중빈1 M처적단변대조성계수위9.2 dB.
A low noise,high gain direct down-conversion mixer is introduced for the zero-IF receiver application, and implemented in 0.25 μm CMOS process. Current reuse bleeding technique 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 capacitor 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.