摘要
介绍了一种用于蓝牙低中频接收机的镜像抑制电路 ,包括改进的吉尔伯特型混频器 (采用折叠级联输出 )和跨导 电容复数滤波器 ,二者利用电流信号直接耦合 .整个电路用TSMC 0 35 μm单层多晶硅CMOS数字工艺实现 .仿真和测试结果表明 :镜像抑制比大于 2 0dB ,满足蓝牙接收机的要求 ,整个电路使用 3 3V电源供电 ,功耗约为 2 7mW .
Image rejection circuit for bluetooth low intermediate frequency receiver is described.It includes modified Gilbert mixer (using folded-cascode output) and G m-C complex filter,and direct current coupling between mixer and filter is realized.The chip is fabricated with TSMC 0.35μm,single-poly CMOS digital technology.The simulation and measurement results show that the image rejection ratio IMRR>20dB and the requirement of the bluetooth receiver is satisfied.The circuit consumes 27mW under the supply voltage of 3.3V.
关键词
蓝牙
接收机
镜像抑制
bluetooth
receiver
image rejection
