摘要
针对单片雷达接收机中对低噪声放大器（LNA）的要求，采用CMOS0．18,um工艺设计了一个三级级联的镜像抑制低噪声放大器。通过在低噪声放大器中接入限波滤波器，实现对镜像信号的衰减，从而减小了后端混频器电路的设计难度。在ADS中对设计的放大器仿真，其结果为：最大供电电压为5V情况下，信号频段为3．0～3．2GHz，中频输出为225MHz，功率增益≥31dB，噪声系数（FN）≤O．5dB，1dB点的输入／输出功率分别为-19．5dBm和11．5dBm，对镜像信号的抑制度达22dB。
Three-level low-noise amplifier with image rejection was designed by the aid of the CMOS 0.18 btm technology to meet the requirement of the low-noise amplifier （LNA） in the radar receiver. With the notch filter in the LNA, it can reject the image signal which makes the circuit design of the mixer at the rear end easier. The designed amplifier is simulated in the ADS software. The simulation result is： under the condition of maximum supplied voltage 5 V, the band of the signal is 3.0 -3.2 GHz, IF output is 225 MHz, power gain ≥31 dB, noise figure 40.5 dB, input and output 1 dB, power of the points is -19.5 dBm and 11.5 dBm respectively and the rejection of the image signal reaches 22 dB.
出处
《现代电子技术》
2010年第12期5-7,共3页
Modern Electronics Technique
