摘要
针对镜频和中频干扰对接收机性能影响的问题,分析了其原因并给出解决方案,设计了跟踪选频滤波器、逆切比雪夫陷波滤波器、5阶巴特沃斯低通滤波器,以及低噪声放大器的三级滤波方式所组成的短波接收机前端滤波放大电路,使短波接收机的中频、镜频抑制比均大于90 d B,接收机的性能得到较大提高。
The impact of IF( intermediate frequency) and image frequency interference on the receiver was discussed. Then the causes were analyzed and the solutions were given. The LNA( low noise amplifier) was designed. Three filtering methods were proposed for the shortwave receiver front- end filter amplifier circuit with tracking frequency selective filter,reverse Chebyshev notch filter,and 5- order Butterworth low- pass filter. The IF and image frequency rejection ratio of shortwave receiver were both realized to be greater than 90 d B.
出处
《武汉理工大学学报(信息与管理工程版)》
CAS
2015年第1期8-11,共4页
Journal of Wuhan University of Technology:Information & Management Engineering
关键词
中频抑制比
镜频抑制比
逆切比雪夫陷波滤波
巴特沃斯低通滤波
IF rejection ratio
image frequency rejection ratio
reverse Chebyshev notch filter
Butterworth low-pass filtering