一种镜像频率抑制方法研究  

A New Method to Image-Rejection

作　　者：雷霖[1,2] 罗浚溢[1,2] 田书林[2] 

机构地区：[1]成都大学电子信息工程学院,四川成都610106 [2]电子科技大学自动化工程学院,四川成都611731

出　　处：《电气自动化》2013年第3期102-105,共4页Electrical Automation

基　　金：国家自然基金支持项目(60827001)

摘　　要：针对实际采样中往往有对镜像频率进行抑制的需要,提出了一种基于广义逆的镜像频率抑制系统,利用周期非均匀采样的时间延迟为采样信号的中心频率的四分之一时两通道相位差为■90°的特点,借助联合子空间理论把镜像频率抑制的过程转换为矩阵向量运算,通过广义逆就可以得到抑制的信号;由于采样通道的失配误差,提出了一种前向固定式误差补偿方式;并与传统的镜像抑制方式进行了比较得出了提出的方法在抑制效果等方面都好于传统方式。A new method of the image frequency suppression based on generalized inverse is proposed in this paper.According to the features of periodic non-uniform sampling that the phase difference of two channels equals as the time delay is 1/4 fc,the suppression of the negative frequency band is transformed into matrix and vector operations by using the theory of union of subspaces.However,the image attenuation alone is clearly insufficient for band-pass signals.To enhance this obtainable image attenuation,an interference canceller of error compensation structure is proposed.The conclusion shows the frame-work presented here is better than the traditional method.

关 键 词：广义逆 联合子空间 矩阵运算 镜像抑制 误差补偿 

分 类 号：TM933[电气工程—电力电子与电力传动]