针对多速率信号处理中抽取和内插过程对信号频谱的影响进行研究, 利用傅里叶变换对整数倍抽取和整数倍零值内插后的信号频谱进行了理论推导, 得出抽取和内插后信号频谱的变化规律及避免频谱混叠的方法。通过仿真实验对整数倍抽取和整数倍零值内插后信号的频谱进行分析, 验证了理论推导的正确性, 最后说明了在多速率信号处理中应注意的问题。

This paper first studies the impacts of extraction and interpolation on signal spectrum in multirate signal processing. Then it theoretically derives the signal spectrum after integer times extraction and integer times zero-value interpolation by using the Fourier Transformation (FT), obtaining the regular pattern of signal spectrum after extraction and interpolation as well as the method for avoiding spectrum aliasing. In addition, it analyzes it in experimental simulation, verifying the correctness of the theoretical derivation. Finally it presents a few points for attention in multirate signal processing.