一种改进的基于相位差法的频谱校正方法

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振动与冲击 ›› 2012, Vol. 31 ›› Issue (1) : 162-166.

论文

一种改进的基于相位差法的频谱校正方法

胡文彪;夏立;向东阳;吴正国

作者信息 +

A modified frequency spectrum correction method based on the phase difference correction method

HU Wen-biao; XIA Li; XIANG Dong-yang; WU Zheng-guo

Author information +

文章历史 +

摘要

采用相位差校正法进行频谱校正，对幅值进行校正需要依赖于窗函数的谱函数。而实际上很多窗函数都十分复杂，其谱函数的解析表达式难以取得。该文提出基于相位差法取得频率修正量后，可以将原加窗序列乘以一个由频率修正量产生的复数序列，相当于进行一个小的频移，产生一个新的序列。新序列的信号频率正好对准离散频谱上的某一根谱线，不会产生泄漏。因此在幅值校正时不需要依赖窗函数的谱函数，通用性好。仿真研究和应用实例表明，采用该文提出的方法，选择合适的窗函数，即使是密集分布的频谱，也可以达到理想的校正精度

Abstract

Amplitude correction can not void dependence of the spectrum functions of window functions, when the phase difference correction method is employed to correct frequency spectrums. However certain window functions are very complex actually and the analytic expression of their spectrum function can’t be obtained. This paper proposed a novel amplitude correction method. After frequency correcting value is calculated based on the phase difference correction method, a new numerical sequence can be obtained by multiply the primary sequence and a plural sequence which is produced by the frequency correcting value. Then signal frequency of the new plural sequence aims at a certain spectral line, and frequency spectral analysis doesn’t produce the leak of the frequency spectrum. So the amplitude correction doesn’t depend on the spectral functions of window functions. Computer simulation results and the application example demonstrate that we can achieve the ideal correction precision even if in the dense distribution frequency spectrum by using the method which this paper proposed and choosing the appropriate window function.

导出引用

胡文彪;夏立;向东阳;吴正国. 一种改进的基于相位差法的频谱校正方法[J]. 振动与冲击, 2012, 31(1): 162-166

HU Wen-biao;XIA Li;XIANG Dong-yang;WU Zheng-guo. A modified frequency spectrum correction method based on the phase difference correction method[J]. Journal of Vibration and Shock, 2012, 31(1): 162-166