利用FFT校正两个密集信号的频率和相位

Correction of Frequency and Phase of Two Overlapped Spectrum Signals Based on FFT

在一个频率分辨单元及其附近只存在一个频率信号时,对频率和初相的校正有多种方法,如三点卷积校正法、幅度比值校正法和相位差法。而在一个频率分辨单元及其附近存在两个频率信号时,上述方法均告失效。目前人们提出识别和搜索方式,但这种处理不利于快速计算。本文在分析相位差法和幅度法的基础上,给出了直接计算。仿真结果证明这一方法简单有效,而且可以推广到同一频率分辨单元存在两个以上频率信号的情况。

Many correction methods have been proposed tor signal＇s trequency and phase corrections when there is only a frequency signal in one frequency resolution cell, for example, three-point convolution method, amplitude ratio method and phase difference method. These methods can not be used when there are two frequency components in one frequency resolution cell. This paper presents a direct formula with FFT based on phase difference and spectrum amplitude, and gives Monte Carlo simulation results. The results show that the method is effective and can be extended to multi-frequency components case.