基于立方卷积插值的信号DFT频谱校正算法

Correction Algorithm of DFT Spectrum Based on Cubic Convolution Interpolation

由于栅栏效应的存在,会使得基于信号DFT谱峰搜索的测频算法产生很大误差,因此在测频之前一般需对信号的DFT频谱进行校正。推导出用于单正弦信号DFT频谱校正的立方卷积插值核函数、插值函数及形状参数,并依据脉冲雷达信号是无数个正弦信号之和的事实,将其推广至脉冲雷达信号DFT频谱的幅度校正,给出其频谱检测算法。

Because of existing fence effect, the frequency measurement algorithm based on DFT spectrum peak of signal will produce geatly error, so the correction to DFT spectrum of signal is necessary. The interpolation kernel function and interpolation of correction algorithm of single sine signal based on cubic convolution are derived and shape parameter is determined via simulation. According to the fact of pulse radar signal is constituted of countless sine signals, analysis and correction algorithm of DFT spectrum of pulse radar signal is derived.