基于CZT的基波频率测量—更小运算量算法研究

Mensuration of Base Frequency Based on CZT——Arithmetic at Less Operation Study

由于周期信号的频谱是线谱,用FFT计算频谱时,需要设置采样频率是基波频率的整数倍,才能采样一个基波周期以最小运算量精确的计算出谐波幅度及相位.本文把CZT算法用于周期信号基波测量,提出了一种小点数多次CZT的运算方法,用4倍的基波频率采样,采样16点施加汉宁窗,合理设置计算路径,在估计的频率范围内求10点CZT,把求频谱的运算量集中在真实谱线附近,多次循环从粗测到细测逐步缩小计算范围提高精度,将计算误差控制在要求的范围内,最后把计算结果经过换算得到基波的频率.仿真结果说明该算法精度高,运算量小,优于直接FFT算法.

All around,frequency spectrum of period signal is linetype,while applying FFT Arithmetic in computing spectrum,sampling frequency is required to be integral times as base frequency.Harmonious computed accurately at less operation needs one period of base frequency.This paper applies CZT Arithmetic in mensuration of period signal s base frequency,an Arithmetic ——less number of operation and more times CZT—— was brought forward.For calculating base frequecy selecting sample frequncy which is 4 times of base f...