由于加窗计算中衰减了原始信号的部分能量,因此对于最后的结果还需要加上修正系数。在线性谱分析中,一般使用幅度系数(amplitude correction),在功率谱中,一般使用能量系数(energycorrection)。(这段不清楚在实际中如何用) matlab中提供了很多窗函数,如下 还提供了显示窗函数的GUI工具,如wvtool可以显示用来显示窗的形状和...
Amplitude: Amplitude Correction is applied. It is used when the true amplitude of narrow band data is required. The Amplitude Correction Factor is defined as Power: Energy Correction is applied. It is used when the true energy level of the data is required. The Power Correction Factor is defi...
(0:L-1)*T; % Time vector Y = fft(S); %%% Amplitude correction P2 = abs(Y/L); P1 = P2(1:L/2+1); P1(2:end-1) = 2*P1(2:end-1); f = Fs*(0:(L/2))/L; %%% plot figure; plot(f,P1) title("Single-Sided Amplitude Spectrum of S(t)") xlabel("f (Hz)") ylabel...
3 Commits .gitattributes Initial commit Mar 24, 2022 README.md Update README.md Mar 26, 2022 fft.py readme Mar 24, 2022 README FFT fft, window function, Amplitude correction 1.原理 参考知乎专栏文章或视频:https://www.zhihu.com/column/c_1481725623442128898 ...
FFT后的N点复数,第一点表示直流分量(0Hz),而最后一点的下一点(实际不存在,假设为第N+1点)表示的频率为采样频率(Fs),这中间被N-1个点平均分为N等份,每点频率依次增加。例如,第k点所表示的频率为:FK=(K-1)Fs/N。所以FFT所能达到的频率分辨率为Fs/N。
In connection with two main errors of FFT spectrum computation: energy leakage and picket-fence effect,when using spectral window functions of rectangular and flat top windows cooperatively to do amplitude spectrum correction with TMS320F2812 DSP as control and process core of system,the peak data ...
% convert amplitude spectrum to dB (min = -120 dB) %将幅值转换成分贝有函数是ydb=mag2db(y),这里直接算 STFT_X = 20*log10(STFT_X + 1e-6); %时间轴 STFT_t=(nsc/2:(nsc-nov):nsc/2+(coln-1)*(nsc-nov))/Fs; %频率轴
ylim([-1,1]);xlim([0N/2]);grid subplot(5,1,5);stem(aa,'.');title('amplitudecorrectionspectrum');ylim([0,1]);xlim([0N/2]);grid r=round(f1)%求谱线个数 disp('频率校正值') fff=floor(f1)+ee(r+1) disp('振幅校正值') aaa=aa(r+1) disp('初相位校正值') ppp=p2(r+1)
For more information on window correction factors for amplitude and energy, see the article from Siemens,Window Correction Factors. Signal TypeWindowFrequency ResolutionSpectral LeakageAmplitude Accuracy Sinusoid (when amplitude accuracy is important)Flat TopPoorGoodBest ...
ylabel('Amplitude') text(0.005, 0.08, 'Choose a peak and frequency') 댓글 수: 2 Walter Roberson 2020년 2월 25일 "Sampling frequency is 20KHZ" No it is not. If you examine the times in the first column, the difference is 0.0005 which is 2kHz. Your Ts is not correct ...