Matlab_fft画信号幅值谱 Fs=1000;% Sampling frequencyT=1/Fs;% Sampling periodL=1500;% Length of signalt=(0:L-1)*T;% Time vectorS=0.7*sin(2*pi*50*t)+sin(2*pi*120*t);Y=fft(S);plot([0:L/2]*Fs/L,abs(Y(1:L/2+1))/(L/2));%取半边谱,这里要求L是偶数title('Single-Sided...
% wc is the interval pulse; % to plot the amplitude spectrum: stem(wc,abs(ck)) %[wc,w0,a0,ak,bk,c0,ck]=get_harmoniques(y,pas) % be a signal x(t). % For more theorical details look athttp://www.azzimalik.com N=length(y); Y=fft(y); if size(Y,2)==1; Y=Y'; end ...
plot(t,X) title('Gaussian Pulse in Time Domain') xlabel('Time (t)') ylabel('X(t)') % To use the fft function to convert the signal to the frequency domain, % first identify a new input length that is the next power of 2 from the original signal length. % This will pad the s...
横轴表示频率,纵轴表示信号的幅度。以下是绘制频谱图的代码: 代码语言:txt 复制 frequencies = (0:N/2)*(fs/N); % 计算频率轴 plot(frequencies, X); % 绘制频谱图 xlabel('Frequency (Hz)'); % 设置横轴标签 ylabel('Amplitude'); % 设置纵轴标签 title('Spectrum of the Signal'); % 设置图标题 ...
function [X,freq]=centeredFFT(x,Fs) %this is a custom function that helps in plotting the two-sided spectrum %x is the signal that is to be transformed %Fs is the sampling rate N=length(x); %this part of the code generates that frequency axis ...
ylim([-1 1]); subplot 312; plot(time,signal,'k'); title(['带噪语音 SNR=' num2str(SNR) ...
plot(sfft_mag); % plot fft result 如果仔细观察,发现定点的值是50,而我们sin波形的正弦信号幅度是1啊。。这是matlab fft返回结果定义的问题,我们只需要除以用于fft运算的采样点个数的一半即可: fftpts=length(s); hpts=fftpts/2; % half of the number points in FFT ...
如果直接使用fft函数在input signal y 上面，你会得到一个double-sided 类似“Fourier transform“的图像,...
1．假设信号域为四舍五入，向量t为n维向量，则信号的离散采样周期为Ts＝1／fs＝四舍五入／（n－1），其中fs为采样频率。2．从上面的离散傅里叶公式，我们可以知道在使用FFT函数之后，我们仍然得到一个n维向量。3．频域长度定义为lenf，满足lenf＝（N－1）＊Ts，实体lenf＝（（N－1）＊（N－1...
subplot(2,1,1), plot((0:(NS-1))/NS*fe2, s1), grid title(‘Single-Sided Amplitude Spectrum of s(t)’) xlabel(‘Frequency (Hz)’) ylabel(‘|s(k)|’) x1 = abs(fft(x,NS)); subplot(2,1,2), plot((0:(NS-1))/NS*fe2, x1), grid ...