amplitude spectrum

hi, how do i plot the amplitude spectrum of speech segment with a given sampling frequency fs, a given length and known number of bits. thanis in advance

Answer 1

[Wayne King]

There are a couple things you can do. Let x be your speech signal and fs your sampling frequency. The following two are power estimates.

    plot(psd(spectrum.periodogram,x,'Fs',fs));

If you do not want it in dB:

    psdest = psd(spectrum.periodogram,x,'Fs',fs);
    plot(psdest.Frequencies,psdest.Data);
    xlabel('Hz'); grid on;

Finally, just using fft()

      xdft = fft(x);
      % assume x is even length
      xdft = xdft(1:length(x)/2+1);
      freq = 0:fs/length(x):fs/2;
      plot(freq,abs(xdft));
      xlabel('Hz');

[deji]

thank u very much..

[deji]

is the power spectral density estimate the same thing as the amplitude spectrum.. what i just read about it now shows to be something else