I am working on bearing faults detection. I am doing the following steps:
signal->mean zero->high pass->hilbert->y->fft->cepstrum of y.
my code is:
analy = hilbert(Signal); y = abs(analy); N = 2*2048;T=N/Fs; sig_f = abs(fft(y(1:N)',N)); sig_n = sig_f/(norm(sig_f)); Signal_fft_hilbert = sig_n; freq_s = (0:N-1)/T; figure(3) plot(freq_s(2:250),Signal_fft_hilbert(2:250)) title ('Average FFT after Hilbert enveloping'); xlabel('Frequency in Hz') figure(4) c2=cceps(y(2:250)); plot(freq_s(2:250),c2)
The problem is I am not able to extract the fundamental frequency out of the spectrum or cepstrum. my bearing frequency is 42 Hz.I am not getting prominent peaks in this region. Please suggest something.