Ali Gharamohammadi - PhD student, Electrical engineering, Sharif university, Enghelab avenue, Tehran, Iran.
Mohammad Taghi Mehrabani - PhD, Mechanical engineering, Ava Sanjesh Aras, Inc., Enghelab avenue, ۱۴۵۸۸۸۸۴۸۱,Tehran, Iran.
Abouzar Abbasi - MsC, Mechanical engineering, Ava Sanjesh Aras, Inc., Enghelab avenue, ۱۴۵۸۸۸۸۴۸۱,Tehran, Iran.

In this paper, in order to remove motor harmonics from speech signals, a hybrid algorithm consists of a whitening method and infinite impulse response (IIR) filter is proposed. The combination of these methods results better harmonic suppression than alone filter. In spite of the fact that the output of the whitening is very similar to input, it should make the covariance matrix unit diagonal. The results shows that signal to noise (SNR) is improved by 1.9 dB.

Harmonic suppression; Whitening; IIR adaptive filter.