The system updates an autocorrelation function of the audio signal from samples in the audio signal, estimates {HEAD ~ an autocorrelation function} of {TAIL ~ the speech signal} from the updated autocorrelation function of the audio signal, and calculates a power spectral density of the speech signal using the estimated autocorrelation function 
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The system updates an autocorrelation function of the audio signal from samples in the audio signal , estimates { HEAD ~ an autocorrelation function } of { TAIL ~ the speech signal } from the updated autocorrelation function of the audio signal , and calculates a power spectral density of the speech signal using the estimated autocorrelation function
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH