Algorithm 2 Improved Subspace Algorithm

Step 1) Update the AR coefficients and variance of noisy signal during the speech-absent frame.

Step 2) Construct the whitening matrix using the estimated AR coefficients, and whiten the noisy signal by using.

Step 3) Compute the covariance matrix of the whitening noisy signal.

Step 4) Compute the eigenvalue and eigenvector of.

Step 5) Estimate the clean speech signal by using (12).