Noise correction approach for pole-zero modeling by pencil-of-functions method

The paper describes very recent and promising results on a new approach to noise correction for pole-zero modeling of signals by the pencil-of-functions method. In contradistinction to spectral subtraction techniques where only amplitude information is emphasized (and phase is ignored), we propose a method that (a) estimates the noise spectral density for the frame, and then (b) performs the subtraction of the noise correlation matrix from the correlation matrix of the information signals. The information signals are, of course, generated by processing the test signal by a cascade of first-order low pass signals, as described in earlier papers. Improvement resulting from this noise correction technique is particularly remarkable when judged by the pole-estimation accuracy, A comparison of the poles for multiple noise runs for three methods, namely, (a) Prony method, (b) Pencil-of-functions method, and (c) Pencil-of-functions method with noise correction, is given. The signal considered was the impulse response of a third order rational filter H(z), masked by noise with an SNR=12 dB.