Title :
On Multiplicative Transfer Function Approximation in the Short-Time Fourier Transform Domain
Author :
Avargel, Yekutiel ; Cohen, Israel
Author_Institution :
Dept. of Electr. Eng., Technion-Israel Inst. of Technol., Haifa
fDate :
5/1/2007 12:00:00 AM
Abstract :
The multiplicative transfer function (MTF) approximation is widely used for modeling a linear time invariant system in the short-time Fourier transform (STFT) domain. It relies on the assumption of a long analysis window compared with the length of the system impulse response. In this paper, we investigate the influence of the analysis window length on the performance of a system identifier that utilizes the MTF approximation. We derive analytic expressions for the minimum mean-square error (MMSE) in the STFT domain and show that the system identification performance does not necessarily improve by increasing the length of the analysis window. The optimal window length, that achieves the MMSE, depends on the signal-to-noise ratio and the length of the input signal. The theoretical analysis is supported by simulation results
Keywords :
Fourier transforms; identification; linear systems; mean square error methods; transfer functions; transient response; MMSE; MTF; STFT; impulse response; linear time invariant system; minimum mean-square error; multiplicative transfer function approximation; short-time Fourier transform domain; system identification performance; Analytical models; Filters; Fourier transforms; Frequency estimation; Function approximation; Least squares approximation; Performance analysis; Signal to noise ratio; System identification; Transfer functions; Multiplicative transfer function; short-time Fourier transform; system identification;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2006.888292
