Title :
Cosine-modulated filterbanks based on extended Gaussian functions
Author :
Siohan, Pierre ; Roche, Christian
Author_Institution :
France Telecom, Cesson-Sevigne, France
fDate :
11/1/2000 12:00:00 AM
Abstract :
A new family of cosine-modulated filterbanks based on functions called extended Gaussian functions (EGFs) is obtained. The design is particularly simple since it is mainly based on a closed-form expression. Nearly perfect reconstruction cosine-modulated filterbanks are obtained as well as guidelines to estimate the filterbank parameters. This analytical design method can be used to produce, with a controlled accuracy, filterbanks with practically no upper limitations in the number of coefficients and subbands. Furthermore, a slight modification of the prototype filter coefficients is sufficient to satisfy exactly the perfect reconstruction constraints. An analysis of the time-frequency localization of the discrete prototype filters also shows that under certain conditions, EGF prototypes are at less than 0.3% from the optimal upper bound
Keywords :
Gaussian processes; channel bank filters; parameter estimation; time-frequency analysis; EGF; closed-form expression; cosine-modulated filterbanks; discrete prototype filters; extended Gaussian functions; filterbank parameters; nearly perfect reconstruction cosine-modulated filterbanks; prototype filter coefficients; time-frequency localization; Closed-form solution; Design methodology; Design optimization; Filters; Frequency; Guidelines; Parameter estimation; Prototypes; Speech; Upper bound;
Journal_Title :
Signal Processing, IEEE Transactions on