10. An echo suppression method for a speech input dialogue system, said speech input dialogue system producing a system input request and receiving an input speech signal, said method comprising the steps of: fast Fourier transforming each of said system input request and said input speech signal for producing a short-term magnitude spectrum of said system input request and a short-term magnitude spectrum of said input speech signal each of said short-term magnitude spectra being comprised of frequency components; band reducing said short-term magnitude spectrum of said system input request and said short-term magnitude spectrum of said input speech signal, by dividing said short-term magnitude spectrum of said system input request into a first set of sub-band signals based on said frequency components of said short-term magnitude spectrum of said system input request, and for dividing said short-term magnitude spectrum of said input speech signal into a second set of sub-band signals based on said frequency components of said short-term magnitude spectrum of said input speech signal; simulating, in a plurality of adaptive filters supplied with said first set of sub-band signals, a pulse response of a line echo, produced by said system input request, on a path traversed by said input speech signal, said plurality of adaptive filters respectively having adaptation coefficients; adapting said adaptation coefficients dependent on respective outputs of said adaptive filters and on said second set of sub-band signals; restoring a full-band signal from said outputs of said plurality of adaptive filters to replicate said line echo; and subtracting the replicated echo from said short-term magnitude spectrum of said input speech signal.
17. A method as claimed in claim 10 comprising the additional step of supplying a result of the step of subtracting to a speech recognition system.