ECHO CANCELLER HAVING SPECTRAL ECHO TAIL ESTIMATOR

摘要

An echo canceller comprises a signal input for a far end signal, an audio input for a distorted desired signal, an echo estimator coupled to the signal input, and a spectral subtracter coupled to the echo estimator and the audio input. The echo estimator further comprises digital filter means covering a time span of at least a part of the echo to be cancelled. Spectral subtraction of the echo part does not make use of echo phase information. Consequently this saves memory and processing power of calculations made in the echo canceller. Furthermore these calculations are not restricted to a particular decaying course of the room impulse response, as any kind of echo tail course may be modelled. This provides a larger degree of freedom in practical embodiments and broadens the application area of the echo canceller.