An acoustic echo canceller for teleconference systems

We propose a parsimonious (economical) model of a room echo path as the cascade of a short FIR network and a long impulse response FIR filter in which almost-all the coefficients are kept to zero. The model automatically sets an efficient echo canceller structure. We also discuss an LMS coefficient updating method and give some simulation results for synthetically generated impulse responses. We think that its low complexity makes the processor attractive for use in hands-free telephony applications in which a (measurable) long impulse response must be compensated.