ACOUSTIC ECHO-CANCELER USING THE FBAF ALGORITHM

An acoustic echo canceler for teleconferencing systems is realized bas ed on the frequency bin adaptive filtering (FBAF) algorithm. In the FB AF algorithm, each frequency bin does an independent adaptive filterin g, so that parallel processing can be used to increase the throughput of the system. Hardware size can be reduced to about 25% of the FIR ti me domain adaptive filter (TDAF) requirement. The realized echo cancel er allows a confortable conversation with only 8 ms of delay. The hard ware prototype contains 12 VSP chips and one DSP chip. An ERLE (echo r eturn loss enhancement) of 30 dB was achieved using this prototype har dware for an echo reverberation path with 260 ms delay. An efficient m ethod for normalizing the convergence factor of the FBAF algorithm wit h a correlated input signal is given that speeds up the convergence ra te. The performance is shown by computer simulation.