TheechocancellerisbasedontheMDFalgorithmdescribedin:J.S.Soo,K.K.PangMultidelayblockfrequencyadaptivefilter,IEEETrans.Acoust.SpeechSignalProcess.,Vol.ASSP-38,No.2,February1990.WeusetheAlternativelyUpdatedMDF(AUMDF)variant.Robustnesstodouble-talkisachievedusingava