Algorithm design of a stereophonic acoustic echo canceler system

A software program has been designed that successfully runs a stereophonic acoustic echo canceler natively on a personal computer. This is a major achievement since an echo canceler requires that the soundcard's input and output signals are time-synchronous. Synchronizing the audio streams is a great challenge in such an "asynchronous" environment as the operating system of a PC. Furthermore, stereophonic echo cancellation is significantly more complicated to handle than the monophonic case because of computational complexity, nonuniqueness, and convergence problems. Special care has to be taken in the algorithm design. This work presents the core algorithms, i.e., the adaptive algorithm and the double-talk detection algorithm of the implemented echo canceler.