Synthesized Stereo Combined with Acoustic Echo Cancellation for Desktop Conferencing

One promising application in modern communications is desktop conferencing which can involve several participants over a widely distributed area. Single-channel sound is clearly not enough for a listener to distinguish one remote talker from another. Moreover, it will be very hard to understand two (or more) remote persons talking at the same time. Synthesized stereo sound will definitely help a great deal to solve these problems. We suppose that we are in a hands-free environment where the composite acoustic signal is presented over loudspeakers, thus requiring acoustic echo cancellation. In this memo, we explain the most useful ways to synthesize stereo sound and how this can be combined in an efficient manner with stereo acoustic echo cancellation in the face of several difficult problems.