A real-time acoustic echo cancellation system

The algorithms and implementation of an adaptive acoustic echo canceler using a single WE DSP16A digital signal processor are described. A subband approach is used to enhance the overall system convergence rate. Two adaptive transversal filters based on the normalized leaky least-mean-square adaptation algorithm are implemented in the two subbands with the decimated subband digital signals. A double talk detector and a residual echo suppressor are implemented on the processor. When the DSP16A operates at 60 MHz, the canceler offers sufficient echo cancellation in rooms with reverberation times of up to 250 ms