Real-valued Delayless Subband Affine Projection Algorithm for Acoustic Echo Cancellation

Abstract- Acoustic Echo Cancellation (AEC) often involves adaptive filters with large numbers of taps, which results in poor performance in real-time applications. The utilization of Delayless Subband Adaptive Filter (DSAF) helps reduce com-putations and improve the overall performance. However, conventional oversampled subband adaptive filters mainly use DFT or GDFT based analysis/synthesis filter banks and gener-ate “complex-valued ” subband signals. This is particularly inefficient when applying the Affine Projection Algorithm (APA), a popular adaptive algorithm for AEC problem, to each subband. For APA implementation, real-valued signals show higher efficiency than complex signals. In this paper, we pre-sent a real-valued delayless subband APA and study both its computational complexity and performance on AEC problems. Compared to the complex valued approach, our method achieves a better performance with lower computational cost. I