Efficient realization of the block frequency domain adaptive filter

In many frequency domain adaptive filters fast Fourier transforms (FFTs) are used to transform signals which are augmented with zeros. The overall computational complexity of these adaptive filters is mainly determined by these windowed FFTs, rather than by the filtering operation itself. This article presents a new way of calculating these windowed FFTs efficiently. In addition, a method is deduced for implementing non-windowed FFTs of overlapping input data using the previously mentioned efficient windowed FFTs. Also, a method is presented for implementing the windowed FFTs in the update part even more efficient