STFT computation using pruned FFT algorithms

We show that the discrete short-time Fourier transform with temporal decimation (DSTFT-TD) can be evaluated using a variety of pruned FFT structures. A pruning method we refer to as overlap pruning can be used to eliminate computational overlap between consecutive FFT´s for computing slices of the DSTFT-TD. When only a limited frequency range of the DSTFT-TD is of interest, further computational savings can be achieved by combining overlap pruning with classical frequency pruning. We evaluate the complexity of the overlap and frequency pruned FFT´s for the DSTFT-TD in terms of the number of complex multiplications and additions required for the computation of each DSTFT-TD slice.<>