Abstract: The present invention increases the flexibility of the modified fast convolution algorithm. In a first exemplary embodiment of the present invention, a block compensator is inserted into the channelizer/de-channelizer processing chain for multiplying data in the processing chain with compensation constants. The block compensator corrects the phase continuity problem associated with the modified fast convolution algorithm to thereby allow unrestricted filter placement. In a second exemplary embodiment, the phase continuity problem is corrected by combining a frequency translation in the frequency domain with a compensatory frequency translation in the time domain. Both techniques increase the flexibility of the modified fast convolution algorithm whilst only marginally increasing computational requirements.