Critically subsampled filterbanks implementing Reed-Solomon codes

The last decade shows a growing interest in soft decoding techniques. These techniques are almost never applied to existing nearly perfect codes, but instead other families of concatenated codes arise with Turbo codes as the main example. The problem is that for the application of soft decoding, the perfect codes need to be broken into several smaller component codes. In this paper, the family of Reed-Solomon Codes is considered and using filterbanks, they are broken into several component codes (one in each subband). This paper focuses on the construction of such filterbanks, and gradually evolves towards a critically subsampled filterbank. The critical subsampling is crucial if the filterbank is going to be used in a soft decoding setup.