MATLAB: How to model both Reed-Solomon and Convolutional Encoding in the Communications Blockset 4.4 (R2010a)

communications blockset

I am trying to model both Reed-Solomon coding and Convolutional Encoding in the same model. There are demos provided for each of these ("Reed-Solomon Coding with Erasures, Punctures, and Shortening" and "Punctured Convolutional Coding", respectively). When I try to build a model that fuses both of these coding techniques, the results do not match the results that I expect.

Best Answer

One reason for this may be that for the soft decision process, the noise variance setting of the BPSK demodulator block may be difficult to calculate, and could be wrong (this should be the variance of the noise as specified by the AWGN block). For help with this, there is a demo titled "LLR vs. Hard Decision Demodulation" in the Modulation sub-category of demos which illustrates how this parameter can be specified and derived.