Bounds on the Error Probability of Raptor Codes under Maximum Likelihood Decoding
In this paper upper bounds on the probability of decoding failure under maximum likelihood decoding are derived for different (non-binary) Raptor code constructions. In particular four different constructions are considered; (i) the standard Raptor code construction, (ii) a multi-edge type construction, (iii) a construction where the Raptor code is non-binary but the generator matrix of the LT code has only binary entries, (iv) a combination of (ii) and (iii). The latter construction resembles the RaptorQ construction, which at the time of writing this article represents the state of the art in fountain codes. The bounds are shown to be tight, and provide an important aid for the design of Raptor codes.
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