Article details

Title: Blind Recovery of the Second Convolutional Encoder of a Turbo-Code when Its Systematic Outputs Are Punctured
Author(s): Mélanie Marazin   Roland Gautier   Gilles Burel         

Abstract: Turbo-codes are error-correcting codes used in powerful digital transmission systems to ensure a low binary error rate. This paper presents different approaches aimed at recovering a convolutional encoder in a non-cooperative context like in military interception or cognitive-radio applications. In this context, the intercepted data are the only known information. It also explains the residual indetermination due to “equivalent” coders and it gives the link between an NRNSC encoder and its RSC equivalent form. Furthermore, it reports on a new approach developed to recover the interleaved version of the second encoder of a Turbo-code when its systematic outputs are punctured.

Keywords: Cognitive-Radio Applications, Turbo-Code, Convolutional Encoder, Interleaver, Blind Estimation, Non-Cooperative Communications, Interception.

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