Abstract : This thesis consists on a description of an efficient architecture for a decoding algorithm of algebraic-geometric codes (AG codes) based on Hermitian curves. This work embraces two distinct complementing competences: the study of decoding algorithms for AG codes and the development of architectures for hardware implementation of these decoders. The algorithm, object of this work, searches error locator and evaluator functions iteratively that satisfy a key equation criterion. A new architecture is proposed for this decoder. Optimized operators to implement the most frequent calculations in the decoder are still proposed. The description of the architecture of this decoder follows the description of architectures for arithmetical units in finite fields of characteristic 2, necessary to implemente any channel coding / decoding system using block codes.