TY - JOUR AU - C. da Rocha Jr., Valdemar AU - G. Farrell, Patrick PY - 2015/06/16 Y2 - 2024/03/28 TI - Algebraic Soft-Decision Techniques for Linear Block CodesDOI: 10.14209/jcis.1990.4 JF - Journal of Communication and Information Systems JA - Journal of Communication and Information Systems VL - 5 IS - 1 SE - Regular Papers DO - UR - https://jcis.sbrt.org.br/jcis/article/view/158 SP - AB - <span>This paper presents a way of incorporating soft-decision information as an integral part of the process of decoding linear block codes which have an algebraic structure. The quantised demodulator output levels of a soft-decision communication system are represented by the elements of a Galois field. As a consequence it is then possible to define a soft syndrome, a soft standard array and a soft trellis for decoding linear block codes. This approach stands in opposition to deconding methods which combine hard-decisions with the digit reliability measures in an ad-hoc fashion. A soft version of an error-trapping decoder for cyclic codes is given as an application of the theory developed. The basic BCH (Bose-Chaudhuri-Hocquenghem) algebraic algorithm needs to be modified in order to benefit from the procedures here described.</span> ER -