Selective-Update Decoding of Non-Binary LDPC Codes

Non-binary LDPC codes are promising error correcting techniques with very good performance, especially for high order fields. Using higher order fields enhances performance but, at the same time, increases decoding complexity. Several methods have been proposed to reduce this complexity, such as sub-optimal decoding algorithms or techniques aiming at reducing the number of iterations. In this paper, a technique for selective check nodes update is presented enabling a complexity reduction at the level of iteration in the non-binary case. More than 35% of complex updates can be saved in a large SNR region, with parameters that can be tuned according to the desired complexity/performance ratio.