In
our globalised and digitalised world, fast and error-free communication
is very important. To ensure this, we use error-correcting codes which
should always be more efficient and have a higher error-correcting
capacity. In this thesis, we investigate two types of LDPC codes which
are obtained from Latin squares. The first is based on orthogonal Latin
squares and the second is formed using Steiner 2-designs generated by a
Latin square. For each code there is a bipartite graph in which cycles
can occur. Such cycles can negatively influence the decoding efficiency.
To counteract this, we will see how to locate and analyse these cycles
and how to remove them.