Construction of Non-Binary LDPC Codes with Very Large Girth

A non-binary LDPC codes whose parity check matrix has uniform column weight 2 is constructed in this paper. The approach derives a non-binary LDPC codes from a column-weight 2 binary LDPC codes which is designed according to a all one (2, k) matrix, We proposed a search algorithm for constructing a (2, k) LDPC codes with desired girth, and in this paper, we use the search algorithm twice to obtain a code with larger girth. The simulation result shows that the proposed LDPC codes outperform the random codes.