A Parity Structure for Scalable QC-LDPC Codes With All Nodes of Degree Three

A novel block triple-diagonal (BTD) parity structure with all nodes of degree three is proposed for quasi-cyclic (QC) low-density parity-check (LDPC) codes. The BTD structure without low node degree can effectively improve the error floor performance and, meanwhile, enable low complexity encoding. With this structure, we use a modulo-lifting technology to construct a family of QC-LDPC codes, which supports scalable code lengths with a simple and flexible encoding solution. The simulation results show that our coding schemes for short and moderate lengths achieve better performance in the error floor region.