Efficient Decoding Schemes of LDPC Codes for the Layered-Division Multiplexing Systems in ATSC 3.0.

A low-complexity decoding scheme of low-density parity-check codes for the layered-division multiplexing (LDM) systems in ATSC 3.0 is proposed. Based on the unique characteristic of the LDM and the special structure of a parity-check matrix (PCM) for the core layer, the proposed scheme applies the sum-product algorithm (SPA) to only a part of the PCM. For this reason, it is referred to as "the partial SPA," compared with the conventional scheme, denoted by "the full SPA." Clearly, it has a significantly lower complexity than the full SPA. Furthermore, we propose hybrid decoders employing both the full SPA and the partial SPA to achieve a better performance, while maintaining their complexity low. Numerical results show that the proposed schemes have a good performance enough to perform successive interference cancellation for the enhanced layer of the LDM systems in ATSC 3.0 as well as they have a low-complexity merit depending on system parameters. Since they only schedule the decoding procedure without modifying the decoder structure, they also have a benefit in the implementation of decoders.