Quasi-Cyclic Spatially Coupled LDPC Code for Broadcasting

Abstract

Flexible and robust transmission schemes are required to support different coded modulation modes, receiver types and channel conditions in future broadcasting systems. However, conventional low-density parity-check (LDPC) coded schemes are usually optimized towards particular scenario, and may face the problem of performance degradation in other different scenarios. In this paper, a type of quasi-cyclic spatially coupled LDPC (QC-SC-LDPC) codes, which have been recently proven to be able to universally achieve capacity over different channels under conventional belief propagation decoding, are proposed as the forward error correcting codes for broadcasting applications. Then a QC-SC-LDPC coded transmission scheme is proposed, which is capable of showing good performance in various scenarios under practical constraints of finite coupling length, smoothing parameter, uncoupled code length and number of decoding iterations. To maintain the universal property under the above constraints, a typical construction method is developed, based on which a QC-SC-LDPC code is constructed as an example. Finally, the performance and robustness of the proposed QC-SC-LDPC coded transmission scheme are demonstrated via simulations under different yet typical coded modulation modes and channel conditions.