High‐throughput 2 bit low‐density parity‐check forward error correction for C‐RAN optical fronthaul based on a hard‐decision algorithm

Abstract

In this study, the authors demonstrate the potentiality of the integration of low-density parity-check codes with a full self-seeded optical architecture using advanced optical and electrical models. This study aims to show the performances that one can expect from this association in the context of cloud radio access network (C-RAN). Different decoding algorithms have been studied over additive white Gaussian noise channel. Hard-decision algorithm of Gradient descent bit flipping (GDBF) is finally chosen since it represents the best trade-off between the complexity of decoder and the performance. Furthermore, the authors show that a small 2-bit quantification is sufficient, which can increase the data rate and decrease the latency of decoder in comparison with a more complex ADs. The same performance of floating point GDBF is achieved by using the new algorithm Balanced Weighted GDBF (BWGDBF) with 2-bit quantification. Finally, the authors have succeeded to implement BWGDBF algorithm on the FPGA Spartan 6 xc6slx16. The proposed system exhibits very good performances since it is able to achieve 2.5 Gb/s throughput in the C-RAN context.