Polar decoding with schedule diversity based on LDPC-like sparse graphs

In this paper, based on the technique of LDPC (low-density parity-check)-like sparse graphs for the Polar codes, we propose a Polar decoding method which provides the schedule diversity. The investigated decoding schedules outperforms Arikan's belief propagation (BP) algorithm performed on the original encoding factor graph. Secondly, based on both the layered BP (LBP) and the modified node-wise residual BP (NW-RBP) schedules, we are able produce several sequential decoding schedules that are executed in serial. It is shown through simulations that when compared to the successive cancellation list (SCL) decoding, the proposed scheme achieves a lower complexity level, while a gap of 0.2 dB still exists in BER performance in the high-SNR region. However, the enhanced BP-based decoding method provides a flexible decoding latency, and is able to generate soft-in/soft-out information, which makes it suitable for the schemes which perform iterative decoding and detection processes.