International Conference on Wireless Communications and Signal Processing (WCSP)

Tabu-List Noisy Gradient Descent Bit Flipping Decoding of LDPC Codes

Li Guo Zhang, Nan Liu, Zhiwen Pan, Xiaohu You

Published Oct 1, 2019• 2 citations

Abstract

The Noisy Gradient Descent Bit Flipping (NGDBF) algorithm surpasses the previous Gradient Descent Bit Flipping (GDBF) and other Bit Flipping (BF) algorithms for decoding Low-Density Parity-Check (LDPC) codes. However, the NGDBF decoder sometimes cannot escape from the local maxima. To further enhance the performance of the NGDBF algorithm, an improved NGDBF algorithm called Tabu-List Noisy Gradient Descent Bit Flipping (TNGDBF) is proposed in this paper. A tabu-list is employed to help the NGDBF decoder escape from the local maxima. It is shown in the simulation results that the TNGDBF algorithm gains about 0.2 dB performance compared with NGDBF at the cost of a small amount of complexity increase.

DOI: 10.1109/wcsp.2019.8927932

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