This paper introduces a linear permutation module before the inner encoder of the iteratively decoded product coding structure, for the transmission of scalable bitstreams over error-prone channels(1). This can improv...
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ISBN:
(纸本)9781509037247
This paper introduces a linear permutation module before the inner encoder of the iteratively decoded product coding structure, for the transmission of scalable bitstreams over error-prone channels(1). This can improve the error correction ability of the inner code when some source bits are known from the preceding outer code decoding stages. The product code consists of a protograph low-density parity-check code (inner code) and Reed-Solomon (RS) codes of various strengths (outer code). Further, an algorithm relying on protograph-based extrinsic information transfer analysis is devised to design good base matrices from which the linear permutations are constructed. In addition, an analytical formula for the expected fidelity of the reconstructed sequence is derived and utilized in the optimization of the RS codes redundancy assignment. The experimental results reveal that the proposed approach consistently outperforms the scheme without the linear permutation module, reaching peak improvements of 1:98 dB and 1:30 dB over binary symmetric channels (BSC) and additive white Gaussian noise (AWGN) channels, respectively.
The multi-level-cell (MLC) NAND flash memory exhibits a diversity of the raw bit error rate (BER) over different program/erase (P/E) cycles and different types of bits within a memory cell. In this letter, we first ap...
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The multi-level-cell (MLC) NAND flash memory exhibits a diversity of the raw bit error rate (BER) over different program/erase (P/E) cycles and different types of bits within a memory cell. In this letter, we first apply a protograph-based extrinsic information transfer chart analysis to the MLC flash channel and design novel rate-adaptive protograph low-density parity-check (RAP-LDPC) codes by using a code extension approach. The proposed RAP-LDPC code has multiple code rates, which can be adapted dynamically to different P/E cycles. To mitigate the unbalanced raw BERs between different types of bits within a memory cell, we further propose an optimum mapping between the variable nodes of the protograph and different types of bits of the memory cell. Since the proposed RAP-LDPC codes are based on the same parity-check matrix with specific structure, a single protograph encoder/decoder is sufficient to handle all the code rates. Simulation results demonstrate that the proposed RAP-LDPC codes with optimum mapping outperform the irregular LDPC codes for all the code rates with a faster decoding convergence speed for the MLC flash channel.
For two-way relay channel-coded physical network coding (CPNC) systems with sufficiently low code rate, the separate complete decoding (SCD) scheme outperforms the joint channel-physical network coding (JCNC) scheme. ...
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ISBN:
(纸本)9781509032549
For two-way relay channel-coded physical network coding (CPNC) systems with sufficiently low code rate, the separate complete decoding (SCD) scheme outperforms the joint channel-physical network coding (JCNC) scheme. Hence, this paper addresses the design of protograph LDPC codes to approach the SCD-based CPNC capacity. In fact, due to virtual erasures induced by CPNC transmission, the conventional protograph that approaches point to point (P2P) AWGN capacity may not perform well in SCD-based CPNC channel in terms of error rates. We then use the finite-length EXIT chart to calculate iterative decoding threshold of a joint code graph formed by two codes in the SCD. Furthermore, we investigate the serial separate complete decoding (S-SCD) and parallel separate decoding (PSCD). Simulation results show that with the S-SCD, the proposed protograph codes have within 0.9 dB of their capacity limits for rates from 1/3 to 3/5.
Bit-interleaved coded modulation (BICM) has attracted considerable attention from the research community in the past three decades, because it can achieve desirable error performance with relatively low implementation...
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Bit-interleaved coded modulation (BICM) has attracted considerable attention from the research community in the past three decades, because it can achieve desirable error performance with relatively low implementation complexity for a large number of communication and storage systems. By exploiting the iterative demapping and decoding (ID), the BICM is able to approach capacity limits of coded modulation over various channels. In recent years, protograph low-density parity-check (PLDPC) codes and their spatially-coupled (SC) variants have emerged to be a pragmatic forward -error-correction (FEC) solution for BICM systems due to their tremendous error-correction capability and simple structures, and found widespread applications such as deep-space communication, satellite communication, wireless communication, optical communication, and data storage. This article offers a comprehensive survey on the state-of-the-art development of PLDPC-BICM and its innovative SC variants over a variety of channel models, e.g., additive white Gaussian noise (AWGN) channels, fading channels, Poisson pulse position modulation (PPM) channels, and flash-memory channels. Of particular interest is code construction, constellation shaping, as well as bit-mapper design, where the receiver is formulated as a serially-concatenated decoding framework consisting of a soft-decision demapper and a belief-propagation decoder. Finally, several promising research directions are discussed, which have not been adequately addressed in the current literature.(c) 2022 Published by Elsevier B.V.
For two-way relay channel-coded physical network coding (CPNC) systems with sufficiently low code rate, the separate complete decoding (SCD) scheme outperforms the joint channel-physical network coding (JCNC) scheme. ...
详细信息
ISBN:
(纸本)9781509032556
For two-way relay channel-coded physical network coding (CPNC) systems with sufficiently low code rate, the separate complete decoding (SCD) scheme outperforms the joint channel-physical network coding (JCNC) scheme. Hence, this paper addresses the design of protograph LDPC codes to approach the SCD-based CPNC capacity. In fact, due to virtual erasures induced by CPNC transmission, the conventional protograph that approaches point to point (P2P) AWGN capacity may not perform well in SCD-based CPNC channel in terms of error rates. We then use the finite-length EXIT chart to calculate iterative decoding threshold of a joint code graph formed by two codes in the SCD. Furthermore, we investigate the serial separate complete decoding (S-SCD) and parallel separate decoding (PSCD). Simulation results show that with the S-SCD, the proposed protograph codes have within 0.9 dB of their capacity limits for rates from 1/3 to 3/5.
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