High performance full diversity LDPC codes construction and performance analysis for H-ARQ channels by Rui GUO, Fang-ning HU, Ji-lin LIU

“…In order to improve the performance of communication system with hybrid automatic repeat request(H-ARQ),a kind of full diversity low density parity check(LDPC)codes on H-ARQ block-fading channels was proposed.First,the outage probability and inherent diversity were analyzed,then a kind of full diversity PDPC codes for H-ARQ channel was designed.The new proposed LDPC codes connected the initial transmission with the repeated transmissions by root-connection to get extern diversity gain.In addition,the relationship between the structure of full diversity LDPC codes and the coding gain was given,and an algorithm to improve coding gain was brought forward by increasing the proportion of full diversity parity bits.Simulation results show that the proposed algorithm can not only achieve full diversity,but also get better performance than constructed LDPC codes at present.…”
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Reconstruction of LDPC code check matrix based on random extraction at high bit error rate by Zhongyong WANG, Zhenghao LI, Kexian GONG, Peng SUN, Qingtao LI

“…In order to improve the performance of the sparse check matrix reconstruction algorithm of LDPC codes at high BER, an open set recognition algorithm of the check matrix with strong fault tolerance under the condition of sufficient and insufficient number of received code words was proposed.Firstly, a new code word space was constructed by randomly extracting part bits of the code words for many times.Gaussian elimination method was used to solve the dual vector and restore the check vector in a lower dimension.Secondly, using the check vector, the proportion of error-free code groups in the received data was continuously increased by using the methods of “eliminating error code words” or“flipping the lowest unreliable bits” for iterative processing.Simulation results show that the proposed algorithm is superior to comparison algorithm under different bit error rates, different code lengths, different code rates and different number of code words.For (648,324) LDPC codes in IEEE 802.11n protocol, when the number of received code words is sufficient, the reconstruction rate of check matrix can reach more than 95% under the condition of bit error rate of 0.003.When the number of received code words is insufficient (the number of code words is 450), the reconstruction rate of check matrix can reach more than 90% under the condition of bit error rate of 0.0015.…”
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LDPC-coded unitary space-time modulation with low-complexity iterative demodulate-decoding scheme by Li-jiao WANG, Lin ZHANG, Ling-ling YANG, Li PENG, Da-wei FU

“…A practical low-density parity-check(LDPC) coded unitary space-time modulation (USTM) noncoherent MIMO communication system over Rayleigh flat fading and additive white Gaussian noise (AWGN) channel was con-structed, where the LDPC code is selected from IEEE 802.16e Standard and USTM is constructed by the unitary matrix based on the sinc-cosinc function, SC-USTM for short. …”
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Low-complexity likelihood probability derivation algorithm for non-binary LDPC-coded modulation system by Guang-hua HE, Bao-ming BAI, Xiao MA, Bing LI

Subjects: “…non-binary LDPC codes…”
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Weighted symbol-flipping decoding for non-binary LDPC codes based on average probability and stopping criterion by Rui GUO, Chun-yu LIU, Mei-jie WANG, Peng PAN, Jian-rong BAO, Chun-sheng GUO

“…In order to improve the decoding performance and reduce the decoding complexity of weighted symbols flipping decoding algorithm for nonbinary low density parity-check(LDPC)code, a weighted symbols flipping decoding for nonbinary LDPC codes based on average probability and stopping criterion was proposed. …”
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OCT-Precoding Combined with LDPC-Coding Scheme for 128 QAM MB-OFDM UWBoF System by Changqing Xiang, Xi Yang, Xiaojun Zhu, Qiong He, Renmin Zhang, Zhiyang Xiang

“…In this paper, we proposed a coding scheme based on orthogonal cyclic transpose (OCT) precoding combined with low-density parity check (LDPC) code to improve the transmission performance of 128-quadrature amplitude modulation multiband orthogonal-frequency-division-multiplexing ultrawide band over fiber (128 QAM MB-OFDM UWBoF) system. …”
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Applied quasi-cyclic LDPC codes from doubly-extended RS code and cyclic MDS code by ZHANG Guo-hua, WANG Xin-mei

Subjects: “…LDPC code…”
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Study on coded distributed fast Hadamard transform based non-binary LDPC code decoding algorithm by Rui LIU, Yong LI

Subjects: “…non-binary LDPC code decoding…”
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Improvement of Channel Coding System in Narrowband Communication System by Yanjun Wang, Jing Yue, Xue Cui

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Efficient storage method for FPGA-based partially parallel QC-LDPC decoder by Rui-jia YUAN, Bao-ming BAI

Subjects: “…LDPC code…”
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Improved multi-bits flipping algorithm for high-speed LDPC decoding by Ke-xiang MA, Ji-cheng SUN, Meng WANG, Yu-ming ZHANG, Hai-lin ZHANG

Subjects: “…LDPC code…”
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Multilevel coding scheme based on low-density parity-check codes in DAMB by WANG Jia-qing, YU Xiao-yan, WU Le-nan

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Performance of Polar code in diversity reception system by Pingheng ZHAI, Binsong SHEN, Jinbo LIANG

“…Diversity reception is one of the most effective ways to resist fading over Rayleigh fading channels,in order to improve the performance of Polar codes over Rayleigh fading channels,a diversity reception system based on Polar code was proposed.The information bit selectionsequences of Polar codes in diversity reception were determined,and the upper bound of BER for Polar codes in diversity reception system was derived.The simulation results show that when quadruple diversity reception is used,the encoding gain is greater than 3 dB and has 0.6 dB performance advantage compared to LDPC code.Experiment results show that,when eightfold diversity is used,the encoding gain is greater than 5 dB and has 1.5 dB performance advantage compared to LDPC code,and diversity reception can significantly improve the performance of the system.…”
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Optimization design and simplified decoding for short frame CCPM by Xiao-jie DAI, Ya-feng ZHAN

“…Considering the demand of burst communications,optimization and simplified decoding for coded GMSK sys-tem in short frame was focused on to give an optimum proposal of C²PPM system.Simplified demodulator,optimized generation polynomial of the convolution code and matched interleavers were discussed.Simulation results show that for coded GMSK system under AWGN,the performance is better than individual convolution code.Especially when BER is 1×10^-5,it performs better than Turbo code and LDPC code with the same frame length,and there is no error floor occur-ring.Finally,complexity analysis shows that the coded GMSK system has lower implementation complexity in compari-son with the commonly used convolution code,Turbo code and LDPC code.…”
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Research progress of error correction coding in optical wireless communication system by Jingyuan LIANG, Mengru LI, Jiafan WANG, Xizheng KE

“…The channel environment of the optical wireless communication is complicated, susceptible to various natural phenomena such as rain, snow, and fog.The channel code is usually used to correct the error caused by the channel noise.Common channel codes are Reed-Solomon (RS) code, Turbo code, low density parity check (LDPC) code, polarization code and other types.The development of the error correction code was combed, the research progress of the error correction code for the optical wireless communication were summarized and the comparative analysis was made, which introduced the progress of Xi'an University of Technology in this field of theory and experimentation.RS code, Turbo code, LDPC code were comparable to the error correction characteristics in rain, snow and fog environments.Finally, the future possible research direction and challenges were pointed out, providing references for the future development and research in the relevant fields.…”
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An LDPC Encoder Architecture With Up to 47.5 Gbps Throughput for DVB-S2/S2X Standards by Decai Liu, Yanfei Luo, Yunfeng Li, Zhijie Wang, Zhengxuan Li, Qianwu Zhang, Junjie Zhang, Yingchun Li

“…Low-Density Parity-Check (LDPC) code is a type of forward error-correction code with excellent performance, and has been widely used in many modern communication standards. …”
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Joint source-channel coding for image transmission based on best wavelet packet by Jun-hong CHEN, Qin-yu ZHANG

“…A novel joint source/channel image coding algorithm was proposed based on the best wavelet packet in a rate-distortion sense.Different from other wavelet packet image coding,the channel and the channel code information were introduced to the source coding,so the proposed algorithm was a joint source-channel coding.The coding of wavelet packet sub-band was bit plane,accorolingly,the bit streams could be good match to UEP.And a WICP-LDPC code was using as a channel code.The simulation results in BSC channel show that,the proposed algorithm is better than the EEP image transmission system.And the proposed algorithm is also better than several other image transmission algorithms,which proposed recently.…”
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Improved LDPC-based short-range frequency-hopping wireless communication system by Wei-dong FANG, Wu-xiong ZHANG, Ming-ming HU, Wei CHEN, Yang YANG

“…In short-range wireless communication system(SWCS)，the complex scenarios make its transmission face the diverse interference，and lower hardware resource leads to its limited anti-interference capability.To achieve the reliable transmission，a frequency-hopping-based SWCS (FH-SWCS)with improved LDPC (I-LDPC) code was constructed.In FH-SWCS，a low-complexity check-sum updating(LCU)algorithm was proposed to reduce the amount of computation.LCU-based multi-threshold bit flipping (LCU-MTBF) algorithm was given to increase the reliability of bit-flipping， improving decoding performance and reduce the complexity of decoding.The simulation results demonstrate that LCU is suitable for multiple hard decisions decoding algorithm，and it can reduce the computational complexity of original decoding algorithm without affecting its performance.When BER is 10⁻⁵，and iterations number is 5，0.15dB performance gain can be achieved，and the number of additions algorithm can be reduced about 40% in LCU-MTBF.In FH-SWCS with I-LDPC，when BER is 10⁻⁴，and SNR is 15dB，the performance gain about 7dB can be achieved to improve the anti-interference of the system effectively.…”
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Low-density parity-check representation of fault-tolerant quantum circuits by Ying Li

“…We outline the procedure for generating LDPC codes from circuits using the Tanner graph notation, alongside proposing graph-theory tools for constructing fault-tolerant quantum circuits from classical LDPC codes. …”
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Noise immunity of QAM-OFDM signal reception using soft-decision demodulation in the presence of narrowband interference by A. A. Paramonov, V. V. Chu

“…As a way of managing this interference, the paper studies the use of a demodulator with soft outputs and subsequent decoding of the convolutional code and low-density paritycheck (LDPC) code used in the system.Methods. The results presented in the article were obtained using statistical radio engineering, mathematical statistics, encoding theory, and computer modeling.Results. …”
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