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A Theoretical Method for Estimating Performance of Reed-Solomon codes concatenated with Orthogonal Space-Time Block codes

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The Journal of China Universities of Posts and Telecommunications 2002年第1期9卷 30-34页

作者： LUOTao HAOJian-Jun 等 TelecommunicationEngineeringSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876P.R.China TelecommunicationEngineeringSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876

Based on the studies of Reed-Solomon codes and orthogonalspace-time block codes over Rayleigh fading channel, a theoreticalmethod for estimating performance of Reed-Solomon codes concatenatedwith orthogonal space- time block codes is presented in this *** an upper bound of the bit error rate is also obtained. It isshown through computer simulations that the signal-to-noise ratioreduces about 15 dB or more after orthogonal space-time block codesare concatenate with Reed-Solomon(15,6)codes over Rayleigh fadingchannel, when the bit error rate is 10^-4.

关键词： channel codes space-time codes concatenated codes diversity technology

Improved Belief Propagation Decoder for LDPC-CRC-Polar codes with Bit-Freezing

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China Communications 2024年第7期21卷 135-148页

作者： Qasim Jan Yin Chao Pan Zhiwen Muhammad Furqan Zakir Ali You Xiaohu National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211100China Department of Computer Science National University of Computer and Emerging Sciences Peshawar Campus 25100Pakistan Department of Software Engineering Capital University of Science and Technology(CUST)Islamabad 44000Pakistan Department of Computer Sciences Bahria University Lahore CampusPakistan

Though belief propagation bit-flip(BPBF)decoding improves the error correction performance of polar codes,it uses the exhaustive flips method to achieve the error correction performance of CA-SCL decoding,thus resulting in high decoding complexity and *** alleviate this issue,we incorporate the LDPC-CRC-Polar coding scheme with BPBF and propose an improved belief propagation decoder for LDPC-CRC-Polar codes with bit-freezing(LDPCCRC-Polar codes BPBFz).The proposed LDPCCRC-Polar codes BPBFz employs the LDPC code to ensure the reliability of the flipping set,i.e.,critical set(CS),and dynamically update *** modified CS is further utilized for the identification of error-prone *** proposed LDPC-CRC-Polar codes BPBFz obtains remarkable error correction performance and is comparable to that of the CA-SCL(L=16)decoder under medium-to-high signal-to-noise ratio(SNR)*** gains up to 1.2dB and 0.9dB at a fixed BLER=10-4compared with BP and BPBF(CS-1),*** addition,the proposed LDPC-CRC-Polar codes BPBFz has lower decoding latency compared with CA-SCL and BPBF,i.e.,it is 15 times faster than CA-SCL(L=16)at high SNR regions.

关键词： belief propagation bit-flipping concatenated codes LDPC-CRC-Polar codes polar codes

Asymptotic bound on binary self-orthogonal codes

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Science China Mathematics 2009年第4期52卷 631-638页

作者： DING Yang Department of Mathematics, Southeast University, Nanjing 210096, China 1. Department of Mathematics Southeast University Nanjing 210096 China

We present two constructions for binary self-orthogonal codes. It turns out that our constructions yield a constructive bound on binary self-orthogonal codes. In particular, when the in-formation rate R = 1/2, by our constructive lower bound, the relative minimum distance δ≈ 0.0595 (for GV bound, δ≈ 0.110). Moreover, we have proved that the binary self-orthogonal codes asymptotically achieve the Gilbert-Varshamov bound.

关键词： algebraic geometry codes concatenated codes Gilbert-Varshamov bound Reed-Muller codes self-dual basis self-orthogonal codes 11T71

Improving the Structure of Multiple Dimension Turbo codes Using Multiple Identical Component Encoders

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Wuhan University Journal of Natural Sciences 2010年第4期15卷 330-334页

作者： WANG Zhenghai1, TIAN Mao1, WANG Yuhao2 1. School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China 2. School of Information Engineering, Nanchang University, Nanchang 330031, Jiangxi, China School of Electronic Information Wuhan University Wuhan Hubei China School of Information Engineering Nanchang University Nanchang Jiangxi China

In this paper,we propose an improved structure for M-dimension ( M ≥ 2)turbo codes using M identical component encoders. The presented structure only applies single recursive convolutional encoder to encode M interleaved versions of infor-mation sequence and single tail sequence to operate termination. For the commonly used two-dimension (M = 2) turbo codes,two cascade soft input soft output (SISO) decoders are detailed to de-code the corresponding codes. With the two cascade SISO decod-ers,this coding structure obviously outperforms traditional turbo codes at high code rates,especially,about 0.3 dB gain can be ob-tained at code rate 0.9 in additive white Gaussian noise channel with quadrature phase shift keying modulation. This makes the proposed coding structure very attractive for future radio commu-nication systems with high throughput requirements.

关键词： turbo codes concatenated codes convolutional codes soft input soft output (SISO)

A Novel Serially concatenated GMSK System for Satellite Communications

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Chinese Journal of Electronics 2021年第2期30卷 390-396页

作者： HUANG Yun LIU Gang YANG Yinan DING Xingwen CHANG Hongyu School of Telecommunications Engineering Xidian University Beijing Research Institute of Telemetry

A novel serially concatenated GMSK system is proposed for satellite communications subject to low SNR, limited power and spectrum resources. First, we design a Nonrecursive continuous-phase encoder(NRCPE)based GMSK based on the Rimoldi’s decomposition. Then,a corresponding pilot-aided quasi-coherent demodulation algorithm is developed, whose basic principle is that a modified BCJR-based detection performs on the received signals with initial and ending trellisstates being determined using the very limited pilot overhead. Finally,we choose proper modulation parameters for the NRCPE based Gaussian minimum shift keying GMSK signaling according to the trade-offs between the power and spectral efficiency. The simulation results show that the LDPC coded GMSK system using the proposed algorithm can achieve excellent performance and can also work well in the presence of the large Doppler shifts and some burst errors.

关键词： Doppler shift Nonrecursive continuous-phase encoder channel estimation satellite communication modified BCJR-based detection performs corresponding pilot-aided quasicoherent demodulation algorithm concatenated codes novel serially concatenated GMSK system parity check codes minimum shift keying NRCPE satellite communications demodulation

A reduced state SISO iterative decoding algorithm for serially concatenated continuous phase modulation

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Science in China(Series F) 2007年第4期50卷 539-550页

作者： SUN JinHua LI JianDong JIN LiJun State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China

In this paper, serially concatenated continuous phase modulation （SCCPM） system is analyzed and a reduced state soft input soft output （SlSO） a posteriori probability algorithm is proposed. Based on the reduced state sequence detection （RSSD）, it has the more general form compared with other reduced state SISO algorithms. The proposed algorithm can greatly reduce the state number, thus leads to the computation complexity reduction. It also minimizes the degradation in Euclidean distance with decision feedback in the reduced state trellis. Analysis and simulation results show that the performance degradation is little with proper reduction scheme.

关键词： concatenated codes continuous phase modulation (CPM) soft input soft output (SISO) Euclidean distance

Improved iterative breadth-first detection algorithms for MIMO wireless systems

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High Technology Letters 2007年第2期13卷 184-188页

作者：郑武 Song Wentao Zhang Haibin Xu Youyun Electronic Engineering Department of Shanghai Jiaotong University Shanghai 200240 P.R.China Research and Innovation Center Alcatel-Shanghai Bell Co.Ltd. Shanghai 201206P.R.China

A reduced-complexity detection algorithm is proposed, which is applied to iterative receivers for multiple-input multiple-output （MIMO） systems. Unlike the exhaustive search over all the possible trans-mitted symbol vectors of the optimum maximum a posteriori probability （MAP） detector, the new algo-rithm evaluates only the symbol vectors that contribute significantly to the soft output of the detector. The algorithm is facilitated by carrying out the breadth-first search on a reconfigurable tree, constructed by computing the symbol reliability of each layer based on zero-forcing criterion and reordering the symbols according to the symbol reliabilities. Simulations are presented and the good performance of the new algo-rithm over a quasi-static Rayleigh channel even for relatively small list sizes are proved.

关键词： concatenated codes MIMO systems BLAST iterative decoder Turbo codes

SPC-APPM coded modulation for deep-space optical communications

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Optoelectronics Letters 2012年第4期8卷 306-309页

作者：郭建中覃观凤曾蕾 School of Electronics Information Wuhan Textile University

A coded modulation scheme for deep-space optical communications is proposed, which is composed of an outer single- parity-check （SPC）-based product code, an interleaver, a bit-accumulator and a pulse-position modulation （PPM）. It is referred as SPC-APPM code, which is decoded with an iterativc demodulator-decoder using standard turbo-decoding techniques. Investigations show that the scheme has the advantages of low encoding and decoding complexities, good performance and flexible code rate for all rates above I/2. Meanwhile, simulation results demonstrate that the SPC-APPM provides the performance similar to the low-density parity-check-APPM （LDPC-APPM）, superior to the LDPC-PPM and product accumulate code-PPM （PA-PPM）, although inferior to serially concatenated PPM （SCPPM）. At the bit error rate （BER） of 105, the performance of SPC-APPM is about 0.7 dB better than LDPC-PPM and 1.2 dB better than PA-PPM.

关键词： concatenated codes Iterative decoding Optical communication

SERIALLY concatenated CONTINUOUS PHASE MODULATION WITH REDUCED ITERATIVE DEMODULATION AND DETECTION

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Journal of Electronics(China) 2007年第1期24卷 16-22页

作者： Sun Jinhua Li Jiandong Jin Lijun State Key Lab. of Integrated Service Networks Xidian University Xi＇an 710071 China

A reduced state Soft Input Soft Output (SISO) a posteriori probability algorithm for Seri-ally concatenated Continuous Phase Modulation (SCCPM) is proposed in this paper. Based on the Reduced State Sequence Detection (RSSD),it has more general form compared with other reduced state SISO algorithms. The proposed algorithm can greatly reduce the state number,thus leads to the computation complexity reduction. It also minimizes the degradation in Euclidean distance with decision feedback in the reduced state trellis. Analysis and simulation results show that the perform-ance degradation is little with proper reduction scheme.

关键词： concatenated codes Continuous Phase Modulation (CPM) Soft Input Soft Output (SISO) Euclidean distance