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An Improved Group Space-Time Block Code Through Constellation Rotation 认领 引用 被引量：1
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作者 ZHANG Hong-wei +7 位作者 ZHANG Hai-bin SONG Wen-tao LUO Han-wen LIU Xing-zhao 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第4期349-353,共5页
A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has lo... A new improved group space-time block code (G-STBC) based on constellation rotation for four transmit antennas was proposed. In comparison with the traditional G-STBC coding scheme, the proposed space-time code has longer code length and adopts proper rotation-based symbols, which can increase the minimum distance of space-time codes and thereby improve code gain and achieve full diversity performance. The simulation results verify that the proposed group space-time code can achieve better bit error performance than both the traditional group space-time code and other quasi-orthogonal space-time codes. Compared with Ma’s full diversity full rate (FDFR) codes, the proposed space-time code also can achieve the same excellent error performance. Furthermore, the design of the new space-time code gives another new and simple method to construct space-time codes with full diversity and high rate in case that it is not easy to design the traditional FDFR space-time codes. 展开更多
关键词 group space-time block code constellation rotation multiple-input multiple-output （MIMO） full diversity full rate
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Low complexity suboptimal decode algorithms for quasi- orthogonal space time block codes 认领 引用
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作者 李正权 吴名 +2 位作者 沈连丰 王志功 贾子彦 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期1-5,共5页
Due to the high complexity of the pairwise decoding algorithm and the poor performance of zero forcing（ ZF） /minimum mean square error（ MMSE） decoding algorithm, two low-complexity suboptimal decoding algorithms, ... Due to the high complexity of the pairwise decoding algorithm and the poor performance of zero forcing（ ZF） /minimum mean square error（ MMSE） decoding algorithm, two low-complexity suboptimal decoding algorithms, called pairwisequasi-ZF and pairwise-quasi-MMSE decoders, are proposed. First,two transmit signals are detected by the quasi-ZF or the quasiMMSE algorithm at the receiver. Then, the two detected signals as the decoding results are substituted into the two pairwise decoding algorithm expressions to detect the other two transmit signals. The bit error rate（ BER） performance of the proposed algorithms is compared with that of the current known decoding algorithms.Also, the number of calculations of ZF, MMSE, quasi-ZF and quasi-MMSE algorithms is compared with each other. Simulation results showthat the BER performance of the proposed algorithms is substantially improved in comparison to the quasi-ZF and quasiMMSE algorithms. The BER performance of the pairwise-quasiZF（ pairwise-quasi-MMSE） decoder is equivalent to the pairwiseZF（ pairwise-MMSE） decoder, while the computational complexity is significantly reduced. 展开更多
关键词 quasi-orthogonal space-time block code（QOSTBC） low-complexity decoding pairwise-quasi-ZF pairwise-quasi-MMSE bit error rate（BER）
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Linear Dispersion Orthogonal Space-Time Block Codes 认领 引用
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作者 高明 葛建华 李靖 《Journal of Beijing Institute of Technology》 EI CAS 2010年第3期357-361,共5页
A new architecture of space-time codes as a combination of orthogonal space-time block codes （OSTBC） and linear dispersion codes （LDC） is proposed in order to improve the bit error rate（BER） performance of OSTBC... A new architecture of space-time codes as a combination of orthogonal space-time block codes （OSTBC） and linear dispersion codes （LDC） is proposed in order to improve the bit error rate（BER） performance of OSTBC.The scheme proposed is named linear dispersion orthogonal space-time block codes （LDOSTBC）.In LDOSTBC scheme,firstly,the data is coded into LDC codewords.Then,the coded LDC substreams are coded into OSTBC codewords again.The decoding algorithm of LDOSTBC combines linear decoding of OSTBC and ML decoding or suboptimum detection algorithms of LDC.Compared with OSTBC scheme when the rate of LDC is MtR,the performance of LDOSTBC scheme can be improved without decreasing the data rate,where Mt is the number of transmit antennas and R is the spectral efficiency of the modulation constellation.If some rate penalty is allowed,when the rate of LDC is less than MtR the performance of LDOSTBC can be improved further. 展开更多
关键词 space-time coding linear dispersion codes （LDC） orthogonal space-time block codes （OSTBC）
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Space-time Block Codes Based on Quasi-Orthogonal Designs 认领 引用
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作者 李正权 胡光锐 单红梅 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期4-7,共4页
A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is exp... A new space-time block codes based on quasi-orthogonal designs are put forward. First the channel model is formulated. Then the connection between orthogonal /quasi-orthogonal designs and space-time block codes is explored. Finally we make simulations for the transmission of 4 bits/s/Hz and 6 bits/s/Hz using eight transmit antennas using the rate 3/4 quasi-orthogonal space-time block code and the rate 1/2 full-diversity orthogonal space-time block code. Simulation results show that full transmission rate is more important for very low signal noise ratio (SNR) and high bit error probability (BEP), while full diversity is more important for very high SNR and low BEP. 展开更多
关键词 space-time block code orthogonal design quasi-orthogonal.
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Optimal and suboptimal structured algorithms of binary linear block codes 认领 引用
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作者 Yijun Luo Jin Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期1010-1014,共5页
The optimal and suboptimal structured algorithms of linear block codes from the geometrical perspective are represented.The minimum distance and weight property lemmas and the theorem are proved for the generator matr... The optimal and suboptimal structured algorithms of linear block codes from the geometrical perspective are represented.The minimum distance and weight property lemmas and the theorem are proved for the generator matrix.Based upon the property of generator matrix,the structured algorithms of linear block codes are demonstrated.Since the complexity of optimal structured algorithm is very high,the binary linear block codes is searched by using the suboptimal structured algorithm.The comparison with Bose-Chaudhuri-Hocquenqhem(BCH)codes shows that the searched linear block codes are equivalent on minimum distance and can be designed for more block lengths.Because the linear block codes are used widely in communication systems and digital applications,the optimal and suboptimal structured algorithms must have great future being widely used in many applications and perspectives. 展开更多
关键词 channel coding linear block codes generator matrix minimum distance
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EXACT ERROR PROBABILITY OF ORTHOGONAL SPACE-TIME BLOCK CODES OVER FLAT FADING CHANNELS 认领 引用
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作者 Xu Feng Yue Dianwu 《Journal of Electronics(China)》 2007年第4期462-469,共8页
Space time block coding is a modulation scheme recently discovered for the transmit an- tenna diversity to combat the effects of wireless fading channels. Using the equivalent Single-Input Single-Output (SISO) model, ... Space time block coding is a modulation scheme recently discovered for the transmit an- tenna diversity to combat the effects of wireless fading channels. Using the equivalent Single-Input Single-Output (SISO) model, this paper presents closed-form expressions for the exact Symbol Error Rate (SER) and Bit Error Rate (BER) of Orthogonal Space-Time Block Codes (OSTBCs) with M-ary Phase-Shift Keying (MPSK) and M-ary Quadrature Amplitude Modulation (MQAM) over flat un- correlated Nakagami-m and Ricean fading channels. 展开更多
关键词 Orthogonal Space-Time Block Code （OSTBC） Nakagami-m fading channel Ricean fading channel
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A New Generalized Complex Orthogonal Space-Time Block Codes 认领 引用
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 2005年第3期241-243,共3页
Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and... Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and/or receiving antennas to create independent fading channels without penalty in bandwidth efficiency. Space-time block coding is an encoding scheme for communication over Rayleigh fading channels using multiple transmitting antennas. Space-time block codes from complex orthogonal designs exist only for two transmitting antennas. This paper generalizes a new complex orthogonal space-time block code for four transmitting antennas, whose decoding complexity is very low. Simulations show that the generalized complex orthogonal space-time block code has low bit error rate, full rate and possibly large diversity. 展开更多
关键词 space diversity space-time block code multiple antennas generalized complex orthogonal designs.
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UNIT-RATE COMPLEX ORTHOGONAL SPACE-TIME BLOCK CODE CONCATENATED WITH TURBO CODING 认领 引用
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作者 Yu Xiangbin Bi Guangguo 《Journal of Electronics(China)》 2006年第3期346-349,共4页
Space-Time Block(STB)code has been an effective transmit diversity technique for combating fading due to its orthogonal design,simple decoding and high diversity gains.In this paper,a unit-rate complex orthogonal STB ... Space-Time Block(STB)code has been an effective transmit diversity technique for combating fading due to its orthogonal design,simple decoding and high diversity gains.In this paper,a unit-rate complex orthogonal STB code for multiple antennas in Time Division Duplex(TDD)mode is proposed.Meanwhile,Turbo Coding(TC)is employed to improve the performance of proposed STB code further by utilizing its good ability to combat the burst error of fading channel.Compared with full-diversity multiple antennas STB codes,the proposed code can implement unit rate and partial diversity;and it has much smaller computational complexity under the same system throughput.Moreover,the application of TC can effectively make up for the performance loss due to partial diversity.Simulation results show that on the condition of same system throughput and concatenation of TC,the proposed code has lower Bit Error Rate(BER)than those full-diversity codes. 展开更多
关键词 Space-Time Block(STB)codes Turbo-Coding(TC) Unit-rate Multiple antennas Transmit diversity
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Blind identification of space–time block codes based on deep learning 认领 引用 被引量：3
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作者 Limin ZHANG Yuyuan ZHANG +1 位作者 Wenjun YAN Ling MA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第1期426-435,共10页
Deep Learning(DL)has important applications to both commercial and military communications,such as software-defined radio,cognitive radio and spectrum surveillance.While DL has been intensively studied for modulation ... Deep Learning(DL)has important applications to both commercial and military communications,such as software-defined radio,cognitive radio and spectrum surveillance.While DL has been intensively studied for modulation recognition,there are very few investigations for blind identification of Space-Time Block Codes(STBCs).This paper proposes a Residual Network(RN)-based model for identifying 6 kinds of STBC signals with a single receiving antenna,including the same length of coding matrix.In our work,we use the frequency-domain correlation function of a single time delay as the training data of DL model.Then,we explore the suitable RN structure for blind identification of STBCs.Finally,we compare the RN model with convolutional neural network and traditional method,and test the performance of RN model.Simulation results show that our RN-based model provides good performance with low sensitivity to decay of the dataset,such as sample length and data size.At the same time,better identification accuracy can be achieved under the condition of different modulation types and channel fading parameters at low Signal to Noise Ratio(SNR). 展开更多
关键词 Blind identification Deep learning Multiple-input multiple-output Residul network Space-time block code
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Distinction of self-synchronous scrambled linear blockcodes based on multi-fractal spectrum 认领 引用 被引量：4
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作者 xinhao li min zhang +1 位作者 shu'nan han quan yuan 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2016年第5期968-978,共11页
This study proposes a novel multi-fractal spectrumbasedapproach to distinguish linear block codes from its selfsynchronousscrambled codes. Given that the linear block codeand self-synchronous scrambled linear block co... This study proposes a novel multi-fractal spectrumbasedapproach to distinguish linear block codes from its selfsynchronousscrambled codes. Given that the linear block codeand self-synchronous scrambled linear block code share the propertyof linear correlation, the existing linear correlation-basedidentification method is invalid for this case. This drawback can becircumvented by introducing a novel multi-fractal spectrum-basedmethod. Simulation results show that the new method has highrobustness and under the same conditions of bit error, the lowerthe code rate, the higher the recognition rate. Thus, the methodhas significant potential for future application in engineering. 展开更多
关键词 linear block code self-synchronous scrambled code,multi-fractal spectrum statistical physics algorithm.
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A Method for Improving Power Distribution Characteristics of Space Time Block Codes 认领 引用 被引量：3
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作者 Vahid Abbasi Mahrokh G.Shayesteh 《China Communications》 SCIE CSCD 2020年第6期223-234,共12页
Improving power distribution characteristics of space time block codes(STBCs),namely peak to average power ratio(PAPR),average to minimum power ratio(Ave/min),and probability of transmitting“zero”by antenna,makes ea... Improving power distribution characteristics of space time block codes(STBCs),namely peak to average power ratio(PAPR),average to minimum power ratio(Ave/min),and probability of transmitting“zero”by antenna,makes easier their practical implementation.To this end,this study proposes to multiply full diversity STBC with a non-singular matrix in multiple input multiple output(MIMO)or multiple input single output(MISO)systems with linear or maximum likelihood(ML)receivers.It is proved that the obtained code achieves full diversity and the order of detection complexity does not change.The proposed method is applied to different types of STBCs.The bit error rate(BER)and power distribution characteristics of the new codes demonstrate the superiority of the introduced method.Further,lower and upper bounds on the BER of the obtained STBCs are derived for all receivers.The proposed method provides trade-off among PAPR,spectral efficiency,energy efficiency,and BER. 展开更多
关键词 full diversity linear receiver maximum likelihood peak to average power ratio power distribution space time block codes
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Switching Between Antenna Subset Selection and Quasi-Orthogonal Space-Time Block Code in Presence of Correlation 认领 引用
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作者 闫正航 杨宇航 +1 位作者 马懋德 陆亿泷 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第6期651-658,共8页
We address the problem of adaptive modulation and coding scheme(AMCS) for a multi-input multioutput(MIMO) system in presence of time-varying transmitting correlation.Antenna subset selection and quasiorthogonal space-... We address the problem of adaptive modulation and coding scheme(AMCS) for a multi-input multioutput(MIMO) system in presence of time-varying transmitting correlation.Antenna subset selection and quasiorthogonal space-time block code(QOSTBC) have different error performances with different signal-to-noise ratios(SNRs) and in different spatial correlation scenarios.The error performance can be improved by selecting an appropriate transmission scheme to adapt to various channel conditions.The maximum distance criterion is the simplest and very effective algorithm for the antenna subset selection without needs of complex calculation and channel state information at transmitter(CSIT).The minimum error performance criteria and the simplified linear decision strategy are developed for constant transmission rate traffic to select the optimal transmission scheme.It can dramatically decrease algorithm complexity for obtaining error probability according to the known quantities comparing with using instant CSIT.Simulation results show that,remarkable performances including low SNR and weak spatial correlation at the expense of simple calculation and almost no bandwidth loss by adopting AMCS can be achieved.The proposed AMCS improves robustness of slowly varying spatial correlated channels. 展开更多
关键词 multi-input multi-output （MIMO） adaptive modulation and coding quasi-orthogonal space-time block code （QOSTBC） correlated fading channels antenna subset selection
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Joint channel estimation and symbol detection for space-time block code 认领 引用
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作者 单淑伟 罗汉文 宋文涛 《Journal of Systems Engineering and Electronics》 2004年第3期266-269,共4页
The simplified joint channel estimation and symbol detection based on the EM (expectation-maximization) algorithm for space-time block code (STBC) are proposed. By assuming channel to be invariant within only one STBC... The simplified joint channel estimation and symbol detection based on the EM (expectation-maximization) algorithm for space-time block code (STBC) are proposed. By assuming channel to be invariant within only one STBC word and utilizing the orthogonal structure of STBC, the computational complexity and cost of this algorithm are both very low, so it is very suitable to implementation in real systems. 展开更多
关键词 space-time block code expectation-maximization algorithm channel estimation symbol detection.
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Performance of MIMO Systems Using Space Time Block Codes (STBC) 认领 引用 被引量：1
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作者 Christopher M. Lau 《Open Journal of Applied Sciences》 2021年第3期273-286,共14页
Digital Communications, in relation to wireless networks, have taken off in recent years due to the expanding need to communicate faster and more efficiently. A popular way to achieve this is by using wireless Multipl... Digital Communications, in relation to wireless networks, have taken off in recent years due to the expanding need to communicate faster and more efficiently. A popular way to achieve this is by using wireless Multiple Input Multiple Output (MIMO) communication systems. MIMO systems utilize Space Time Block Codes (STBC) as one of the leading ways to obtain higher data rates with limited bandwidth and power. With several STBC methods currently available, this paper analyzes simulations using Orthogonal Space Time Block Codes (OSTBC) in Rayleigh fading channels to evaluate the performance of MIMO systems. The selection to use a Rayleigh fading channel as a model for a non-line-of-sight (nLOS) environment is selected to mimic installations where a large number of signal paths and reflections are expected. All simulations are coded, generated and plotted using MATLAB resulting in graphical data representing the bit-error rate (BER) to signal-to-noise ratio (Eb/N0) or SNR. Each simulation captures how different configurations of key variables including code rate, diversity and antenna count can impact system performance. Four modulation schemes (BPSK, QPSK, 16-QAM and 64-QAM) are included in each simulation. Conclusive evidence based upon these simulations suggests higher diversity gains were achieved with a greater number of antennas. The most significant factor for increasing system performance was using a lower count of transmit antennas with a higher count of receive antennas. 展开更多
关键词 Computer Analysis Digital Communications MATLAB MIMO Modulation Techniques Multiple Input Multiple Output Systems Orthogonal Space Time Block Codes OSTBC Rayleigh Fading Channels Space Time Block Codes STBC Wireless Communications Wireless Networks
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FREQUENCY-TIME BLOCK CODE FOR FREQUENCY DIVERSITY IN UWB-OFDM SYSTEMS 认领 引用
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作者 Xu Bin Yang Chenyang Bi Guangguo 《Journal of Electronics(China)》 2006年第4期481-484,共4页
The Ultra-WideBand Orthogonal Frequency Division Multiplexing (UWB-OFDM) approach is a promising physical-layer technique for short-range, high data-rate wireless networks. As the occupied band-width increases, howeve... The Ultra-WideBand Orthogonal Frequency Division Multiplexing (UWB-OFDM) approach is a promising physical-layer technique for short-range, high data-rate wireless networks. As the occupied band-width increases, however, its implementation becomes more and more difficult. In order to make it easier to achieve a UWB-OFDM system, a complexity-reduced Frequency diversity (F-diversity) scheme, Fre-quency-Time Block Code (FTBC), is presented in this paper. The FTBC halves the sampling rate required by other F-diversity techniques so as to cut down the cost of UWB-OFDM systems with F-diversity to a certain extent. 展开更多
关键词 Ultra-WideBand （UWB） Orthogonal Frequency Division Multiplexing （OFDM） Frequency diversity Frequency-Tilne Block Code （FTBC） Wireless Personal Area Networks （WPAN）
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Single-channel blind source separation empowered joint transceiver optimization for wireless communications using deep learning 认领 引用
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作者 Pengcheng Guo Fuqiang Yao +3 位作者 Miao Yu Cheng Li Yanqun Tang Zhaolong Ning 《Digital Communications and Networks》 SCIE EI CSCD 2026年第1期76-85,共10页
To tackle the physical layer security challenges in wireless communication,this paper introduces a multiuser architecture that leverages single-channel blind source separation,centered around a Multi-source Signal Mix... To tackle the physical layer security challenges in wireless communication,this paper introduces a multiuser architecture that leverages single-channel blind source separation,centered around a Multi-source Signal Mixture Separator(MSMS).This architecture consists of a multi-user encoder,a channel layer,and a separation decoder,allowing it to handle multiple functions simultaneously,including encoding,modulation,signal separation,demodulation,and decoding.The MSMS receiver effectively enables the separation of numerous user signals,making it exceedingly difficult for unauthorized eavesdroppers to extract valuable information from the mixed signals,thus significantly enhancing communication security.The MSMS can address the challenges of few-shot sample training and achieve joint optimization during transmission by employing a deep learning-based network design.The design of a single receiver reduces system costs and improves spectrum efficiency.The MSMS outperforms traditional Space-time Block Coding(STBC)strategies regarding separation performance,particularly in Block Error Rate(BLER)metrics.Modulation constellation diagrams further analyze the effectiveness of multi-source signal mixture separation.Moreover,this study extends the MSMS framework from a two-user scenario to a three-user scenario,further demonstrating the flexibility and scalability of the proposed architecture. 展开更多
关键词 Physical layer security Multi-user wireless communication Single-channel source separation Deep learning Space-time block coding
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New code match strategy for wideband code division multiple access code tree management 认领 引用 被引量：1
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作者 杨宗凯 刘光然 何建华 《Journal of Central South University of Technology》 2006年第3期265-269,共5页
Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new... Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new code match scheme for WCDMA code tree management was proposed. The code match scheme is similar to the existing crowed-first scheme. When choosing a code for a user, the code match scheme only compares the one up layer of the allocated codes, unlike the crowed-first scheme which perhaps compares all up layers. So the operation of code match scheme is simple, and the average time delay is decreased by 5.1%. The simulation results also show that the code match strategy can decrease the average code blocking probability by 8.4%. 展开更多
关键词 orthogonal variable spreading factor code placement strategy code match strategy code blocking probability
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帧级纹理复用的AVS3划分和帧内预测算法 认领 引用
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作者 张全 王顺 +2 位作者 刘洋毅 段昶 彭博 《电讯技术》 北大核心 2026年第7期1211-1220,共10页
为提升音视频编解码第三代标准(Third-generation Audio Video Coding Standard,AVS3)的编码效率,提出了一种使用帧级纹理信息的编码单元(Coding Unit,CU)划分和帧内预测联合快速算法,计算过程中,每帧纹理信息只计算一次,将其复用于编... 为提升音视频编解码第三代标准(Third-generation Audio Video Coding Standard,AVS3)的编码效率,提出了一种使用帧级纹理信息的编码单元(Coding Unit,CU)划分和帧内预测联合快速算法,计算过程中,每帧纹理信息只计算一次,将其复用于编码的两个阶段,从而提高编码效率。首先,以帧为单位在图形处理器(Graphics Processing Unit,GPU)端计算图像的纹理信息,过程中利用积分图降低其计算复杂度;其次,根据CU的纹理信息及二叉树划分的编码代价,指导后续CU划分;最后,通过分层的帧内预测模式搜索,结合纹理信息,逐层确定最优预测模式。实验结果显示,与AVS3官方参考软件HPM15.0相比,在BD-Rate增加0.46%的情况下,所提算法平均减少了36%的编码时间,有效降低了AVS3的计算复杂度。 展开更多
关键词 视频编解码 编码单元划分 帧内预测 边缘检测
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基于块差分编码的正交频分复用水声通信系统 认领 引用 被引量：4
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作者 张译元 武岩波 朱敏 《声学学报》 EI CAS CSCD 北大核心 2026年第2期649-661,共13页
在正交频分复用(OFDM)系统中,块差分编码方案中的差分调制能够在信道状态未知的情况下实现低复杂度鲁棒通信,其编码过程带来的分集增益可有效提升抗衰落性能。然而,水声信道的强时频双选性与低信噪比仍是限制当前系统应用的主要问题。... 在正交频分复用(OFDM)系统中,块差分编码方案中的差分调制能够在信道状态未知的情况下实现低复杂度鲁棒通信,其编码过程带来的分集增益可有效提升抗衰落性能。然而,水声信道的强时频双选性与低信噪比仍是限制当前系统应用的主要问题。本文提出一种基于块差分编码的OFDM水声通信系统,在发射端使用频域块差分编码方案,并与多进制Turbo码级联,以提高低信噪比条件下的可靠性;针对信道双选性造成相邻子载波相关系数下降的问题,提出一种基于子载波相关系数估计值的多进制差分符号对数似然矢量计算方法。仿真结果表明,在时变多径水声信道下,所提方案在频带利用率为0.5(bit/s)/Hz和1(bit/s)/Hz时相比同速率的差分相移键控和相移键控方案存在4 dB和2 dB增益。海试结果表明,所提方案在频带利用率为0.5(bit/s)/Hz和1(bit/s)/Hz时,正确译码的信噪比门限分别为7 dB和11 dB。 展开更多
关键词 块差分编码 符号级Turbo码 正交频分复用 频率分集
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面向移动通信的概率成形两层编码调制方案 认领 引用
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作者 袁瑞敏 刘凌 白宝明 《电子学报》 EI CAS CSCD 北大核心 2026年第3期1296-1309,共14页
作为一种新型的编码调制方案,概率成形的两层编码调制(Two-Level Coded Modulation with Probabilistic Shaping,TLCM-PS)提供了编码增益和成形增益,同时保持了适中的复杂度。然而,现有的TLCM-PS方案尚未针对移动通信中的信道衰落问题... 作为一种新型的编码调制方案,概率成形的两层编码调制(Two-Level Coded Modulation with Probabilistic Shaping,TLCM-PS)提供了编码增益和成形增益,同时保持了适中的复杂度。然而,现有的TLCM-PS方案尚未针对移动通信中的信道衰落问题提出有效的解决方案。为此,本文提出了一种适用于衰落信道的TLCM-PS方案。具体而言,对于高阶信号星座的低可靠度标号比特,采用5G低密度校验码(Low-Density Parity-Check,LDPC)码进行保护;对于高可靠度标号比特,则使用基于硬判决译码的Bose-Chaudhuri-Hocquenghem(BCH)码进行保护。在衰落信道下,利用空时分组编码和多天线技术获取分集增益,减少了低可靠度标号的解调错误概率,从而使BCH码输出很低的错误概率。高可靠度标号比特采用了并行解映射,低可靠度标号比特采用硬判决解映射。基于这一特点,本文分析了编码调制系统的可达速率。基于可达速率分析,以及分集增益对低可靠度标号比特错误率的影响,本文提出了一种针对星座成形、LDPC编码和BCH编码的冗余分配方法。首先在无BCH码的假设下,通过优化可达速率确定成形和LDPC码的最优冗余分配,得到一个好的瀑布区性能。然后固定LDPC码的冗余,取出小部分成形冗余给BCH码,以轻微的瀑布区性能回退换取子集内标号比特的可靠度。仿真结果表明,所提方案在2×2天线的瑞利衰落信道下能保持低于10-4的误帧率,并且相较于均匀的比特交织编码调制系统,所提方案在高于6.0比特/二维的传输速率下具有0.75 dB的增益。此外,分析表明,相较于均匀的比特交织编码调制系统,所提方案的复杂度显著降低。 展开更多
关键词 两层编码调制 星座成形 多输入多输出 信道衰落 空时分组码 LDPC码
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