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NEW ITERATIVE SUPER-TRELLIS DECODING WITH SOURCE A PRIORI INFORMATION FOR VLCS WITH TURBO CODES 被引量:3
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作者 Liu Jianjun Tu Guofang Wu Weiren 《Journal of Electronics(China)》 2007年第1期122-127,共6页
A novel Joint Source and Channel Decoding (JSCD) scheme for Variable Length Codes (VLCs) concatenated with turbo codes utilizing a new super-trellis decoding algorithm is presented in this letter. The basic idea of ou... A novel Joint Source and Channel Decoding (JSCD) scheme for Variable Length Codes (VLCs) concatenated with turbo codes utilizing a new super-trellis decoding algorithm is presented in this letter. The basic idea of our decoding algorithm is that source a priori information with the form of bit transition probabilities corresponding to the VLC tree can be derived directly from sub-state transitions in new composite-state represented super-trellis. A Maximum Likelihood (ML) decoding algorithm for VLC sequence estimations based on the proposed super-trellis is also described. Simu-lation results show that the new iterative decoding scheme can obtain obvious encoding gain especially for Reversible Variable Length Codes (RVLCs),when compared with the classical separated turbo decoding and the previous joint decoding not considering source statistical characteristics. 展开更多
关键词 Joint Source and channel Decoding (JSCD) Variable Length codes (VLCs) turbo codes Super-trellis
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Turbo Codes with Modified Code-matched Interleaver over A WGN and Rayleigh Fading Channel 被引量:1
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作者 罗骥 张曦林 袁东风 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第2期147-152,共6页
A novel Code-Matched interleaver is proposed which decreases the number of the low weight codewords to improve the performance of the Turbo code. The modified design can adapt more kinds of Turbo codes determined by t... A novel Code-Matched interleaver is proposed which decreases the number of the low weight codewords to improve the performance of the Turbo code. The modified design can adapt more kinds of Turbo codes determined by the generator matrix, while it doesn't decrease the bit error rate performance of Turbo codes at moderate to high signal to noise ratio. At the same time, in Rayleigh fading channel, the new Code-Matched interleaver can also debase the error floor. 展开更多
关键词 turbo INTERLEAVER weight distribution Code-Matched distance spectrum
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APPLICATION OF TURBO CODES IN HIGH-SPEED REAL-TIME CHANNEL
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作者 Zhao Danfeng Yue Li Yang Jianhua 《Journal of Electronics(China)》 2006年第4期602-605,共4页
The time delay of Turbo codes due to its iterative decoding is the main bottleneck of its application in real-time channel. However, the time delay can be greatly shortened through the adoption of parallel decod-ing a... The time delay of Turbo codes due to its iterative decoding is the main bottleneck of its application in real-time channel. However, the time delay can be greatly shortened through the adoption of parallel decod-ing algorithm, dividing the received bits into several sub-blocks and processing in parallel. This letter mainly discusses the applicability of turbo codes in high-speed real-time channel through the study of a parallel turbo decoding algorithm based on 3GPP-proposed turbo encoder and interleaver in various channel. Simulation re-sult shows that, by choosing an appropriate sub-block length, the time delay can be obviously shortened with-out degrading the performance and increasing hardware complexity, and furthermore indicates the applicability of Turbo codes in high-speed real-time channel. 展开更多
关键词 turbo codes Block parallel decoding Real-time channel
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基于SPIHT图象压缩编码的Turbo codes编码 被引量:7
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作者 徐雯 郭立 刘昌进 《中国科学技术大学学报》 CAS CSCD 北大核心 2002年第2期202-209,共8页
针对信源与信道编码的特点 ,提出了结合SPIHT(setpartitioninginhierarchicaltrees)算法和改进的TurboCodes的信源与信道联合编码方案 .这一方案充分考虑了SPIHT算法和TurboCodes的特性 ,根据信源编码后数据在重建时的重要程度 ,进行不... 针对信源与信道编码的特点 ,提出了结合SPIHT(setpartitioninginhierarchicaltrees)算法和改进的TurboCodes的信源与信道联合编码方案 .这一方案充分考虑了SPIHT算法和TurboCodes的特性 ,根据信源编码后数据在重建时的重要程度 ,进行不同等纠错保护的信道编码 .实验表明 ,论文的方法能够使误码率与码长达到一个较好的平衡 。 展开更多
关键词 SPIHT 图象压缩编码 turbo codes编码 turbo 联合编码 不同等差错保护 信源编码 信道编码 纠错编码
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Turbo Codes的抗远近效应性能分析 被引量:1
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作者 吴灏 何翔 +1 位作者 宋文涛 罗汉文 《电讯技术》 北大核心 1998年第6期28-30,58,共4页
一种崭新的信道编码技术TurboCodes(TC)以其优越的纠错性能很快在通信领域得到实际应用。本文讨论了这一技术在CDMA系统中的应用。由于采用了这种前向差错控制(FEC)信道编码技术,使得CDMA系统具有了较好的... 一种崭新的信道编码技术TurboCodes(TC)以其优越的纠错性能很快在通信领域得到实际应用。本文讨论了这一技术在CDMA系统中的应用。由于采用了这种前向差错控制(FEC)信道编码技术,使得CDMA系统具有了较好的抗远近效应性能。 展开更多
关键词 turbo codes FEC信道编码 远近效应 CDMA
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Turbo-TCM Performance under AWGN and Rayleigh Fading Channels 被引量:2
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作者 任俊涛 王睦重 邵定蓉 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第2期86-90,共5页
A simple algorithm for Turbo TCM decoding was given in this paper. With this algorithm, Turbo TCM can easily be used to real systems with various code rates and modulations of QPSK, 8PSK, 16QAM or 64QAM. The bit err... A simple algorithm for Turbo TCM decoding was given in this paper. With this algorithm, Turbo TCM can easily be used to real systems with various code rates and modulations of QPSK, 8PSK, 16QAM or 64QAM. The bit error ratio performance was studied under AWGN and fading channels. The simulation results were also given in this paper. 展开更多
关键词 turbo codes TCM AWGN channel Rayleigh fading channel
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Interleaver Design Method for Turbo Codes Based on Genetic Algorithm 被引量:2
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作者 TanYing SunHong ZhouHuai-bei 《Wuhan University Journal of Natural Sciences》 CAS 2004年第3期323-326,共4页
This paper describes a new interleaver construction technique for turbo code. The technique searches as much as possible pseudo-random interleaving patterns under a certain condition using genetic algorithms(GAs). The... This paper describes a new interleaver construction technique for turbo code. The technique searches as much as possible pseudo-random interleaving patterns under a certain condition using genetic algorithms(GAs). The new interleavers have the superiority of the S-random interleavers and this interleaver construction technique can reduce the time taken to generate pseudo-random interleaving patterns under a certain condition. The results obtained indicate that the new interleavers yield an equal to or better performance than the S-random interleavers. Compared to the S-random interleaver, this design requires a lower level of computational complexity. Key words interleaver - Turbo codes - genetic algorithm CLC number TN 911. 22 Foundation item: Supported by the National Natural Science Foundation of China (60372057) and the Key Open Laboratory on Information Science and Engineering of Railway Transportation Ministry of Beijing Jiaotong University of China (KLISAE-0103)Biography: Tan Ying (1963-), female, Associate professor, Ph. D, research direction: error control coding, analysis and design of wireless communication system. 展开更多
关键词 INTERLEAVER turbo codes genetic algorithm
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Improving the BER performance of turbo codes with short frame size based on union bound 被引量:1
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作者 邵霞 Li Ping Zhang Weidang 《High Technology Letters》 EI CAS 2015年第3期309-314,共6页
timizing the formula, the energy for every bit of the codeword is optimized to achieve the minimum BER at high SNR region. At last, an adjustable parameter is employed to compensate the degrada- tions of BER at low an... timizing the formula, the energy for every bit of the codeword is optimized to achieve the minimum BER at high SNR region. At last, an adjustable parameter is employed to compensate the degrada- tions of BER at low and moderate SNR regions. Case studies indicate that the improvements of BER for turbo codes with short frame size are significant at a wide range of SNR 展开更多
关键词 channel coding bit error rate (BER) energy allocation turbo code
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Performance Research on Turbo TCM Schemes Using Different Set Partitioning Strategies for Fading Channels
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作者 罗骥 袁东风 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第1期53-58,共6页
Two different set partitioning strategies used in Turbo TCM, UP (Ungerboeck Partitioning) and BP (Block Partitioning) are compared over Rayleigh fading channels. The performance of Turbo TCM with the two set parti... Two different set partitioning strategies used in Turbo TCM, UP (Ungerboeck Partitioning) and BP (Block Partitioning) are compared over Rayleigh fading channels. The performance of Turbo TCM with the two set partitioning strategies and different frame length over Rayleigh fading channels is evaluated. The simulation results of 8PSK and 8ASK modulation and some significant conclusions are also given in this paper. 展开更多
关键词 turbo turbo trellis code modulation set partitioning Rayleigh fading channel
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Channel Coding Techniques for VHF-Mobile Radio System and Its DSP Implementation
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作者 肖国军 黄红凯 +1 位作者 刘家康 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期316-319,共4页
Two variable channel-coding schemes with unequal error protection (UEP) are proposed in terms of speech transmission over VHF-mobile radio system. These channel coding are separately based on rate-compatible punctur... Two variable channel-coding schemes with unequal error protection (UEP) are proposed in terms of speech transmission over VHF-mobile radio system. These channel coding are separately based on rate-compatible punctured convolution (RCPC) code scheme and rate-compatible punctured turbo (RCPT) code scheme. With optimum puncturing designation and suitable scheme of rate matching, these two UEP schemes can achieve intra-class unequal error protection, which makes the protection for source bits with different importance more accurate. Its real time implementation based on a TMS320C6416 digital signal processor is also presented. The experimental results suggest that this method have reasonable system complexity and short processing delay. 展开更多
关键词 channel coding unequal error protection convolution code turbo code
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Turbo decoding using two soft output values
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作者 李建平 潘申富 梁庆林 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期237-240,共4页
It is well known that turbo decoding always begins from the first component decoder and supposes that the apriori information is '0' at the first iterative decoding. To alternatively start decoding at two comp... It is well known that turbo decoding always begins from the first component decoder and supposes that the apriori information is '0' at the first iterative decoding. To alternatively start decoding at two component decoders, we can gain two soft output values for the received observation of an input bit. It is obvious that two soft output values comprise more sufficient extrinsic information than only one output value obtained in the conventional scheme since different start points of decoding result in different combinations of the a priori information and the input codewords with different symbol orders due to the permutation of an interleaver. Summarizing two soft output values for erery bit before making hard decisions, we can correct more errors due to their complement. Consequently, turbo codes can achieve better error correcting performance than before in this way. Simulation results show that the performance of turbo codes using the novel proposed decoding scheme can get a growing improvement with the increment of SNR in general compared to the conventional scheme. When the bit error probability is 10-5 , the proposed scheme can achieve 0.5 dB asymptotic coding gain or so under the given simulation conditions. 展开更多
关键词 turbo codes iterative decoding constituent encoder the extrinsic information interleaver.
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A proof of maximum contention-free property of interleavers for Turbo codes using permutation polynomials over integer rings
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作者 MA Xin-rui XU You-yun ZHANG Le 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第1期24-27,共4页
It is well known that interleavers play a critical role in Turbo coding/decoding schemes, and contention-free interleaver design has become a serious problem in the paraUelization of Turbo decoding, which is indispens... It is well known that interleavers play a critical role in Turbo coding/decoding schemes, and contention-free interleaver design has become a serious problem in the paraUelization of Turbo decoding, which is indispensable to meet the demands for high throughput and low latency in next generation mobile communication systems. This paper unveils the fact that interleavers based on permutation polynomials modulo N are contention-free for every window size W, a factor of the intedeaver length N, which, also called maximum contention-free interleavers. 展开更多
关键词 turbo codes Integer ring Permutation polynomial INTERLEAVER Maximum contention-free (MCF)
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Turbo Codes with Hybrid Interleaving Mode
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作者 李建平 Wang +2 位作者 Hongyuan Cai Dejun 《High Technology Letters》 EI CAS 2001年第4期50-53,共3页
In the investigation of turbo codes, either random interleavers or structured interleavers are used. Combined two kinds of interleavers in one turbo encoder, a hybrid interleaving mode is proposed in this paper. Compu... In the investigation of turbo codes, either random interleavers or structured interleavers are used. Combined two kinds of interleavers in one turbo encoder, a hybrid interleaving mode is proposed in this paper. Computer simulations show that the performance of turbo codes with the hybrid interleaving mode is better than that with the typical interleaving mode. 展开更多
关键词 turbo codes INTERLEAVER ENCODER
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Turbo Codes―A New PCCC Design
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作者 Spyridon K. Chronopoulos Giorgos Tatsis Panos Kostarakis 《Communications and Network》 2011年第4期229-234,共6页
Coding techniques have always been a major area of scientific interest. Due to this interest, many coding schemes were invented. Eventually, their implementation in various systems contributed in the evolvement of Wir... Coding techniques have always been a major area of scientific interest. Due to this interest, many coding schemes were invented. Eventually, their implementation in various systems contributed in the evolvement of Wireless Communications. A breakthrough was definitely Turbo coding. Particularly, the concept of joining two or more convolutional encoders in parallel (PCCC) or in serial (SCCC), along with the iterative decoding technique, literally raised the expectations of the anticipated BER performance. In fact, Concatenated Convolutional Codes clearly outperform convolutional codes. Moreover, various systems, either under development or either for future use, will have high standards. The previous systems should present exceptional tolerance of noise effects and consequently a low overall number of received errors. For this purpose a new PCCC design was developed. The system’s performance analysis, using an AWGN channel, showed better results for various iterations compared to other schemes such as typical PCCC, SCCC and finally a Convolutional encoder with a Viterbi decoder. 展开更多
关键词 turbo codes Convolutional codes SOVA SISO SCCC PCCC Random Interleavers Iterative Decoding APP Decoder PUNCTURING AWGN Noise Variance
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A channel- and QoS-adaptive turbo coded modulation architecture for mobile multimedia communication
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作者 左健存 Song Wentao +1 位作者 Luo Hanwen Xu Youyun 《High Technology Letters》 EI CAS 2009年第1期80-84,共5页
This paper proposed a cross-layer dual adaptive coded modulation architecture using turbo codes for mobile muhimedia communication, which simultaneously adapted to both the varying channel characteristics and the qual... This paper proposed a cross-layer dual adaptive coded modulation architecture using turbo codes for mobile muhimedia communication, which simultaneously adapted to both the varying channel characteristics and the quality of service (QoS) of various mobile multimedia services to increase the average system throughput substantially. A pragmatic channel-adaptive turbo coded modulation scheme, which comes within 2.5dB of the Shannon limit, was optimally designed, and then a QoS-adaptive scheme was superimposed to build the dual adaptive architecture. Simulation results show that the novel dual adaption reduces the difference with the fading channel capacity to 2dB when assuming different services occur in equal probability and the service duration follows the exponential distribution. 展开更多
关键词 dual adaption turbo coded modulation fading channels multimedia services spectral efficiency
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Joint Source-Channel Decoding Scheme for Image Transmission over Wireless Channel
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作者 Xiao Dong-liang Sun Hong 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期307-312,共6页
We improve the iterative decoding algorithm by utilizing the “leaked” residual redundancy at the output of the source encoder without changing the encoder structure for the noisy channel. The experimental results sh... We improve the iterative decoding algorithm by utilizing the “leaked” residual redundancy at the output of the source encoder without changing the encoder structure for the noisy channel. The experimental results show that using the residual redundancy of the compressed source in channel decoding is an effective method to improve the error correction performance. 展开更多
关键词 turbo code joint source-channel decoding residual redundancy arithmetic coding
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Channel Coding Based on Power Line Communication
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作者 Xiaojun Chen Yunxiao Zu 《Journal of Information Hiding and Privacy Protection》 2021年第3期101-107,共7页
This paper focuses on the forward error correction(FEC),the basic parameters determination of the RS convolution code,Turbo code and the LDPC code,and the corresponding encoding and decoding algorithm in power line co... This paper focuses on the forward error correction(FEC),the basic parameters determination of the RS convolution code,Turbo code and the LDPC code,and the corresponding encoding and decoding algorithm in power line communication(PLC)standard.Simulation experiment which is designed for narrow-band power line communication system based on OFDM is done.The coding using RS convolution code,Turbo code and LDPC code are compared,and further it is determined that which encoding method is more suitable for power line communication in China. 展开更多
关键词 OFDM communication RS convolution code turbo code LDPC code channel coding
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归零Turbo码的盲识别方法 被引量:15
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作者 张旻 陆凯 +1 位作者 李歆昊 吕全通 《系统工程与电子技术》 EI CSCD 北大核心 2016年第6期1423-1428,共6页
针对归零Turbo码的识别问题,提出一种有效的识别方法。该方法首先根据归零Turbo码的特殊结构,利用遍历矩阵列数的方式,寻找相关列均值最大值的位置,识别归零Turbo码长和起始点;其次,构建归零Turbo码的交织器识别模型,利用分层比对的方... 针对归零Turbo码的识别问题,提出一种有效的识别方法。该方法首先根据归零Turbo码的特殊结构,利用遍历矩阵列数的方式,寻找相关列均值最大值的位置,识别归零Turbo码长和起始点;其次,构建归零Turbo码的交织器识别模型,利用分层比对的方法得到交织置换关系,完成对交织器参数的识别。仿真实验表明,该方法在0.02的误码率条件下识别率仍能达到80%以上,验证了所提方法的有效性和鲁棒性。 展开更多
关键词 归零turbo 编码结构 交织识别 小区域检测 盲识别
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Turbo码中交织器的设计及其性能 被引量:6
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作者 叶永涛 张申如 +1 位作者 王庭昌 何维苗 《解放军理工大学学报(自然科学版)》 EI 2000年第3期37-40,共4页
在 Turbo码理论中 ,交织器的选择具有重要的地位。讨论了各种交织器的性能 ,给出了提高线性同余交织器有效自由距离的公式 ,提出了一种对称交织器的选取方法 ,并用 SOVA算法对行列交织器、随机交织器和所选定的交织器的性能进行了比较 ... 在 Turbo码理论中 ,交织器的选择具有重要的地位。讨论了各种交织器的性能 ,给出了提高线性同余交织器有效自由距离的公式 ,提出了一种对称交织器的选取方法 ,并用 SOVA算法对行列交织器、随机交织器和所选定的交织器的性能进行了比较 ,给出了基于距离谱的一些解释。仿真结果表明 ,用提出的方法所设计的交织器具有较好的性能 ,且具有实现上的优点。 展开更多
关键词 turbo 交织器 距离谱 SOVA算法 行列交织器
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Turbo码系统仿真及性能分析 被引量:6
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作者 李中捷 孙洪 +1 位作者 姚天任 D.Le Ruyet 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第3期76-78,共3页
在描述Turbo码的基本结构的基础上 ,对Turbo码进行计算机仿真研究 ,通过系统仿真讨论影响Turbo码性能的一些主要因素 。
关键词 信道编码 turbo 迭代译码 系统仿真 信息序列分组长度 信噪比 编码器
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