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用编码·解码理论试析舞蹈作品的创作与编排
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作者 吴盼尔雅 《艺海》 2015年第9期48-50,共3页
在全民健身的时代,舞蹈艺术看似逐渐普及化与大众化,然而,广泛流传的实际上是打着舞蹈名号的健身操舞,并不是真正意义的舞蹈作品。舞蹈作品出现止于圈内,流于泛泛的发展现状。本文试用斯图亚特·霍尔的编码·解码理论分析舞蹈... 在全民健身的时代,舞蹈艺术看似逐渐普及化与大众化,然而,广泛流传的实际上是打着舞蹈名号的健身操舞,并不是真正意义的舞蹈作品。舞蹈作品出现止于圈内,流于泛泛的发展现状。本文试用斯图亚特·霍尔的编码·解码理论分析舞蹈作品的产生过程,研究舞蹈作品止于圈内的原因,从中探析舞蹈作品的创作与编排的方式方法。 展开更多
关键词 编码·解码 斯图亚特·霍尔 舞蹈作品 创作与编排
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从“编码·解码”理论浅析电影《花木兰》 被引量:1
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作者 李夏 《新闻研究导刊》 2017年第1期164-164,共1页
迪士尼公司出品的电脑动画电影《花木兰》于1998年6月19日在美国上映,随后在全球46个国家和地区先后上映,取得了304320254美元的票房,这是美国电影中取材于中国文学的作品,给笔者留下了深刻的印象。其中,关于西方价值观和东方文化的相... 迪士尼公司出品的电脑动画电影《花木兰》于1998年6月19日在美国上映,随后在全球46个国家和地区先后上映,取得了304320254美元的票房,这是美国电影中取材于中国文学的作品,给笔者留下了深刻的印象。其中,关于西方价值观和东方文化的相互交流与碰撞的探讨从未断绝。本文将基于霍尔的"编码·解码"理论来分析《花木兰》电影中的影视文化。 展开更多
关键词 迪士尼电影《花木兰》 编码·解码 影视文化
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General and robust voxel feature learning with Transformer for 3D object detection 被引量:1
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作者 LI Yang GE Hongwei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期51-60,共10页
The self-attention networks and Transformer have dominated machine translation and natural language processing fields,and shown great potential in image vision tasks such as image classification and object detection.I... The self-attention networks and Transformer have dominated machine translation and natural language processing fields,and shown great potential in image vision tasks such as image classification and object detection.Inspired by the great progress of Transformer,we propose a novel general and robust voxel feature encoder for 3D object detection based on the traditional Transformer.We first investigate the permutation invariance of sequence data of the self-attention and apply it to point cloud processing.Then we construct a voxel feature layer based on the self-attention to adaptively learn local and robust context of a voxel according to the spatial relationship and context information exchanging between all points within the voxel.Lastly,we construct a general voxel feature learning framework with the voxel feature layer as the core for 3D object detection.The voxel feature with Transformer(VFT)can be plugged into any other voxel-based 3D object detection framework easily,and serves as the backbone for voxel feature extractor.Experiments results on the KITTI dataset demonstrate that our method achieves the state-of-the-art performance on 3D object detection. 展开更多
关键词 3D object detection self-attention networks voxel feature with Transformer(VFT) point cloud encoder-decoder
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CHANNEL ESTIMATION FOR ITERATIVE DECODING OVER FADING CHANNELS 被引量:1
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作者 K.H.Sayhood 《Journal of Electronics(China)》 2002年第4期346-355,共10页
A method of coherent detection and channel estimation for punctured convolutional coded binary Quadrature Amplitude Modulation (QAM) signals transmitted over a frequency-flat Rayleigh fading channels used for a digita... A method of coherent detection and channel estimation for punctured convolutional coded binary Quadrature Amplitude Modulation (QAM) signals transmitted over a frequency-flat Rayleigh fading channels used for a digital radio broadcasting transmission is presented. Some known symbols are inserted in the encoded data stream to enhance the channel estimation process.The pilot symbols are used to replace the existing parity symbols so no bandwidth expansion is required. An iterative algorithm that uses decoding information as well as the information contained in the known symbols is used to improve the channel parameter estimate. The scheme complexity grows exponentially with the channel estimation filter length. The performance of the system is compared for a normalized fading rate with both perfect coherent detection (corresponding to a perfect knowledge of the fading process and noise variance) and differential detection of Differential Amplitude Phase Shift Keying (DAPSK). The tradeoff between simplicity of implementation and bit-error-rate performance of different techniques is also compared. 展开更多
关键词 CODES Iterative decoding Channel estimation
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Frame-bitrate-change based steganography for voice-over-IP 被引量:4
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作者 刘进 田晖 周可 《Journal of Central South University》 SCIE EI CAS 2014年第12期4544-4552,共9页
Steganography based on bits-modification of speech frames is a kind of commonly used method, which targets at RTP payloads and offers covert communications over voice-over-IP(Vo IP). However, direct modification on fr... Steganography based on bits-modification of speech frames is a kind of commonly used method, which targets at RTP payloads and offers covert communications over voice-over-IP(Vo IP). However, direct modification on frames is often independent of the inherent speech features, which may lead to great degradation of speech quality. A novel frame-bitrate-change based steganography is proposed in this work, which discovers a novel covert channel for Vo IP and introduces less distortion. This method exploits the feature of multi-rate speech codecs that the practical bitrate of speech frame is identified only by speech decoder at receiving end. Based on this characteristic, two steganography strategies called bitrate downgrading(BD) and bitrate switching(BS)are provided. The first strategy substitutes high bit-rate speech frames with lower ones to embed secret message, which introduces very low distortion in practice, and much less than other bits-modification based methods with the same embedding capacity. The second one encodes secret message bits into different types of speech frames, which is an alternative choice for supplement. The two strategies are implemented and tested on our covert communication system Steg Vo IP. The experiment results show that our proposed method is effective and fulfills the real-time requirement of Vo IP communication. 展开更多
关键词 covert communication steganography multi-rate speech codec voice-over-IP(VOIP)
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Optical encryption with cascaded fractional wavelet transforms 被引量:1
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作者 BAO Liang-hua CHEN Lin-fei ZHAO Dao-mu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第8期1431-1435,共5页
On the basis of fractional wavelet transform, we propose a new method called cascaded fractional wavelet transform to encrypt images. It has the virtues of fractional Fourier transform and wavelet transform. Fractiona... On the basis of fractional wavelet transform, we propose a new method called cascaded fractional wavelet transform to encrypt images. It has the virtues of fractional Fourier transform and wavelet transform. Fractional orders, standard focal lengths and scaling factors are its keys. Multistage fractional Fourier transforms can add the keys easily and strengthen information se-curity. This method can also realize partial encryption just as wavelet transform and fractional wavelet transform. Optical reali-zation of encryption and decryption is proposed. Computer simulations confirmed its possibility. 展开更多
关键词 Wavelet transform (WT) Cascaded fractional wavelet transform (CFWT) ENCRYPTION DECRYPTION
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A Decode-and-Forward Scheme for LDPC Coded Three-Way Relay Fading Channels 被引量:2
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作者 YE Xia GAO Feifei 《China Communications》 SCIE CSCD 2015年第8期46-54,共9页
In this paper a low-density pairwise check(LDPC) coded three-way relay system is considered, where three user nodes desire to exchange messages with the help of one relay node. Since physical-layer network coding is a... In this paper a low-density pairwise check(LDPC) coded three-way relay system is considered, where three user nodes desire to exchange messages with the help of one relay node. Since physical-layer network coding is applied, two time slots are sufficient for one round information exchange. In this paper, we present a decode-and-forward(DF) scheme based on joint LDPC decoding for three-way relay channels, where relay decoder partially decodes the network code rather than fully decodes all the user messages. Simulation results show that the new DF scheme considerably outperforms other common schemes in three-way relay fading channels. 展开更多
关键词 three-way relay channel physicallayer network coding LDPC codes decode-and forward
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In-Network Puncturing for Delay-Efficient Rate Control of Distributed Video Coding in Wireless Video Sensor Networks 被引量:1
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作者 Zhang Haitao Ma Huadong 《China Communications》 SCIE CSCD 2012年第6期45-54,共10页
Wyner-Ziv Video Coding (WZVC) is considered as a promising video coding scheme for Wireless Video Sensor Networks (WVSNs) due to its high compression efficiency and error resilience functionalities, as well as its... Wyner-Ziv Video Coding (WZVC) is considered as a promising video coding scheme for Wireless Video Sensor Networks (WVSNs) due to its high compression efficiency and error resilience functionalities, as well as its low encoding complex- ity. To achieve a good Rate-Distortion (R-D) per- formance, the current WZVC paradi^prls usually a- dopt an end-to-end rate control scheme in which the decoder repeatedly requests the additional deco- ding data from the encoder for decoding Wyner-Ziv frames. Therefore, the waiting time of the additional decoding data is especially long in multihop WVSNs. In this paper, we propose a novel pro- gressive in-network rate control scheme for WZVC. The proposed in-network puncturing-based rate control scheme transfers the partial channel codes puncturing task from the encoder to the relay nodes. Then, the decoder can request the addition- al decoding data from the relay nodes instead of the encoder, and the total waiting time for deco- ding Wyner-Ziv frames is reduced consequently. Simulation results validate the proposed rate con- trol scheme. 展开更多
关键词 wireless video sensor networks dis-tributed video coding WZVC rate control delay-efficient
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FAST ALGORITHM FOR REED-SOLOMON CODE AND THE HARDWARE IMPLEMENTATION
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作者 张毓忠 滕建辅 周长华 《Transactions of Tianjin University》 EI CAS 1995年第1期83+80-83,共5页
This paper described a signal processor for the Reed-Solomon (R-S) code using micro-programming. For the purpose of fast encoding and decoding,a formula for detecting two errors is derived, and the Qian search method... This paper described a signal processor for the Reed-Solomon (R-S) code using micro-programming. For the purpose of fast encoding and decoding,a formula for detecting two errors is derived, and the Qian search method for the decoding process is improved. The number of searches is significantly reduced from 256 to 4. At the same time, the circuit is simplified and the speed is increased. For the convenience of programming, a micro-programming compiling package is developed. The package can be used for programming of different formats of R-S code signal processors of DAB, MD and DCC. The software and the hardware can be used for error correcting, error detecting and error compensation of different formats of R-S code. 展开更多
关键词 R-S code ENCODING DECODING Qian search
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Simple optical decryption based on a modified joint transform correlator technique
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作者 王怀彬 王天佐 袁晓聪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期203-205,共3页
A new encryption/decryption system for optical information security is proposed in this paper. We used an iterative Fourier transform algorithm to optimize the encrypted hologram as well as the decryption key as phase... A new encryption/decryption system for optical information security is proposed in this paper. We used an iterative Fourier transform algorithm to optimize the encrypted hologram as well as the decryption key as phase-only elements. The optical decryption was implemented by superimposing the encrypted hologram and the decryyption key in a simple optical setup. Numerical simulation and optical experiment have confirmed the proposed technique as a simple and easy implementation for optical decryption, demonstrating potential applications in optical information security verification. 展开更多
关键词 computer generated holograms CORRELATOR ENCRYPTION/DECRYPTION
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WIRELESS FLOPPY DISK DRIVE USING TURBO CODEC IN HOME AND OFFICE WIRELESS LAN
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作者 Kazi Takpaya 《Journal of Electronics(China)》 2003年第6期446-450,共5页
A wireless floppy disk drive is proposed for home and office wireless local area network. The proposed floppy drive uses turbo coding-decoding in the transceiver PHYsical layer (PHY) to improve system performance. The... A wireless floppy disk drive is proposed for home and office wireless local area network. The proposed floppy drive uses turbo coding-decoding in the transceiver PHYsical layer (PHY) to improve system performance. The data transmission rate is about 11 Mbps. The covered distance is 30 meters in obstructed environment and 100 m in free space. 展开更多
关键词 WLAN Turbo coding-decoding Wireless floppy disk drive Transceiver PHYsical layer
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LOW-COMPLEXITY REDUNDANCY INSERTION IN MULTIPLE DESCRIPTION CODING
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作者 Yang Rener Li Jinxiang Wen Huafeng 《Journal of Electronics(China)》 2008年第3期409-414,共6页
Multiple description coding has recently been proposed as a joint source and channel coding to solve the problem of robust image transmission over unreliable network, and it can offer a variety of tradeoff between sig... Multiple description coding has recently been proposed as a joint source and channel coding to solve the problem of robust image transmission over unreliable network, and it can offer a variety of tradeoff between signal redundancy and transmission robustness. In this letter, a novel pre- and post-processing method with flexible redundancy insertion for polyphase downsampling multiple de- scription coding is presented. The proposed method can be implemented as pre- and post-processing to all standards for image and video communications, with obvious advantages. Simulation results show that this approach can reduce the computational complexity while provide a flexible redundancy in- sertion to make the system robust for any packet loss situation over different networks. 展开更多
关键词 Multiple description image coding Polyphase downsampling Redundancy insertion
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A Concatenated ML Decoder for ST/SFBC-OFDM Systems in Double Selective Fading Channels
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作者 李明齐 张文军 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期15-20,共6页
This paper presented a concatenated maximum-likelihood (ML) decoder for space-time/space-frequency block coded orthogonal frequency diversion multiplexing (ST/SFBC-OFDM) systems in double selective fading channels. Th... This paper presented a concatenated maximum-likelihood (ML) decoder for space-time/space-frequency block coded orthogonal frequency diversion multiplexing (ST/SFBC-OFDM) systems in double selective fading channels. The proposed decoder first detects space-time or space-frequency codeword elements separately. Then, according to the coarsely estimated codeword elements, the ML decoding is performed in a smaller constellation element set to searching final codeword. It is proved that the proposed decoder has optimal performances if and only if subchannels are constant during a codeword interval. The simulation results show that the performances of proposed decoder is close to that of the optimal ML decoder in severe Doppler and delay spread channels. However, the complexity of proposed decoder is much lower than that of the optimal ML decoder. 展开更多
关键词 wireless conmmunications OFDM space-time coding ML decoding
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THE UNIFICATION OF DIFFERENTIAL ENCODING AND DECODING ALGORITHM FOR VARIOUS SIGNALS
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作者 Liu Shuangping Wen Xiang Jin Liang 《Journal of Electronics(China)》 2007年第5期600-606,共7页
Many monographs point out that differential encoding and decoding is necessary for ef- fectual information transmission against phase ambiguity while seldom discuss the reason why phase ambiguity will emerge inevitabl... Many monographs point out that differential encoding and decoding is necessary for ef- fectual information transmission against phase ambiguity while seldom discuss the reason why phase ambiguity will emerge inevitably.Available algorithms are specially designed for certain modulation scheme;these algorithms cannot satisfy the requirement of soft-defined radio,which perhaps demands a uniform algorithm for different modulations.This paper proposes a new opinion on phase ambiguity from the view of probability.This opinion believes that modulating symbol sequence can affect,at optimum sampling epoch,the modulated waveform as oscillating carrier has done,and so the stochastic sequence leads to phase ambiguity.Based on a general signal model,this paper also puts forward a novel universal algorithm,which is suitable for different signals,even some new ones,by configuring several parameters. 展开更多
关键词 Soft-defined radio Differential encoding and decoding Phase ambiguity
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Design of bilayer lengthened LDPC codes over expanded graph for relay channels
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作者 刘洋 Li Ying Su Yuping 《High Technology Letters》 EI CAS 2015年第4期494-499,共6页
This paper presents a low complexity optimized algorithm for design of bilayer lengthened LDPC(BL-LDPC) code for decode-and-forward relay system.The design is performed over the expanded graph of the BL-LDPC code,whic... This paper presents a low complexity optimized algorithm for design of bilayer lengthened LDPC(BL-LDPC) code for decode-and-forward relay system.The design is performed over the expanded graph of the BL-LDPC code,which consists of the original bilayer graph and the extra added relaygenerated parity check bits.To build up our proposed optimized algorithm,we present a modified Gaussian approximation algorithm for the expanded structure of the BL-LDPC code.Then using the proposed optimized algorithm,we find the optimum overall expanded graph of the BL-LDPC code.Simulation results show that the BL-LDPC codes obtained by our proposed optimized algorithm have excellent bit-error-rate performances and small gaps between the convergence thresholds and the theoretical limits when transmitted over the additive white Gaussian noise channels. 展开更多
关键词 bilayer LDPC codes relay channel DECODE-AND-FORWARD Gaussian approxima- tion channel capacity
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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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Screen image sequence compression method utilizing adaptive block size coding and hierarchical GOP structure
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作者 武星 梅亮 +2 位作者 袭奇 张申生 陈延伟 《Journal of Central South University》 SCIE EI CAS 2010年第4期786-794,共9页
To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra... To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra-frame and inter-frame coding modes.The intra-frame coding is a rate-distortion optimized adaptive block size that can be also used for the compression of a single screen image.The inter-frame coding utilizes hierarchical group of pictures(GOP) structure to improve system performance during random accesses and fast-backward scans.Experimental results demonstrate that the proposed CABHG method has approximately 47%-48% higher compression ratio and 46%-53% lower CPU utilization than professional screen image sequence codecs such as TechSmith Ensharpen codec and Sorenson 3 codec.Compared with general video codecs such as H.264 codec,XviD MPEG-4 codec and Apple's Animation codec,CABHG also shows 87%-88% higher compression ratio and 64%-81% lower CPU utilization than these general video codecs. 展开更多
关键词 screen image sequence compression adaptive block size hierarchical GOP structure intra-frame coding inter-frame coding
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New Applications of EXIT Chart for Iterative Decoding Systems
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作者 宫丰奎 葛建华 李兵兵 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第1期35-39,共5页
Applications on iterative control and multiple input multiple output (MIMO) system were developed. Two new charts derived from extrinsic information transfer (EXIT) chart were employed as the designing tools, which ar... Applications on iterative control and multiple input multiple output (MIMO) system were developed. Two new charts derived from extrinsic information transfer (EXIT) chart were employed as the designing tools, which are called as output mutual information chart with defined iterative degree (DID) chart and near optimum output mutual information (NOMI) chart respectively. Different from the EXIT chart, they can show the iterative performance on the whole signal-to-noise ratio range with one single curve, whereas computation complexity is greatly reduced compared with conventional bit error ratio (BER) performance curve. The iterative control was implemented according to a near-optimum iterative degree vector determined by NOMI chart, the reasonability of uncertain parameters was analyzed in one MIMO system. The concepts were illustrated based on bit-interleaved coded modulation with iterative decoding (BICM-ID). 展开更多
关键词 extrinsic information transfer chart bit-interleaved coded modulation iterative decoding multiple input multiple output
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Side information refinement in distributed video coding
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作者 刘鸿彬 Zhao Debin +1 位作者 Ma Siwei Gao Wen 《High Technology Letters》 EI CAS 2012年第4期423-427,共5页
Side information (SI) is one of the key issues in distributed video coding (DVC) and affects the compression performance of DVC largely. This paper proposes an SI refinement algorithm, in which the Wyner-Ziv (WZ... Side information (SI) is one of the key issues in distributed video coding (DVC) and affects the compression performance of DVC largely. This paper proposes an SI refinement algorithm, in which the Wyner-Ziv (WZ) frame is split into two parts based on checkerboard pattern, and the two parts are encoded independently but decoded sequentially. In the decoding process, the part 1 is first decoded with the initial SI and partially decoded part (PDP) 1 is used to improve the motion vectors (MVs) and SI of both parts. At the next stage, the part 2 is decoded with the improved SI and PDP 2 is used to further refine MVs of the part 2. Then, SI of both parts are further refined. Simulation results show that the proposed algorithm can improve the peak signal to noise ratio (PSNR) by up to 1.43 dB when compared with traditional DVC codec. 展开更多
关键词 distributed video coding (DVC) side information (SI) checkerboard pattern
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Network Coding Based on Linear Block Codes for Multi-source Cooperative Relaying Networks
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作者 李宗艳 李世银 李德亮 《Journal of Donghua University(English Edition)》 EI CAS 2013年第6期504-509,共6页
In order to improve link performance of future wireless relay networks,a network coding scheme with linear block codes was proposed,which could be deployed in a relay network consisting of multi-source sending data to... In order to improve link performance of future wireless relay networks,a network coding scheme with linear block codes was proposed,which could be deployed in a relay network consisting of multi-source sending data to a common base station(BS) with the assistance of one relay node.At BS,an iterative decoding structure between one cooperative decoder and a number of single-source decoders was established using the relayed network codes and source codes.Further,the extrinsic information transfer(EXIT) chart technique was used to predict and analyze the convergence behavior of iterative decoder.The analysis and simulation results show that the bit error ratio(BER) performance of the proposed scheme outperforms reference scheme under different relay network coding matrices.Compared with a reference scheme without the multisource cooperation,the proposed scheme can obtain network coding gain from the relay network while not reduce its code rate. 展开更多
关键词 multiple access relay channel iterative decoding extrinsic information transfer chart: converfence
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