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LDGM codes for channel coding and joint source-channel coding of correlated sources

EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2005年第6期2005卷 942-953页

作者： Zhong, W Garcia-Frias, J Univ Delaware Dept Elect & Comp Engn Newark DE 19716 USA

We propose a coding scheme based on the use of systematic linear codes with low-density generator matrix (LDGM codes) for channel coding and joint source-channel coding of multiterminal correlated binary sources. In both cases, the structures of the LDGM encoder and decoder are shown, and a concatenated scheme aimed at reducing the error floor is proposed. Several decoding possibilities are investigated, compared, and evaluated. For different types of noisy channels and correlation models, the resulting performance is very close to the theoretical limits.

关键词： channel coding LDPC codes LDGM codes iterative decoding correlated sources joint source-channel coding

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Mismatched source Transition Probability Matrix for Adaptive MAP Decoding in MPEG-4 Imagery Wireless Transmission Systems

Mismatched Source Transition Probability Matrix for Adaptive...

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20th IEEE Symposium on Personal, Indoor and Mobile Radio Communications

作者： Mahapakulchai, Srijidtra Charoenlarpnopparut, Chalie Hasajitto, Siriwat Kasetsart Univ Dept Elect Engn Bangkok Thailand Thammasat Univ Sch Informat Sirindhom Int Inst Tech Comp & Commun Tech Bangkok Thailand

ISBN: (纸本)9781424451234

Here, we design the efficient technique of transmitting the source transition probability matrix (STPM) by accompanied with the lowest frequency subband (LFS). The entries of this stochastic matrix are adaptively computed by applying the first order Markov model with MPEG-4 zerotree sequences. Because of channel disturbances, we obtain the mismatched STPM at the ML-Viterbi receiver and then employ it for newly computed branch metrics at the MAP source-controlled channel decoder. For analysis, we also evaluate the residual redundancies for both the "Lena" and the "Barbara" images. The system performance is summarized in term of both PSNR (dB) and WER for three types of slow flat Rician fading channels. In the mismatched STPM simulation results, we still obtain the most PSNR improvement of about 0.14 dB.

关键词： joint source-channel coding MAP decoder Markov model Residual redundancy Ring convolutional codes Rician fading channels

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joint REsourceS ALLOCATION FOR COOPERATIVE VIDEO TRANSMISSION

JOINT RESOURCES ALLOCATION FOR COOPERATIVE VIDEO TRANSMISSIO...

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16th IEEE International Conference on Image Processing

作者： Xiao, Hongjiang Dai, Qionghai Ji, Xiangyang Tsinghua Univ Dept Automat Beijing 100084 Peoples R China

ISBN: (纸本)9781424456536

This paper proposes a cooperative multiple-input multiple-output (MIMO) architecture to transmit the video reliably. By exploring the configurable resources of the scalable video and the coded MIMO system, we further propose a novel joint source-channel coding (JSCC) framework with optimal tradeoff among diversity, multiplexing and coding gains. In this framework, the concatenated low-density parity-check codes (LDPC) and diversity-embedded space-time block codes (DE-STBC) provide double unequal error protection for the video layers, and the STBCs switching enables the adaptability to the varying channel. Experiments demonstrate the superiority of cooperative architecture and the effectiveness of our JSCC algorithm.

关键词： Cooperative transmission joint source-channel coding diversity-multiplexing-coding gain tradeoff scalable video coding

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Distributed Transmission of Functions of Correlated sources over a Fading Multiple Access channel

Distributed Transmission of Functions of Correlated Sources ...

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47th Annual Allerton Conference on Communication, Control, and Computing

作者： Rajesh, R. Sharma, Vinod Indian Inst Sci Dept ECE Bangalore 560012 Karnataka India

ISBN: (纸本)9781424458707

In this paper we address the problem of distributed transmission of functions of correlated sources over a fast fading multiple access channel (MAC). This is a basic building block in a hierarchical sensor network used in estimating a random field where the cluster head is interested only in estimating a function of the observations. The observations are transmitted to the cluster head through a fast fading MAC. We provide sufficient conditions for lossy transmission when the encoders and decoders are provided with partial information about the channel state. Furthermore signal side information maybe available at the encoders and the decoder. Various previous studies are shown as special cases. Efficient joint-source channel coding schemes are discussed for transmission of discrete and continuous alphabet sources to recover function values.

关键词： joint source-channel coding Fading MAC Power allocation Partial channel state information Graph coloring Correlated sources

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Control over Low-Rate Noisy channels

Control over Low-Rate Noisy Channels

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作者： LEI BAO KTH Royal Institute of Technology

学位级别：博士

Networked embedded control systems are present almost everywhere. A recent trend is to introduce radio communication in these systems to increase mobility and flex- ibility. Network nodes, such as the sensors, are often simple devices with limited computing and transmission power and low storage capacity, so an important prob- lem concerns how to optimize the use of resources to provide sustained overall sys- tem performance. The approach to this problem taken in the thesis is to analyze and design the communication and control application layers in an integrated man- ner. We focus in particular on cross-layer design techniques for closed-loop control over non-ideal communication channels, motivated by future control systems with very low-rate and highly quantized sensor communication over noisy links. Several fundamental problems in the design of source–channel coding and optimal control for these systems are discussed. The thesis consists of three parts. The first and main part is devoted to the joint design of the coding and control for linear plants, whose state feedback is trans- mitted over a finite-rate noisy channel. The system performance is measured by a finite-horizon linear quadratic cost. We discuss equivalence and separation proper- ties of the system, and conclude that although certainty equivalence does not hold in general it can still be utilized, under certain conditions, to simplify the overall design by separating the estimation and the control problems. An iterative opti- mization algorithm for training the encoder–controller pairs, taking channel errors into account in the quantizer design, is proposed. Monte Carlo simulations demon- strate promising improvements in performance compared to traditional approaches. In the second part of the thesis, we study the rate allocation problem for state feedback control of a linear plant over a noisy channel. Optimizing a time-varying communication rate, subject to a maximum average-rate constraint, can b

关键词： sensor networks linear quadratic cost stochastic control joint source-channel coding joint coding and control rate allocation soft source decoding

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A NOVEL ERROR RESILIENT joint sourcechannel coding SCHEME FOR IMAGE TRANSMISSION OVER ERROR PRONE channelS

A NOVEL ERROR RESILIENT JOINT SOURCECHANNEL CODING SCHEME FO...

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2009 2nd IEEE International Conference on Broadband Network & Multimedia Technology（IC-BNMT2009）

作者： Xue Guodong 1,Hao Chenxi 2,Zhang Wenbo 1,Zou Jun 3 1.School of information and communication engineering 2.School of computer science and technology Beijing University of Posts and Telecommunications,Beijing,China 3.IBM China Software Development Laboratory (CDL),Beijing,China

In this paper,we proposed a double-level error resilient joint source-channel coding scheme for image ***,we inserted one coordinative component named error resilient entropy coding (EREC) between source coding and channel coding to achieve additional error resilient *** on the novel architecture,we proved that,in the aspects of computational complexity,coding redundancy and furthermore the decoding performance of image transmission,our scheme outperformed either separate source and channel coding scheme or joint source-channel coding scheme with synchronization words.

关键词： double-level error resilient capability joint source-channel coding image transmission error prone channels

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Comments on "Optimal Erasure Protection for Scalably Compressed Video Streams With Limited Retransmission"

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2009年第1期18卷 214-216页

作者： Dumitrescu, Sorina McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada

In order to prove a key result for their development (Lemma 2), Taubman and Thic need the assumption that the upper boundary of the convex hull of the channel coding probability-redundancy characteristic is sufficiently dense. Since a floor value for the density level for which the claim to hold is not specified, it is not clear whether their lemma applies to practical situations. In this correspondence, we show that the constraint of sufficient density can be removed, and, thus, we validate the conclusion of the lemma for any scenario encountered in practice.

关键词： joint source-channel coding unequal erasure protection

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Iterative decoder design for joint source-channel LDPC coding

Iterative decoder design for joint source-channel LDPC codin...

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International Conference on Computer as a Tool (EUROCON 2005)

作者： Lakovic, K Tian, T Villasenor, J Univ Calif Los Angeles Los Angeles CA 90024 USA

ISBN: (纸本)142440049X

We consider joint source-channel coding with variable length codes (VLCs) and LDPC codes. We propose an iterative source-channel decoding system, which involves message passing between a soft-input-soft-output VLC decoder and an LDPC decoder. The proposed system utilizes the residual redundancy of the variable length code during the iterative decoding process, and is expected to exhibit decoding convergence at a lower SNR relative to the system in which source and channel decoding are performed separately. We present computer simulation results that confirm the expected gain of the proposed system.

关键词： joint source-channel coding LDPC codes variable length codes

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Correlation, coding, and cooperation in wireless sensor networks

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3rd International Workshop on Algorithmic Aspects of Wireless Sensor Networks

作者： Agnihotri, Samar Nuggehalli, Pavan Jamadagni, H. S. Indian Inst Sci CEDT Bangalore 560012 Karnataka India

ISBN: (纸本)9783540778707

We consider a single-hop data-gathering sensor network, consisting of a set of sensor nodes that transmit data periodically to a base-station. We are interested in maximizing the lifetime of this network. With our definition of network lifetime and the assumption that the radio transmission energy consumption forms the most significant portion of the total energy consumption at a sensor node, we attempt to enhance the network lifetime by reducing the transmission energy budget of sensor nodes by exploiting three system-level opportunities. We pose the problem of maximizing lifetime as a max-min optimization problem subject to the constraint of successful data collection and limited energy supply at each node. This turns out to be an extremely difficult optimization to solve. To reduce the complexity of this problem, we allow the sensor nodes and the base-station to interactively communicate with each other and employ instantaneous decoding at the base-station. The chief contribution of the paper is to show that the computational complexity of our problem is determined by the complex interplay of various system-level opportunities and challenges.

关键词： sensor networks lifetime maximization multi-access networks joint source-channel coding data correlation Slepian-Wolf coding scheduling

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Dynamic rate allocation with variable quantization in multi-sensor Wyner-Ziv video coding systems

Dynamic rate allocation with variable quantization in multi-...

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3rd IEEE International Symposium on Control, Communications and Signal Processing (ISCCSP 2008)

作者： Yaacoub, C. Farah, J. Pesquet-Popescu, B. Holy Spirit Univ Kaslik Fac Sci & Comp Engn Jounieh Lebanon Ecole Natl Super Telecommun Bretagne Dept Signal & Image Proc Paris France

ISBN: (纸本)9781424416875

In this paper, we present a novel algorithm for dynamic quantization in distributed Wyner-Ziv video coding. In contrast with previous work where the quantization parameter is fixed and a feedback channel is used, our proposed technique relies on theoretical calculations to jointly determine the number of quantization levels along with a suitable compression rate for each video frame. It employs a cross-layer approach that dynamically allocates unequal transmission rates for different users by taking into account the amount of motion in the captured video scenes on one hand and the transmission conditions for each sensor on the other. The application of this algorithm in a wireless video sensor network shows a significant improvement in the system performance when compared to a traditional system that allocates equal channel resources with a fixed quantization parameter.

关键词： dynamic quantization joint source-channel coding rate allocation wireless video sensor network Wyner-Ziv coding

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