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combined source-channel coding schemes for video transmission over an additive white Gaussian noise channel

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2000年第6期18卷 880-890页

作者： Bystrom, M Modestino, JW Drexel Univ Ctr Telecommun & Informat Networking ECE Dept Philadelphia PA 19104 USA Rensselaer Polytech Inst Ctr Image Proc Res Troy NY 12180 USA Rensselaer Polytech Inst ECSE Dept Troy NY 12180 USA

In recent gears there has been an increased interest in the transmission of digital video over real-world transmission media, such as the direct broadcast satellite (DBS) channel, Video transmitted over such a channel is subject to degradation due, in part, to additive white Gaussian noise (AWGN). Some form of forward error control (FEC) coding may be applied in order to reduce the effect of the noise on the transmitted bitstream;however, determination of the appropriate level of FEC coding is generally an unwieldy and computationally intensive problem, as it may depend upon a variety of parameters such as the type of video, the available bandwidth, and the channel SNR, More specifically, a combined source-channel coding approach is necessary in optimally allocating rate between source and channel coding subject to a fixed constraint on overall transmission bandwidth, In this paper we develop a method of optimal bit allocation under the assumption that the distortion is additive and independent on a frame-by-frame basis. A set of universal operational distortion-rate characteristics is developed which balances the tradeoff between source coding accuracy and channel error protection for a fixed overall transmission rate and provides the basis for the optimal bit allocation approach, The results for specific source and channel coding schemes show marked improvement over suboptimum choices of channel error protection, In addition, we show that our results approach information-theoretic performance bounds which are developed in this work.

关键词： combined source-channel coding operational rate allocation

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Transmission of analog signals using multicarrier modulation: A combined source-channel coding approach

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IEEE TRANSACTIONS ON COMMUNICATIONS 1996年第11期44卷 1432-1443页

作者： Ho, KP Kahn, JM UNIV CALIF BERKELEY DEPT EECS BERKELEY CA 94720 USA

We have proposed and analyzed a combined source-channel coding scheme using multicarrier modulation. By changing the power and modulation of subchannels carrying different bits of the quantized signal, the channel-induced distortion can he minimized. We derive an algorithm for the allocation of power among subchannels. Analog sources quantized by scalar and vector quantizers are considered. For a Gaussian source scalar-quantized to 8 b, multicarrier transmission yields a 13 dB improvement of signal-to-distortion ratio over a single-carrier system. Quantizers having a smaller number of bits geld smaller improvements. We consider both full-search and binary tree-search vector quantizers using a natural binary coding scheme. For a vector quantizer using 2 b/sample, multicarrier transmission yields an improvement in signal-to-distortion ratio that lies between 0.3 and 0.8 dB, depending an the quantizer-design.

关键词： combined source-channel coding ANALOG SIGNALS quantizer signal-to-distortion ratio subchannel

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OPTIMAL DETECTION OF DISCRETE MARKOV sourceS OVER DISCRETE MEMORYLESS channelS - APPLICATIONS TO combined source-channel coding

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IEEE TRANSACTIONS ON INFORMATION THEORY 1994年第1期40卷 186-193页

作者： PHAMDO, N FARVARDIN, N UNIV MARYLAND DEPT ELECT ENGN COLLEGE PK MD 20742 USA UNIV MARYLAND INST SYST RES COLLEGE PK MD 20742 USA

We consider the problem of detecting a discrete Markov source which is transmitted across a discrete memoryless channel. Two maximum a posteriori (MAP) formulations are considered: i) a sequence MAP detection in which the objective is to determine the most probable transmitted sequence given the observed sequence and ii) an instantaneous MAP detection which is to determine the most probable transmitted symbol at time n given all the observations prior to and including time n. The solution to the first problem results in a ''Viterbi-like'' implementation of the MAP detector (with large delay) while the latter problem results in a recursive implementation (with no delay). For the special case of the binary symmetric Markov source and binary symmetric channel, simulation results are presented and an analysis of these two systems yields explicit critical channel bit error rates above which the MAP detectors become useful. Applications of the MAP detection problem in a combined source-channel coding system are considered. Here, it is assumed that the source is highly correlated and that the source encoder (in our case, a vector quantizer (VQ) fails to remove all of the source redundancy. The remaining redundancy at the output of the source encoder is referred to as the ''residual'' redundancy. It is shown, through simulation, that the residual redundancy can be used by the MAP detectors to combat channel errors. For small block sizes, the proposed system beats Farvardin and Vaishampayan's channel-optimized VQ by wide margins. Finally, it is shown that the instantaneous MAP detector can be combined with the VQ decoder to form an approximate minimum mean-squared error decoder.

关键词： MARKOV source DISCRETE MEMORYLESS channel MAP DETECTION combined source-channel coding

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On combined ring convolutional coded quantisation and CPM for joint source/channel coding

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EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS 2008年第4期19卷 443-453页

作者： Lin, Zihuai Aulin, Tor Univ Sydney Sch Elect & Informat Engn Sydney NSW 2006 Australia Chalmers Univ Technol Dept Comp Engn Telecommun Theory Grp SE-41296 Gothenburg Sweden

A new trellis-based coded quantisation scheme using ring convolutional codes is presented. When it is combined with trellis-coded continuous phase modulation (TCCPM) with convolutional codes over rings, a powerful joint source and channel coding (JSCC) scheme can be formed. We investigate the additive white Gaussian noise (AWGN) channel and the Rayleigh fading channel. Optimal soft decoding for the proposed JSCC scheme is studied. The soft decoder is based on the a posteriori probability (APP) algorithm for TCCPM with ring convolutional codes. It is shown that these systems with soft decoding outperform the same systems with hard decoding especially when the systems operate at low to medium signal-to-noise ratio (SNR). It is demonstrated that the new trellis quantisation schemes based on ring convolutional codes is superior to conventional trellis-coded quantisation (TCQ) of the same complexity. The novelty of this work is in the development of a trellis-based quantisation method using ring convolutional codes and the use of a soft decoder and the APP algorithm for the combined systems. Copyright (C) 2008 John Wiley & Sons, Ltd.

关键词： Critical path method Quantization signal to noise ratios Annulus Rayleigh fading convolutional coding Ring device Trellis codes rings group system combined source-channel coding

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Optimal soft decoding for combined trellis-coded quantization/modulation

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IEEE TRANSACTIONS ON COMMUNICATIONS 2000年第6期48卷 901-904页

作者： Ho, KP Chei, KH Chinese Univ Hong Kong Dept Informat Engn Shatin Hong Kong Peoples R China

The maximum a posteriori (MAP) algorithm is used as a minimum mean-squared-error decoder for combined trellis-coded quantization and modulation. The optimal trellis-coded quantizer is derived when the soft-decoding MAP algorithm is used as a decoder. The trellis-coded quantizer and the soft decoder are optimized iteratively for minimum overall distortion from transmitter input to receiver output. Significant performance improvement is achieved for both memoryless Gaussian and uniform source, especially for very noisy channels.

关键词： combined source-channel coding soft-decoding trellis-coded modulation trellis-coded quantization

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combined vector quantisation and index assignment with embedded redundancy for noisy channels

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ELECTRONICS LETTERS 2000年第20期36卷 1711-1713页

作者： Bozantzis, V Ali, FH Univ Sussex Sch Engn Brighton BN1 9QT E Sussex England

A new index assignment for Vector quantisation with embedded redundancy is introduced. The combined vector quantisation and index assignment with embedded redundancy technique provides an efficient vector encoder, performing both the functions of source and channel coding. It is shown that it is superior to channel-optimised Vector quantisation in terms of overall distortion and complexity.

关键词： embedded redundancy overall distortion vector quantisation channel coding redundancy Codes vector encoder complexity noisy channels combined source-channel coding index assignment

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combined source Adaptive and channel Optimized Matrix Quantization Algorithm

Combined Source Adaptive and Channel Optimized Matrix Quanti...

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5th International Conference on Information, Intelligence, Systems and Applications (IISA)

作者： Bozantzis, Vasilios Philippopoulos, Panos TEI Peloponnesus Sch Appl Technol Dept Comp Engn Sparti Greece

ISBN: (纸本)9781479961726

Matrix Quantization (MQ), a very promising source coding technique, has already been successfully applied for speech signals and noiseless channels. MQ is also shown in the literature to outperform Vector Quantization (VQ) when applied over noisy channels. Considering that most sources of practical interest are non-stationary, this paper introduces a technique which adapts MQ to varying source statistics and optimizes MQ for noisy channels, thus designs a matrix quantizer/decoder that considers both non-stationary source and noisy channel statistics. The resulting algorithm, combined source Adaptive and channel Optimized Matrix Quantization (CSACOMQ) is evaluated for a source modelled as the non-stationary Wiener process and over the memoryless Binary Symmetric channel (BSC). It is shown that CSACOMQ offers substantial Signal-to-Noise Ratio (SNR) performance improvement compared to the channel Optimized Matrix Quantization (COMQ).

关键词： Matrix Quantization channel Optimization Adaptive source coding combined source-channel coding

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Performance analysis and optimisation for edge connection of JSCC system based on double protograph LDPC codes

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IET COMMUNICATIONS 2018年第2期12卷 214-219页

作者： Hong, Shaohua Chen, Qiwang Wang, Lin Xiamen Univ Dept Commun Engn Xiamen 361005 Fujian Peoples R China

For a joint source-channel coding system based on double protograph low-density parity-check codes, the exchange of extrinsic information through edge connection between the source code and channel code is essential for good performance. In this study, the relationship between the performance and edge connection in the tanner graph is analysed and it has never been seen in the literature to the authors' knowledge. Both the joint protograph extrinsic information transfer and simulation results indicate that the edge connection should be optimised in practical applications since it plays an important role in the bit error rate performance and an optimisation scheme for the edge connection is put forward to enhance performance.

关键词： combined source-channel coding parity check codes optimisation edge connection JSCC system double protograph LDPC codes joint source-channel coding system double protograph low-density parity-check codes tanner graph joint protograph extrinsic information transfer bit error rate performance optimisation scheme

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On channel-constrained vector quantization and index assignment for discrete memoryless channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 1999年第7期45卷 2615-2622页

作者： Skoglund, M Royal Inst Technol Dept Signals Sensors & Syst SE-10044 Stockholm Sweden

This correspondence introduces an approach to the design of channel robust vector quantizers. Design criteria are derived based ion a new expression for the channel distortion as a function of the codevectors of the quantizer. The introduced framework for design and analysis holds for arbitrary discrete memoryless channels. Simulations demonstrate good performance. The correspondence also presents new results regarding the channel distortion as a function of the index assignment given to the codevectors of a vector quantizer.

关键词： channel distortion channel robust source coding combined source-channel coding discrete memoryless channel Hadamard transform index assignment vector quantization

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A UNIFIED APPROACH TO TREE-STRUCTURED AND MULTISTAGE VECTOR QUANTIZATION FOR NOISY channelS

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IEEE TRANSACTIONS ON INFORMATION THEORY 1993年第3期39卷 835-850页

作者： PHAMDO, N FARVARDIN, N MORIYA, T UNIV MARYLAND INST SYST RES College Pk MD 20742 USA NIPPON TELEGRAPH & TEL PUBL CORP MUSASHINO ELECT COMMUN LAB HUMAN INTERFACE LABS MUSASHINO TOKYO 180 JAPAN

Vector quantization (VQ) is a powerful and effective scheme that is widely used in speech and image coding applications. Two basic problems can be associated with VQ: (1) its large encoding complexity, and (2) its sensitivity to channel errors. These two problems have been independently studied in the past. These two problems are examined jointly. Specifically, the performances of two low-complexity VQ's-the tree-structured VQ (TSVQ) and the multistage VQ (MSVQ)-when used over noisy channels are analyzed. An algorithm is developed for the design of channel-matched TSVQ (CM-TSVQ) and channel-matched MSVQ (CM-MSVQ) under the squared-error criterion. Extensive numerical results are given for the memoryless Gaussian source and the Gauss-Markov source with correlation coefficient 0.9. Comparisons with the ordinary TSVQ and MSVQ designed for the noiseless channel show substantial improvements when the channel is very noisy. The CM-MSVQ, which can be regarded as a block-structured combined source-channel coding scheme, is then compared with a block-structured tandem source-channel coding scheme (with the same block length as the CM-MSVQ). For the Gauss-Markov source, the CM-MSVQ outperforms the tandem scheme in all cases that the authors have considered. Furthermore, it is demonstrated that the CM-MSVQ is fairly robust to channel mismatch.

关键词： TREE-STRUCTURED VECTOR QUANTIZATION MULTISTAGE VECTOR QUANTIZATION combined source-channel coding

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