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Multiple-Description coding by Dithered Delta-Sigma Quantization

IEEE TRANSACTIONS ON INFORMATION THEORY 2009年第10期55卷 4661-4675页

作者： Ostergaard, Jan Zamir, Ram Aalborg Univ Dept Elect Syst Aalborg Denmark Tel Aviv Univ Dept Elect Engn Syst IL-69978 Tel Aviv Israel

We address the connection between the multiple-description (MD) problem and Delta-Sigma quantization. The inherent redundancy due to oversampling in Delta-Sigma quantization, and the simple linear-additive noise model resulting from dithered lattice quantization, allow us to construct a symmetric and time-invariant MD coding scheme. We show that the use of a noise-shaping filter makes it possible to trade off central distortion for side distortion. Asymptotically, as the dimension of the lattice vector quantizer and order of the noise-shaping filter approach infinity, the entropy rate of the dithered Delta-Sigma quantization scheme approaches the symmetric two-channel MD rate-distortion function for a memoryless Gaussian source and mean square error (MSE) fidelity criterion, at any side-to-central distortion ratio and any resolution. In the optimal scheme, the infinite-order noise-shaping filter must be minimum phase and have a piecewise flat power spectrum with a single jump discontinuity. An important advantage of the proposed design is that it is symmetric in rate and distortion by construction, so the coding rates of the descriptions are identical and there is therefore no need for source splitting.

关键词： Delta-Sigma modulation dithered lattice quantization entropy coding joint source-channel coding multiple-description (MD) coding vector quantization

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Packet-by-packet adaptive scheme for video coding and transmission over wireless IP networks using rate-compatible punctured turbo (RCPT) codes

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WIRELESS PERSONAL COMMUNICATIONS 2007年第4期43卷 1675-1687页

作者： Pei, Yong Arnbetkar, Viraj S. Wright State Univ Dept Comp Sci & Engn Dayton OH 45435 USA

In this paper, we consider real-time video coding and transmission over packet-switched wireless IP networks, such as WLAN, using RCPT codes and joint source-channel coding (JSCC) with concentration on a packet-by-packet adaptive scheme. We present a systematic design methodology to enable the applicability of JSCC techniques. The performance of H.263+ video coding and transmission over wireless channel modeled as slow Rician fading channels using this approach is studied. Results indicate that a packet-by-packet adaptive RCPT-JSCC approach is of significant advantage for real-time video applications and leads to more acceptable video delivery quality over interference-limited and time-varying wireless networks.

关键词： video transmission RTP-H.263+ RCPT codes joint source-channel coding Rician fading

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A Minimum Mean-Squared Error Relay for the Two-Way Relay channel with Network coding

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IEEE COMMUNICATIONS LETTERS 2009年第3期13卷 196-198页

作者： Park, Moonseo Kim, Seong-Lyun Ajou Univ Div Elect & Comp Engn Commun Syst Lab Suwon 443749 South Korea Yonsei Univ Sch Elect & Elect Engn Radio Resource Management & Optimizat Lab Seoul 120749 South Korea

In this letter, we consider the two-way relay channel (TWRC) employing network coding. In TWRC, a conventional relay first decodes symbols from each user and combines (network coding) them using, for example, the XOR (eXclusive OR) operation. However, it may be suboptimal for the relay to use this concatenated approach, when the channels are noisy and the cost criterion is source distortion. Instead, we propose a new relay scheme that generates network coded symbols by performing symbol estimation and network coding operation jointly, in order to minimize the source distortion at the users.

关键词： joint source-channel coding minimum mean-squared error estimation network coding two-way relay channel

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Rate and power allocation for layered transmission with superposition coding

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IEEE SIGNAL PROCESSING LETTERS 2007年第11期14卷 773-776页

作者： Etemadi, Farzad Jafarkhani, Hamid Univ Calif Irvine Ctr Pervasive Communicat & Comp Dept Elect Engn & Comp Sci Irvine CA 92697 USA

We consider layered transmission of a Gaussian source over a quasi-static fading channel. A broadcast strategy is used in which multiple layers of source data are superimposed, and each layer is allocated a different power and transmission rate. For a multiple-antenna system where either the transmitter or the receiver has a single antenna, we propose a low-complexity algorithm for minimizing the expected end-to-end distortion of the received signal. Numerical results for a Rayleigh fading channel are presented, and the performance gain over a time-sharing strategy is quantified. It is numerically shown that for a wide range of operating conditions, equal rate allocation is as good as unequal rate allocation.

关键词： joint source-channel coding resource allocation superposition coding

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source and channel coding for Homogeneous Sensor Networks with Partial Cooperation

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第3期8卷 1113-1117页

作者： Simeone, O. New Jersey Inst Technol CWCSPR Newark NJ 07102 USA

A sensor networks in which two nodes communicate a remote measurement to an access point is investigated (CEO problem). The focus is on assessing the performance advantages of cooperative encoding strategies as enabled by out-of-band and finite-capacity communication links between the sensors. The analysis assumes Gaussian source and observation noises, a quadratic (MSE) distortion metric and homogeneous sensors. With rate-constrained links between each sensor and the access point, an achievable rate-distortion trade-off is derived that reduces to known rate-distortion characterizations in the cases without and with perfect cooperation. This result is then extended to a Gaussian multiple access channel scenario by deriving achievable distortions with separate or joint source-channel coding. It is concluded that, for both scenarios, even modest values of the capacity of the inter-sensor links enable the optimal performance with full sensor cooperation to be approached.

关键词： Wireless sensor networks CEO problem cooperative transmission joint source-channel coding

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On Robustness of Hybrid Digital Analog source-channel coding with Bandwidth Mismatch

On Robustness of Hybrid Digital Analog Source-Channel Coding...

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IEEE International Symposium on Information Theory (ISIT)

作者： Koeken, Erman Tuncel, Ertem Univ Calif Riverside Riverside CA 92521 USA

ISBN: (纸本)9781479951864

The problem of lossy transmission of a Gaussian source over an AWGN bandwidth-mismatched broadcast channel with three receivers is addressed. The tradeoff between the distortion levels at the good and the bad receivers is tackled when the distortion at the median receiver is required to be optimal. The problem was proposed by Tian and Shamai [8], who subsequently found in [9] remarkable achievability results for bandwidth expansion ratios k which are integers or unit fractions, i.e., k = 2, 1/3, 1/5, etc. Their result is extended here to all k >= 2 and k <= 1/2 by generalizing the hybrid digital/analog (HDA) scheme of [10] to the case of bandwidth mismatch. Finally, novel schemes are proposed for 1/2 <= k < 1 and 1 < k <= 2 achieving nontrivial tradeoffs.

关键词： Bandwidth mismatch hybrid digital/analog coding joint source-channel coding robustness

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Multi-layered video transmission over wireless channels using an adaptive modulation and coding scheme

Multi-layered video transmission over wireless channels usin...

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International Conference on Image Processing (ICIP 2001)

作者： Pei, Y Modestino, JW Rensselaer Polytech Inst Ctr Image Proc Res Elect Comp & Syst Engn Dept Troy NY 12180 USA

ISBN: (纸本)0780367251

In this paper we describe a multi-layered video transport scheme for wireless channels capable of adapting to channel conditions in order to maximize end-to-end quality of service (QoS). This scheme combines a scalable H.263+ video source coder with unequal error protection (UEP) ac-cross layers. The UEP is achieved by employing different channel codes together with a multiresolution modulation approach to transport the different priority layers. Adaptivity to channel conditions is provided through use of joint source-channel coding (JSCC) which attempts to jointly optimize the source and channel coding rates together with the modulation parameters to obtain the maximum achievable end-to-end QoS for the prevailing channel conditions. Results indicate that this adaptive JSCC scheme employing scalable video encoding together with a multiresolution modulation/coding approach leads to significant improvement-, in delivered video quality for specified channel conditions. In particular, the approach results in considerably improved graceful degradation properties for decreasing channel SNR.

关键词： video transport unequal error protection scalable video coding joint source-channel coding MPSK adaptive modulation and coding

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A generic dynamic FEC solution for video coding

A generic dynamic FEC solution for video coding

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15th IEEE International Symposium on Personal, Indoor, Mobile, Radio Communications (PIMRC 2004)

作者： Tavares, J Navarro, A Univ Aveiro Inst Telecommun P-3810 Aveiro Portugal

ISBN: (纸本)0780385233

In this paper, we present an adaptive scheme for forward error protection of any video coding standard. The channel coding rate changes according to the channel bit error rate (BER). The results are impressive. For instance, a PSNR gain of about 16.7 dB is obtained at BER=10(-2) for "Foreman" video sequence, encoded either by H.263 or by MPEG-I and protected using the Common scheme in comparison to the unprotected case. Being however this scheme common to all standards, it provides some acceptable video quality degradation. We have evaluated the quality degradation of the Common solution in comparison to the optimal scheme of protection, which uses a finite number of channel codes. Additionally, we propose a protection solution tailored to H.263/MPEG-4 video coding with an average PSNR improvement of about 0.2 dB relatively to the above mentioned Common solution.

关键词： wireless video video common protection joint source-channel coding MPEG-4 H.263

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Remote source coding Under Gaussian Noise: Dueling Roles of Power and Entropy Power

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IEEE TRANSACTIONS ON INFORMATION THEORY 2019年第7期65卷 4486-4498页

作者： Eswaran, Krishnan Gastpar, Michael Univ Calif Berkeley Dept Elect Engn & Comp Sci Berkeley CA 94720 USA Google Inc Hlth Res Team Mountain View CA 94043 USA Ecole Polytech Fed Lausanne Sch Comp & Commun Sci CH-1015 Lausanne Switzerland

The distributed remote source coding (the so-called CEO) problem is studied in the case where the underlying source, not necessarily Gaussian, has finite differential entropy and the observation noise is Gaussian. The main result is a new lower bound for the sum-rate-distortion function under arbitrary distortion measures. When specialized to the case of mean-squared error, it is shown that the bound exactly mirrors a corresponding upper bound, except that the upper bound has the source power (variance), whereas the lower bound has the source entropy power. Bounds exhibiting this pleasing duality of power and entropy power have been well known for direct and centralized source coding since Shannon's work. While the bounds hold generally, their value is most pronounced when interpreted as a function of the number of agents in the CEO problem.

关键词： source coding CEO problem entropy power entropy power inequality source-channel separation theorem joint source-channel coding rate loss

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Successive Segmentation-Based coding for Broadcasting Over Erasure channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 2016年第6期62卷 3026-3038页

作者： Tan, Louis Li, Yao Khisti, Ashish Soljanin, Emina Univ Toronto Dept Elect & Comp Engn Toronto ON M5S 3G4 Canada Akamai Technol Inc Santa Clara CA 95054 USA Rutgers State Univ Dept Elect & Comp Engn Piscataway NJ 08854 USA

Motivated by error correction coding in multimedia applications, we study the problem of broadcasting a single common source to multiple receivers over heterogeneous erasure channels. Each receiver is required to partially reconstruct the source sequence by decoding a certain fraction of the source symbols. We propose a coding scheme that requires only off-the-shelf erasure codes and can be easily adapted as users join and leave the network. Our scheme involves splitting the source sequence into multiple segments and applying a systematic erasure code to each such segment. We formulate the problem of minimizing the transmission latency at the server as a linear programming problem and explicitly characterize an optimal choice for the code rates and segment sizes. Through numerical comparisons, we demonstrate that our proposed scheme outperforms both separation-based coding schemes and degree-optimized rateless codes and performs close to a natural outer (lower) bound in certain cases. We further study individual user decoding delays for various orderings of segments in our scheme. We provide closed-form expressions for each individual user's excess latency when parity checks are successively transmitted in both increasing order and decreasing order of their segment's coded rate and also qualitatively discuss the merits of each order.

关键词： Application-layer error correction coding broadcast channels joint source-channel coding linear programming multimedia broadcast/multicast services (MBMS) rateless codes unequal error protection

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