检索结果-内蒙古大学图书馆

On Predictive coding for Erasure channels Using a Kalman Framework

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2009年第11期57卷 4456-4466页

作者： Arildsen, Thomas Murthi, Manohar N. Andersen, Soren Vang Jensen, Soren Holdt Aalborg Univ Dept Elect Syst DK-9220 Aalborg Denmark Univ Miami Coral Gables FL 33146 USA

We present a new design method for robust low-delay coding of autoregressive (AR) sources for transmission across erasure channels. It is a fundamental rethinking of existing concepts. It considers the encoder a mechanism that produces signal measurements from which the decoder estimates the original signal. The method is based on linear predictive coding and Kalman estimation at the decoder. We employ a novel encoder state-space representation with a linear quantization noise model. The encoder is represented by the Kalman measurement at the decoder. The presented method designs the encoder and decoder offline through an iterative algorithm based on closed-form minimization of the trace of the decoder state error covariance. The design method is shown to provide considerable performance gains, when the transmitted quantized prediction errors are subject to loss, in terms of signal-to-noise ratio (SNR) compared to the same coding framework optimized for no loss. The design method applies to stationary auto-regressive sources of any order. We demonstrate the method in a framework based on a generalized differential pulse code modulation (DPCM) encoder. The presented principles can be applied to more complicated coding systems that incorporate predictive coding as well.

关键词： Differential pulse code modulation (DPCM) erasure channels joint source-channel coding Kalman filtering linear predictive coding quantization

来源：评论

学校读者我要写书评

暂无评论

coding and Common Reconstruction

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2009年第11期55卷 4995-5010页

作者： Steinberg, Yossef Technion Israel Inst Technol Dept Elect Engn IL-32000 Technion Haifa Israel

This work studies problems of source and joint source-channel coding under the requirement that the encoder can produce an exact copy of the compressed source constructed by the decoder. This requirement, termed here as the common reconstruction constraint (CR), is satisfied automatically in rate-distortion theory for single sources. However, in the common formulation of problems of lossy source coding with side information at the decoder (the Wyner-Ziv problem), distributed source coding, and joint source-channel coding for networks, the destination can exploit the information it receives in a manner that cannot be exactly reproduced at the sender side. Some applications, like the transmission of sensitive medical information, may require that both sides-the sender and the receiver-will share a common version of the compressed data, for the purpose of future discussions or consulting. The purpose of this work is to study the implications of CR constraints on the achievable rates in scenarios of lossy source coding and lossy transmission of sources. Three problems are examined: source coding with side information at the decoder, simultaneous transmission of data and state over state-dependent channels, and joint source-channel coding for the degraded broadcast channel. Single-letter characterizations of the optimal performance are developed for these problems, under corresponding CR constraints. Implications of this constraint on problems of joint source-channel coding in networks are discussed.

关键词： Broadcast channel common reconstruction (CR) Gel'fand-Pinsker channel hierarchical coding joint source-channel coding source coding with side information successive refinement state-dependent channels Wyner-Ziv problem

来源：评论

学校读者我要写书评

暂无评论

Multiple-Description coding by Dithered Delta-Sigma Quantization

引用

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

来源：评论

学校读者我要写书评

暂无评论

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

引用

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

来源：评论

学校读者我要写书评

暂无评论

source and channel coding for Homogeneous Sensor Networks with Partial Cooperation

引用

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

来源：评论

学校读者我要写书评

暂无评论

Adaptive Mode- and Diversity-Control for Video Transmission on MIMO Wireless channels

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2009年第9期57卷 3624-3637页

作者： Hormis, Raju Linzer, Elliot Wang, Xiaodong Analog Devices Inc High Speed Signal Proc Grp Somerset NJ 08873 USA Ambarella Sunnyvale CA 94089 USA Columbia Univ Dept Elect Engn New York NY 10027 USA

Video transmitted over wireless channels incurs both encoder-induced distortion and distortion caused by transmission errors. To address these problems, we propose a framework to transmit video reliably over a Rayleigh-fading wireless channel employing multiple transmit and receive antennas. Although the formulation makes no assumptions about specific video-coding standards, it does presuppose some variation of motion-compensated block-transform coding. The scheme proposed here minimizes cumulative distortion over a window spanning multiple video units, and does so by adaptively controlling the diversity-and multiplexing-gain of the multiple-input multiple-output (MIMO) system. Crucially, this is done jointly with loss-aware rate-distortion optimization (LA-RDO) techniques at the video encoder. It turns out that MIMO and LA-RDO techniques, working in tandem, are more effective in minimizing distortion. The framework also ensures that delay and buffer constraints are satisfied for real-time transport. Numerical results with H.264-coded video show that adaptive MIMO and LA-RDO control yield tangible benefits (PSNR improvement), but only up to a point. Beyond this, real-time and buffer constraints limit what can be gained, even when the number of antennas is increased. In terms of solution approach, we show that the problem can be modelled as a sequence of geometric programs. Each problem can be solved optimally by a class of convex techniques known as primal-dual algorithms.

关键词： Convex programming diversity-multiplexing tradeoff geometric programs H.264 joint source-channel coding MIMO systems rate-distortion video coding

来源：评论

学校读者我要写书评

暂无评论

UNEQUAL LOSS-PROTECTED MULTIPLE DESCRIPTION coding OF SCALABLE source STREAMS USING A PROGRESSIVE APPROACH

UNEQUAL LOSS-PROTECTED MULTIPLE DESCRIPTION CODING OF SCALAB...

引用

16th IEEE International Conference on Image Processing

作者： Ardestani, Majid R. Aminlou, Alireza Shirazi, Ali Asghar Beheshti Iran Univ Sci & Technol Dept Elect Engn Tehran Iran Univ Tehran Dept Elect & Comp Engn Tehran Iran

ISBN: (纸本)9781424456536

An analysis-based approach for unequal loss-protected multiple description coding (packetization) of the scalable (prioritized / progressive) source code streams is proposed. For a given number of packets (descriptions) of the known size, unequal loss-protected packetization leads to segment the scalable code stream, such that the source can be reconstructed with the maximum possible fidelity at the decoder side. Here, we find an analytical relation between optimal sizes of any two consecutive segments. This idea yields a low-complexity progressive solution with a performance close to that of local search [1], which has been approved as an efficient method to solve the segmentation problem. Simulation results are used to confirm the efficiency of the proposed method as compared with the local search algorithm.

关键词： Unequal loss-protected packetization multiple description coding scalable code stream joint source-channel coding

来源：评论

学校读者我要写书评

暂无评论

On source Transmission Over MIMO channels With Limited Feedback

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2009年第1期57卷 324-341页

作者： Kim, Tung T. Skoglund, Mikael Caire, Giuseppe Royal Inst Technol Sch Elect Engn Stockholm Sweden Royal Inst Technol Sch Elect Engn S-10044 Stockholm Sweden Royal Inst Technol ACCESS Linnaeus Ctr S-10044 Stockholm Sweden Univ So Calif Dept Elect Engn Los Angeles CA 90089 USA

The problem of source-channel coding over a multiple-antenna (MIMO) channel with quantized channel state information at the transmitter (CSIT) is considered. Upper bounds on the distortion exponents achieved with partial CSIT under a long-term power constraint are developed. It is shown that the distortion exponent with perfect CSIT grows unbounded as the ratio between the channel and source bandwidth increases, while the exponent achieved with any feedback link of fixed, finite resolution is bounded above by a polynomial of the product between the number of transmit and number of receive antennas. The resolution of the feedback link should grow with the bandwidth ratio to make the distortion exponent scale as fast as that in the perfect-CSIT case. We show that in order to achieve the optimal scaling the CSIT feedback resolution must grow logarithmically with the bandwidth ratio for MIMO channels, and faster than linear for the single-input single-output channel. The achievable distortion exponent of some hybrid schemes with heavily quantized feedback is also derived. The results demonstrate that dramatic performance improvement over the case of no CSIT can be achieved by combining simple schemes with a very coarse CSIT feedback.

关键词： Diversity-multiplexing tradeoff joint source-channel coding large-deviation analysis MIMO systems

来源：评论

学校读者我要写书评

暂无评论

Universal source Controlled channel Decoding with Nonsystematic Quick-Look-In Turbo Codes

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2009年第4期57卷 960-971页

作者： Shamir, Gil I. Xie, Kai ADC Telecomm Inc San Jose CA 95134 USA

Utilization of redundancy left in a channel coded sequence can improve channel decoding performance. Stronger improvement can usually be achieved with nonsystematic encoding. However, nonsystematic codes recently proposed for this problem are not robust to the statistical parameters governing a sequence and thus should not be used without prior knowledge of these parameters. In this work, decoders of nonsystematic quick-look-in turbo codes are adapted to extract and exploit redundancy left in coded data to improve channel decoding performance. Methods, based on universal compression and denoising, for extracting the governing statistical parameters for various source models are integrated into the channel decoder by also taking advantage of the code structure. Simulation results demonstrate significant performance gains over standard systematic codes that can be achieved with the new methods for a wide range of statistical models and governing parameters. In many cases, performance almost as good as that with perfect knowledge of the governing parameters is achievable.

关键词： joint source-channel coding quick-look-in turbo codes universal source controlled channel decoding

来源：评论

学校读者我要写书评

暂无评论

MAP Decoding for Multi-Antenna Systems with Non-Uniform sources: Exact Pairwise Error Probability and Applications

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2009年第1期57卷 242-254页

作者： Behnamfar, Firouz Alajaji, Fady Linder, Tamas Nortel Networks Ottawa ON K2H 8E9 Canada Queens Univ Dept Math & Stat Kingston ON K7L 3N6 Canada Queens Univ Dept Elect & Comp Engn Kingston ON K7L 3N6 Canada Hungarian Acad Sci Comp & Automat Res Inst H-1111 Budapest Hungary

We study the maximum a posteriori (MAP) decoding of memoryless non-uniform sources over multiple-antenna channels. Our model is general enough to include space-time coding, BLAST architectures, and single-transmit multi-receive antenna systems which employ any type of channel coding. We derive a closed-form expression for the codeword pairwise error probability (PEP) of general multi-antenna codes using moment generating function and Laplace transform arguments. We then consider space-time orthogonal block (STOB) coding and prove that, similar to the maximum likelihood (ML) decoding case, detection of symbols is decoupled in MAP decoding. We also derive the symbol PEP in closed-form for STOB codes. We apply these results in several scenarios. First, we design a binary antipodal signaling scheme which minimizes the system bit error rate (BER) under STOB coding. At a BER of 10(-6), this constellation has a channel signal-to-noise ratio (CSNR) gain of 4.7 dB over conventional BPSK signaling for a binary non-uniform source with p(0) (sic) P(0) = 0.9. We next design space-time linear dispersion (LD) codes which are optimized for the source distribution under the criterion of minimizing the union upper bound on the frame error rate (FER). Two codes are given here: one outperforms V-BLAST by 3.5 dB and Alamouti's code by 12.3 dB at an FER of 10(-2) for a binary source with p(0) = 0.9, and the other outperforms V-BLAST by 4.2 dB at an FER of 10(-3) for a uniform source. These codes also outperform the LD codes of [13] constructed under a different criteria. Finally, the problem of bit-to-signal mapping is studied. It is shown that for a binary source with p(0) = 0.9, 64-QAM signaling, and SER = 10(-3), a gain of 3.7 dB can be achieved using a better-than-Gray mapping. For a system with one transmit and two receive antennas that uses trellis coding with 16-QAM signaling, a 1.8 dB gain over quasi-Gray mapping and ML decoding is observed when MAP decoding is used for binary so

关键词： joint source-channel coding space-time coding MAP decoding pairwise error probability statistical redundancy convolutional codes trellis coding maximum-ratio combining multi-antenna fading channels diversity wireless communications

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：