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Rateless coding for Arbitrary Channel Mixtures With Decoder Channel State Information

IEEE TRANSACTIONS ON INFORMATION THEORY 2009年第9期55卷 4119-4133页

作者： Draper, Stark C. Kschischang, Frank R. Frey, Brendan Univ Wisconsin Dept Elect & Comp Engn Madison WI 53706 USA Univ Toronto Dept Elect & Comp Engn Toronto ON M5S 3G4 Canada

Rateless coding has recently been the focus of much practical as well as theoretical research. In this paper, rateless codes are shown to find a natural application in channels where the channel law varies unpredictably. Such unpredictability means that to ensure reliable communication block codes are limited by worst case channel variations. However, the dynamic decoding nature of rateless codes allows them to adapt opportunistically to channel variations. If the channel state selector is not malicious, but also not predictable, decoding can occur earlier, producing a rate of communication that can be much higher than the worst case. The application of rateless or "fountain" codes to the binary erasure channel (BEC) can be understood as an application of these ideas. Further, this sort of decoding can be usefully understood as an incremental form of erasure decoding. The use of ideas of erasure decoding result in a significant increase in reliability.

关键词： Arbitrarily varying channels channel coding erasure decoding error exponents individual sequence rateless codes variable-length coding

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Joint Source-Channel coding With Feedback

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IEEE TRANSACTIONS ON INFORMATION THEORY 2017年第6期63卷 3502-3515页

作者： Kostina, Victoria Polyanskiy, Yury Verdu, Sergio CALTECH Pasadena CA 91125 USA MIT 77 Massachusetts Ave Cambridge MA 02139 USA Princeton Univ Princeton NJ 08544 USA

This paper quantifies the fundamental limits of variable-length transmission of a general (possibly analog) source over a memoryless channel with noiseless feedback, under a distortion constraint. We consider excess distortion, average distortion, and guaranteed distortion (d-semifaithful codes). In contrast to the asymptotic fundamental limit, a general conclusion is that allowing variable-length codes and feedback leads to a sizable improvement in the fundamental delay-distortion tradeoff. In addition, we investigate the minimum energy required to reproduce k source samples with a given fidelity after transmission over a memoryless Gaussian channel, and we show that the required minimum energy is reduced with feedback and an average (rather than maximal) power constraint.

关键词： variable-length coding joint source-channel coding lossy compression single-shot method finite-blocklength regime rate-distortion theory feedback memoryless channels energy-distortion tradeoff

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Robust video transmission using block-interleaved error-resilient entropy coding

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OPTICAL ENGINEERING 2007年第12期46卷 127401-1-127401-7页

作者： Fang, Yong Jeong, Jechang Wu, Chenglke Yu, Lu Hanyang Univ Coll Engn Lab Image Commun & Signal Proc Dept Elect & Commun Engn Seoul 133791 South Korea Xidian Univ Natl Key Lab ISN Xian Peoples R China Zhejiang Univ Inst Informat & Commun Engn Hangzhou 310027 Peoples R China

variable-length coding (VLC) is widely used in video coding to improve compression efficiency. However, suffering from loss of synchronization, the VLC bit stream is much more sensitive to random errors than a fixed-length coding (FLC) bit stream. Error-resilient entropy coding (EREC) is a valid tool combating random errors in a VLC bit stream. Due to its intrinsic property of error propagation, when EREC is applied to a video bit stream, those blocks placed later become much more likely to be lost. We propose a simple method to further improve the error robustness of a video bit stream by interleaving transform coefficients of blocks so that low-frequency information is always placed ahead of high-frequency information. Thus, low-frequency information of greater significance is less likely to be lost. Experimental results prove the superiority of the proposed method. In addition, block interleaving can also be used in a data-partitioned video bit stream with ease. (C) 2007 Society of Photo-Optical Instrumentation Engineers.

关键词： video transmission error resilience block interleaving variable-length coding

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Queue-Aware Finite-Blocklength coding for Ultra-Reliable and Low-Latency Communications: A Cross-Layer Approach

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2022年第10期21卷 8786-8802页

作者： Zhao, Xiaoyu Chen, Wei Poor, H. Vincent Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China Chinese Univ Hong Kong Dept Informat Engn Hong Kong Peoples R China Tsinghua Univ Beijing Natl Res Ctr Informat Sci & Technol Beijing 100084 Peoples R China Princeton Univ Dept Elect & Comp Engn Princeton NJ 08544 USA

To provide reliable transmissions with low-latency requirements, we focus on Finite-Blocklength coding (FBC) in Ultra-Reliable and Low-Latency Communications (URLLC). However, ensuring the reliability and latency of FBC has remained an open issue in URLLC. In this paper, we develop a queue-aware FBC scheme under random arrivals. With the awareness of queue length, we employ variable-length coding to jointly encode packets, through which we obtain a benefit on reliability. Meanwhile, we optimize latency under a cross-layer approach, in which two classes of variable-length codes are investigated with resources allocated in the frequency and time domains, respectively. To obtain an optimal reliability-latency tradeoff under variable-length FBC, we first present the reliability and latency performance for single links based on a Constrained Markov Decision Process (CMDP). Providing reliability with a power allocation, we then obtain the optimal tradeoff by a Linear Programming (LP) problem, in which the probability of violation of the constraints on queue length and the number of transmitted packets is minimized under average constraints on resources. Moreover, we show an optimal threshold-based policy under Bernoulli arrivals. We finally consider some extensions of the optimal tradeoff for multi-user downlinks as well as single links with retransmission.

关键词： Reliability Encoding Delays Ultra reliable low latency communication Bandwidth Quality of service Power control Ultra-reliable and low-latency communications finite-blocklength coding cross-layer design variable-length coding optimal tradeoff between reliability and latency

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BINARY PREFIX CODES ENDING IN A 1

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IEEE TRANSACTIONS ON INFORMATION THEORY 1994年第4期40卷 1296-1302页

作者： CAPOCELLI, RM DESANTIS, A PERSIANO, G UNIV SALERNO DIPARTIMENTO INFORMAT & APPLICAZI-84081 BARONISSIITALY UNIV ROMA LA SAPIENZA DEPT COMP SCII-00185 ROMEITALY IBM CORP THOMAS J WATSON RES CTRYORKTOWN HTSNY 10598 HARVARD UNIV AIKEN COMPUTAT LABCAMBRIDGEMA 02138

Binary prefix codes with the constraint that each codeword must end with a ''1'' have been recently introduced by Berger and Yeung. We analyze the performance of such codes by investigating their average codeword length. In particular, we show that a very simple strategy permits the construction of a ''1''-ended binary prefix code whose average codeword length is less than H + 1 for any discrete source with entropy H. We also prove a tight lower bound on the optimal average codeword length in terms of H and of the minimum letter probability of the source. Finally, we discuss the problem of finding an optimum feasible code.

关键词： 1-ENDED CODES variable-length coding OPTIMAL CODES REDUNDANCY UPPER AND LOWER BOUNDS SEARCH METHODS

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Opportunistic Capacity and Error Exponent Region for the Compound Channel With Feedback

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IEEE TRANSACTIONS ON INFORMATION THEORY 2012年第7期58卷 4331-4341页

作者： Mahajan, Aditya Tatikonda, Sekhar Yale Univ Dept Elect Engn New Haven CT 06520 USA

variable length communication over a compound channel with feedback is considered. Traditionally, capacity of a compound channel without feedback is defined as the maximum rate that is determined before the start of communication such that communication is reliable. This traditional definition is pessimistic. In the presence of feedback, an opportunistic definition is given. Capacity is defined as the maximum rate that is determined at the end of communication such that communication is reliable. Thus, the transmission rate can adapt to the realized channel. Under this definition, feedback communication over a compound channel is conceptually similar to multiterminal communication. Transmission rate is a vector rather than a scalar;channel capacity is a region rather than a scalar;error exponent is a region rather than a scalar. In this paper, variable length communication over a compound channel with feedback is formulated, its opportunistic capacity region is characterized, and lower bounds for its error exponent region are provided.

关键词： Burnashev exponent error exponent region (EER) feedback error exponent variable-length coding variable-rate coding

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Multi-Hop Network With Multiple Decision Centers Under Expected-Rate Constraints

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IEEE TRANSACTIONS ON INFORMATION THEORY 2023年第7期69卷 4255-4283页

作者： Hamad, Mustapha Wigger, Michele Sarkiss, Mireille Inst Polytech Paris LTCI Telecom Paris F-91120 Palaiseau France Paris Res Ctr Huawei Math & Algorithm Sci Lab F-92100 Boulogne Billancourt France Inst Polytech Paris SAMOVAR Telecom Sud Paris F-91120 Palaiseau France

We consider a multi-hop distributed hypothesis testing problem with multiple decision centers (DCs) for testing against independence and where the observations obey some Markov chain. For this system, we characterize the fundamental type-II error exponents region, i.e., the type-II error exponents that the various DCs can achieve simultaneously, under expected rate constraints. Our results show that this fundamental exponents region is boosted compared to the region under maximum rate constraints, and that it depends on the permissible type-I error probabilities. When all DCs have equal permissible type-I error probabilities, the exponents region is rectangular and all DCs can simultaneously achieve their optimal type-II error exponents. When the DCs have different permissible type-I error probabilities, a tradeoff between the type-II error exponents at the different DCs arises. New achievability and converse proofs are presented. For the achievability, a new multiplexing and rate-sharing strategy is proposed. The converse proof is based on applying different change of measure arguments in parallel and on proving asymptotic Markov chains. For the special cases K is an element of {2, 3}, and for arbitrary K >= 2 when all permissible type-I error probabilities at the various DCs are equal, we provide simplified expressions for the exponents region;a similar simplification is conjectured for the general case.

关键词： Multi-hop distributed hypothesis testing error exponents expected-rate constraints variable-length coding

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variable-RATE TREE-STRUCTURED VECTOR QUANTIZERS

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IEEE TRANSACTIONS ON INFORMATION THEORY 1995年第4期41卷 917-930页

作者： BALAKRISHNAN, M PEARLMAN, WA LU, LG RENSSELAER POLYTECH INST DEPT ELECT COMP & SYST ENGNTROYNY 12180

In general, growth algorithms for optimal tree-structured vector quantizers do not exist. In this paper we show that if the source satisfies certain conditions;namely, that of diminishing marginal returns;optimal growth algorithms do exist. We present such an algorithm and compare its performance with that of other tree growth algorithms. Even for sources that do not meet the necessary conditions for the growth algorithm to be optimal, such as for speech with unknown statistics, it is seen by simulation that the algorithm outperforms other known growth algorithms. For sources that do not satisfy the required conditions, the algorithm presented here can also be used to grow the initial tree for the pruning process. The performance of Such pruned trees is superior to that of trees pruned from full trees of the same rate.

关键词： VECTOR QUANTIZATION TREE coding variable-RATE coding variable-length coding

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Optimal binary one-ended codes

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IEEE TRANSACTIONS ON INFORMATION THEORY 2002年第7期48卷 2125-2132页

作者： Kukorelly, Z Univ Calif San Diego Informat Coding Lab La Jolla CA 92093 USA

Binary prefix-free codes in which all codewords end with a "1" have been introduced by Berger and Yeung. A recursive method is given here for the construction of all optimal "1"-ended codes with n codewords. It is shown that the set of codes obtained by the construction contains only optimal codes. We also compute recursively the number of essentially different optimal "1"-ended codes with n codewords and show that their number grows faster than any polynomial in n.

关键词： one-ended codes optimal codes prefix-free codes variable-length coding

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High performance data compression method with pattern matching for biomedical ECG and arterial pulse waveforms

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COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2004年第1期74卷 11-27页

作者： Chen, WS Hsieh, L Yuan, SY Hsiuping Inst Technol Dept Informat Management Taichung Taiwan Natl Chi Nan Univ Dept Elect Engn VIPCC Lab Nantou Taiwan

Biomedical waveforms, such as electrocardiogram (ECG) and arterial pulse, always possess a lot of important clinical information in medicine and are usually recorded in a long period of time in the application of telemedicine. Due to the huge to compress the biomedical waveform data is vital. By recognizing the strong similarity and correlation between successive beat patterns in biomedical , waveform sequences, an efficient data compression scheme mainly based on pattern matching is introduced in this paper. The waveform codec consists mainly of four units: beat segmentation, beat normalization, two-stage pattern matching and template updating and residual beat coding. Three different residual beat coding Huffman/ run-length coding in discrete such as Huffman/ run-length coding methods, cosine transform domain, and vector quantization, are employed. The simulation results show that our compression algorithms achieve a very significant improvement in the performances of compression ratio and error measurement for both ECG and pulse, as compared with some other compression methods. (C) 2003 Elsevier Ireland Ltd. All rights reserved.

关键词： ECG arterial pulse waveform data compression variable-length coding discrete cosine transform vector quantization

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