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An efficient universal coding algorithm for noiseless channel with symbols of unequal cost

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1997年第11期E80A卷 2232-2237页

作者： Iwata, K Morii, M Uyematsu, T Department of Information Science and Intelligent Systems Faculty of Engineering University of Tokushima Tokushima-shi 770 Japan School of Information Science Japan Advanced Institute of Science and Technology Ishikawa Ishikawa-ken 923-12 Japan

This paper describes an effcient and simple coding algorithm of universally optimal codes for stationary (ergodic) sources and noiseless channel with unequal symbol costs. The symbol cost indicates the required time (or space) for the transmission (or storage) of that symbol, and the cost of any code symbol depends only on that symbol. The proposed coding algorithm mainly consists of two parts. The first part is based on the well-known Ziv-Lempel coding algorithm proposed in 1978 (sometimes called LZ78), and the second part is based on the Varn coding algorithm. The coding algorithm asymptotically achieves an optimal average cost of codes for stationary sources, and also achieves an optimal cost of codes for stationary ergodic sources with probability one. Furthermore, the computational complexity of the proposed coding algorithm is linear with respect to the length of source sequence and coded sequence.

关键词： noiseless coding additive cost of code symbol universally optimal cost coding Ziv-Lempel coding Varn coding

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Reversible arithmetic coding for quantum data compression

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IEEE TRANSACTIONS ON INFORMATION THEORY 2000年第3期46卷 1104-1116页

作者： Chuang, IL Modha, DS IBM Corp Almaden Res Ctr San Jose CA 95120 USA

We study the problem of compressing a block of symbols (a block quantum state) emitted by a memoryless quantum Bernoulli source. We present a simple-to-implement quantum algorithm for projecting, with high probability the block quantum state onto the typical subspace spanned by the leading eigenstates of its density matrix. We propose a fixed-rate quantum Shannon-Fano code to compress the projected block quantum state using a per-symbol code rate that is slightly higher than the von Neumann entropy limit. Finally, we propose quantum arithmetic codes to efficiently implement quantum Shannon-Fano codes. Our arithmetic encoder and decoder have a cubic circuit and a cubic computational complexity in the block size. Both the encoder and decoder are quantum-mechanical inverses of each other, and constitute an elegant example of reversible quantum computation.

关键词： arithmetic coding noiseless coding quantum communication quantum computation quantum information theory quantum measurement reversible computation Schumacher coding

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coding WITH DIGITS OF UNEQUAL COST

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IEEE TRANSACTIONS ON INFORMATION THEORY 1995年第2期41卷 596-600页

作者： GILBERT, EN AT&T Bell Lab Murray Hill NJ USA

At present, optimal coding for a noiseless digital channel with digits of unequal cost requires solving a large linear programming problem. Much simpler procedures give codes, resembling Shannon's and Huffman'... 详细信息

关键词： HUFFMAN CODE ZIPFS LAW TELEGRAPH noiseless coding ALGORITHMS

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The capacity of hybrid quantum memory

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IEEE TRANSACTIONS ON INFORMATION THEORY 2003年第6期49卷 1465-1473页

作者： Kuperberg, G Univ Calif Davis Dept Math Davis CA 95616 USA

The general stable quantum memory unit is a hybrid consisting of a classical digit with a quantum digit (qudit) assigned to each classical state. The shape of the memory is the vector of sizes of these qudits, Which may differ. We determine when N copies of a quantum memory A embed in N(1 + o(1)) copies of another quantum memory *** relationship captures the notion that B is as at least as useful as A for all purposes in the bulk limit. We show that the embeddings exist if and only if for all p greater than or equal to 1, the p-norm of the shape of A does not exceed the p-norm of the shape of B. The log of the p-norm of the shape of A can be interpreted as the maximum of S(rho) + H(rho)/rho (quantum entropy plus discounted classical entropy) taken over all mixed states p on A We also establish a noiseless coding theorem that justifies these entropies. The noiseless coding theorem and the bulk embedding theorem together say that either A blindly bulk-encodes into B with perfect fidelity, or A admits a state that does not visibly bulk-encode into B with high fidelity. In conclusion, the utility of a hybrid quantum memory is determined by its simultaneous capacity for classical and quantum entropy, which is not a finite list of numbers, but rather a convex region in the classical-quantum entropy plane.

关键词： channel capacity embedding entropy fidelity hybrid memory noiseless coding quantum

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Encoding and Decoding Schemes in Communication Systems using Orthogonal coding for Noise Immunity's Increase

Encoding and Decoding Schemes in Communication Systems using...

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Wave Electronics and its Application in Information and Telecommunication Systems (WECONF)

作者： Rabin, A., V St Petersburg State Univ Aerosp Instrumentat St Petersburg Russia

ISBN: (纸本)9781728122885

The objective of the paper is a development and a research of the offered by the author orthogonal coding as a way of noise immunity's increase using the example of the information communication systems with a phase-shift keying. It is shown, that the orthogonal coding allows to provide the required quality of communication with a smaller energy cost. The energy gain in signal-to-noise ratio is provided by more effective use of energy of transmitted signals with the fixed code rate, without increase in complexity and cost of transmitting/receiving schemes. The orthogonal coding is an analogue of convolutional coding over the rational numbers' field. Properties of orthogonality of proposed codes allow to strengthen significance of useful signal with simultaneous weakening of influence of AWGN. Technical realization of orthogonal coding is characterized by low complexity: on each step a decoding process is reduced to calculation of several dot products and comparison with the fixed (zero, in this case) threshold. For this reason, the offered way of coding and design of receiving and transmitting schemes can be implemented in various communication systems.

关键词： noiseless coding orthogonal coding phase-shift keying spectral efficiency encoding schemes decoding schemes

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Segmentation of Telemetry Frames During Message Packing in Wireless Sensor Networks

Segmentation of Telemetry Frames During Message Packing in W...

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IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (ElConRus)

作者： Samoylenko, Vladimir V. Sukmanov, Alexander V. Fedorenko, Vladimir V. Listova, Natalia V. Samoylenko, Irina V. Stavropol State Agrarian Univ Dept Electrotech Automat & Metrol Stavropol Russia DonSTU Inst Serv & Technol Branch Dept Informat Syst Technol & Commun Pyatigorsk Russia North Caucasus Fed Univ Dept Appl Math & Math Simulat Stavropol Russia

ISBN: (纸本)9781538643402

A model for evaluating wireless communication channel capacity with the noiseless coding of messages in the case of repeated transfer of damaged information packets is proposed. The optimum values of the information packet characteristics are calculated according to various ratios of the signal energy parameters and interference in the channels. An algorithm of telemetry frame segmentation into subframes is presented. The number of elements in the subframes is maximal approximated to the number of information elements in packets of optimal length. Here the multiplicity condition of telemetry frame length is considered in relation to the number of subframe elements. It is very important in a case of cyclic interrogation for measuring sensors.

关键词： Wireless Sensor Network Telemetry Frame noiseless coding Information Packet

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Method of Message coding, Using Ortogonal Chaotic Signals in Secure Information Telecommunication Networks 4

Method of Message Coding, Using Ortogonal Chaotic Signals in...

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4th International Scientific-Practical Conference Problems of Infocommunications. Science and Technology (PIC S&T)

作者： Vasuyta, Konstantin Zakharchenko, Irina Ivan Kozhedub Kharkov Natl Univ Air Force Kharkov Ukraine

The paper proposes a method of message coding using orthogonal chaotic signals obtained by a Modified Discrete Chaotic Map Based on Cheby shev Polynomial and the Gram-Schmidt orthogonalization procedure. The proposed ... 详细信息

ISBN: (纸本)9781538609835

关键词： signal-construction signal constellation chaotic sequence reliability Pearson correlation coefficient Gram-Schmidt orthogonalization noiseless coding

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Codes: Unequal Probabilities, Unequal Letter Cost

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Journal of the ACM (JACM) 1980年第3期27卷 412-427页

作者： Altenkamp, Doris Mehlhorn, Kurt University of Saarlandes Federal Republic of Germany 6600 66 Saarbrücken Fachbereich 10 Germany

The construction of alphabetic prefix codes with unequal letter costs and unequal probabilities is considered. A variant of the noiseless coding theorem is proved giving closely matching lower and upper bounds for the cost of the optimal code. An algorithm is described which constructs a nearly optimal code in linear time. © 1980, ACM. All rights reserved.

关键词： approximation algorithm codes noiseless coding prefix codes search trees unequal letter costs unequal probabilities

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