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Multicarrier transmission peak-to-average power reduction using simple block code

ELECTRONICS LETTERS 1998年第10期34卷 953-954页

作者： Fragiacomo, S Matrakidis, C O'Reilly, JJ Univ London Univ Coll Dept Elect & Elect Engn London WC1E 7JE England

A simple added-bit block code suitable for transmission in multicarrier systems is presented. It is applied across the carriers and offers a reduction in peak-to-average power ratio, without significantly reducing ove... 详细信息

关键词： multicarrier transmission systems codes block code PAPR complexity efficiency frequency division multiplexing Telecommunication applications peak-to-average power reduction block codes

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THE FOURIER-TRANSFORM FOR ENUMERATING THE WEIGHTS OF A LINEAR block code

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ANNALES DES TELECOMMUNICATIONS-ANNALS OF TELECOMMUNICATIONS 1995年第9-10期50卷 743-751页

作者： TORTELIER, P France Télécom — cnetpab-rgf Issy-les-Moulineaux France

The problem of computing the weight distribution of a lineal block code is addressed in this paper through the use of the Fourier transforms of indicator functions of parts of a set. After deriving the necessary mathematical formalism, we show that it enables to simply prove again certain known formulas (concerning for instance the Krawtchouk polynomials) and besides to derive two results we believe to be new. First, a recursion formula on polynomials enables dit-ect computation of the weight enumerator of the code in terms of its parity-check matrix. Second, since this formula leads in any case to cumbersome calculations, we derive analytical formulas concerning average weight estimates, together with an estimate of their precision.

关键词： ERROR CORRECTING code block code LINEAR code WEIGHT FOURIER TRANSFORMATION

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Utilization of Distributed Computing in Exhaustive Search for Optimal block code 4

Utilization of Distributed Computing in Exhaustive Search fo...

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4th International Conference on Communication and Information Systems (ICCIS)

作者： Loahavilai, Phatham Suksompong, Prapun Charoenlarpnopparut, Chalie Thammasat Univ Sirindhorn Int Inst Technol Sch Informat Comp & Commun Technol Pathum Thani Thailand

ISBN: (纸本)9781728162973

This paper presents an implementation of distributed computing to search for the optimal block error control code (covering both linear and nonlinear codes) for binary symmetric channels. The optimality is determined by comparing the decoding error probabilities when maximum likelihood decoders are used under the assumption that the codewords are equally likely. Several pre-processing steps are proposed to reduce the size of the search space. The search gives distance distributions which correspond to closed-form expressions for the minimum decoding error probability. Distributed computing is utilized to further reduce the search time. The proposed implementation can be extended to an arbitrary number of cloud servers. The amount of time saved by the search space reduction and distributed computing is also demonstrated.

关键词： block code distributed computing exhaustive search optimal non-linear block code optimal search

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Reducing Multicarrier Transmission Peak Power With A Modified Simple block code

Reducing Multicarrier Transmission Peak Power With A Modifie...

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2000 International Conference on Communication Technology(WCC2000·ICCT2000)

作者： Yunjun Zhang Abbas Yongacoglu Jean-Yves Chouinard School of Information Technology and Engineering University of OttawaOttawaOntarioK1N 6N5Canada

A modified version of the simple block code(SBC) presented in[1]is proposed to reduce the peak-to-average power ratio(PAPR) of multicarrier (such as Orthogonal Frequency Division Multiplexing) *** with the sub-block processing technique[2],the proposed scheme can effectively reduce the PAPR of multicarrier systems with large frame *** any given code rate R≥3/4,the maximum PAPR reduction that could be achieved by this kind of coding schemes is also derived.

关键词： OFDM Multicarrier system Peak-toaverage power ratio block code Peak power reduction

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Diagonal block space-time code design for diversity and coding advantage over flat fading channels

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2004年第4期52卷 1012-1020页

作者： Tao, MX Cheng, RS Hong Kong Appl Sci & Technol Res Inst Co Ltd Kowloon Hong Kong Peoples R China Hong Kong Univ Sci & Technol Dept Elect & Elect Engn Ctr Wireless Informat Technol Kowloon Hong Kong Peoples R China

The potential promised by multiple transmit antennas has raised considerable interest in space-time coding for wireless communications. In this paper, we propose a systematic approach for designing space-time trellis codes over flat fading channels with full antenna diversity and good coding advantage. It is suitable for an arbitrary number of transmit antennas with arbitrary signal constellations. The key to this approach is to separate the traditional space-time trellis code design into two parts. It first encodes the information symbols using a one-dimensional (M, 1) nonbinary block code, with M being the number of transmit antennas, and then transmits the coded symbols diagonally across the space-time grid. We show that regardless of channel time-selectivity, this new, class, of space-time codes always achieves a transmit diversity of order M with a minimum number of trellis states and a coding advantage equal to the minimum product distance of the employed block code. Traditional delay diversity codes can be viewed as a special case of this coding scheme in which the repetition block code is employed. To maximize the coding advantage, we introduce an optimal construction of the nonbinary block code for a given modulation scheme. In particular, an efficient suboptimal solution for multilevel phase-shift-keying (PSK) modulation is proposed Some code examples with 2-6 bits/s/Hz and two to six transmit antennas are provided, and they demonstrate excellent performance via computer simulations. Although it is proposed for flat fading channels, this coding scheme can be easily extended to frequency-selective fading channels.

关键词： block code delay diversity product distance space-time code transmit diversity

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ON STRUCTURAL COMPLEXITY OF THE L-SECTION MINIMAL TRELLIS DIAGRAMS FOR BINARY LINEAR block-codeS

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 1993年第9期E76A卷 1411-1421页

作者： KASAMI, T TAKATA, T FUJIWARA, T LIN, S Advanced Inst of Science and Technology Ikoma-shi Japan

A linear block code has a finite-length trellis diagram which terminates at the length of the code. Such a trellis diagram is expressed and constructed in terms of sections. The complexity of an L-section trellis diagram for a linear block code is measured by the state and branch complexities, the state connectivity, and the parallel structure. The state complexity is defined as the number of states at the end of each section of the L-section trellis diagram, the branch complexity is defined as the number of parallel branches between two adjacent states, the state connectivity is defined in terms of the number of states which are adjacent to and from a given state and the connections between disjoint subsets of states, and the parallel structure is expressed in terms of the number of parallel sub-trellis diagrams without cross connections between them. This paper investigates the branch complexity, the state connectivity, and the parallel structure of an L-section minimal trellis diagram for a binary linear block code. First these complexities and structure are expressed in terms of the dimensions of specific subcodes of the given code. Then, the complexities of 2-section minimal trellis diagrams for Reed-Muller codes are given.

关键词： LINEAR code block code TRELLIS DIAGRAM REED-MULLER code

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On the BCJR trellis for linear block codes

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IEEE TRANSACTIONS ON INFORMATION THEORY 1996年第4期42卷 1072-1092页

作者： McEliece, RJ Department of Electrical Engineering California Institute of Technology Pasadena CA USA

In this semi-tutorial paper, we will investigate the computational complexity of an abstract version of the Viterbi algorithm on a trellis, and show that if the trellis has e edges, the complexity of the Viterbi algortithm is Theta(e), This result suggests that the ''best'' trellis representation for a given linear block code is the one with the fewest edges, We will then show that, among all trellises that represent a given code, the original trellis introduced by BahI, Cocke, Jelinek, and Raviv in 1974, and later rediscovered by Wolf, Massey, and Forney, uniquely minimizes the edge count, as well as several other figures of merit. Following Forney and Kschischang and Sorokine, we will also discuss ''trellis-oriented'' or ''minimal-span'' generator matrices, which facilitate the calculation of the size of the BCJR trellis, as well as the actual construction of it.

关键词： block code trellis Viterbi algorithm decoding complexity

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A new identity concerning the weight enumerator of binary linear block codes

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ANNALES DES TELECOMMUNICATIONS-ANNALS OF TELECOMMUNICATIONS 2007年第9-10期62卷 1121-1142页

作者： Tortelier, Patrick France Telecom Div R&D F-92794 Issy Les Moulineaux France

Starting from the problem of counting the number of parity check equations of a given code that allow to recover an erasure from a pattern we derive a series of identities involving only the coefficients of the weight enumerator of the code, and thus different from MacWilliam's identities. These relations can also be gathered in a single polynomial equation, which is thought to be new and is the main result of this paper Some examples with known block codes are given.

关键词： error correcting code linear code block code enumeration weight erasure

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Multiple subcarrier modulation for infrared wireless systems using punctured convolutional codes and variable amplitude block codes

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IEICE TRANSACTIONS ON COMMUNICATIONS 2003年第8期E86B卷 2433-2439页

作者： Yamaguchi, H Ohtsuki, T Sasase, I Keio Univ Dept Informat & Comp Sci Yokohama Kanagawa 223 Japan Tokyo Univ Sci Dept Elect Engn Noda Chiba 2788510 Japan

In this paper, we propose multiple subcarrier modulation (MSM) for infrared wireless systems using punctured convolutional codes and variable amplitude block codes to minimize the average optical power by allocating the appropriate amplitudes to the puncturing bits. The proposed system maps the coded bits corresponding to zeros in the puncturing table to the amplitudes of subcarriers, while the rate-compatible punctured convolutional (RCPC) code deletes them. We compare two proposed systems with the conventional systems: one block code maps the coded bits corresponding to zeros in the puncturing table to zeros (proposed 1), and the other maps them to the appropriate values among 0, and +/-1 (proposed 2) so that the required bias can be minimized. We show that the proposed 2 can achieve the minimum required SNR at the same average optical power and the same information rate among all the systems.

关键词： indoor infrared wireless system MSM RCPC block code

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OPTIMUM SOFT-DECODING OF LINEAR block-codeS .2. ANALYSIS AND SIMULATION RESULTS

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ANNALS OF TELECOMMUNICATIONS 1986年第11-12期41卷 580-604页

作者： BATTAIL, G FANG, J 1.Département Systèmes et Communications Ecole nationale supérieure des télécommunications 46 rue Barrault 75634 Paris cedex 13

Les auteurs se proposent d’étudier la complexité d’un algorithme de décodage pondéré des codes linéaires en blocs précédemment publié et de certaines de ses variantes sim... 详细信息

Les auteurs se proposent d’étudier la complexité d’un algorithme de décodage pondéré des codes linéaires en blocs précédemment publié et de certaines de ses variantes simplifiées, en se restreignant au cas binaire. On présente à cet effet des calculs basés sur un modèle simplifié du fonctionnement du décodeur ainsi que des résultats de sa simulation. On commence par rappeler la description de cet algorithme en se référant au diagramme du treillis associé au code. Une description probabiliste du fonctionnement de l’algorithme sert d’introduction à un modèle dans lequel les ?cotes? associées à chaque chemin du treillis, qu’il s’agit de comparer, sont scindées en deux termes additifs, l’un certain, l’autre aléatoire. Une évaluation de la complexité de l’algorithme optimal et de certaines de ses variantes simplifiées est développée à partir de ce modèle. La méthode de simulation de l’algorithme et de ses variantes, ainsi que les résultats obtenus, sont enfin présentés.

关键词： code bloc code linéaire Décodage Algorithme optimal Pondération Simulation numérique Complexité algorithme code binaire Modèle stochastique block code Linear code Decoding Optimal algorithm Weighting Digital simulation Algorithm complexity Binary code Stochastic model

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