IEEE Transactions on Information Theory

Volume 46 Issue 4 • July 2000

Filter Results

Displaying Results 1 - 25 of 58
  • Contributors

    Publication Year: 2000, Page(s):1697 - 1708
    Request permission for commercial reuse | PDF file iconPDF (98 KB)
    Freely Available from IEEE
  • Nested input-constrained codes

    Publication Year: 2000, Page(s):1302 - 1316
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    An input-constrained channel, or simply a constraint, is a set S of words that is generated by a finite labeled directed graph. An encoder for S maps, in a lossless manner, sequences of unconstrained input blocks into sequences of channel blocks, the latter sequences being words of S. In most applications, the encoders are finite-state machines and, thus, presented by state diagrams. In the specia... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Finding the permutation between equivalent linear codes: the support splitting algorithm

    Publication Year: 2000, Page(s):1193 - 1203
    Cited by:  Papers (25)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (304 KB)

    Two linear codes are permutation-equivalent if they are equal up to a fixed permutation on the codeword coordinates. We present here an algorithm able to compute this permutation. It operates by determining a set of properties invariant by permutation, one for each coordinate, called a signature. If this signature is fully discriminant-i.e., different for all coordinates-the support of the code sp... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Two-dimensional weight-constrained codes through enumeration bounds

    Publication Year: 2000, Page(s):1292 - 1301
    Cited by:  Papers (17)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (352 KB)

    For a rational α∈(0,1), let 𝒜n×m,α be the set of binary n×m arrays in which each row has Hamming weight αm and each column has Hamming weight αn, where αm and αn are integers. (The special case of two-dimensional balanced arrays corresponds to α=1/2 and even values for n and m.) The redundancy of 𝒜n×m,&alpha... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bounds on the a priori index crossover probabilities for trellis-based channel codes

    Publication Year: 2000, Page(s):1276 - 1291
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (384 KB)

    This paper derives truncated union bounds on the a priori index crossover probabilities p(j|i) that result when an n-bit data index i is convolutionally encoded, transmitted over a noisy channel, and decoded with the Viterbi algorithm, giving received index j. The bounds are derived with a modified transfer function technique, using n-stage state transition matrices with symbolic labels. The techn... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The smallest length of eight-dimensional binary linear codes with prescribed minimum distance

    Publication Year: 2000, Page(s):1539 - 1544
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (192 KB)

    Let n(8,d) be the smallest integer n for which a binary linear code of length n, dimension 8, and minimum distance d exists. We prove that n(8,18)=42, n(8,26)=58, n(8,28)=61, n(8,30)=65, n(8,34)=74, n(8,36)=77, n(8,38)=81, n(8,42)=89, and n(8,60)=124. After these results, all values of n(8,d) are known View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A class of linear codes with good parameters from algebraic curves

    Publication Year: 2000, Page(s):1527 - 1532
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (264 KB)

    A class of linear codes with good parameters is constructed in this correspondence. It turns out that linear codes of this class are subcodes of the subfield subcodes of Goppa's geometry codes. In particular, we find 61 improvements on Brouwer's table based on our codes View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • New ternary quasi-cyclic codes with better minimum distances

    Publication Year: 2000, Page(s):1554 - 1558
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (176 KB)

    One of the most important problems of coding theory is to construct codes with best possible minimum distances. In this article, using the structure of quasi-cyclic (QC) codes with a BCH-type bound given by Lally and Fitzpatrick (see WCC '99, Workshop on Coding and Cryptography, Paris, France, 1999), we have found 20 new ternary quasi-cyclic codes with improved minimum distances View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Matrices with banded inverses: inversion algorithms and factorization of Gauss-Markov processes

    Publication Year: 2000, Page(s):1495 - 1509
    Cited by:  Papers (47)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (352 KB)

    The paper considers the inversion of full matrices whose inverses are L-banded. We derive a nested inversion algorithm for such matrices. Applied to a tridiagonal matrix, the algorithm provides its explicit inverse as an element-wise product (Hadamard product) of three matrices. When related to Gauss-Markov random processes (GMrp), this result provides a closed-form factored expression for the cov... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Duality theorems for joint source-channel coding

    Publication Year: 2000, Page(s):1263 - 1275
    Cited by:  Papers (6)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (392 KB)

    We consider joint source-channel coding for a memoryless Gaussian source and an additive white Gaussian noise (AWGN) channel. For a given code defined by an encoder-decoder pair (α, β), its dual code is obtained by interchanging the encoder and decoder: (β, α). It is shown that if a code (α, β) is optimal at rate p channel uses per source sample and if it satisfies... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Asymptotic performance analysis of Bayesian target recognition

    Publication Year: 2000, Page(s):1658 - 1665
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (440 KB)

    This article investigates the asymptotic performance of Bayesian target recognition algorithms using deformable-template representations. Rigid computer-aided design (CAD) models represent the underlying targets; low-dimensional matrix Lie-groups (rotation and translation) extend them to particular instances. Remote sensors observing the targets are modeled as projective transformations, convertin... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Chinese remaindering with errors

    Publication Year: 2000, Page(s):1330 - 1338
    Cited by:  Papers (55)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (240 KB)

    The Chinese remainder theorem states that a positive integer m is uniquely specified by its remainder module k relatively prime integers p 1, ···, pk, provided m<Πi=1kpi. Thus the residues of m module relatively prime integers p1<p2<···<pn form a redunda... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the minimum distances of Schubert codes

    Publication Year: 2000, Page(s):1535 - 1538
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (176 KB)

    Ghorpade and Lachaud (1998) introduced Schubert codes as codes corresponding to the protective system (Tsfasman and Vladut 1991) defined by Schubert subvarieties of Grassmann varieties Gr(l,m). They gave an upper bound for the minimum distances of these codes in Ghorpade and Lachaud and conjectured their true minimum distances. In this note we prove the conjecture in the case of l=2 View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A note on the discrete wavelet transform of second-order processes

    Publication Year: 2000, Page(s):1673 - 1676
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (184 KB)

    Some properties of second-order random processes such as, stationarity and scaling, are characterized via corresponding (multiscale) properties of their discrete wavelet transform. The single scale characterizations valid in the continuous setting do not extend to the discrete setting. Some extensions of these results are also indicated View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Authentication theory and hypothesis testing

    Publication Year: 2000, Page(s):1350 - 1356
    Cited by:  Papers (58)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (144 KB)

    By interpreting message authentication as a hypothesis testing problem, this paper provides a generalized treatment of information-theoretic lower bounds on an opponent's probability of cheating in one-way message authentication. We consider the authentication of an arbitrary sequence of messages, using the same secret key shared between sender and receiver. The adversary tries to deceive the rece... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Error exponents for maximum-likelihood and successive decoders for the Gaussian CDMA channel

    Publication Year: 2000, Page(s):1683 - 1691
    Cited by:  Papers (19)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (368 KB)

    Random-coding error exponents are derived for the Gaussian code-division multiple-access (CDMA) channel for the maximum-likelihood and optimum successive decoders. Error exponents not only specify the capacity region of the channel, which is known, but also give lower bounds on the rate of exponential decay of the average probability of error as a function of the block length of random codes. A co... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bounds on the state complexity of codes from the Hermitian function field and its subfields

    Publication Year: 2000, Page(s):1523 - 1527
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (224 KB)

    An upper bound on the minimal state complexity of codes from the Hermitian function field and some of its subfields is derived. Coordinate orderings under which the state complexity of the codes is not above the bound are specified. For the self-dual Hermitian code it is proved that the bound coincides with the minimal state complexity of the code. Finally, it is shown that Hermitian codes over fi... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A note on type II convolutional codes

    Publication Year: 2000, Page(s):1510 - 1514
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (152 KB)

    The result of a search for the world's second type II (doubly-even and self-dual) convolutional code is reported. A rate R=4/8, 16-state, time-invariant, convolutional code with free distance dfree=8 was found to be type II. The initial part of its weight spectrum is better than that of the Golay convolutional code (GCC). Generator matrices and path weight enumerators for some other typ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Guaranteed error correction rate for a simple concatenated coding scheme with single-trial decoding

    Publication Year: 2000, Page(s):1590 - 1597
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (272 KB)

    We consider a concatenated coding scheme using a single inner code, a single outer code, and a fixed single-trial decoding strategy that maximizes the number of errors guaranteed to be corrected in a concatenated codeword. For this scheme, we investigate whether maximizing the guaranteed error correction rate, i.e., the number of correctable errors per transmitted symbol, necessitates pushing the ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • There is no ternary [28, 6, 16] code

    Publication Year: 2000, Page(s):1550 - 1554
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (192 KB)

    The existence of a ternary [28, 6, 16] code is considered. We show that without loss of generality, a generator matrix of such a code must satisfy certain conditions. A computer search over all matrices that satisfy these conditions reveals that a ternary [28, 6, 16] code does not exist View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Near-optimal limited-search detection on ISI/CDMA channels and decoding of long convolutional codes

    Publication Year: 2000, Page(s):1459 - 1482
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (664 KB)

    We derive an upper bound on the bit-error probability (BEP) in limited-search detection over a finite interference channel. A unified channel model is presented; this includes finite-length intersymbol interference channels and multiuser CDMA channels as two special cases. We show that the BEP of the M-algorithm (MA) is bounded from above by the sum of three terms: an upper bound on the error prob... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A probabilistic approach to some asymptotics in noiseless communication

    Publication Year: 2000, Page(s):1246 - 1262
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (488 KB)

    Renewal theory is a powerful tool in the analysis of source codes. We use renewal theory to obtain some asymptotic properties of finite-state noiseless channels. We discuss the relationship between these results and earlier uses of renewal theory to analyze the Lempel-Ziv (1977, 1978) codes and the Tunstall (1967) code. As a new application of our results, we provide the asymptotic performance of ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On memory redundancy in the BCJR algorithm for nonrecursive shift register processes

    Publication Year: 2000, Page(s):1580 - 1584
    Cited by:  Papers (4)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (224 KB)

    For computation of a posteriori probabilities (APPs), the well-known Bahl, Cocke, Jelinek, and Raviv (1974) algorithm is often applied. If the underlying model is a nonrecursive shift register process, it is shown that this algorithm obtains a general memory redundancy if the computation is performed over a commutative semiring with an absorbing zero element. The result is of particular interest f... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Shannon-theoretic approach to a Gaussian cellular multiple-access channel with fading

    Publication Year: 2000, Page(s):1401 - 1425
    Cited by:  Papers (130)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (744 KB)

    Shannon-theoretic limits on the achievable throughput for a simple infinite cellular multiple-access channel (MAC) model (Wyner 1994) in the presence of fading are presented. In this model, which is modified to account for flat fading, the received signal, at a given cell-site's antenna, is the sum of the faded signals transmitted from all users within that cell plus an attenuation factor α&... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the training distortion of vector quantizers

    Publication Year: 2000, Page(s):1617 - 1623
    Cited by:  Papers (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (272 KB)

    The in-training-set performance of a vector quantizer as a function of its training set size is investigated. For squared error distortion and independent training data, worst case type upper bounds are derived on the minimum training distortion achieved by an empirically optimal quantizer. These bounds show that the training distortion can underestimate the minimum distortion of a truly optimal q... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

IEEE Transactions on Information Theory publishes papers concerned with the transmission, processing, and utilization of information.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Prakash Narayan 

Department of Electrical and Computer Engineering