# IEEE Transactions on Information Theory

## Filter Results

Displaying Results 1 - 25 of 44

Publication Year: 2007, Page(s):C1 - C4
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• ### IEEE Transactions on Information Theory publication information

Publication Year: 2007, Page(s): C2
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• ### Associate Editors

Publication Year: 2007, Page(s): 1
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• ### 2006 Information Theory Society Paper Award

Publication Year: 2007, Page(s): 2
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• ### 2006 IEEE Communications Society and Information Theory Society Joint Paper Award

Publication Year: 2007, Page(s):3 - 4
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• ### On Designing Good LDPC Codes for Markov Channels

Publication Year: 2007, Page(s):5 - 21
Cited by:  Papers (23)
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This paper presents a reduced-complexity approximate density evolution (DE) scheme for low-density parity-check (LDPC) codes in channels with memory in the form of a hidden Markov chain. This approximation is used to design degree sequences representing some of the best known LDPC code ensembles for the Gilbert-Elliott channel, and example optimizations are also given for other Markov channels. Th... View full abstract»

• ### An MSE-Based Transfer Chart for Analyzing Iterative Decoding Schemes Using a Gaussian Approximation

Publication Year: 2007, Page(s):22 - 38
Cited by:  Papers (20)
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An alternative to extrinsic information transfer (EXIT) charts called mean-square error (MSE) charts that use a measure related to the MSE instead of mutual information is proposed. Using the relationship between mutual information and minimum mean-square error (MMSE) for the additive white Gaussian noise (AWGN) channel, a relationship between the rate of any code and the area under a plot of MMSE... View full abstract»

• ### Asymptotic Spectra of Trapping Sets in Regular and Irregular LDPC Code Ensembles

Publication Year: 2007, Page(s):39 - 55
Cited by:  Papers (61)
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We evaluate the asymptotic normalized average distributions of a class of combinatorial configurations in random, regular and irregular, binary low-density parity-check (LDPC) code ensembles. Among the configurations considered are trapping and stopping sets. These sets represent subsets of variable nodes in the Tanner graph of a code that play an important role in determining the height and point... View full abstract»

• ### Finite-Dimensional Bounds on ${\BBZ}_m$ and Binary LDPC Codes With Belief Propagation Decoders

Publication Year: 2007, Page(s):56 - 81
Cited by:  Papers (20)
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This paper focuses on finite-dimensional upper and lower bounds on decodable thresholds of Zopfm and binary low-density parity-check (LDPC) codes, assuming belief propagation decoding on memoryless channels. A concrete framework is presented, admitting systematic searches for new bounds. Two noise measures are considered: the Bhattacharyya noise parameter and the soft bit value for a ma... View full abstract»

• ### LP Decoding Corrects a Constant Fraction of Errors

Publication Year: 2007, Page(s):82 - 89
Cited by:  Papers (59)
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We show that for low-density parity-check (LDPC) codes whose Tanner graphs have sufficient expansion, the linear programming (LP) decoder of Feldman, Karger, and Wainwright can correct a constant fraction of errors. A random graph will have sufficient expansion with high probability, and recent work shows that such graphs can be constructed efficiently. A key element of our method is the use of a ... View full abstract»

• ### Improved Upper Bounds on Stopping Redundancy

Publication Year: 2007, Page(s):90 - 104
Cited by:  Papers (41)
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For a linear block code with minimum distance d, its stopping redundancy is the minimum number of check nodes in a Tanner graph representation of the code, such that all nonempty stopping sets have size d or larger. We derive new upper bounds on stopping redundancy for all linear codes in general, and for maximum distance separable (MDS) codes specifically, and show how they improve upon previous ... View full abstract»

• ### Reliability-Based Soft-Decision Decoding With Multiple Biases

Publication Year: 2007, Page(s):105 - 120
Cited by:  Papers (16)  |  Patents (1)
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In this paper, a new reliability-based soft-decision decoding algorithm is presented. This algorithm repeatedly uses biased reliability values to construct the most-reliable-basis (MRB). As a result, this new method makes use of multiple information sets in a stochastic way. Compared to previously proposed competitive approaches, this new method produces a more efficient MRB reprocessing type algo... View full abstract»

• ### Construction of Regular and Irregular LDPC Codes: Geometry Decomposition and Masking

Publication Year: 2007, Page(s):121 - 134
Cited by:  Papers (87)  |  Patents (3)
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Two algebraic methods for systematic construction of structured regular and irregular low-density parity-check (LDPC) codes with girth of at least six and good minimum distances are presented. These two methods are based on geometry decomposition and a masking technique. Numerical results show that the codes constructed by these methods perform close to the Shannon limit and as well as random-like... View full abstract»

• ### Constructions for $q$-Ary Constant-Weight Codes

Publication Year: 2007, Page(s):135 - 146
Cited by:  Papers (29)
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This paper introduces a new combinatorial construction for q-ary constant-weight codes which yields several families of optimal codes and asymptotically optimal codes. The construction reveals intimate connection between q-ary constant-weight codes and sets of pairwise disjoint combinatorial designs of various types View full abstract»

• ### Complete Distances of All Negacyclic Codes of Length$2^{s}$Over$\BBZ _{2^{a}}$

Publication Year: 2007, Page(s):147 - 161
Cited by:  Papers (24)
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Various kinds of distances of all negacyclic codes of length 2sover Zopf2aare completely determined. Using our structure theorems of negacyclic codes of length 2sover Zopf2a, we first calculate the Hamming distances of all such negacyclic codes, which particularly lead to the Hamming weight distributions and Hamming weight enumerato... View full abstract»

• ### Improving the Upper Bounds on the Covering Radii of Binary Reed&ndash;Muller Codes

Publication Year: 2007, Page(s):162 - 173
Cited by:  Papers (29)
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By deriving bounds on character sums of Boolean functions and by using the characterizations, due to Kasami , of those elements of the Reed-Muller codes whose Hamming weights are smaller than twice and a half the minimum distance, we derive an improved upper bound on the covering radius of the Reed-Muller code of order 2, and we deduce improved upper bounds on the covering radii of the Reed-Muller... View full abstract»

• ### Multipath Aided Rapid Acquisition: Optimal Search Strategies

Publication Year: 2007, Page(s):174 - 193
Cited by:  Papers (73)
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In this paper, we propose a search technique that takes advantage of multipath, which has long been considered deleterious for efficient communication, to aid the sequence acquisition in dense multipath channels. We consider a class of serial-search strategies and use optimization and convexity theories to determine fundamental limits of achievable mean acquisition times (MATs). In particular, we ... View full abstract»

• ### Channel Uncertainty in Ultra-Wideband Communication Systems

Publication Year: 2007, Page(s):194 - 208
Cited by:  Papers (28)
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Channel uncertainty limits the achievable data rates of certain ultra-wideband systems due to the need to estimate the channel. The use of bursty duty-cycled transmission reduces the channel uncertainty because the receiver has to estimate the channel only when transmission takes place, but the maximum amount of burstiness and hence the possible reduction of channel uncertainty both depend on the ... View full abstract»

• ### Optimal Joint Detection/Estimation in Fading Channels With Polynomial Complexity

Publication Year: 2007, Page(s):209 - 223
Cited by:  Papers (37)
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The problem of sequence detection in frequency-nonselective/time-selective fading channels, when channel state information (CSI) is not available at the transmitter and receiver, is considered in this paper. The traditional belief is that exact maximum-likelihood sequence detection (MLSD) of an uncoded sequence over this channel has exponential complexity in the channel coherence time. Thus, for s... View full abstract»

• ### Gray Coding for Multilevel Constellations in Gaussian Noise

Publication Year: 2007, Page(s):224 - 235
Cited by:  Papers (39)  |  Patents (2)
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The problem of finding the optimal labeling (bit-to-symbol mapping) of multilevel coherent phase shift keying (PSK), pulse amplitude modulation (PAM), and quadrature amplitude modulation (QAM) constellations with respect to minimizing the bit-error probability (BEP) over a Gaussian channel is addressed. We show that using the binary reflected Gray code (BRGC) to label the signal constellation resu... View full abstract»

• ### How Good Is PSK for Peak-Limited Fading Channels in the Low-SNR Regime?

Publication Year: 2007, Page(s):236 - 251
Cited by:  Papers (15)
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This paper investigates the achievable information rate of phase-shift keying (PSK) over frequency nonselective Rayleigh and Rician fading channels without channel state information (CSI). The fading process exhibits general temporal correlation characterized by its spectral density function. We consider both discrete-time and continuous-time channels, and find their asymptotics at low signal-to-n... View full abstract»

• ### Asymptotic Analysis of Spatially Correlated MIMO Multiple-Access Channels With Arbitrary Signaling Inputs for Joint and Separate Decoding

Publication Year: 2007, Page(s):252 - 268
Cited by:  Papers (44)
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While the capacity of a single-user, point-to-point, multiple-input multiple-output (MIMO) channel has been well known, the achievable capacity of a MIMO channel in the presence of other co-channel users is much less understood. One such important scenario is the multiple-access (MA) channel where communication occurs from many uncoordinated mobile users to a common base station receiver (i.e., mu... View full abstract»

• ### Guessing Under Source Uncertainty

Publication Year: 2007, Page(s):269 - 287
Cited by:  Papers (35)
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This paper considers the problem of guessing the realization of a finite alphabet source when some side information is provided. The only knowledge the guesser has about the source and the correlated side information is that the joint source is one among a family. A notion of redundancy is first defined and a new divergence quantity that measures this redundancy is identified. This divergence quan... View full abstract»

• ### $\epsilon$-Capacity of Binary Symmetric Averaged Channels

Publication Year: 2007, Page(s):288 - 303
Cited by:  Papers (9)
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We consider the channel model obtained by averaging binary symmetric channel (BSC) components with respect to a weighting distribution. A nonempty open interval (A, B) is called a capacity gap for this channel model if no channel component has capacity in (A, B) and this property fails for every open interval strictly containing (A, B). For a fixed epsi>0, suppose one wishes to compute the epsi... View full abstract»

• ### Asymptotically Optimal Multiple-Access Communication Via Distributed Rate Splitting

Publication Year: 2007, Page(s):304 - 319
Cited by:  Papers (10)
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We consider the multiple-access communication problem in a distributed setting for both the additive white Gaussian noise channel and the discrete memoryless channel. We propose a scheme called Distributed Rate Splitting to achieve the optimal rates allowed by information theory in a distributed manner. In this scheme, each real user creates a number of virtual users via a power/rate splitting mec... View full abstract»

## 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
Alexander Barg

Department of Electrical and Computer Engineering and the Institute for Systems Research, University of Maryland

email: abarg-ittrans@ece.umd.edu