IEEE Transactions on Information Theory

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Publication Year: 2008, Page(s):C1 - C4
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• IEEE Transactions on Information Theory publication information

Publication Year: 2008, Page(s): C2
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• Error Exponents for Variable-Length Block Codes With Feedback and Cost Constraints

Publication Year: 2008, Page(s):945 - 963
Cited by:  Papers (8)
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Variable-length block-coding schemes are investigated for discrete memoryless channels with ideal feedback under cost constraints. Upper and lower bounds are found for the minimum achievable probability of decoding error Pe,min as a function of constraints R, P, and tau on the transmission rate, average cost, and average block length, respectively. For given R and P, the lower and upper bounds to ... View full abstract»

• Lautum Information

Publication Year: 2008, Page(s):964 - 975
Cited by:  Papers (14)
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A popular way to measure the degree of dependence between two random objects is by their mutual information, defined as the divergence between the joint and product-of-marginal distributions. We investigate an alternative measure of dependence: the lautum information defined as the divergence between the product-of-marginal and joint distributions, i.e., swapping the arguments in the definition of... View full abstract»

• Multiple-Access Channels With Confidential Messages

Publication Year: 2008, Page(s):976 - 1002
Cited by:  Papers (189)
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A discrete memoryless multiple-access channel (MAC) with confidential messages is studied, where two users attempt to transmit common information to a destination and each user also has private (confidential) information intended for the destination. This channel generalizes the classical MAC model in that each user also receives channel outputs, and hence may obtain the confidential information s... View full abstract»

• An Algebraic, Analytic, and Algorithmic Investigation on the Capacity and Capacity-Achieving Input Probability Distributions of Finite-Input– Finite-Output Discrete Memoryless Channels

Publication Year: 2008, Page(s):1003 - 1023
Cited by:  Papers (10)
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In this paper, we investigate the capacity and capacity-achieving input probability distributions (IPDs) of finite-input-finite-output discrete memoryless channels (DMCs). In the general respect, we establish a novel and simple characterization for the capacity-achieving IPDs of a DMC, which is equivalent to the conventional Kuhn-Tucker conditions. We then prove a conjecture of Majani and Rumsey, ... View full abstract»

• Bounds for Codes in Products of Spaces, Grassmann, and Stiefel Manifolds

Publication Year: 2008, Page(s):1024 - 1035
Cited by:  Papers (8)
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Upper bounds are derived for codes in Stiefel and Grassmann manifolds with given minimum chordal distance. They stem from upper bounds for codes in the product of unit spheres and projective spaces. The new bounds are asymptotically better than the previously known ones. View full abstract»

• Soft-Output BEAST Decoding With Application to Product Codes

Publication Year: 2008, Page(s):1036 - 1049
Cited by:  Papers (2)
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A bidirectional efficient algorithm for searching code trees (BEAST) is proposed for efficient soft-output decoding of block codes and concatenated block codes. BEAST operates on trees corresponding to the minimal trellis of a block code and finds a list of the most probable codewords. The complexity of the BEAST search is significantly lower than the complexity of trellis-based algorithms, such a... View full abstract»

• On the Hardness of Decoding the Gale–Berlekamp Code

Publication Year: 2008, Page(s):1050 - 1060
Cited by:  Papers (4)
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The Gale-Berlekamp (in short, GB) code is the dual code of the binary product code in which the horizontal and vertical constituent codes are both the parity code. It is shown that the problem of deciding whether there is a codeword of the GB code within a prescribed distance from a given received word, is NP-complete. The problem remains hard (in a well-defined sense) even if the decoder is allow... View full abstract»

• A New Linear Programming Approach to Decoding Linear Block Codes

Publication Year: 2008, Page(s):1061 - 1072
Cited by:  Papers (34)
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In this paper, we propose a new linear programming formulation for the decoding of general linear block codes. Different from the original formulation given by Feldman, the number of total variables to characterize a parity-check constraint in our formulation is less than twice the degree of the corresponding check node. The equivalence between our new formulation and the original formulation is p... View full abstract»

• A Quasi-Random Approach to Space–Time Codes

Publication Year: 2008, Page(s):1073 - 1085
Cited by:  Papers (18)  |  Patents (1)
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This paper presents a quasi-random approach to space-time (ST) codes. The basic principle is to transmit randomly interleaved versions of forward error correction (FEC)-coded sequences simultaneously from all antennas in a multilayer structure. This is conceptually simple, yet still very effective. It is also flexible regarding the transmission rate, antenna numbers, and channel conditions (e.g., ... View full abstract»

• On the User Selection for MIMO Broadcast Channels

Publication Year: 2008, Page(s):1086 - 1107
Cited by:  Papers (62)  |  Patents (1)
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In this paper, a downlink communication system, in which a base station (BS) equipped with antennas communicates with users each equipped with receive antennas, is considered. An efficient suboptimum algorithm is proposed for selecting a set of users in order to maximize the sum-rate throughput of the system, in a Rayleigh-fading environment. For the asymptotic case when tends to infinity, the nec... View full abstract»

• Quantization Bounds on Grassmann Manifolds and Applications to MIMO Communications

Publication Year: 2008, Page(s):1108 - 1123
Cited by:  Papers (122)  |  Patents (2)
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The Grassmann manifold G<sub>n,p</sub> (L) is the set of all p-dimensional planes (through the origin) in the n-dimensional Euclidean space L<sup>n</sup>, where L is either R or C. This paper considers the quantization problem in which a source in G<sub>n,p</sub> (L) is quantized through a code in G<sub>n,q</sub> (L), with p and q not necessarily the... View full abstract»

• Broadcast in MIMO Systems Based on a Generalized QR Decomposition: Signaling and Performance Analysis

Publication Year: 2008, Page(s):1124 - 1138
Cited by:  Papers (40)
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A simple signaling method for broadcast channels with multiple-transmit multiple-receive antennas is proposed. In this method, for each user, the direction in which the user has the maximum gain is determined. The best user in terms of the largest gain is selected. The corresponding direction is used as the modulation vector (MV) for the data stream transmitted to the selected user. The algorithm ... View full abstract»

• On the Derivation of the Exact, Closed-Form Capacity Formulas for Receiver-Sided Correlated MIMO Channels

Publication Year: 2008, Page(s):1139 - 1161
Cited by:  Papers (9)
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This paper solves the problem of finding a closed-form expression for the average information-theoretic capacity of wireless systems with an arbitrary number of transmitter and receiver antennas. It is assumed that only the receivers have (perfect) knowledge of the channel state and that fading correlation is receiver-sided. The main purpose of the paper is accomplished by introducing a few very s... View full abstract»

• Analysis and Optimization of Diagonally Layered Lattice Schemes for MIMO Fading Channels

Publication Year: 2008, Page(s):1162 - 1185
Cited by:  Papers (7)
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Embodiments of the diagonal Bell Laboratories layered space-time (D-BLAST) architecture for multiple-input-multiple-output (MIMO) communication are developed wherein information symbol vectors are encoded using codewords from a lattice code [called a diagonally layered lattice (DLL) code], which are formatted onto the diagonals of a space-time frame. Decoding is done using a sphere decoder for eac... View full abstract»

• Diversity–Multiplexing Tradeoff and Outage Performance for Rician MIMO Channels

Publication Year: 2008, Page(s):1186 - 1196
Cited by:  Papers (19)
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In this paper, we analyze the diversity-multiplexing tradeoff (DMT), originally introduced by Zheng and Tse, and outage performance for Rician multiple-input-multiple-output (MIMO) channels. The DMT characteristics of Rayleigh and Rician channels are shown to be identical. In a high signal-to-noise ratio (SNR) regime, the log-log plot of outage probability versus SNR curve for a Rician channel is ... View full abstract»

• User Cooperation in the Absence of Phase Information at the Transmitters

Publication Year: 2008, Page(s):1197 - 1206
Cited by:  Papers (2)
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In this paper, a multiuser communication system in which wireless users cooperate to transmit information to a base station is considered. The proposed scheme can significantly enlarge the achievable rate region, provided that the wireless connections between pairs of cooperating users are stronger than the connection from every user to the base station. The gains in transmission rate remain subst... View full abstract»

• Incremental Redundancy Cooperative Coding for Wireless Networks: Cooperative Diversity, Coding, and Transmission Energy Gains

Publication Year: 2008, Page(s):1207 - 1224
Cited by:  Papers (41)
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We study an incremental redundancy (IR) cooperative coding scheme for wireless networks. To exploit the distributed spatial diversity we propose a cluster-based collaborating strategy for a quasi-static Rayleigh-fading channel model. Our scheme allows for enhancing the reliability performance of a direct communication over a single hop. The collaborative cluster consists of M - 1 nodes between the... View full abstract»

• Power-Efficient Resource Allocation for Time-Division Multiple Access Over Fading Channels

Publication Year: 2008, Page(s):1225 - 1240
Cited by:  Papers (34)
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We investigate resource allocation policies for time-division multiple access (TDMA) over fading channels in the power-limited regime. For frequency-flat block-fading channels and transmitters having full channel state information (CSI), we first minimize power under a weighted sum average rate constraint and show that the optimal rate and time allocation policies can be obtained by a greedy water... View full abstract»

• Max-Product for Maximum Weight Matching: Convergence, Correctness, and LP Duality

Publication Year: 2008, Page(s):1241 - 1251
Cited by:  Papers (69)
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Max-product "belief propagation" (BP) is an iterative, message-passing algorithm for finding the maximum a posteriori (MAP) assignment of a discrete probability distribution specified by a graphical model. Despite the spectacular success of the algorithm in many application areas such as iterative decoding and combinatorial optimization, which involve graphs with many cycles, theoretical results a... View full abstract»

• Randomness Criteria in Terms of${\alpha }$-Divergences

Publication Year: 2008, Page(s):1252 - 1261
Cited by:  Papers (1)
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Vovk's randomness criterion characterizes sequences that are random relative to two distinct computable probability measures. The uniqueness of the criterion lies in the fact that, unlike the standard criterion based on the likelihood ratio test, it is expressed in terms of a geometrical quantity, the Hellinger distance, on the space of probability measures. In this paper, we generalize the random... View full abstract»

• Recursive Lower Bounds on the Nonlinearity Profile of Boolean Functions and Their Applications

Publication Year: 2008, Page(s):1262 - 1272
Cited by:  Papers (35)
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The nonlinearity profile of a Boolean function (i.e., the sequence of its minimum Hamming distances nl<sub>r</sub>(f) to all functions of degrees at most r, for r ges 1) is a cryptographic criterion whose role against attacks on stream and block ciphers has been illustrated by many papers. It plays also a role in coding theory, since it is related to the covering radii of Reed-Muller c... View full abstract»

• Optimal Prefix Codes for Infinite Alphabets With Nonlinear Costs

Publication Year: 2008, Page(s):1273 - 1286
Cited by:  Papers (11)  |  Patents (3)
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Let P={p(i)} be a measure of strictly positive probabilities on the set of nonnegative integers. Although the countable number of inputs prevents usage of the Huffman algorithm, there are nontrivial P for which known methods find a source code that is optimal in the sense of minimizing expected codeword length. For some applications, however, a source code should instead minimize one of a family o... View full abstract»

• Network Coding Capacity With a Constrained Number of Coding Nodes

Publication Year: 2008, Page(s):1287 - 1291
Cited by:  Papers (11)
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We study network coding capacity under a constraint on the total number of network nodes that can perform coding. That is, only a certain number of network nodes can produce coded outputs, whereas the remaining nodes are limited to performing routing. We prove that every nonnegative, monotonically nondecreasing, eventually constant, rational-valued function on the nonnegative integers is equal to ... 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