# IEEE Transactions on Information Theory

## Filter Results

Displaying Results 1 - 25 of 39

Publication Year: 2009, Page(s):C1 - C4
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• ### IEEE Transactions on Information Theory publication information

Publication Year: 2009, Page(s): C2
| PDF (41 KB)
• ### The Capacity of Wireless Networks: Information-Theoretic and Physical Limits

Publication Year: 2009, Page(s):3413 - 3424
Cited by:  Papers (114)
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It is shown that the capacity scaling of wireless networks is subject to a fundamental limitation which is independent of power attenuation and fading models. It is a degrees of freedom limitation which is due to the laws of physics. By distributing uniformly an order of <i>n</i> users wishing to establish pairwise independent communications at fixed wavelength inside a two-dimensional... View full abstract»

• ### Hierarchical Cooperation in <emphasis emphasistype="italic">Ad Hoc</emphasis> Networks: Optimal Clustering and Achievable Throughput

Publication Year: 2009, Page(s):3425 - 3436
Cited by:  Papers (34)
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For a wireless network with <i>n</i> nodes distributed in an area <i>A</i>, and with <i>n</i> source-destination pairs communicating with each other at some common rate, the hierarchical cooperation scheme proposed in (Ozgur, Leveque, and Tse, 2007) is analyzed and optimized by choosing the number of hierarchical stages and the corresponding cluster sizes that m... View full abstract»

• ### Stability, Fairness, and Performance: A Flow-Level Study on Nonconvex and Time-Varying Rate Regions

Publication Year: 2009, Page(s):3437 - 3456
Cited by:  Papers (10)
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The flow-level stability and performance of data networks with utility-maximizing allocations are studied in this paper. Similarly to prior works on flow-level models, exogenous data arrivals with finite workloads are considered. However, to model many realistic situations, the rate region, which constrains the feasibility of resource allocation, may be either nonconvex or time-varying. When the r... View full abstract»

• ### Uplink Macro Diversity of Limited Backhaul Cellular Network

Publication Year: 2009, Page(s):3457 - 3478
Cited by:  Papers (131)  |  Patents (2)
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In this work, new achievable rates are derived for the uplink channel of a cellular network with joint multicell processing (MCP), where unlike previous results, the ideal backhaul network has finite capacity per cell. Namely, the cell sites are linked to the central joint processor via lossless links with finite capacity. The new rates are based on compress-and-forward schemes combined with local... View full abstract»

• ### Guessing Facets: Polytope Structure and Improved LP Decoder

Publication Year: 2009, Page(s):3479 - 3487
Cited by:  Papers (21)
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We investigate the structure of the polytope underlying the linear programming (LP) decoder introduced by Feldman, Karger, and Wainwright. We first show that for expander codes, every fractional pseudocodeword always has at least a constant fraction of nonintegral bits. We then prove that for expander codes, the active set of any fractional pseudocodeword is smaller by a constant fraction than tha... View full abstract»

• ### On the Stopping Distance of Array Code Parity-Check Matrices

Publication Year: 2009, Page(s):3488 - 3493
Cited by:  Papers (21)
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For q an odd prime and 1 les m les q, we study two binary qm times q<sup>2</sup> parity check matrices for binary array codes. For both parity check matrices, we determine the stopping distance and the minimum distance of the associated code for 2 les m les 3, and for (m, q)=(4, 5). In the case (m, q)=(4, 7), the stopping distance and the related minimum distance are also determined fo... View full abstract»

• ### Moment Balancing Templates: Constructions to Add Insertion/Deletion Correction Capability to Error Correcting or Constrained Codes

Publication Year: 2009, Page(s):3494 - 3500
Cited by:  Papers (5)
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Templates are constructed to extend arbitrary additive error correcting or constrained codes, i.e., additional redundant bits are added in selected positions to balance the moment of the codeword. The original codes may have error correcting capabilities or constrained output symbols as predetermined by the usual communication system considerations, which are retained after extending the code. Usi... View full abstract»

• ### On Minimal Tree Realizations of Linear Codes

Publication Year: 2009, Page(s):3501 - 3519
Cited by:  Papers (9)
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A tree decomposition of the coordinates of a code is a mapping from the coordinate set to the set of vertices of a tree. A tree decomposition can be extended to a tree realization, i.e., a cycle-free realization of the code on the underlying tree, by specifying a state space at each edge of the tree, and a local constraint code at each vertex of the tree. The constraint complexity of a tree realiz... View full abstract»

• ### Constructing Proper Codes for Error Detection

Publication Year: 2009, Page(s):3520 - 3525
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It is shown that for any alphabet size <i>q</i> and any code size <i>M</i>, there exist proper codes for error detection on a <i>q</i>-ary symmetric channel for all sufficiently large lengths. The stronger condition <i>zero-strong</i> <i>proper</i> code is defined. It is shown that such codes can only exist for <i>q</i> dividi... View full abstract»

• ### Design and Analysis of Successive Decoding With Finite Levels for the Markov Channel

Publication Year: 2009, Page(s):3526 - 3543
Cited by:  Papers (4)
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This paper proposes a practical successive decoding scheme with finite levels for the finite-state Markov channels (FSMCs) where there is no a priori state information at the transmitter or the receiver. The design employs either a random interleaver or a deterministic interleaver with an irregular pattern and an optional iterative estimation and decoding procedure within each level. The interleav... View full abstract»

• ### Nonlinear Index Coding Outperforming the Linear Optimum

Publication Year: 2009, Page(s):3544 - 3551
Cited by:  Papers (58)
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The following source coding problem was introduced by Birk and Kol: a sender holds a word x isin {0, 1}<sup>n</sup>, and wishes to broadcast a codeword to n receivers, R<sub>n</sub>,..., R<sub>n</sub>. The receiver R<sub>i</sub> is interested in x<sub>i</sub>, and has prior side information comprising some subset of the n bits. This corre... View full abstract»

• ### Perfect Codes From Cayley Graphs Over Lipschitz Integers

Publication Year: 2009, Page(s):3552 - 3562
Cited by:  Papers (12)
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The search for perfect error-correcting codes has received intense interest since the seminal work by Hamming. Decades ago, Golomb and Welch studied perfect codes for the Lee metric in multidimensional torus constellations. In this work, we focus our attention on a new class of four-dimensional signal spaces which include tori as subcases. Our constellations are modeled by means of Cayley graphs d... View full abstract»

• ### On Certain Values of Kloosterman Sums

Publication Year: 2009, Page(s):3563 - 3564
Cited by:  Papers (4)
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Let <i>K</i> <sub>q</sub> <sup>n</sup>(<i>a</i>) be a Kloosterman sum over the finite field <i>F</i> <sub>q</sub> <sup>n</sup> of characteristic <i>p</i> . In this note so called subfield conjecture is proved: if <i>a</i> ne 0 belongs to the proper subfield <i>F</i> <sub>q&... View full abstract»

• ### On Row-by-Row Coding for 2-D Constraints

Publication Year: 2009, Page(s):3565 - 3576
Cited by:  Papers (6)
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A constant-rate encoder-decoder pair is presented for a fairly large family of two-dimensional (2-D) constraints. Encoding and decoding is done in a row-by-row manner, and is sliding-block decodable. Essentially, the 2-D constraint is turned into a set of independent and relatively simple one-dimensional (1-D) constraints; this is done by dividing the array into fixed-width vertical strips. Each r... View full abstract»

• ### Bounds on the Sum Capacity of Synchronous Binary CDMA Channels

Publication Year: 2009, Page(s):3577 - 3593
Cited by:  Papers (12)
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In this paper, we obtain a family of lower bounds for the sum capacity of code-division multiple-access (CDMA) channels assuming binary inputs and binary signature codes in the presence of additive noise with an arbitrary distribution. The envelope of this family gives a relatively tight lower bound in terms of the number of users, spreading gain, and the noise distribution. The derivation methods... View full abstract»

• ### Channels That Heat Up

Publication Year: 2009, Page(s):3594 - 3612
Cited by:  Papers (20)
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This paper considers an additive noise channel where the time-A; noise variance is a weighted sum of the squared magnitudes of the previous channel inputs plus a constant. This channel model accounts for the dependence of the intrinsic thermal noise on the data due to the heat dissipation associated with the transmission of data in electronic circuits: the data determine the transmitted signal, wh... View full abstract»

• ### Hessian and Concavity of Mutual Information, Differential Entropy, and Entropy Power in Linear Vector Gaussian Channels

Publication Year: 2009, Page(s):3613 - 3628
Cited by:  Papers (47)  |  Patents (1)
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Within the framework of linear vector Gaussian channels with arbitrary signaling, the Jacobian of the minimum mean square error and Fisher information matrices with respect to arbitrary parameters of the system are calculated in this paper. Capitalizing on prior research where the minimum mean square error and Fisher information matrices were linked to information-theoretic quantities through diff... View full abstract»

• ### Feedback Capacity of the Compound Channel

Publication Year: 2009, Page(s):3629 - 3644
Cited by:  Papers (18)
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In this work, we find the capacity of a compound finite-state channel (FSC) with time-invariant deterministic feedback. We consider the use of fixed length block codes over the compound channel. Our achievability result includes a proof of the existence of a universal decoder for the family of FSCs with feedback. As a consequence of our capacity result, we show that feedback does not increase the ... View full abstract»

• ### On the Entropy of Compound Distributions on Nonnegative Integers

Publication Year: 2009, Page(s):3645 - 3650
Cited by:  Papers (10)
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Some entropy comparison results are presented concerning compound distributions on nonnegative integers. The main result shows that, under a log-concavity assumption, two compound distributions are ordered in terms of Shannon entropy if both the ldquonumbers of claimsrdquo and the ldquoclaim sizesrdquo are ordered accordingly in the convex order. Several maximum/minimum entropy theorems follow as ... View full abstract»

• ### The Effect of Finite Rate Feedback on CDMA Signature Optimization and MIMO Beamforming Vector Selection

Publication Year: 2009, Page(s):3651 - 3669
Cited by:  Papers (8)
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We analyze the effect of finite rate feedback on code-division multiple-access (CDMA) signature optimization and multiple-input multiple-output (MIMO) beamforming vector selection. In CDMA signature optimization, for a particular user, the receiver selects a signature vector from a codebook to best avoid interference from other users, and then feeds the corresponding index back to the specified us... View full abstract»

• ### Asymptotic Theorems for the Product of Certain Structured Random Matrices and Their Application to Analysis of Asynchronous CDMA

Publication Year: 2009, Page(s):3670 - 3700
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This paper consists of two parts. In the first part, asymptotic theorems about the product of certain structured random matrices are developed by means of the moment convergence theorem (MCT) and the free probability theory. This product of random matrices is a generalization of the product of a sample covariance matrix and an arbitrary Hermitian matrix. In the second part, the theoretical results... View full abstract»

• ### On the Monotonicity of the Generalized Marcum and Nuttall${Q}$-Functions

Publication Year: 2009, Page(s):3701 - 3710
Cited by:  Papers (41)
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Monotonicity criteria are established for the generalized MarcumQ-function,QM(alpha,beta), the standard NuttallQ-function,QM,N(alpha,beta) , and the normalized NuttallQ-function,QM,N(alpha,beta), with respect to their real order indicesM,N. Besides, closed-form expressions are derived for the computation of the standard and norm... View full abstract»

• ### SCALE: A Low-Complexity Distributed Protocol for Spectrum Balancing in Multiuser DSL Networks

Publication Year: 2009, Page(s):3711 - 3724
Cited by:  Papers (162)  |  Patents (2)
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Dynamic spectrum management of digital subscriber lines (DSLs) has the potential to dramatically increase the capacity of the aging last-mile copper access network. This paper takes an important step toward fulfilling this potential through power spectrum balancing. We derive a novel algorithm called SCALE, that provides a significant performance improvement over the existing iterative water-filli... 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