# IEEE Transactions on Information Theory

## Filter Results

Displaying Results 1 - 25 of 54

Publication Year: 2007, Page(s):C1 - C4
| PDF (50 KB)
• ### IEEE Transactions on Information Theory publication information

Publication Year: 2007, Page(s): C2
| PDF (38 KB)
• ### Perfect Space–Time Codes for Any Number of Antennas

Publication Year: 2007, Page(s):3853 - 3868
Cited by:  Papers (84)  |  Patents (4)
| | PDF (573 KB) | HTML

In a recent paper, perfect (ntimesn) space-time codes were introduced as the class of linear dispersion space-time (ST) codes having full rate, nonvanishing determinant, a signal constellation isomorphic to either the rectangular or hexagonal lattices in 2n2dimensions, and uniform average transmitted energy per antenna. Consequence of these conditions include optima... View full abstract»

• ### A Near-Maximum-Likelihood Decoding Algorithm for MIMO Systems Based on Semi-Definite Programming

Publication Year: 2007, Page(s):3869 - 3886
Cited by:  Papers (45)
| | PDF (576 KB) | HTML

In multiple-input multiple-output (MIMO) systems, maximum-likelihood (ML) decoding is equivalent to finding the closest lattice point in an <i>N</i>-dimensional complex space. In general, this problem is known to be NP-hard. In this paper, a quasi-ML algorithm based on semi-definite programming (SDP) is proposed. We introduce several SDP relaxation models for MIMO systems, with increas... View full abstract»

• ### On the Outage Capacity of Correlated Multiple-Path MIMO Channels

Publication Year: 2007, Page(s):3887 - 3903
Cited by:  Papers (38)
| | PDF (598 KB) | HTML

The use of multiple-antenna arrays can dramatically increase the throughput of wireless communication systems. Thus, it is important to characterize the statistics of the mutual information for realistic correlated channels. Here, a mathematical approach is presented, using the method of replicas, that provides analytic expressions not only for the average, but also for the higher moments of the d... View full abstract»

• ### The Cost of Uncorrelation and Noncooperation in MIMO Channels

Publication Year: 2007, Page(s):3904 - 3920
| | PDF (437 KB) | HTML

We investigate the capacity loss for using uncorrelated Gaussian input over a multiple-input multiple-output (MIMO) linear additive-noise channel. We upper-bound the capacity loss by a universal constant C* which is independent of the channel matrix and the noise distribution. For a single-user MIMO channel with n<sub>t</sub> inputs and n<sub>r</sub> outputs C* = min [ 1/2,... View full abstract»

• ### Diagonal Lattice Space–Time Codes From Number Fields and Asymptotic Bounds

Publication Year: 2007, Page(s):3921 - 3926
Cited by:  Papers (8)
| | PDF (192 KB) | HTML

In this paper, we reformulate some constructions of real and complex diagonal lattice space-time codes from number fields which have been given explicitly or implicitly by other researchers. These constructions establish a connection between good diagonal lattice space-time codes and number fields with small absolute values of discriminants. We present two tables for diversity products of some lat... View full abstract»

• ### Multirecipient Encryption Schemes: How to Save on Bandwidth and Computation Without Sacrificing Security

Publication Year: 2007, Page(s):3927 - 3943
Cited by:  Papers (18)
| | PDF (412 KB) | HTML

This paper proposes several new schemes which allow a sender to send encrypted messages to multiple recipients more efficiently (in terms of bandwidth and computation) than by using a standard encryption scheme. Most of the proposed schemes explore a new natural technique called randomness reuse. In order to analyze security of our constructions, we introduce a new notion of multirecipient encrypt... View full abstract»

• ### A New Criterion for Nonlinearity of Block Ciphers

Publication Year: 2007, Page(s):3944 - 3957
| | PDF (322 KB) | HTML

For years, the cryptographic community has searched for good nonlinear functions. Bent functions, almost perfect nonlinear functions, and similar constructions have been suggested as a good base for cryptographic applications due to their highly nonlinear nature. In the first part of this paper, we examine using these functions as block ciphers, and present several distinguishers between almost pe... View full abstract»

• ### Exact Probabilistic Analysis of Memoryless Combiners

Publication Year: 2007, Page(s):3958 - 3972
| | PDF (320 KB) | HTML

Exact analytical expressions for various probability distributions in a type of stream ciphers known as memoryless combiners are derived. They relate to arbitrary linear functions and subvectors of output bits as well as to arbitrary linear functions and subvectors of input bits when the output sequence is assumed to be given. Practical approximations to the exact expressions to be used in one-ste... View full abstract»

• ### Multiplicative Linear Secret Sharing Schemes Based on Connectivity of Graphs

Publication Year: 2007, Page(s):3973 - 3978
Cited by:  Papers (8)
| | PDF (186 KB) | HTML

The multiplicative property is important for a linear secret sharing scheme (LSSS) to be used in constructing a multiparty computation (MPC) protocol. In general, an LSSS has to expand its share size to obtain the multiplicative property. In this paper, with respect to an MPC problem based on connectivity of graphs we devise an ideal multiplicative LSSS, that is, the LSSS is of the multiplicative ... View full abstract»

• ### Single-Bit Oversampled A/D Conversion With Exponential Accuracy in the Bit Rate

Publication Year: 2007, Page(s):3979 - 3989
Cited by:  Papers (33)
| | PDF (328 KB) | HTML

A scheme for simple oversampled analog-to-digital (A/D) conversion using single-bit quantization is presented. The scheme is based on recording positions of zero-crossings of the input signal added to a deterministic dither function. This information can be represented in a manner such that the bit rate increases only logarithmically with the oversampling factor <i>r</i>. The input ban... View full abstract»

• ### Lagrangian Optimization of Two-Description Scalar Quantizers

Publication Year: 2007, Page(s):3990 - 4012
Cited by:  Papers (16)
| | PDF (629 KB) | HTML

In this paper, we study the problem of optimal design of balanced two-description fixed-rate scalar quantizer (2DSQ) under the constraint of convex codecells. Using a graph-based approach to model the problem, we show that the minimum expected distortion of the 2DSQ is a convex function of the number of codecells in the side quantizers. This property allows the problem to be solved by Lagrangian m... View full abstract»

• ### Pseudocodewords of Tanner Graphs

Publication Year: 2007, Page(s):4013 - 4038
Cited by:  Papers (51)
| | PDF (3298 KB) | HTML

This paper presents a detailed analysis of pseudocodewords of Tanner graphs. Pseudocodewords arising on the iterative decoder's computation tree are distinguished from pseudocodewords arising on finite degree lifts. Lower bounds on the minimum pseudocodeword weight are presented for the BEC, BSC, and AWGN channel. Some structural properties of pseudocodewords are examined, and pseudocodewords and ... View full abstract»

• ### On Capacity of Line Networks

Publication Year: 2007, Page(s):4039 - 4058
Cited by:  Papers (18)
| | PDF (505 KB) | HTML

We consider communication through a cascade of discrete memoryless channels (DMCs). The source and destination node of this cascade are allowed to use coding schemes of arbitrary complexity, but the intermediate relay nodes are restricted to process only blocks of a fixed length. We investigate how the processing at the relays must be chosen in order to maximize the capacity of the cascade, that i... View full abstract»

• ### Turbo Decoding on the Binary Erasure Channel: Finite-Length Analysis and Turbo Stopping Sets

Publication Year: 2007, Page(s):4059 - 4075
Cited by:  Papers (18)
| | PDF (887 KB) | HTML

This paper is devoted to the finite-length analysis of turbo decoding over the binary erasure channel (BEC). The performance of iterative belief-propagation decoding of low-density parity-check (LDPC) codes over the BEC can be characterized in terms of <i>stopping sets</i>. We describe turbo decoding on the BEC which is simpler than turbo decoding on other channels. We then adapt the c... View full abstract»

• ### Efficient Serial Message-Passing Schedules for LDPC Decoding

Publication Year: 2007, Page(s):4076 - 4091
Cited by:  Papers (79)  |  Patents (12)
| | PDF (927 KB) | HTML

Conventionally, in each low-density parity-check (LDPC) decoding iteration all the variable nodes and subsequently all the check nodes send messages to their neighbors (flooding schedule). An alternative, more efficient, approach is to update the nodes' messages serially (serial schedule). A theoretical analysis of serial message passing decoding schedules is presented. In particular, the evolutio... View full abstract»

• ### Constructions of Fault-Tolerant Optical 2-to-1 FIFO Multiplexers

Publication Year: 2007, Page(s):4092 - 4105
Cited by:  Papers (8)
| | PDF (437 KB) | HTML

Recent advances in the literature have shown that there exist systematic switched delay lines (SDL) construction methods for various types of optical buffers. A practical and challenging issue of the constructions of optical buffers that has not been addressed before is on the fault-tolerant capability of such constructions. In this paper, we focus on the constructions of fault-tolerant optical 2-... View full abstract»

• ### Using Orthogonal and Quasi-Orthogonal Designs in Wireless Relay Networks

Publication Year: 2007, Page(s):4106 - 4118
Cited by:  Papers (200)  |  Patents (3)
| | PDF (390 KB) | HTML

Distributed space-time coding was proposed to achieve cooperative diversity in wireless relay networks without channel information at the relays. Using this scheme, antennas of the distributive relays work as transmit antennas of the sender and generate a space-time code at the receiver. It achieves the maximal diversity when the transmit power is infinitely large. This paper is on the design of p... View full abstract»

• ### Limited-Shift-Full-Rank Matrices With Applications in Asynchronous Cooperative Communications

Publication Year: 2007, Page(s):4119 - 4126
Cited by:  Papers (23)
| | PDF (239 KB) | HTML

Shift-full-rank (SFR) matrices are matrices that have full row rank no matter how their rows are shifted. SFR matrices have been used lately as generator matrices for a family of space-time trellis codes to achieve full diversity in asynchronous cooperative communications, where the numbers of columns of the SFR matrices correspond to the memory sizes of the trellis codes. A systematic constructio... View full abstract»

• ### The Effect of Fading, Channel Inversion, and Threshold Scheduling on <emphasis>Ad Hoc</emphasis> Networks

Publication Year: 2007, Page(s):4127 - 4149
Cited by:  Papers (203)
| | PDF (712 KB) | HTML

This paper addresses three issues in the field of ad hoc network capacity: the impact of (i) channel fading, (ii) channel inversion power control, and (iii) threshold-based scheduling on capacity. Channel inversion and threshold scheduling may be viewed as simple ways to exploit channel state information (CSI) without requiring cooperation across transmitters. We use the transmission capacity (TC)... View full abstract»

• ### Diversity–Multiplexing Tradeoff of Asynchronous Cooperative Diversity in Wireless Networks

Publication Year: 2007, Page(s):4150 - 4172
Cited by:  Papers (56)
| | PDF (608 KB) | HTML

Synchronization of relay nodes is an important and critical issue in exploiting cooperative diversity in wireless networks. In this paper, two asynchronous cooperative diversity schemes are proposed, namely, distributed delay diversity and asynchronous space-time coded cooperative diversity schemes. In terms of the overall diversity-multiplexing (DM) tradeoff function, we show that the proposed in... View full abstract»

• ### Asymptotic Performance of MMSE Receivers for Large Systems Using Random Matrix Theory

Publication Year: 2007, Page(s):4173 - 4190
Cited by:  Papers (40)  |  Patents (3)
| | PDF (768 KB) | HTML

Random matrix theory is used to derive the limit and asymptotic distribution of signal-to-interference-plus-noise ratio (SIR) for a class of suboptimal minimum mean-square-error (MMSE) receivers applied to large random systems with unequal-power users. We prove that the limiting SIR converges to a deterministic value when K and N go to infinity with lim K/N = y being a positive constant, where K i... View full abstract»

• ### Asymptotic Performance of a Censoring Sensor Network

Publication Year: 2007, Page(s):4191 - 4209
Cited by:  Papers (37)
| | PDF (611 KB) | HTML

We consider the problem of decentralized binary detection in a sensor network where the sensors have access to side information that affects the statistics of their measurements, or reflects the quality of the available channel to a fusion center. Sensors can decide whether or not to make a measurement and transmit a message to the fusion center ("censoring"), and also have a choice of the mapping... View full abstract»

• ### On Bounds for$E$-Capacity of DMC

Publication Year: 2007, Page(s):4210 - 4220
Cited by:  Papers (4)
| | PDF (276 KB) | HTML

In this paper, we survey the concept of theE-capacity as a generalization to the Shannon's capacity of a channel and as an counterpart to the Shannon's reliability function. Random coding, expurgated and sphere packing bounds are derived by the method of types and by the method of graph decomposition forE-capacity of discrete memoryless channel (DMC). Three decoding rules are conside... 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