id
stringlengths 9
10
| submitter
stringlengths 2
52
⌀ | authors
stringlengths 4
6.51k
| title
stringlengths 4
246
| comments
stringlengths 1
523
⌀ | journal-ref
stringlengths 4
345
⌀ | doi
stringlengths 11
120
⌀ | report-no
stringlengths 2
243
⌀ | categories
stringlengths 5
98
| license
stringclasses 9
values | abstract
stringlengths 33
3.33k
| versions
list | update_date
timestamp[s] | authors_parsed
list | prediction
stringclasses 1
value | probability
float64 0.95
1
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0708.0964
|
Colm \'O D\'unlaing
|
Colm O Dunlaing
|
Nodally 3-connected planar graphs and convex combination mappings
|
27 pages Latex, 11 postscript figures
| null | null |
TCDMATH 06-16
|
cs.CG
| null |
A convex combination mapping of a planar graph is a plane mapping in which
the external vertices are mapped to the corners of a convex polygon and every
internal vertex is a proper weighted average of its neighbours. If a planar
graph is nodally 3-connected or triangulated then every such mapping is an
embedding (Tutte, Floater).
We give a simple characterisation of nodally 3-connected planar graphs, and
generalise the above result to any planar graph which admits any convex
embedding.
|
[
{
"version": "v1",
"created": "Tue, 7 Aug 2007 14:32:38 GMT"
}
] | 2007-08-08T00:00:00 |
[
[
"Dunlaing",
"Colm O",
""
]
] |
new_dataset
| 0.988245 |
0708.0604
|
L.T. Handoko
|
T.B. Waluyo and L.T. Handoko
|
Introducing OPTO : Portal for Optical Communities in Indonesia
|
3 pages, Proceeding of the 2nd International Conf. on Optics and
Laser Applications 2007
| null | null |
FISIKALIPI-07006
|
cs.CY
| null |
Since January 1, 2005 we have launched "OPTO" Portal, a website dedicated to
optical communities in Indonesia. The address of this portal is
http://www.opto.lipi.go.id and is self-supporting managed and not for
commercial purposes. Our aims in launching this portal are to benefit Internet
facility in increasing the communities' scientific activity; to provide an
online reference in Indonesian language for optics-based science and technology
subjects; as well as to pioneer the communities' online activities with real
impacts and benefits for our society. We will describe in the paper the
features of this portal that can be utilized by all individuals or members of
optical communities to store and share information and to build networks or
partnership as well. We realized that this portal is still not popular and most
of our aims are still not reached. This conference should be a good place for
all of us to collaborate to properly utilize this portal for the advantages to
the optical communities in Indonesia and our society at large.
|
[
{
"version": "v1",
"created": "Sat, 4 Aug 2007 05:16:10 GMT"
}
] | 2007-08-07T00:00:00 |
[
[
"Waluyo",
"T. B.",
""
],
[
"Handoko",
"L. T.",
""
]
] |
new_dataset
| 0.995244 |
0708.0624
|
Matthias Brust R.
|
Christian Hutter, Matthias R. Brust, Steffen Rothkugel
|
ADS-Directory Services for Mobile Ad-Hoc Networks Based on an
Information Market Model
|
9 pages, in the 1st International Workshop on Ubiquitous Computing
(IWUC-2004) held in conjunction with the 6th International Conference on
Enterprise Information Systems (ICEIS 2004)
| null | null | null |
cs.NI cs.DC
| null |
Ubiquitous computing based on small mobile devices using wireless
communication links is becoming very attractive. The computational power and
storage capacities provided allow the execution of sophisticated applications.
Due to the fact that sharing of information is a central problem for
distributed applications, the development of self organizing middleware
services providing high level interfaces for information managing is essential.
ADS is a directory service for mobile ad-hoc networks dealing with local and
nearby information as well as providing access to distant information. The
approach discussed throughout this paper is based upon the concept of
information markets.
|
[
{
"version": "v1",
"created": "Sat, 4 Aug 2007 13:21:55 GMT"
}
] | 2007-08-07T00:00:00 |
[
[
"Hutter",
"Christian",
""
],
[
"Brust",
"Matthias R.",
""
],
[
"Rothkugel",
"Steffen",
""
]
] |
new_dataset
| 0.981496 |
0707.4389
|
Sandrine Blazy
|
Andrew W. Appel (INRIA Rocquencourt), Sandrine Blazy (CEDRIC, INRIA
Rocquencourt)
|
Separation Logic for Small-step Cminor
|
Version courte du rapport de recherche RR-6138
|
Dans 20th Int. Conference on Theorem Proving in Higher Order
Logics (TPHOLs 2007) 4732 (2007) 5-21
| null | null |
cs.PL
| null |
Cminor is a mid-level imperative programming language; there are
proved-correct optimizing compilers from C to Cminor and from Cminor to machine
language. We have redesigned Cminor so that it is suitable for Hoare Logic
reasoning and we have designed a Separation Logic for Cminor. In this paper, we
give a small-step semantics (instead of the big-step of the proved-correct
compiler) that is motivated by the need to support future concurrent
extensions. We detail a machine-checked proof of soundness of our Separation
Logic. This is the first large-scale machine-checked proof of a Separation
Logic w.r.t. a small-step semantics. The work presented in this paper has been
carried out in the Coq proof assistant. It is a first step towards an
environment in which concurrent Cminor programs can be verified using
Separation Logic and also compiled by a proved-correct compiler with formal
end-to-end correctness guarantees.
|
[
{
"version": "v1",
"created": "Mon, 30 Jul 2007 12:09:16 GMT"
}
] | 2007-07-31T00:00:00 |
[
[
"Appel",
"Andrew W.",
"",
"INRIA Rocquencourt"
],
[
"Blazy",
"Sandrine",
"",
"CEDRIC, INRIA\n Rocquencourt"
]
] |
new_dataset
| 0.990894 |
0707.3717
|
Yann Busnel
|
Yann Busnel (IRISA, DIT), Marin Bertier (IRISA), Eric Fleury (INRIA
Rh\^one-Alpes), Anne-Marie Kermarrec (IRISA)
|
GCP: Gossip-based Code Propagation for Large-scale Mobile Wireless
Sensor Networks
| null | null | null | null |
cs.NI
| null |
Wireless sensor networks (WSN) have recently received an increasing interest.
They are now expected to be deployed for long periods of time, thus requiring
software updates. Updating the software code automatically on a huge number of
sensors is a tremendous task, as ''by hand'' updates can obviously not be
considered, especially when all participating sensors are embedded on mobile
entities. In this paper, we investigate an approach to automatically update
software in mobile sensor-based application when no localization mechanism is
available. We leverage the peer-to-peer cooperation paradigm to achieve a good
trade-off between reliability and scalability of code propagation. More
specifically, we present the design and evaluation of GCP ({\emph Gossip-based
Code Propagation}), a distributed software update algorithm for mobile wireless
sensor networks. GCP relies on two different mechanisms (piggy-backing and
forwarding control) to improve significantly the load balance without
sacrificing on the propagation speed. We compare GCP against traditional
dissemination approaches. Simulation results based on both synthetic and
realistic workloads show that GCP achieves a good convergence speed while
balancing the load evenly between sensors.
|
[
{
"version": "v1",
"created": "Wed, 25 Jul 2007 11:52:09 GMT"
},
{
"version": "v2",
"created": "Mon, 30 Jul 2007 12:21:45 GMT"
}
] | 2007-07-30T00:00:00 |
[
[
"Busnel",
"Yann",
"",
"IRISA, DIT"
],
[
"Bertier",
"Marin",
"",
"IRISA"
],
[
"Fleury",
"Eric",
"",
"INRIA\n Rhône-Alpes"
],
[
"Kermarrec",
"Anne-Marie",
"",
"IRISA"
]
] |
new_dataset
| 0.985178 |
0707.3507
|
Damien Chablat
|
Daniel Kanaan (IRCCyN), Philippe Wenger (IRCCyN), Damien Chablat
(IRCCyN)
|
Workspace and Kinematic Analysis of the VERNE machine
| null |
Dans International Conference on Advanced Intelligent Mechatronics
- AIM, Z\"urich : Suisse (09/2007)
| null | null |
cs.RO
| null |
This paper describes the workspace and the inverse and direct kinematic
analysis of the VERNE machine, a serial/parallel 5-axis machine tool designed
by Fatronik for IRCCyN. This machine is composed of a three-degree-of-freedom
(DOF) parallel module and a two-DOF serial tilting table. The parallel module
consists of a moving platform that is connected to a fixed base by three
non-identical legs. This feature involves (i) a simultaneous combination of
rotation and translation for the moving platform, which is balanced by the
tilting table and (ii) workspace whose shape and volume vary as a function of
the tool length. This paper summarizes results obtained in the context of the
European projects NEXT ("Next Generation of Productions Systems").
|
[
{
"version": "v1",
"created": "Tue, 24 Jul 2007 09:13:22 GMT"
}
] | 2007-07-25T00:00:00 |
[
[
"Kanaan",
"Daniel",
"",
"IRCCyN"
],
[
"Wenger",
"Philippe",
"",
"IRCCyN"
],
[
"Chablat",
"Damien",
"",
"IRCCyN"
]
] |
new_dataset
| 0.990636 |
0707.3550
|
Damien Chablat
|
Damien Chablat (IRCCyN), Philippe Wenger (IRCCyN)
|
A Six Degree-Of-Freedom Haptic Device Based On The Orthoglide And A
Hybrid Agile Eye
| null |
Dans Proceedings of IDETC 2006: 30th Mechanisms & Robotics
Conference (MR) - IDETC, Philadelphie : \'Etats-Unis d'Am\'erique (2006)
| null | null |
cs.RO
| null |
This paper is devoted to the kinematic design of a new six degree-of-freedom
haptic device using two parallel mechanisms. The first one, called orthoglide,
provides the translation motions and the second one, called agile eye, produces
the rotational motions. These two motions are decoupled to simplify the direct
and inverse kinematics, as it is needed for real-time control. To reduce the
inertial load, the motors are fixed on the base and a transmission with two
universal joints is used to transmit the rotational motions from the base to
the end-effector. Two alternative wrists are proposed (i), the agile eye with
three degrees of freedom or (ii) a hybrid wrist made by the assembly of a
two-dof agile eye with a rotary motor. The last one is optimized to increase
its stiffness and to decrease the number of moving parts.
|
[
{
"version": "v1",
"created": "Tue, 24 Jul 2007 13:42:08 GMT"
}
] | 2007-07-25T00:00:00 |
[
[
"Chablat",
"Damien",
"",
"IRCCyN"
],
[
"Wenger",
"Philippe",
"",
"IRCCyN"
]
] |
new_dataset
| 0.992688 |
0707.3564
|
Damien Chablat
|
Damien Chablat (IRCCyN), Philippe Wenger (IRCCyN)
|
A New Six Degree-of-Freedom Haptic Device based on the Orthoglide and
the Agile Eye
| null |
Dans Proceedings of Virtual Concept 2005 - Virtual Concept, France
(11/2005)
| null | null |
cs.RO
| null |
The aim of this paper is to present a new six degree-of-freedom (dof) haptic
device using two parallel mechanisms. The first one, called orthoglide,
provides the translation motions and the second one produces the rotational
motions. These two motions are decoupled to simplify the direct and inverse
kinematics, as it is needed for real-times control. To reduce the inertial
load, the motors are fixed on the base and a transmission with two universal
joints is used to transmit the rotational motions from the base to the
end-effector. The main feature of the orthoglide and of the agile eye mechanism
is the existence of an isotropic configuration. The length of the legs and the
range limits of the orthoglide are optimized to have homogeneous performance
throughout the Cartesian workspace, which has a nearly cubic workspace. These
properties permit to have a high stiffness throughout the workspace and
workspace limits that are easily understandable by the user.
|
[
{
"version": "v1",
"created": "Tue, 24 Jul 2007 14:29:41 GMT"
}
] | 2007-07-25T00:00:00 |
[
[
"Chablat",
"Damien",
"",
"IRCCyN"
],
[
"Wenger",
"Philippe",
"",
"IRCCyN"
]
] |
new_dataset
| 0.997159 |
0707.2998
|
Patrick Murphy
|
Patrick Murphy, Ashutosh Sabharwal and Behnaam Aazhang
|
Building a Cooperative Communications System
| null | null | null | null |
cs.IT math.IT
| null |
In this paper, we present the results from over-the-air experiments of a
complete implementation of an amplify and forward cooperative communications
system. Our custom OFDM-based physical layer uses a distributed version of the
Alamouti block code, where the relay sends one branch of Alamouti encoded
symbols. First we show analytically and experimentally that amplify and forward
protocols are unaffected by carrier frequency offsets at the relay. This result
allows us to use a conventional Alamouti receiver without change for the
distributed relay system. Our full system implementation shows gains up to
5.5dB in peak power constrained networks. Thus, we can conclusively state that
even the simplest form of relaying can lead to significant gains in practical
implementations.
|
[
{
"version": "v1",
"created": "Fri, 20 Jul 2007 05:38:07 GMT"
}
] | 2007-07-23T00:00:00 |
[
[
"Murphy",
"Patrick",
""
],
[
"Sabharwal",
"Ashutosh",
""
],
[
"Aazhang",
"Behnaam",
""
]
] |
new_dataset
| 0.993226 |
0707.2841
|
Damien Chablat
|
Damien Chablat (IRCCyN), Philippe D\'epinc\'e, Eric No\"el,
Peer-Oliver Woelk (IFW)
|
The Virtual Manufacturing concept: Scope, Socio-Economic Aspects and
Future Trends
| null |
Design Engineering Technical Conferences (09/2004) 1-6
| null | null |
cs.RO
| null |
The research area "Virtual Manufacturing (VM)'' is the use of information
technology and computer simulation to model real world manufacturing processes
for the purpose of analysing and understanding them. As automation technologies
such as CAD/CAM have substantially shortened the time required to design
products, Virtual Manufacturing will have a similar effect on the manufacturing
phase thanks to the modelling, simulation and optimisation of the product and
the processes involved in its fabrication. After a description of Virtual
Manufacturing (definitions and scope), we present some socio-economic factors
of VM and finaly some "hot topics'' for the future are proposed.
|
[
{
"version": "v1",
"created": "Thu, 19 Jul 2007 07:15:53 GMT"
}
] | 2007-07-20T00:00:00 |
[
[
"Chablat",
"Damien",
"",
"IRCCyN"
],
[
"Dépincé",
"Philippe",
"",
"IFW"
],
[
"Noël",
"Eric",
"",
"IFW"
],
[
"Woelk",
"Peer-Oliver",
"",
"IFW"
]
] |
new_dataset
| 0.974576 |
0707.2886
|
Laurent Romary
|
Laurent Romary (MPDL)
|
OA@MPS - a colourful view
| null |
Zeitschrift f\"ur Bibliothekswesen und Bibliographie (15/08/2007)
7 pages
| null | null |
cs.DL
| null |
The open access agenda of the Max Planck Society, initiator of the Berlin
Declaration, envisions the support of both the green way and the golden way to
open access. For the implementation of the green way the Max Planck Society
through its newly established unit (Max Planck Digital Library) follows the
idea of providing a centralized technical platform for publications and a local
support for editorial issues. With regard to the golden way, the Max Planck
Society fosters the development of open access publication models and
experiments new publishing concepts like the Living Reviews journals.
|
[
{
"version": "v1",
"created": "Thu, 19 Jul 2007 12:30:42 GMT"
}
] | 2007-07-20T00:00:00 |
[
[
"Romary",
"Laurent",
"",
"MPDL"
]
] |
new_dataset
| 0.981942 |
0707.2921
|
Andrea Pacifici
|
Alessandro Agnetis, Enrico Grande, Pitu B. Mirchandani, Andrea
Pacifici
|
Covering a line segment with variable radius discs
|
21 pages, 2 figures
| null | null | null |
cs.DM cs.NA
| null |
The paper addresses the problem of locating sensors with a circular field of
view so that a given line segment is under full surveillance, which is termed
as the Disc Covering Problem on a Line. The cost of each sensor includes a
fixed component, and a variable component that is proportional to the
field-of-view area. When only one type of sensor or, in general, one type of
disc, is available, then a simple polynomial algorithm solves the problem. When
there are different types of sensors in terms of fixed and variable costs, the
problem becomes NP-hard. A branch-and-bound algorithm as well as an efficient
heuristic are developed. The heuristic very often obtains the optimal solution
as shown in extensive computational testing.
|
[
{
"version": "v1",
"created": "Thu, 19 Jul 2007 14:59:47 GMT"
}
] | 2007-07-20T00:00:00 |
[
[
"Agnetis",
"Alessandro",
""
],
[
"Grande",
"Enrico",
""
],
[
"Mirchandani",
"Pitu B.",
""
],
[
"Pacifici",
"Andrea",
""
]
] |
new_dataset
| 0.997914 |
0707.0562
|
Stefan G\"oller
|
Stefan G\"oller and Dirk Nowotka
|
On a Non-Context-Free Extension of PDL
| null | null | null | null |
cs.LO
| null |
Over the last 25 years, a lot of work has been done on seeking for decidable
non-regular extensions of Propositional Dynamic Logic (PDL). Only recently, an
expressive extension of PDL, allowing visibly pushdown automata (VPAs) as a
formalism to describe programs, was introduced and proven to have a
satisfiability problem complete for deterministic double exponential time.
Lately, the VPA formalism was extended to so called k-phase multi-stack visibly
pushdown automata (k-MVPAs). Similarly to VPAs, it has been shown that the
language of k-MVPAs have desirable effective closure properties and that the
emptiness problem is decidable. On the occasion of introducing k-MVPAs, it has
been asked whether the extension of PDL with k-MVPAs still leads to a decidable
logic. This question is answered negatively here. We prove that already for the
extension of PDL with 2-phase MVPAs with two stacks satisfiability becomes
\Sigma_1^1-complete.
|
[
{
"version": "v1",
"created": "Wed, 4 Jul 2007 09:33:21 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Jul 2007 10:11:01 GMT"
}
] | 2007-07-18T00:00:00 |
[
[
"Göller",
"Stefan",
""
],
[
"Nowotka",
"Dirk",
""
]
] |
new_dataset
| 0.959141 |
0707.2160
|
Seth Pettie
|
Seth Pettie
|
Splay Trees, Davenport-Schinzel Sequences, and the Deque Conjecture
| null | null | null | null |
cs.DS
| null |
We introduce a new technique to bound the asymptotic performance of splay
trees. The basic idea is to transcribe, in an indirect fashion, the rotations
performed by the splay tree as a Davenport-Schinzel sequence S, none of whose
subsequences are isomorphic to fixed forbidden subsequence. We direct this
technique towards Tarjan's deque conjecture and prove that n deque operations
require O(n alpha^*(n)) time, where alpha^*(n) is the minimum number of
applications of the inverse-Ackermann function mapping n to a constant. We are
optimistic that this approach could be directed towards other open conjectures
on splay trees such as the traversal and split conjectures.
|
[
{
"version": "v1",
"created": "Sat, 14 Jul 2007 16:38:08 GMT"
}
] | 2007-07-17T00:00:00 |
[
[
"Pettie",
"Seth",
""
]
] |
new_dataset
| 0.99779 |
0707.2270
|
Damien Chablat
|
Damien Chablat (IRCCyN), Philippe Wenger (IRCCyN)
|
Design of a Spherical Wrist with Parallel Architecture: Application to
Vertebrae of an Eel Robot
| null |
Proc. IEEE Int. Conf. Rob. and Automation (04/2005) 1-6
| null | null |
cs.RO
| null |
The design of a spherical wrist with parallel architecture is the object of
this article. This study is part of a larger project, which aims to design and
to build an eel robot for inspection of immersed piping. The kinematic analysis
of the mechanism is presented first to characterize the singular configurations
as well as the isotropic configurations. We add the design constraints related
to the application, such as (i) the compactness of the mechanism, (ii) the
symmetry of the elements in order to ensure static and dynamic balance and
(iii) the possibility of the mechanism to fill the elliptic form of the ell
sections.
|
[
{
"version": "v1",
"created": "Mon, 16 Jul 2007 07:41:16 GMT"
}
] | 2007-07-17T00:00:00 |
[
[
"Chablat",
"Damien",
"",
"IRCCyN"
],
[
"Wenger",
"Philippe",
"",
"IRCCyN"
]
] |
new_dataset
| 0.995075 |
0707.2027
|
Damien Chablat
|
Philippe Wenger (IRCCyN), Damien Chablat (IRCCyN)
|
Workspace and Assembly modes in Fully-Parallel Manipulators : A
Descriptive Study
| null |
Advances in Robot Kinematics and Computational Geometry (1998)
117-126
| null | null |
cs.RO
| null |
The goal of this paper is to explain, using a typical example, the
distribution of the different assembly modes in the workspace and their
effective role in the execution of trajectories. The singular and non-singular
changes of assembly mode are described and compared to each other. The
non-singular change of assembly mode is more deeply analysed and discussed in
the context of trajectory planning. In particular, it is shown that, according
to the location of the initial and final configurations with respect to the
uniqueness domains in the workspace, there are three different cases to
consider before planning a linking trajectory.
|
[
{
"version": "v1",
"created": "Fri, 13 Jul 2007 15:04:13 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Wenger",
"Philippe",
"",
"IRCCyN"
],
[
"Chablat",
"Damien",
"",
"IRCCyN"
]
] |
new_dataset
| 0.996538 |
cs/0406001
|
Kim-Chi Nguyen
|
Kim-Chi Nguyen, Gilles Van Assche and Nicolas J. Cerf
|
Side-Information Coding with Turbo Codes and its Application to Quantum
Key Distribution
|
3 pages, submitted to ISITA 2004
| null | null | null |
cs.IT cs.CR math.IT quant-ph
| null |
Turbo coding is a powerful class of forward error correcting codes, which can
achieve performances close to the Shannon limit. The turbo principle can be
applied to the problem of side-information source coding, and we investigate
here its application to the reconciliation problem occurring in a
continuous-variable quantum key distribution protocol.
|
[
{
"version": "v1",
"created": "Tue, 1 Jun 2004 09:26:00 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Nguyen",
"Kim-Chi",
""
],
[
"Van Assche",
"Gilles",
""
],
[
"Cerf",
"Nicolas J.",
""
]
] |
new_dataset
| 0.9978 |
cs/0408038
|
G. David Forney
|
G. David Forney Jr. and Mitchell D. Trott
|
The Dynamics of Group Codes: Dual Abelian Group Codes and Systems
|
30 pages, 11 figures. To appear in IEEE Trans. Inform. Theory, 2004
|
IEEE Trans. Inform. Theory, vol. 50, pp. 2935-2965, Dec. 2004.
|
10.1109/TIT.2004.838340
| null |
cs.IT math.IT
| null |
Fundamental results concerning the dynamics of abelian group codes
(behaviors) and their duals are developed. Duals of sequence spaces over
locally compact abelian groups may be defined via Pontryagin duality; dual
group codes are orthogonal subgroups of dual sequence spaces. The dual of a
complete code or system is finite, and the dual of a Laurent code or system is
(anti-)Laurent. If C and C^\perp are dual codes, then the state spaces of C act
as the character groups of the state spaces of C^\perp. The controllability
properties of C are the observability properties of C^\perp. In particular, C
is (strongly) controllable if and only if C^\perp is (strongly) observable, and
the controller memory of C is the observer memory of C^\perp. The controller
granules of C act as the character groups of the observer granules of C^\perp.
Examples of minimal observer-form encoder and syndrome-former constructions are
given. Finally, every observer granule of C is an "end-around" controller
granule of C.
|
[
{
"version": "v1",
"created": "Mon, 16 Aug 2004 16:05:06 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Forney",
"G. David",
"Jr."
],
[
"Trott",
"Mitchell D.",
""
]
] |
new_dataset
| 0.999156 |
cs/0408066
|
Madhu Sudan
|
Eli Ben-Sasson and Madhu Sudan
|
Robust Locally Testable Codes and Products of Codes
| null | null | null | null |
cs.IT cs.CC math.IT
| null |
We continue the investigation of locally testable codes, i.e.,
error-correcting codes for whom membership of a given word in the code can be
tested probabilistically by examining it in very few locations. We give two
general results on local testability: First, motivated by the recently proposed
notion of {\em robust} probabilistically checkable proofs, we introduce the
notion of {\em robust} local testability of codes. We relate this notion to a
product of codes introduced by Tanner, and show a very simple composition lemma
for this notion. Next, we show that codes built by tensor products can be
tested robustly and somewhat locally, by applying a variant of a test and proof
technique introduced by Raz and Safra in the context of testing low-degree
multivariate polynomials (which are a special case of tensor codes).
Combining these two results gives us a generic construction of codes of
inverse polynomial rate, that are testable with poly-logarithmically many
queries. We note these locally testable tensor codes can be obtained from {\em
any} linear error correcting code with good distance. Previous results on local
testability, albeit much stronger quantitatively, rely heavily on algebraic
properties of the underlying codes.
|
[
{
"version": "v1",
"created": "Mon, 30 Aug 2004 16:36:38 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Ben-Sasson",
"Eli",
""
],
[
"Sudan",
"Madhu",
""
]
] |
new_dataset
| 0.999597 |
cs/0502024
|
Robin Horan
|
R.Horan, C.Tjhai, M.Tomlinson, M.Ambroze, M.Ahmed
|
Idempotents, Mattson-Solomon Polynomials and Binary LDPC codes
|
9 pages, 3 figures
| null | null | null |
cs.IT math.IT
| null |
We show how to construct an algorithm to search for binary idempotents which
may be used to construct binary LDPC codes. The algorithm, which allows control
of the key properties of sparseness, code rate and minimum distance, is
constructed in the Mattson-Solomon domain. Some of the new codes, found by
using this technique, are displayed.
|
[
{
"version": "v1",
"created": "Fri, 4 Feb 2005 10:08:07 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Horan",
"R.",
""
],
[
"Tjhai",
"C.",
""
],
[
"Tomlinson",
"M.",
""
],
[
"Ambroze",
"M.",
""
],
[
"Ahmed",
"M.",
""
]
] |
new_dataset
| 0.996426 |
cs/0502033
|
Ralf Koetter
|
Ralf Koetter, Wen-Ching W. Li, Pascal O. Vontobel, Judy L. Walker
|
Pseudo-Codewords of Cycle Codes via Zeta Functions
|
Presented at Information Theory Workshop (ITW), San Antonio, TX, 2004
| null | null | null |
cs.IT math.IT
| null |
Cycle codes are a special case of low-density parity-check (LDPC) codes and
as such can be decoded using an iterative message-passing decoding algorithm on
the associated Tanner graph. The existence of pseudo-codewords is known to
cause the decoding algorithm to fail in certain instances. In this paper, we
draw a connection between pseudo-codewords of cycle codes and the so-called
edge zeta function of the associated normal graph and show how the Newton
polyhedron of the zeta function equals the fundamental cone of the code, which
plays a crucial role in characterizing the performance of iterative decoding
algorithms.
|
[
{
"version": "v1",
"created": "Sun, 6 Feb 2005 03:26:37 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Koetter",
"Ralf",
""
],
[
"Li",
"Wen-Ching W.",
""
],
[
"Vontobel",
"Pascal O.",
""
],
[
"Walker",
"Judy L.",
""
]
] |
new_dataset
| 0.99649 |
cs/0503085
|
Travis Gagie
|
Travis Gagie
|
Dynamic Shannon Coding
|
6 pages; conference version presented at ESA 2004; journal version
submitted to IEEE Transactions on Information Theory
| null | null | null |
cs.IT math.IT
| null |
We present a new algorithm for dynamic prefix-free coding, based on Shannon
coding. We give a simple analysis and prove a better upper bound on the length
of the encoding produced than the corresponding bound for dynamic Huffman
coding. We show how our algorithm can be modified for efficient
length-restricted coding, alphabetic coding and coding with unequal letter
costs.
|
[
{
"version": "v1",
"created": "Wed, 30 Mar 2005 13:51:46 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Gagie",
"Travis",
""
]
] |
new_dataset
| 0.998744 |
cs/0504085
|
Vignesh Sethuraman
|
Vignesh Sethuraman and Bruce Hajek
|
Capacity per Unit Energy of Fading Channels with a Peak Constraint
|
Journal version of paper presented in ISIT 2003 - now accepted for
publication in IEEE Transactions on Information Theory
| null |
10.1109/TIT.2005.853329
| null |
cs.IT math.IT
| null |
A discrete-time single-user scalar channel with temporally correlated
Rayleigh fading is analyzed. There is no side information at the transmitter or
the receiver. A simple expression is given for the capacity per unit energy, in
the presence of a peak constraint. The simple formula of Verdu for capacity per
unit cost is adapted to a channel with memory, and is used in the proof. In
addition to bounding the capacity of a channel with correlated fading, the
result gives some insight into the relationship between the correlation in the
fading process and the channel capacity. The results are extended to a channel
with side information, showing that the capacity per unit energy is one nat per
Joule, independently of the peak power constraint.
A continuous-time version of the model is also considered. The capacity per
unit energy subject to a peak constraint (but no bandwidth constraint) is given
by an expression similar to that for discrete time, and is evaluated for
Gauss-Markov and Clarke fading channels.
|
[
{
"version": "v1",
"created": "Mon, 18 Apr 2005 16:29:14 GMT"
},
{
"version": "v2",
"created": "Sat, 11 Jun 2005 01:36:55 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Sethuraman",
"Vignesh",
""
],
[
"Hajek",
"Bruce",
""
]
] |
new_dataset
| 0.975311 |
cs/0504102
|
Lars Eirik Danielsen
|
Lars Eirik Danielsen (1), Matthew G. Parker (1) ((1) University of
Bergen)
|
Spectral Orbits and Peak-to-Average Power Ratio of Boolean Functions
with respect to the {I,H,N}^n Transform
|
Presented at Sequences and Their Applications, SETA'04, Seoul, South
Korea, October 2004. 17 pages, 10 figures
|
In Sequences and Their Applications -- SETA 2004, edited by T.
Helleseth, D. Sarwate, H.-Y. Song, and K. Yang, Lecture Notes in Comput.
Sci., volume 3486, pp. 373--388, Springer-Verlag, Berlin, May 2005.
|
10.1007/11423461_28
| null |
cs.IT math.IT
| null |
We enumerate the inequivalent self-dual additive codes over GF(4) of
blocklength n, thereby extending the sequence A090899 in The On-Line
Encyclopedia of Integer Sequences from n = 9 to n = 12. These codes have a
well-known interpretation as quantum codes. They can also be represented by
graphs, where a simple graph operation generates the orbits of equivalent
codes. We highlight the regularity and structure of some graphs that correspond
to codes with high distance. The codes can also be interpreted as quadratic
Boolean functions, where inequivalence takes on a spectral meaning. In this
context we define PAR_IHN, peak-to-average power ratio with respect to the
{I,H,N}^n transform set. We prove that PAR_IHN of a Boolean function is
equivalent to the the size of the maximum independent set over the associated
orbit of graphs. Finally we propose a construction technique to generate
Boolean functions with low PAR_IHN and algebraic degree higher than 2.
|
[
{
"version": "v1",
"created": "Mon, 25 Apr 2005 11:32:25 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Danielsen",
"Lars Eirik",
""
],
[
"Parker",
"Matthew G.",
""
]
] |
new_dataset
| 0.99315 |
cs/0505054
|
Mostafa El-Khamy
|
Mostafa El-Khamy and Robert J. McEliece
|
The Partition Weight Enumerator of MDS Codes and its Applications
|
This is a five page conference version of the paper which was
accepted by ISIT 2005. For more information, please contact the authors
| null | null | null |
cs.IT math.IT
| null |
A closed form formula of the partition weight enumerator of maximum distance
separable (MDS) codes is derived for an arbitrary number of partitions. Using
this result, some properties of MDS codes are discussed. The results are
extended for the average binary image of MDS codes in finite fields of
characteristic two. As an application, we study the multiuser error probability
of Reed Solomon codes.
|
[
{
"version": "v1",
"created": "Sat, 21 May 2005 01:21:27 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"El-Khamy",
"Mostafa",
""
],
[
"McEliece",
"Robert J.",
""
]
] |
new_dataset
| 0.999168 |
cs/0508035
|
Irina Naydenova
|
Irina Naydenova, Torleiv Klove
|
Codes for error detection, good or not good
|
To appear in the proceedings of the 2005 IEEE International Symposium
on Information Theory, Adelaide, Australia, September 4-9, 2005
| null | null | null |
cs.IT math.IT
| null |
Linear codes for error detection on a q-ary symmetric channel are studied. It
is shown that for given dimension k and minimum distance d, there exists a
value \mu(d,k) such that if C is a code of length n >= \mu(d,k), then neither C
nor its dual are good for error detection. For d >> k or k << d good
approximations for \mu(d,k) are given. A generalization to non-linear codes is
also given.
|
[
{
"version": "v1",
"created": "Thu, 4 Aug 2005 12:48:03 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Naydenova",
"Irina",
""
],
[
"Klove",
"Torleiv",
""
]
] |
new_dataset
| 0.953854 |
cs/0509006
|
Jean-Claude Belfiore
|
Sheng Yang and Jean-Claude Belfiore
|
Optimal space-time codes for the MIMO amplify-and-forward cooperative
channel
|
submitted to IEEE Transactions on Information Theory, revised version
| null | null | null |
cs.IT math.IT
| null |
In this work, we extend the non-orthogonal amplify-and-forward (NAF)
cooperative diversity scheme to the MIMO channel. A family of space-time block
codes for a half-duplex MIMO NAF fading cooperative channel with N relays is
constructed. The code construction is based on the non-vanishing determinant
criterion (NVD) and is shown to achieve the optimal diversity-multiplexing
tradeoff (DMT) of the channel. We provide a general explicit algebraic
construction, followed by some examples. In particular, in the single relay
case, it is proved that the Golden code and the 4x4 Perfect code are optimal
for the single-antenna and two-antenna case, respectively. Simulation results
reveal that a significant gain (up to 10dB) can be obtained with the proposed
codes, especially in the single-antenna case.
|
[
{
"version": "v1",
"created": "Fri, 2 Sep 2005 17:38:59 GMT"
},
{
"version": "v2",
"created": "Thu, 4 May 2006 07:54:33 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Yang",
"Sheng",
""
],
[
"Belfiore",
"Jean-Claude",
""
]
] |
new_dataset
| 0.987906 |
cs/0510043
|
Pascal Vontobel
|
Pascal O. Vontobel, Roxana Smarandache
|
On Minimal Pseudo-Codewords of Tanner Graphs from Projective Planes
|
This paper is a slightly reformulated version of the paper that
appeared in the proceedings of the 43rd Allerton Conference on
Communications, Control, and Computing, Allerton House, Monticello, Illinois,
USA, Sept. 28-30, 2005
|
Proc. 43rd Allerton Conference on Communications, Control, and
Computing, Allerton House, Monticello, Illinois, USA, Sept. 28-30, 2005
| null | null |
cs.IT cs.DM math.IT
| null |
We would like to better understand the fundamental cone of Tanner graphs
derived from finite projective planes. Towards this goal, we discuss bounds on
the AWGNC and BSC pseudo-weight of minimal pseudo-codewords of such Tanner
graphs, on one hand, and study the structure of minimal pseudo-codewords, on
the other.
|
[
{
"version": "v1",
"created": "Sat, 15 Oct 2005 23:51:52 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Vontobel",
"Pascal O.",
""
],
[
"Smarandache",
"Roxana",
""
]
] |
new_dataset
| 0.996915 |
cs/0601095
|
Mostafa El-Khamy
|
Mostafa El-Khamy and Roberto Garello
|
On the Weight Enumerator and the Maximum Likelihood Performance of
Linear Product Codes
|
26 pages, 10 figures, submitted to IEEE transactions in December 2005
| null | null | null |
cs.IT math.IT
| null |
Product codes are widely used in data-storage, optical and wireless
applications. Their analytical performance evaluation usually relies on the
truncated union bound, which provides a low error rate approximation based on
the minimum distance term only. In fact, the complete weight enumerator of most
product codes remains unknown. In this paper, concatenated representations are
introduced and applied to compute the complete average enumerators of arbitrary
product codes over a field Fq. The split weight enumerators of some important
constituent codes (Hamming, Reed-Solomon) are studied and used in the analysis.
The average binary weight enumerators of Reed Solomon product codes are also
derived. Numerical results showing the enumerator behavior are presented. By
using the complete enumerators, Poltyrev bounds on the maximum likelihood
performance, holding at both high and low error rates, are finally shown and
compared against truncated union bounds and simulation results.
|
[
{
"version": "v1",
"created": "Mon, 23 Jan 2006 05:43:12 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"El-Khamy",
"Mostafa",
""
],
[
"Garello",
"Roberto",
""
]
] |
new_dataset
| 0.997604 |
cs/0602067
|
Michael Baer
|
Michael B. Baer
|
Renyi to Renyi -- Source Coding under Siege
|
5 pages, 1 figure, accepted to ISIT 2006
| null | null | null |
cs.IT cs.DS math.IT
| null |
A novel lossless source coding paradigm applies to problems of unreliable
lossless channels with low bit rates, in which a vital message needs to be
transmitted prior to termination of communications. This paradigm can be
applied to Alfred Renyi's secondhand account of an ancient siege in which a spy
was sent to scout the enemy but was captured. After escaping, the spy returned
to his base in no condition to speak and unable to write. His commander asked
him questions that he could answer by nodding or shaking his head, and the
fortress was defended with this information. Renyi told this story with
reference to prefix coding, but maximizing probability of survival in the siege
scenario is distinct from yet related to the traditional source coding
objective of minimizing expected codeword length. Rather than finding a code
minimizing expected codeword length $\sum_{i=1}^n p(i) l(i)$, the siege problem
involves maximizing $\sum_{i=1}^n p(i) \theta^{l(i)}$ for a known $\theta \in
(0,1)$. When there are no restrictions on codewords, this problem can be solve
using a known generalization of Huffman coding. The optimal solution has coding
bounds which are functions of Renyi entropy; in addition to known bounds, new
bounds are derived here. The alphabetically constrained version of this problem
has applications in search trees and diagnostic testing. A novel dynamic
programming algorithm -- based upon the oldest known algorithm for the
traditional alphabetic problem -- optimizes this problem in $O(n^3)$ time and
$O(n^2)$ space, whereas two novel approximation algorithms can find a
suboptimal solution faster: one in linear time, the other in $O(n \log n)$.
Coding bounds for the alphabetic version of this problem are also presented.
|
[
{
"version": "v1",
"created": "Fri, 17 Feb 2006 23:40:26 GMT"
},
{
"version": "v2",
"created": "Mon, 22 May 2006 20:32:04 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Baer",
"Michael B.",
""
]
] |
new_dataset
| 0.990746 |
cs/0603124
|
Sheng Yang
|
Sheng Yang and Jean-Claude Belfiore
|
Diversity-Multiplexing Tradeoff of Double Scattering MIMO Channels
|
17 pages, 1 figure, submitted to IEEE trans. IT
| null | null | null |
cs.IT math.IT
| null |
It is well known that the presence of double scattering degrades the
performance of a MIMO channel, in terms of both the multiplexing gain and the
diversity gain. In this paper, a closed-form expression of the
diversity-multiplexing tradeoff (DMT) of double scattering MIMO channels is
obtained. It is shown that, for a channel with nT transmit antennas, nR receive
antennas and nS scatterers, the DMT only depends on the ordered version of the
triple (nT,nS,nR), for arbitrary nT, nS and nR. The condition under which the
double scattering channel has the same DMT as the single scattering channel is
also established.
|
[
{
"version": "v1",
"created": "Thu, 30 Mar 2006 17:45:59 GMT"
},
{
"version": "v2",
"created": "Fri, 31 Mar 2006 12:40:33 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Yang",
"Sheng",
""
],
[
"Belfiore",
"Jean-Claude",
""
]
] |
new_dataset
| 0.996301 |
cs/0604093
|
Jean-Claude Belfiore
|
F. Oggier, G. Rekaya-Ben Othman, J.-C. Belfiore and E. Viterbo
|
Perfect Space Time Block Codes
|
39 pages, 7 figures, submitted to IEEE Trans. on Inform. Theory Sep.
2004, revised version
| null | null | null |
cs.IT math.IT
| null |
In this paper, we introduce the notion of perfect space-time block codes
(STBC). These codes have full rate, full diversity, non-vanishing constant
minimum determinant for increasing spectral efficiency, uniform average
transmitted energy per antenna and good shaping. We present algebraic
constructions of perfect STBCs for 2, 3, 4 and 6 antennas.
|
[
{
"version": "v1",
"created": "Mon, 24 Apr 2006 13:07:32 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Oggier",
"F.",
""
],
[
"Othman",
"G. Rekaya-Ben",
""
],
[
"Belfiore",
"J. -C.",
""
],
[
"Viterbo",
"E.",
""
]
] |
new_dataset
| 0.997171 |
cs/0609006
|
Eric Chen
|
Eric Zhi Chen
|
New Quasi-Cyclic Codes from Simplex Codes
|
3 pages
| null | null | null |
cs.IT math.IT
| null |
As a generalization of cyclic codes, quasi-cyclic (QC) codes contain many
good linear codes. But quasi-cyclic codes studied so far are mainly limited to
one generator (1-generator) QC codes. In this correspondence, 2-generator and
3-generator QC codes are studied, and many good, new QC codes are constructed
from simplex codes. Some new binary QC codes or related codes, that improve the
bounds on maximum minimum distance for binary linear codes are constructed.
They are 5-generator QC [93, 17, 34] and [254, 23, 102] codes, and related [96,
17, 36], [256, 23, 104] codes.
|
[
{
"version": "v1",
"created": "Sat, 2 Sep 2006 11:08:15 GMT"
},
{
"version": "v2",
"created": "Mon, 20 Nov 2006 15:22:14 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Chen",
"Eric Zhi",
""
]
] |
new_dataset
| 0.999743 |
cs/0610100
|
Henry Jerez
|
Henry N Jerez, Joud Khoury, Chaouki Abdallah
|
A Mobile Transient Internet Architecture
| null | null | null | null |
cs.NI cs.IT math.IT
| null |
This paper describes a new architecture for transient mobile networks
destined to merge existing and future network architectures, communication
implementations and protocol operations by introducing a new paradigm to data
delivery and identification. The main goal of our research is to enable
seamless end-to-end communication between mobile and stationary devices across
multiple networks and through multiple communication environments. The
architecture establishes a set of infrastructure components and protocols that
set the ground for a Persistent Identification Network (PIN). The basis for the
operation of PIN is an identification space consisting of unique location
independent identifiers similar to the ones implemented in the Handle system.
Persistent Identifiers are used to identify and locate Digital Entities which
can include devices, services, users and even traffic. The architecture
establishes a primary connection independent logical structure that can operate
over conventional networks or more advanced peer-to-peer aggregation networks.
Communication is based on routing pools and novel protocols for routing data
across several abstraction levels of the network, regardless of the end-points'
current association and state...
|
[
{
"version": "v1",
"created": "Tue, 17 Oct 2006 04:47:06 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Jerez",
"Henry N",
""
],
[
"Khoury",
"Joud",
""
],
[
"Abdallah",
"Chaouki",
""
]
] |
new_dataset
| 0.985217 |
cs/0610160
|
G.Susinder Rajan
|
G. Susinder Rajan, B. Sundar Rajan
|
A Non-Orthogonal Distributed Space-Time Coded Protocol Part II-Code
Construction and DM-G Tradeoff
|
Proceedings 2006 IEEE Information Theory Workshop, Chengdu, China (5
pages, No figures)
|
Proceedings of IEEE ITW'06, Chengdu, China, October 22-26, 2006,
pp. 488-492
| null | null |
cs.IT math.IT
| null |
This is the second part of a two-part series of papers. In this paper, for
the generalized non-orthogonal amplify and forward (GNAF) protocol presented in
Part-I, a construction of a new family of distributed space-time codes based on
Co-ordinate Interleaved Orthogonal Designs (CIOD) which result in reduced
Maximum Likelihood (ML) decoding complexity at the destination is proposed.
Further, it is established that the recently proposed Toeplitz space-time codes
as well as space-time block codes (STBCs) from cyclic division algebras can be
used in GNAF protocol. Finally, a lower bound on the optimal
Diversity-Multiplexing Gain (DM-G) tradeoff for the GNAF protocol is
established and it is shown that this bound approaches the transmit diversity
bound asymptotically as the number of relays and the number of channels uses
increases.
|
[
{
"version": "v1",
"created": "Sun, 29 Oct 2006 12:49:49 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Rajan",
"G. Susinder",
""
],
[
"Rajan",
"B. Sundar",
""
]
] |
new_dataset
| 0.99321 |
cs/0610161
|
B.Sundar Rajan
|
G. Susinder Rajan, B. Sundar Rajan
|
A Non-Orthogonal Distributed Space-Time Coded Protocol Part I: Signal
Model and Design Criteria
|
5 pages, 2 figures, Proceedings of 2006 IEEE Information Theory
Workshop (ITW'06), (A typo in equation (1) in the proceedings has been
corrected.)
|
Proceedings of 2006 IEEE Information Theory Workshop (ITW'06),
Oct. 22-26, 2006, Chengdu, China, pp.385-389
| null | null |
cs.IT math.IT
| null |
In this two-part series of papers, a generalized non-orthogonal amplify and
forward (GNAF) protocol which generalizes several known cooperative diversity
protocols is proposed. Transmission in the GNAF protocol comprises of two
phases - the broadcast phase and the cooperation phase. In the broadcast phase,
the source broadcasts its information to the relays as well as the destination.
In the cooperation phase, the source and the relays together transmit a
space-time code in a distributed fashion. The GNAF protocol relaxes the
constraints imposed by the protocol of Jing and Hassibi on the code structure.
In Part-I of this paper, a code design criteria is obtained and it is shown
that the GNAF protocol is delay efficient and coding gain efficient as well.
Moreover GNAF protocol enables the use of sphere decoders at the destination
with a non-exponential Maximum likelihood (ML) decoding complexity. In Part-II,
several low decoding complexity code constructions are studied and a lower
bound on the Diversity-Multiplexing Gain tradeoff of the GNAF protocol is
obtained.
|
[
{
"version": "v1",
"created": "Sun, 29 Oct 2006 13:43:39 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Rajan",
"G. Susinder",
""
],
[
"Rajan",
"B. Sundar",
""
]
] |
new_dataset
| 0.983088 |
cs/0612032
|
Marat Burnashev V.
|
Marat V. Burnashev
|
Code Spectrum and Reliability Function: Binary Symmetric Channel
|
23 pages, to be published in Problems of Information Transmission
|
Problems of Information Transmission, vol. 42, no. 4, pp. 3-22,
2006
| null | null |
cs.IT math.IT
| null |
A new approach for upper bounding the channel reliability function using the
code spectrum is described. It allows to treat in a unified way both a low and
a high rate cases. In particular, the earlier known upper bounds are improved,
and a new derivation of the sphere-packing bound is presented.
|
[
{
"version": "v1",
"created": "Wed, 6 Dec 2006 02:14:08 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Burnashev",
"Marat V.",
""
]
] |
new_dataset
| 0.999125 |
cs/0701112
|
Axel Kohnert
|
Axel Kohnert
|
(l,s)-Extension of Linear Codes
|
8 pages
| null | null | null |
cs.IT math.CO math.IT
| null |
We construct new linear codes with high minimum distance d. In at least 12
cases these codes improve the minimum distance of the previously known best
linear codes for fixed parameters n,k. Among these new codes there is an
optimal ternary [88,8,54] code.
We develop an algorithm, which starts with already good codes C, i.e. codes
with high minimum distance d for given length n and dimension k over the field
GF(q). The algorithm is based on the newly defined (l,s)-extension. This is a
generalization of the well-known method of adding a parity bit in the case of a
binary linear code of odd minimum weight. (l,s)-extension tries to extend the
generator matrix of C by adding l columns with the property that at least s of
the l letters added to each of the codewords of minimum weight in C are
different from 0. If one finds such columns the minimum distance of the
extended code is d+s provided that the second smallest weight in C was at least
d+s. The question whether such columns exist can be settled using a Diophantine
system of equations.
|
[
{
"version": "v1",
"created": "Wed, 17 Jan 2007 15:50:15 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Kohnert",
"Axel",
""
]
] |
new_dataset
| 0.996026 |
cs/9901001
|
Lex Weaver
|
Jonathan Baxter, Andrew Tridgell, and Lex Weaver
|
TDLeaf(lambda): Combining Temporal Difference Learning with Game-Tree
Search
|
5 pages. Also in Proceedings of the Ninth Australian Conference on
Neural Networks (ACNN'98), Brisbane QLD, February 1998, pages 168-172
|
Australian Journal of Intelligent Information Processing Systems,
ISSN 1321-2133, Vol. 5 No. 1, Autumn 1998, pages 39-43
| null | null |
cs.LG cs.AI
| null |
In this paper we present TDLeaf(lambda), a variation on the TD(lambda)
algorithm that enables it to be used in conjunction with minimax search. We
present some experiments in both chess and backgammon which demonstrate its
utility and provide comparisons with TD(lambda) and another less radical
variant, TD-directed(lambda). In particular, our chess program, ``KnightCap,''
used TDLeaf(lambda) to learn its evaluation function while playing on the Free
Internet Chess Server (FICS, fics.onenet.net). It improved from a 1650 rating
to a 2100 rating in just 308 games. We discuss some of the reasons for this
success and the relationship between our results and Tesauro's results in
backgammon.
|
[
{
"version": "v1",
"created": "Tue, 5 Jan 1999 00:56:54 GMT"
}
] | 2007-07-16T00:00:00 |
[
[
"Baxter",
"Jonathan",
""
],
[
"Tridgell",
"Andrew",
""
],
[
"Weaver",
"Lex",
""
]
] |
new_dataset
| 0.97991 |
0704.0831
|
Brooke Shrader
|
Brooke Shrader and Anthony Ephremides
|
On packet lengths and overhead for random linear coding over the erasure
channel
|
5 pages, 5 figures, submitted to the 2007 International Wireless
Communications and Mobile Computing Conference
| null | null | null |
cs.IT math.IT
| null |
We assess the practicality of random network coding by illuminating the issue
of overhead and considering it in conjunction with increasingly long packets
sent over the erasure channel. We show that the transmission of increasingly
long packets, consisting of either of an increasing number of symbols per
packet or an increasing symbol alphabet size, results in a data rate
approaching zero over the erasure channel. This result is due to an erasure
probability that increases with packet length. Numerical results for a
particular modulation scheme demonstrate a data rate of approximately zero for
a large, but finite-length packet. Our results suggest a reduction in the
performance gains offered by random network coding.
|
[
{
"version": "v1",
"created": "Fri, 6 Apr 2007 02:25:40 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Shrader",
"Brooke",
""
],
[
"Ephremides",
"Anthony",
""
]
] |
new_dataset
| 0.974226 |
0704.1317
|
Naftali Sommer
|
Naftali Sommer, Meir Feder and Ofir Shalvi
|
Low Density Lattice Codes
|
24 pages, 4 figures. Submitted for publication in IEEE transactions
on Information Theory
| null | null | null |
cs.IT math.IT
| null |
Low density lattice codes (LDLC) are novel lattice codes that can be decoded
efficiently and approach the capacity of the additive white Gaussian noise
(AWGN) channel. In LDLC a codeword x is generated directly at the n-dimensional
Euclidean space as a linear transformation of a corresponding integer message
vector b, i.e., x = Gb, where H, the inverse of G, is restricted to be sparse.
The fact that H is sparse is utilized to develop a linear-time iterative
decoding scheme which attains, as demonstrated by simulations, good error
performance within ~0.5dB from capacity at block length of n = 100,000 symbols.
The paper also discusses convergence results and implementation considerations.
|
[
{
"version": "v1",
"created": "Wed, 11 Apr 2007 16:07:34 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Sommer",
"Naftali",
""
],
[
"Feder",
"Meir",
""
],
[
"Shalvi",
"Ofir",
""
]
] |
new_dataset
| 0.964725 |
0704.2857
|
Andrea Montanari
|
Andrea Montanari and Rudiger Urbanke
|
Modern Coding Theory: The Statistical Mechanics and Computer Science
Point of View
|
Lectures at Les Houches Summer School on `Complex Systems', July
2006, 44 pages, 25 ps figures
| null | null | null |
cs.IT cond-mat.stat-mech math.IT
| null |
These are the notes for a set of lectures delivered by the two authors at the
Les Houches Summer School on `Complex Systems' in July 2006. They provide an
introduction to the basic concepts in modern (probabilistic) coding theory,
highlighting connections with statistical mechanics. We also stress common
concepts with other disciplines dealing with similar problems that can be
generically referred to as `large graphical models'.
While most of the lectures are devoted to the classical channel coding
problem over simple memoryless channels, we present a discussion of more
complex channel models. We conclude with an overview of the main open
challenges in the field.
|
[
{
"version": "v1",
"created": "Sun, 22 Apr 2007 01:57:03 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Montanari",
"Andrea",
""
],
[
"Urbanke",
"Rudiger",
""
]
] |
new_dataset
| 0.964397 |
0704.3120
|
Oliver Henkel
|
Oliver Henkel
|
Space Time Codes from Permutation Codes
| null |
Proc. IEEE GlobeCom, San Francisco, California, Nov. 2006
| null | null |
cs.IT math.IT
| null |
A new class of space time codes with high performance is presented. The code
design utilizes tailor-made permutation codes, which are known to have large
minimal distances as spherical codes. A geometric connection between spherical
and space time codes has been used to translate them into the final space time
codes. Simulations demonstrate that the performance increases with the block
lengths, a result that has been conjectured already in previous work. Further,
the connection to permutation codes allows for moderate complex en-/decoding
algorithms.
|
[
{
"version": "v1",
"created": "Tue, 24 Apr 2007 05:45:30 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Henkel",
"Oliver",
""
]
] |
new_dataset
| 0.99962 |
0705.0081
|
Yeow Meng Chee
|
Yeow Meng Chee, San Ling
|
Constructions of q-Ary Constant-Weight Codes
|
12 pages
|
IEEE Transactions on Information Theory, Vol. 53, No. 1, January
2007, pp. 135-146
|
10.1109/TIT.2006.887499
| null |
cs.IT math.IT
| null |
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.
|
[
{
"version": "v1",
"created": "Tue, 1 May 2007 07:16:43 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Chee",
"Yeow Meng",
""
],
[
"Ling",
"San",
""
]
] |
new_dataset
| 0.961867 |
0705.1183
|
Ruoheng Liu
|
Ruoheng Liu and H. Vincent Poor
|
Multiple Antenna Secure Broadcast over Wireless Networks
|
14 pages, 3 figures, to appear in the Proceedings of the First
International Workshop on Information Theory for Sensor Networks, Santa Fe,
NM, June 18 - 20, 2007
| null | null | null |
cs.IT math.IT
| null |
In wireless data networks, communication is particularly susceptible to
eavesdropping due to its broadcast nature. Security and privacy systems have
become critical for wireless providers and enterprise networks. This paper
considers the problem of secret communication over the Gaussian broadcast
channel, where a multi-antenna transmitter sends independent confidential
messages to two users with perfect secrecy. That is, each user would like to
obtain its own message reliably and confidentially. First, a computable
Sato-type outer bound on the secrecy capacity region is provided for a
multi-antenna broadcast channel with confidential messages. Next, a dirty-paper
secure coding scheme and its simplified version are described. For each case,
the corresponding achievable rate region is derived under the perfect secrecy
requirement. Finally, two numerical examples demonstrate that the Sato-type
outer bound is consistent with the boundary of the simplified dirty-paper
coding secrecy rate region.
|
[
{
"version": "v1",
"created": "Tue, 8 May 2007 21:50:24 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Liu",
"Ruoheng",
""
],
[
"Poor",
"H. Vincent",
""
]
] |
new_dataset
| 0.99654 |
0705.1384
|
Navin Kashyap
|
Navin Kashyap
|
Matroid Pathwidth and Code Trellis Complexity
|
Submitted to SIAM Journal on Discrete Mathematics; 18 pages, 6
figures
| null | null | null |
cs.DM cs.IT math.IT
| null |
We relate the notion of matroid pathwidth to the minimum trellis
state-complexity (which we term trellis-width) of a linear code, and to the
pathwidth of a graph. By reducing from the problem of computing the pathwidth
of a graph, we show that the problem of determining the pathwidth of a
representable matroid is NP-hard. Consequently, the problem of computing the
trellis-width of a linear code is also NP-hard. For a finite field $\F$, we
also consider the class of $\F$-representable matroids of pathwidth at most
$w$, and correspondingly, the family of linear codes over $\F$ with
trellis-width at most $w$. These are easily seen to be minor-closed. Since
these matroids (and codes) have branchwidth at most $w$, a result of Geelen and
Whittle shows that such matroids (and the corresponding codes) are
characterized by finitely many excluded minors. We provide the complete list of
excluded minors for $w=1$, and give a partial list for $w=2$.
|
[
{
"version": "v1",
"created": "Thu, 10 May 2007 03:00:54 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Kashyap",
"Navin",
""
]
] |
new_dataset
| 0.999272 |
0706.0682
|
Marat Burnashev V.
|
Marat V. Burnashev
|
Code spectrum and reliability function: Gaussian channel
|
24 pages, 1 figure
|
Problems of Information Transmission, vol. 43, no. 2, pp. 3-24,
2007
| null | null |
cs.IT math.IT
| null |
A new approach for upper bounding the channel reliability function using the
code spectrum is described. It allows to treat both low and high rate cases in
a unified way. In particular, the earlier known upper bounds are improved, and
a new derivation of the sphere-packing bound is presented.
|
[
{
"version": "v1",
"created": "Tue, 5 Jun 2007 19:08:59 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Burnashev",
"Marat V.",
""
]
] |
new_dataset
| 0.993024 |
0706.0869
|
Edward Aboufadel
|
Edward Aboufadel, Timothy Armstrong, Elizabeth Smietana
|
Position Coding
|
14 pages, 7 figures
| null | null | null |
cs.IT math.CO math.IT
| null |
A position coding pattern is an array of symbols in which subarrays of a
certain fixed size appear at most once. So, each subarray uniquely identifies a
location in the larger array, which means there is a bijection of some sort
from this set of subarrays to a set of coordinates. The key to Fly Pentop
Computer paper and other examples of position codes is a method to read the
subarray and then convert it to coordinates. Position coding makes use of ideas
from discrete mathematics and number theory. In this paper, we will describe
the underlying mathematics of two position codes, one being the Anoto code that
is the basis of "Fly paper". Then, we will present two new codes, one which
uses binary wavelets as part of the bijection.
|
[
{
"version": "v1",
"created": "Wed, 6 Jun 2007 17:09:21 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Aboufadel",
"Edward",
""
],
[
"Armstrong",
"Timothy",
""
],
[
"Smietana",
"Elizabeth",
""
]
] |
new_dataset
| 0.98673 |
0706.3502
|
P Vijay Kumar
|
Petros Elia and P. Vijay Kumar
|
Approximately-Universal Space-Time Codes for the Parallel, Multi-Block
and Cooperative-Dynamic-Decode-and-Forward Channels
| null | null | null | null |
cs.IT cs.DM cs.NI math.IT
| null |
Explicit codes are constructed that achieve the diversity-multiplexing gain
tradeoff of the cooperative-relay channel under the dynamic decode-and-forward
protocol for any network size and for all numbers of transmit and receive
antennas at the relays.
A particularly simple code construction that makes use of the Alamouti code
as a basic building block is provided for the single relay case.
Along the way, we prove that space-time codes previously constructed in the
literature for the block-fading and parallel channels are approximately
universal, i.e., they achieve the DMT for any fading distribution. It is shown
how approximate universality of these codes leads to the first DMT-optimum code
construction for the general, MIMO-OFDM channel.
|
[
{
"version": "v1",
"created": "Sun, 24 Jun 2007 07:47:57 GMT"
},
{
"version": "v2",
"created": "Fri, 13 Jul 2007 12:43:51 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Elia",
"Petros",
""
],
[
"Kumar",
"P. Vijay",
""
]
] |
new_dataset
| 0.999758 |
0707.0459
|
Petar Popovski
|
Petar Popovski and Hiroyuki Yomo
|
Physical Network Coding in Two-Way Wireless Relay Channels
| null |
Proc. of IEEE International Conference on Communications (ICC),
Glasgow, Scotland, 2007
| null | null |
cs.IT cs.NI math.IT
| null |
It has recently been recognized that the wireless networks represent a
fertile ground for devising communication modes based on network coding. A
particularly suitable application of the network coding arises for the two--way
relay channels, where two nodes communicate with each other assisted by using a
third, relay node. Such a scenario enables application of \emph{physical
network coding}, where the network coding is either done (a) jointly with the
channel coding or (b) through physical combining of the communication flows
over the multiple access channel. In this paper we first group the existing
schemes for physical network coding into two generic schemes, termed 3--step
and 2--step scheme, respectively. We investigate the conditions for
maximization of the two--way rate for each individual scheme: (1) the
Decode--and--Forward (DF) 3--step schemes (2) three different schemes with two
steps: Amplify--and--Forward (AF), JDF and Denoise--and--Forward (DNF). While
the DNF scheme has a potential to offer the best two--way rate, the most
interesting result of the paper is that, for some SNR configurations of the
source--relay links, JDF yields identical maximal two--way rate as the upper
bound on the rate for DNF.
|
[
{
"version": "v1",
"created": "Tue, 3 Jul 2007 16:40:41 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Popovski",
"Petar",
""
],
[
"Yomo",
"Hiroyuki",
""
]
] |
new_dataset
| 0.999362 |
0707.0860
|
Mohammad Asad Rehman Chaudhry
|
Salim Y. El Rouayheb, Mohammad Asad R. Chaudhry, and Alex Sprintson
|
On the Minimum Number of Transmissions in Single-Hop Wireless Coding
Networks
|
6 pages
| null | null | null |
cs.IT cs.NI math.IT
| null |
The advent of network coding presents promising opportunities in many areas
of communication and networking. It has been recently shown that network coding
technique can significantly increase the overall throughput of wireless
networks by taking advantage of their broadcast nature. In wireless networks,
each transmitted packet is broadcasted within a certain area and can be
overheard by the neighboring nodes. When a node needs to transmit packets, it
employs the opportunistic coding approach that uses the knowledge of what the
node's neighbors have heard in order to reduce the number of transmissions.
With this approach, each transmitted packet is a linear combination of the
original packets over a certain finite field.
In this paper, we focus on the fundamental problem of finding the optimal
encoding for the broadcasted packets that minimizes the overall number of
transmissions. We show that this problem is NP-complete over GF(2) and
establish several fundamental properties of the optimal solution. We also
propose a simple heuristic solution for the problem based on graph coloring and
present some empirical results for random settings.
|
[
{
"version": "v1",
"created": "Thu, 5 Jul 2007 19:58:23 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Rouayheb",
"Salim Y. El",
""
],
[
"Chaudhry",
"Mohammad Asad R.",
""
],
[
"Sprintson",
"Alex",
""
]
] |
new_dataset
| 0.9933 |
cs/0411003
|
Andrew Thangaraj
|
Andrew Thangaraj, Souvik Dihidar, A. R. Calderbank, Steven McLaughlin,
Jean-Marc Merolla
|
Applications of LDPC Codes to the Wiretap Channel
|
30 pages, revised version
| null | null | null |
cs.IT cs.CR math.IT
| null |
With the advent of quantum key distribution (QKD) systems, perfect (i.e.
information-theoretic) security can now be achieved for distribution of a
cryptographic key. QKD systems and similar protocols use classical
error-correcting codes for both error correction (for the honest parties to
correct errors) and privacy amplification (to make an eavesdropper fully
ignorant). From a coding perspective, a good model that corresponds to such a
setting is the wire tap channel introduced by Wyner in 1975. In this paper, we
study fundamental limits and coding methods for wire tap channels. We provide
an alternative view of the proof for secrecy capacity of wire tap channels and
show how capacity achieving codes can be used to achieve the secrecy capacity
for any wiretap channel. We also consider binary erasure channel and binary
symmetric channel special cases for the wiretap channel and propose specific
practical codes. In some cases our designs achieve the secrecy capacity and in
others the codes provide security at rates below secrecy capacity. For the
special case of a noiseless main channel and binary erasure channel, we
consider encoder and decoder design for codes achieving secrecy on the wiretap
channel; we show that it is possible to construct linear-time decodable secrecy
codes based on LDPC codes that achieve secrecy.
|
[
{
"version": "v1",
"created": "Tue, 2 Nov 2004 10:21:59 GMT"
},
{
"version": "v2",
"created": "Mon, 24 Oct 2005 12:18:05 GMT"
},
{
"version": "v3",
"created": "Mon, 29 Jan 2007 08:24:04 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Thangaraj",
"Andrew",
""
],
[
"Dihidar",
"Souvik",
""
],
[
"Calderbank",
"A. R.",
""
],
[
"McLaughlin",
"Steven",
""
],
[
"Merolla",
"Jean-Marc",
""
]
] |
new_dataset
| 0.99856 |
cs/0412111
|
Alexander Barg
|
Alexander Barg
|
On the asymptotic accuracy of the union bound
|
10 pages, 3 figures. Presented at the 42nd Annual Allerton Conference
on Communication, Control and Computing (Sept. 29 - Oct. 1, 2004). The paper
will appear in the conference proceedings. Version 2 differs slightly from
the published version and is the latest version of this paper
| null | null | null |
cs.IT math.IT
| null |
A new lower bound on the error probability of maximum likelihood decoding of
a binary code on a binary symmetric channel was proved in Barg and McGregor
(2004, cs.IT/0407011). It was observed in that paper that this bound leads to a
new region of code rates in which the random coding exponent is asymptotically
tight, giving a new region in which the reliability of the BSC is known
exactly. The present paper explains the relation of these results to the union
bound on the error probability.
|
[
{
"version": "v1",
"created": "Fri, 24 Dec 2004 19:43:26 GMT"
},
{
"version": "v2",
"created": "Mon, 25 Apr 2005 18:38:53 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Barg",
"Alexander",
""
]
] |
new_dataset
| 0.975513 |
cs/0501016
|
Heide Gluesing-Luerssen
|
Heide Gluesing-Luerssen
|
On the weight distribution of convolutional codes
| null | null | null | null |
cs.IT math.IT math.OC
| null |
Detailed information about the weight distribution of a convolutional code is
given by the adjacency matrix of the state diagram associated with a controller
canonical form of the code. We will show that this matrix is an invariant of
the code. Moreover, it will be proven that codes with the same adjacency matrix
have the same dimension and the same Forney indices and finally that for
one-dimensional binary convolutional codes the adjacency matrix determines the
code uniquely up to monomial equivalence.
|
[
{
"version": "v1",
"created": "Mon, 10 Jan 2005 14:08:27 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Gluesing-Luerssen",
"Heide",
""
]
] |
new_dataset
| 0.974646 |
cs/0502037
|
Cen Jung Tjhai
|
C. Tjhai, M. Tomlinson, R. Horan, M. Ambroze and M. Ahmed
|
GF(2^m) Low-Density Parity-Check Codes Derived from Cyclotomic Cosets
|
Coding
| null | null | null |
cs.IT math.IT
| null |
Based on the ideas of cyclotomic cosets, idempotents and Mattson-Solomon
polynomials, we present a new method to construct GF(2^m), where m>0 cyclic
low-density parity-check codes. The construction method produces the dual code
idempotent which is used to define the parity-check matrix of the low-density
parity-check code. An interesting feature of this construction method is the
ability to increment the code dimension by adding more idempotents and so
steadily decrease the sparseness of the parity-check matrix. We show that the
constructed codes can achieve performance very close to the
sphere-packing-bound constrained for binary transmission.
|
[
{
"version": "v1",
"created": "Mon, 7 Feb 2005 11:37:56 GMT"
},
{
"version": "v2",
"created": "Sat, 23 Jul 2005 12:22:12 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Tjhai",
"C.",
""
],
[
"Tomlinson",
"M.",
""
],
[
"Horan",
"R.",
""
],
[
"Ambroze",
"M.",
""
],
[
"Ahmed",
"M.",
""
]
] |
new_dataset
| 0.999077 |
cs/0504020
|
G David Forney Jr.
|
G. David Forney Jr
|
The Viterbi Algorithm: A Personal History
|
8 pages; presented at Viterbi Conference, University of Southern
California, Los Angeles, March 8, 2005
| null | null | null |
cs.IT math.IT
| null |
The story of the Viterbi algorithm (VA) is told from a personal perspective.
Applications both within and beyond communications are discussed. In brief
summary, the VA has proved to be an extremely important algorithm in a
surprising variety of fields.
|
[
{
"version": "v1",
"created": "Wed, 6 Apr 2005 15:59:31 GMT"
},
{
"version": "v2",
"created": "Fri, 29 Apr 2005 15:06:00 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Forney",
"G. David",
"Jr"
]
] |
new_dataset
| 0.969003 |
cs/0504028
|
Michael Peleg
|
Michael Peleg, Amichai Sanderovich and Shlomo Shamai
|
On Extrinsic Information of Good Codes Operating Over Discrete
Memoryless Channels
| null | null | null |
CCIT-525
|
cs.IT math.IT
| null |
We show that the Extrinsic Information about the coded bits of any good
(capacity achieving) code operating over a wide class of discrete memoryless
channels (DMC) is zero when channel capacity is below the code rate and
positive constant otherwise, that is, the Extrinsic Information Transfer (EXIT)
chart is a step function of channel quality, for any capacity achieving code.
It follows that, for a common class of iterative receivers where the error
correcting decoder must operate at first iteration at rate above capacity (such
as in turbo equalization, turbo channel estimation, parallel and serial
concatenated coding and the like), classical good codes which achieve capacity
over the DMC are not effective and should be replaced by different new ones.
Another meaning of the results is that a good code operating at rate above
channel capacity falls apart into its individual transmitted symbols in the
sense that all the information about a coded transmitted symbol is contained in
the corresponding received symbol and no information about it can be inferred
from the other received symbols. The binary input additive white Gaussian noise
channel is treated in part 1 of this report. Part 2 extends the results to the
symmetric binary channel and to the binary erasure channel and provides an
heuristic extension to wider class of channel models.
|
[
{
"version": "v1",
"created": "Thu, 7 Apr 2005 17:35:05 GMT"
},
{
"version": "v2",
"created": "Thu, 14 Apr 2005 06:58:36 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Peleg",
"Michael",
""
],
[
"Sanderovich",
"Amichai",
""
],
[
"Shamai",
"Shlomo",
""
]
] |
new_dataset
| 0.975992 |
cs/0504047
|
David Doty
|
David Doty, Jared Nichols
|
Pushdown dimension
|
10 page main body; 12 page appendix of proofs
| null | null | null |
cs.IT cs.CC math.IT
| null |
This paper develops the theory of pushdown dimension and explores its
relationship with finite-state dimension. Pushdown dimension is trivially
bounded above by finite-state dimension for all sequences, since a pushdown
gambler can simulate any finite-state gambler. We show that for every rational
0 < d < 1, there exists a sequence with finite-state dimension d whose pushdown
dimension is at most d/2. This establishes a quantitative analogue of the
well-known fact that pushdown automata decide strictly more languages than
finite automata.
|
[
{
"version": "v1",
"created": "Tue, 12 Apr 2005 22:13:12 GMT"
},
{
"version": "v2",
"created": "Wed, 13 Apr 2005 23:12:11 GMT"
},
{
"version": "v3",
"created": "Fri, 22 Apr 2005 05:09:08 GMT"
},
{
"version": "v4",
"created": "Fri, 27 May 2005 02:46:26 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Doty",
"David",
""
],
[
"Nichols",
"Jared",
""
]
] |
new_dataset
| 0.985875 |
cs/0506091
|
Oscar Takeshita
|
Oscar Y. Takeshita
|
A New Construction for LDPC Codes using Permutation Polynomials over
Integer Rings
|
12 pages, 4 figures, submitted to IEEE Transactions on Information
Theory
| null | null | null |
cs.IT math.IT
| null |
A new construction is proposed for low density parity check (LDPC) codes
using quadratic permutation polynomials over finite integer rings. The
associated graphs for the new codes have both algebraic and pseudo-random
nature, and the new codes are quasi-cyclic. Graph isomorphisms and
automorphisms are identified and used in an efficient search for good codes.
Graphs with girth as large as 12 were found. Upper bounds on the minimum
Hamming distance are found both analytically and algorithmically. The bounds
indicate that the minimum distance grows with block length. Near-codewords are
one of the causes for error floors in LDPC codes; the new construction provides
a good framework for studying near-codewords in LDPC codes. Nine example codes
are given, and computer simulation results show the excellent error performance
of these codes. Finally, connections are made between this new LDPC
construction and turbo codes using interleavers generated by quadratic
permutation polynomials.
|
[
{
"version": "v1",
"created": "Fri, 24 Jun 2005 15:37:04 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Takeshita",
"Oscar Y.",
""
]
] |
new_dataset
| 0.999485 |
cs/0506102
|
John B. Little
|
John Little, Ryan Schwarz
|
On $m$-dimensional toric codes
|
17 pages, 4 figures; typos corrected
| null | null | null |
cs.IT math.AC math.AG math.IT
| null |
Toric codes are a class of $m$-dimensional cyclic codes introduced recently
by J. Hansen. They may be defined as evaluation codes obtained from monomials
corresponding to integer lattice points in an integral convex polytope $P
\subseteq \R^m$. As such, they are in a sense a natural extension of
Reed-Solomon codes. Several authors have used intersection theory on toric
surfaces to derive bounds on the minimum distance of some toric codes with $m =
2$. In this paper, we will provide a more elementary approach that applies
equally well to many toric codes for all $m \ge 2$. Our methods are based on a
sort of multivariate generalization of Vandermonde determinants that has also
been used in the study of multivariate polynomial interpolation. We use these
Vandermonde determinants to determine the minimum distance of toric codes from
rectangular polytopes and simplices. We also prove a general result showing
that if there is a unimodular integer affine transformation taking one polytope
$P_1$ to a second polytope $P_2$, then the corresponding toric codes are
monomially equivalent (hence have the same parameters). We use this to begin a
classification of two-dimensional toric codes with small dimension.
|
[
{
"version": "v1",
"created": "Wed, 29 Jun 2005 21:09:37 GMT"
},
{
"version": "v2",
"created": "Mon, 25 Jul 2005 14:15:38 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Little",
"John",
""
],
[
"Schwarz",
"Ryan",
""
]
] |
new_dataset
| 0.999401 |
cs/0507031
|
Misha Stepanov
|
M. G. Stepanov, M. Chertkov
|
The error-floor of LDPC codes in the Laplacian channel
|
43rd Allerton Conference (September 28-30, 2005, Allerton, IL)
| null | null |
LA-UR-05-5131
|
cs.IT cond-mat.dis-nn math.IT
| null |
We analyze the performance of Low-Density-Parity-Check codes in the
error-floor domain where the Signal-to-Noise-Ratio, s, is large, s >> 1. We
describe how the instanton method of theoretical physics, recently adapted to
coding theory, solves the problem of characterizing the error-floor domain in
the Laplacian channel. An example of the (155,64,20) LDPC code with four
iterations (each iteration consisting of two semi-steps: from bits-to-checks
and from checks-to-bits) of the min-sum decoding is discussed. A generalized
computational tree analysis is devised to explain the rational structure of the
leading instantons. The asymptotic for the symbol Bit-Error-Rate in the
error-floor domain is comprised of individual instanton contributions, each
estimated as ~ \exp(-l_{inst;L} s), where the effective distances, l_{inst;L},
of the the leading instantons are 7.6, 8.0 and 8.0 respectively. (The Hamming
distance of the code is 20.) The analysis shows that the instantons are
distinctly different from the ones found for the same coding/decoding scheme
performing over the Gaussian channel. We validate instanton results against
direct simulations and offer an explanation for remarkable performance of the
instanton approximation not only in the extremal, s -> \infty, limit but also
at the moderate s values of practical interest.
|
[
{
"version": "v1",
"created": "Tue, 12 Jul 2005 02:02:23 GMT"
},
{
"version": "v2",
"created": "Mon, 3 Oct 2005 17:33:02 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Stepanov",
"M. G.",
""
],
[
"Chertkov",
"M.",
""
]
] |
new_dataset
| 0.999559 |
cs/0508001
|
Xiaoyang Gu
|
Xiaoyang Gu, Jack H. Lutz, Philippe Moser
|
Dimensions of Copeland-Erdos Sequences
|
19 pages
| null | null | null |
cs.CC cs.IT math.IT
| null |
The base-$k$ {\em Copeland-Erd\"os sequence} given by an infinite set $A$ of
positive integers is the infinite sequence $\CE_k(A)$ formed by concatenating
the base-$k$ representations of the elements of $A$ in numerical order. This
paper concerns the following four quantities.
The {\em finite-state dimension} $\dimfs (\CE_k(A))$, a finite-state version
of classical Hausdorff dimension introduced in 2001.
The {\em finite-state strong dimension} $\Dimfs(\CE_k(A))$, a finite-state
version of classical packing dimension introduced in 2004. This is a dual of
$\dimfs(\CE_k(A))$ satisfying $\Dimfs(\CE_k(A))$ $\geq \dimfs(\CE_k(A))$.
The {\em zeta-dimension} $\Dimzeta(A)$, a kind of discrete fractal dimension
discovered many times over the past few decades.
The {\em lower zeta-dimension} $\dimzeta(A)$, a dual of $\Dimzeta(A)$
satisfying $\dimzeta(A)\leq \Dimzeta(A)$.
We prove the following.
$\dimfs(\CE_k(A))\geq \dimzeta(A)$. This extends the 1946 proof by Copeland
and Erd\"os that the sequence $\CE_k(\mathrm{PRIMES})$ is Borel normal.
$\Dimfs(\CE_k(A))\geq \Dimzeta(A)$.
These bounds are tight in the strong sense that these four quantities can
have (simultaneously) any four values in $[0,1]$ satisfying the four
above-mentioned inequalities.
|
[
{
"version": "v1",
"created": "Sat, 30 Jul 2005 04:30:05 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Gu",
"Xiaoyang",
""
],
[
"Lutz",
"Jack H.",
""
],
[
"Moser",
"Philippe",
""
]
] |
new_dataset
| 0.98488 |
cs/0508015
|
Stanislav Bulygin V.
|
Stanislav Bulygin
|
Chosen-ciphertext attack on noncommutative Polly Cracker
| null | null | null | null |
cs.IT cs.CR math.IT
| null |
We propose a chosen-ciphertext attack on recently presented noncommutative
variant of the well-known Polly Cracker cryptosystem. We show that if one
chooses parameters for this noncommutative Polly Cracker as initially proposed,
than the system should be claimed as insecure.
|
[
{
"version": "v1",
"created": "Tue, 2 Aug 2005 09:48:43 GMT"
},
{
"version": "v2",
"created": "Tue, 8 Nov 2005 19:11:32 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Bulygin",
"Stanislav",
""
]
] |
new_dataset
| 0.995372 |
cs/0508020
|
Chris Ng
|
Chris T. K. Ng and Andrea J. Goldsmith
|
Capacity Gain from Transmitter and Receiver Cooperation
|
To appear in the proceedings of the 2005 IEEE International Symposium
on Information Theory, Adelaide, Australia, September 4-9, 2005
| null | null | null |
cs.IT math.IT
| null |
Capacity gain from transmitter and receiver cooperation are compared in a
relay network where the cooperating nodes are close together. When all nodes
have equal average transmit power along with full channel state information
(CSI), it is proved that transmitter cooperation outperforms receiver
cooperation, whereas the opposite is true when power is optimally allocated
among the nodes but only receiver phase CSI is available. In addition, when the
nodes have equal average power with receiver phase CSI only, cooperation is
shown to offer no capacity improvement over a non-cooperative scheme with the
same average network power. When the system is under optimal power allocation
with full CSI, the decode-and-forward transmitter cooperation rate is close to
its cut-set capacity upper bound, and outperforms compress-and-forward receiver
cooperation. Moreover, it is shown that full CSI is essential in transmitter
cooperation, while optimal power allocation is essential in receiver
cooperation.
|
[
{
"version": "v1",
"created": "Tue, 2 Aug 2005 18:03:14 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Ng",
"Chris T. K.",
""
],
[
"Goldsmith",
"Andrea J.",
""
]
] |
new_dataset
| 0.963679 |
cs/0508024
|
Kai-Uwe Schmidt
|
Kai-Uwe Schmidt and Adolf Finger
|
New Codes for OFDM with Low PMEPR
|
To appear in the Proceedings of IEEE International Symposium on
Information Theory, Sept. 4-9, 2005, Adelaide, Australia
| null | null | null |
cs.IT math.IT
| null |
In this paper new codes for orthogonal frequency-division multiplexing (OFDM)
with tightly controlled peak-to-mean envelope power ratio (PMEPR) are proposed.
We identify a new family of sequences occuring in complementary sets and show
that such sequences form subsets of a new generalization of the Reed--Muller
codes. Contrarily to previous constructions we present a compact description of
such codes, which makes them suitable even for larger block lengths. We also
show that some previous constructions just occur as special cases in our
construction.
|
[
{
"version": "v1",
"created": "Wed, 3 Aug 2005 07:22:41 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Schmidt",
"Kai-Uwe",
""
],
[
"Finger",
"Adolf",
""
]
] |
new_dataset
| 0.999779 |
cs/0508025
|
S\'andor Gy\H{o}ri
|
S\'andor Gy\H{o}ri
|
Signature coding for OR channel with asynchronous access
|
To appear in the proceedings of the 2005 IEEE International Symposium
on Information Theory, Adelaide, Australia, September 4-9, 2005
| null | null | null |
cs.IT math.IT
| null |
Signature coding for multiple access OR channel is considered. We prove that
in block asynchronous case the upper bound on the minimum code length
asymptotically is the same as in the case of synchronous access.
|
[
{
"version": "v1",
"created": "Wed, 3 Aug 2005 10:47:00 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Győri",
"Sándor",
""
]
] |
new_dataset
| 0.997605 |
cs/0508107
|
Beniamin Mounits Mr
|
Beniamin Mounits (1), Tuvi Etzion (1) and Simon Litsyn (2) ((1)
Technion - Israel Institute of Technology, (2) Tel Aviv University)
|
New Upper Bounds on A(n,d)
|
To appear in the proceedings of the 2005 IEEE International Symposium
on Information Theory, Adelaide, Australia, September 4-9, 2005
| null | null | null |
cs.IT cs.DM math.IT
| null |
Upper bounds on the maximum number of codewords in a binary code of a given
length and minimum Hamming distance are considered. New bounds are derived by a
combination of linear programming and counting arguments. Some of these bounds
improve on the best known analytic bounds. Several new record bounds are
obtained for codes with small lengths.
|
[
{
"version": "v1",
"created": "Wed, 24 Aug 2005 12:27:00 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Mounits",
"Beniamin",
""
],
[
"Etzion",
"Tuvi",
""
],
[
"Litsyn",
"Simon",
""
]
] |
new_dataset
| 0.970114 |
cs/0509044
|
Igal Sason
|
Henry D. Pfister and Igal Sason
|
Accumulate-Repeat-Accumulate Codes: Systematic Codes Achieving the
Binary Erasure Channel Capacity with Bounded Complexity
|
15 pages, 3 figures (please ignore the 16th page in the PDF file,
which appears as a result of a temporary problem in the compilation of the
PDF; however, the PS file is indeed 15 pages). The paper will be presented in
the Forty-Third Annual Allerton Conference on Communication, Control and
Computing, Monticello, IL, USA, Sept. 28-30, 2005
| null | null | null |
cs.IT math.IT
| null |
The paper introduces ensembles of accumulate-repeat-accumulate (ARA) codes
which asymptotically achieve capacity on the binary erasure channel (BEC) with
{\em bounded complexity} per information bit. It also introduces symmetry
properties which play a central role in the construction of capacity-achieving
ensembles for the BEC. The results here improve on the tradeoff between
performance and complexity provided by the first capacity-achieving ensembles
of irregular repeat-accumulate (IRA) codes with bounded complexity per
information bit; these IRA ensembles were previously constructed by Pfister,
Sason and Urbanke. The superiority of ARA codes with moderate to large block
length is exemplified by computer simulations which compare their performance
with those of previously reported capacity-achieving ensembles of LDPC and IRA
codes. The ARA codes also have the advantage of being systematic.
|
[
{
"version": "v1",
"created": "Thu, 15 Sep 2005 16:15:27 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Pfister",
"Henry D.",
""
],
[
"Sason",
"Igal",
""
]
] |
new_dataset
| 0.995917 |
cs/0510003
|
Giuseppe Abreu
|
Giuseppe Thadeu Freitas de Abreu
|
Generalized ABBA Space-Time Block Codes
|
47 pages, 6 figures, Matlab codes included
| null | null | null |
cs.IT math.IT
| null |
Linear space-time block codes (STBCs) of unitary rate and full diversity,
systematically constructed over arbitrary constellations for any number of
transmit antennas are introduced. The codes are obtained by generalizing the
existing ABBA STBCs, a.k.a quasi-orthogonal STBCs (QO-STBCs). Furthermore, a
fully orthogonal (symbol-by-symbol) decoder for the new generalized ABBA
(GABBA) codes is provided. This remarkably low-complexity decoder relies on
partition orthogonality properties of the code structure to decompose the
received signal vector into lower-dimension tuples, each dependent only on
certain subsets of the transmitted symbols. Orthogonal decodability results
from the nested application of this technique, with no matrix inversion or
iterative signal processing required. The exact bit-error-rate probability of
GABBA codes over generalized fading channels with maximum likelihood (ML)
decoding is evaluated analytically and compared against simulation results
obtained with the proposed orthogonal decoder. The comparison reveals that the
proposed GABBA solution, despite its very low complexity, achieves nearly the
same performance of the bound corresponding to the ML-decoded system,
especially in systems with large numbers of antennas.
|
[
{
"version": "v1",
"created": "Sun, 2 Oct 2005 14:10:11 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"de Abreu",
"Giuseppe Thadeu Freitas",
""
]
] |
new_dataset
| 0.99531 |
cs/0510049
|
Roxana Smarandache
|
Roxana Smarandache and Marcel Wauer
|
Bounds on the Pseudo-Weight of Minimal Pseudo-Codewords of Projective
Geometry Codes
|
12 pages 1 figure, submitted
| null | null | null |
cs.IT cs.DM math.IT
| null |
In this paper we focus our attention on a family of finite geometry codes,
called type-I projective geometry low-density parity-check (PG-LDPC) codes,
that are constructed based on the projective planes PG{2,q). In particular, we
study their minimal codewords and pseudo-codewords, as it is known that these
vectors characterize completely the code performance under maximum-likelihood
decoding and linear programming decoding, respectively. The main results of
this paper consist of upper and lower bounds on the pseudo-weight of the
minimal pseudo-codewords of type-I PG-LDPC codes.
|
[
{
"version": "v1",
"created": "Mon, 17 Oct 2005 15:46:52 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Smarandache",
"Roxana",
""
],
[
"Wauer",
"Marcel",
""
]
] |
new_dataset
| 0.980047 |
cs/0511001
|
Syed Jafar
|
Syed A. Jafar
|
Capacity with Causal and Non-Causal Side Information - A Unified View
|
This work was presented in part at the IEEE Communication Theory
Workshop, June 12-15, 2005 and at the Forty-third Annual Allerton Conference
on Communication, Control, and Computing, Sept. 28-30, 2005
| null | null | null |
cs.IT math.IT
| null |
We identify the common underlying form of the capacity expression that is
applicable to both cases where causal or non-causal side information is made
available to the transmitter. Using this common form we find that for the
single user channel, the multiple access channel, the degraded broadcast
channel, and the degraded relay channel, the sum capacity with causal and
non-causal side information are identical when all the transmitter side
information is also made available to all the receivers. A genie-aided
outerbound is developed that states that when a genie provides $n$ bits of side
information to a receiver the resulting capacity improvement can not be more
than $n$ bits. Combining these two results we are able to bound the relative
capacity advantage of non-causal side information over causal side information
for both single user as well as various multiple user communication scenarios.
Applications of these capacity bounds are demonstrated through examples of
random access channels. Interestingly, the capacity results indicate that the
excessive MAC layer overheads common in present wireless systems may be avoided
through coding across multiple access blocks. It is also shown that even one
bit of side information at the transmitter can result in unbounded capacity
improvement. As a side, we obtain the sum capacity for a multiple access
channel when the side information available to the transmitter is causal and
possibly correlated to the side information available to the receiver.
|
[
{
"version": "v1",
"created": "Mon, 31 Oct 2005 22:30:54 GMT"
},
{
"version": "v2",
"created": "Thu, 22 Jun 2006 03:13:10 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Jafar",
"Syed A.",
""
]
] |
new_dataset
| 0.996632 |
cs/0511029
|
Rasika Perera Mr
|
Rasika R Perera, Tony S Pollock, Thushara D Abhayapala
|
Non-coherent Rayleigh fading MIMO channels: Capacity Supremum
|
08 pages, 5 figures, IEEE Transactions on Information Theory
| null | null | null |
cs.IT math.IT
| null |
This paper investigates the limits of information transfer over a fast
Rayleigh fading MIMO channel, where neither the transmitter nor the receiver
has the knowledge of the channel state information (CSI) except the fading
statistics. We develop a scalar channel model due to absence of the phase
information in non-coherent Rayleigh fading and derive a capacity supremum with
the number of receive antennas at any signal to noise ratio (SNR) using
Lagrange optimisation. Also, we conceptualise the discrete nature of the
optimal input distribution by posing the optimisation on the channel mutual
information for $N$ discrete inputs. Furthermore, we derive an expression for
the asymptotic capacity when the input power is large, and compare with the
existing capacity results when the receiver is equipped with a large number of
antennas.
|
[
{
"version": "v1",
"created": "Mon, 7 Nov 2005 03:42:12 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Perera",
"Rasika R",
""
],
[
"Pollock",
"Tony S",
""
],
[
"Abhayapala",
"Thushara D",
""
]
] |
new_dataset
| 0.992085 |
cs/0511081
|
Shashibhushan Borade
|
Shashi Borade and Lizhong Zheng
|
Writing on Fading Paper and Causal Transmitter CSI
| null | null | null | null |
cs.IT math.IT
| null |
A wideband fading channel is considered with causal channel state information
(CSI) at the transmitter and no receiver CSI. A simple orthogonal code with
energy detection rule at the receiver (similar to [6]) is shown to achieve the
capacity of this channel in the limit of large bandwidth. This code transmits
energy only when the channel gain is large enough. In this limit, this capacity
without any receiver CSI is the same as the capacity with full receiver CSI--a
phenomenon also true for dirty paper coding. For Rayleigh fading, this capacity
(per unit time) is proportional to the logarithm of the bandwidth. Our coding
scheme is motivated from the Gel'fand-Pinsker [2,3] coding and dirty paper
coding [4]. Nonetheless, for our case, only causal CSI is required at the
transmitter in contrast with dirty-paper coding and Gel'fand-Pinsker coding,
where non-causal CSI is required.
Then we consider a general discrete channel with i.i.d. states. Each input
has an associated cost and a zero cost input "0" exists. The channel state is
assumed be to be known at the transmitter in a causal manner. Capacity per unit
cost is found for this channel and a simple orthogonal code is shown to achieve
this capacity. Later, a novel orthogonal coding scheme is proposed for the case
of causal transmitter CSI and a condition for equivalence of capacity per unit
cost for causal and non-causal transmitter CSI is derived. Finally, some
connections are made to the case of non-causal transmitter CSI in [8].
|
[
{
"version": "v1",
"created": "Tue, 22 Nov 2005 22:11:46 GMT"
},
{
"version": "v2",
"created": "Tue, 29 Nov 2005 01:41:01 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Borade",
"Shashi",
""
],
[
"Zheng",
"Lizhong",
""
]
] |
new_dataset
| 0.99789 |
cs/0512023
|
Petros Elia
|
Petros Elia, B. A. Sethuraman and P. Vijay Kumar
|
Perfect Space-Time Codes with Minimum and Non-Minimum Delay for Any
Number of Antennas
| null | null | null | null |
cs.IT math.IT
| null |
Perfect space-time codes were first introduced by Oggier et. al. to be the
space-time codes that have full rate, full diversity-gain, non-vanishing
determinant for increasing spectral efficiency, uniform average transmitted
energy per antenna and good shaping of the constellation. These defining
conditions jointly correspond to optimality with respect to the Zheng-Tse D-MG
tradeoff, independent of channel statistics, as well as to near optimality in
maximizing mutual information. All the above traits endow the code with error
performance that is currently unmatched. Yet perfect space-time codes have been
constructed only for 2,3,4 and 6 transmit antennas. We construct minimum and
non-minimum delay perfect codes for all channel dimensions.
|
[
{
"version": "v1",
"created": "Tue, 6 Dec 2005 02:03:25 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Elia",
"Petros",
""
],
[
"Sethuraman",
"B. A.",
""
],
[
"Kumar",
"P. Vijay",
""
]
] |
new_dataset
| 0.983748 |
cs/0512027
|
Jing Chen
|
Jing Chen
|
The Physical Foundation of Human Mind and a New Theory of Investment
| null | null | null | null |
cs.IT math.IT
| null |
This paper consists of two parts. In the first part, we develop a new
information theory, in which it is not a coincidence that information and
physical entropy share the same mathematical formula. It is an adaptation of
mind to help search for resources. We then show that psychological patterns
either reflect the constraints of physical laws or are evolutionary adaptations
to efficiently process information and to increase the chance of survival in
the environment of our evolutionary past. In the second part, we demonstrate
that the new information theory provides the foundation to understand market
behavior. One fundamental result from the information theory is that
information is costly. In general, information with higher value is more
costly. Another fundamental result from the information theory is that the
amount of information one can receive is the amount of information generated
minus equivocation. The level of equivocation, which is the measure of
information asymmetry, is determined by the correlation between the source of
information and the receiver of information. In general, how much information
one can receive depends on the background knowledge of the receiver. The
difference in cost different investors are willing to pay for information and
the difference in background knowledge about a particular information causes
the heterogeneity in information processing by the investment public, which is
the main reason of the price and volume patterns observed in the market. Many
assumptions in some of the recent models on behavioral finance can be derived
naturally from this theory.
|
[
{
"version": "v1",
"created": "Wed, 7 Dec 2005 17:33:51 GMT"
},
{
"version": "v2",
"created": "Thu, 22 Dec 2005 18:59:59 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Chen",
"Jing",
""
]
] |
new_dataset
| 0.995496 |
cs/0601006
|
Fady Alajaji
|
Y. Zhong, F. Alajaji and L. L. Campbell
|
On the Joint Source-Channel Coding Error Exponent for Discrete
Memoryless Systems: Computation and Comparison with Separate Coding
|
Technical Report, December 2005
| null | null | null |
cs.IT math.IT
| null |
We investigate the computation of Csiszar's bounds for the joint
source-channel coding (JSCC) error exponent, E_J, of a communication system
consisting of a discrete memoryless source and a discrete memoryless channel.
We provide equivalent expressions for these bounds and derive explicit formulas
for the rates where the bounds are attained. These equivalent representations
can be readily computed for arbitrary source-channel pairs via Arimoto's
algorithm. When the channel's distribution satisfies a symmetry property, the
bounds admit closed-form parametric expressions. We then use our results to
provide a systematic comparison between the JSCC error exponent E_J and the
tandem coding error exponent E_T, which applies if the source and channel are
separately coded. It is shown that E_T <= E_J <= 2E_T. We establish conditions
for which E_J > E_T and for which E_J = 2E_T. Numerical examples indicate that
E_J is close to 2E_T for many source-channel pairs. This gain translates into a
power saving larger than 2 dB for a binary source transmitted over additive
white Gaussian noise channels and Rayleigh fading channels with finite output
quantization. Finally, we study the computation of the lossy JSCC error
exponent under the Hamming distortion measure.
|
[
{
"version": "v1",
"created": "Wed, 4 Jan 2006 19:26:57 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Zhong",
"Y.",
""
],
[
"Alajaji",
"F.",
""
],
[
"Campbell",
"L. L.",
""
]
] |
new_dataset
| 0.95058 |
cs/0601070
|
Misha Stepanov
|
M.G. Stepanov, M. Chertkov
|
Instanton analysis of Low-Density-Parity-Check codes in the error-floor
regime
|
5 pages, 5 figures
| null | null |
LA-UR-06-0126
|
cs.IT cond-mat.dis-nn math.IT
| null |
In this paper we develop instanton method introduced in [1], [2], [3] to
analyze quantitatively performance of Low-Density-Parity-Check (LDPC) codes
decoded iteratively in the so-called error-floor regime. We discuss statistical
properties of the numerical instanton-amoeba scheme focusing on detailed
analysis and comparison of two regular LDPC codes: Tanner's (155, 64, 20) and
Margulis' (672, 336, 16) codes. In the regime of moderate values of the
signal-to-noise ratio we critically compare results of the instanton-amoeba
evaluations against the standard Monte-Carlo calculations of the
Frame-Error-Rate.
|
[
{
"version": "v1",
"created": "Mon, 16 Jan 2006 08:08:45 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Stepanov",
"M. G.",
""
],
[
"Chertkov",
"M.",
""
]
] |
new_dataset
| 0.991151 |
cs/0602015
|
Ahmad Khoshnevis
|
Ahmad Khoshnevis and Ashutosh Sabharwal
|
On the Asymptotic Performance of Multiple Antenna Channels with Fast
Channel Feedback
|
Submitted to IEEE Transactions on Information Theory
| null | null | null |
cs.IT math.IT
| null |
In this paper, we analyze the asymptotic performance of multiple antenna
channels where the transmitter has either perfect or finite bit channel state
information. Using the diversity-multiplexing tradeoff to characterize the
system performance, we demonstrate that channel feedback can fundamentally
change the system behavior. Even one-bit of information can increase the
diversity order of the system compared to the system with no transmitter
information. In addition, as the amount of channel information at the
transmitter increases, the diversity order for each multiplexing gain increases
and goes to infinity for perfect transmitter information. The major reason for
diversity order gain is a "location-dependent" temporal power control, which
adapts the power control strategy based on the average channel conditions of
the channel.
|
[
{
"version": "v1",
"created": "Mon, 6 Feb 2006 07:29:17 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Khoshnevis",
"Ahmad",
""
],
[
"Sabharwal",
"Ashutosh",
""
]
] |
new_dataset
| 0.992155 |
cs/0602032
|
David Doty
|
David Doty, Jack H. Lutz, Satyadev Nandakumar
|
Finite-State Dimension and Real Arithmetic
|
15 pages
| null | null | null |
cs.CC cs.IT math.IT
| null |
We use entropy rates and Schur concavity to prove that, for every integer k
>= 2, every nonzero rational number q, and every real number alpha, the base-k
expansions of alpha, q+alpha, and q*alpha all have the same finite-state
dimension and the same finite-state strong dimension. This extends, and gives a
new proof of, Wall's 1949 theorem stating that the sum or product of a nonzero
rational number and a Borel normal number is always Borel normal.
|
[
{
"version": "v1",
"created": "Thu, 9 Feb 2006 00:20:30 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Doty",
"David",
""
],
[
"Lutz",
"Jack H.",
""
],
[
"Nandakumar",
"Satyadev",
""
]
] |
new_dataset
| 0.990569 |
cs/0602046
|
Martin Wainwright
|
Emin Martinian, Martin J. Wainwright
|
Analysis of LDGM and compound codes for lossy compression and binning
|
5 pages; to appear in Workshop on Information Theory and its
Applications, February 2006, San Diego
| null | null | null |
cs.IT math.IT
| null |
Recent work has suggested that low-density generator matrix (LDGM) codes are
likely to be effective for lossy source coding problems. We derive rigorous
upper bounds on the effective rate-distortion function of LDGM codes for the
binary symmetric source, showing that they quickly approach the rate-distortion
function as the degree increases. We also compare and contrast the standard
LDGM construction with a compound LDPC/LDGM construction introduced in our
previous work, which provably saturates the rate-distortion bound with finite
degrees. Moreover, this compound construction can be used to generate nested
codes that are simultaneously good as source and channel codes, and are hence
well-suited to source/channel coding with side information. The sparse and
high-girth graphical structure of our constructions render them well-suited to
message-passing encoding.
|
[
{
"version": "v1",
"created": "Mon, 13 Feb 2006 03:07:28 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Martinian",
"Emin",
""
],
[
"Wainwright",
"Martin J.",
""
]
] |
new_dataset
| 0.952635 |
cs/0602085
|
Michael Baer
|
Michael B. Baer
|
Twenty (or so) Questions: $D$-ary Length-Bounded Prefix Coding
|
12 pages, 4 figures, extended version of cs/0701012 (accepted to ISIT
2007), formerly "Twenty (or so) Questions: $D$-ary Bounded-Length Huffman
Coding"
| null | null | null |
cs.IT cs.DS math.IT
| null |
Efficient optimal prefix coding has long been accomplished via the Huffman
algorithm. However, there is still room for improvement and exploration
regarding variants of the Huffman problem. Length-limited Huffman coding,
useful for many practical applications, is one such variant, for which codes
are restricted to the set of codes in which none of the $n$ codewords is longer
than a given length, $l_{\max}$. Binary length-limited coding can be done in
$O(n l_{\max})$ time and O(n) space via the widely used Package-Merge algorithm
and with even smaller asymptotic complexity using a lesser-known algorithm. In
this paper these algorithms are generalized without increasing complexity in
order to introduce a minimum codeword length constraint $l_{\min}$, to allow
for objective functions other than the minimization of expected codeword
length, and to be applicable to both binary and nonbinary codes; nonbinary
codes were previously addressed using a slower dynamic programming approach.
These extensions have various applications -- including fast decompression and
a modified version of the game ``Twenty Questions'' -- and can be used to solve
the problem of finding an optimal code with limited fringe, that is, finding
the best code among codes with a maximum difference between the longest and
shortest codewords. The previously proposed method for solving this problem was
nonpolynomial time, whereas solving this using the novel linear-space algorithm
requires only $O(n (l_{\max}- l_{\min})^2)$ time, or even less if $l_{\max}-
l_{\min}$ is not $O(\log n)$.
|
[
{
"version": "v1",
"created": "Sat, 25 Feb 2006 19:09:11 GMT"
},
{
"version": "v2",
"created": "Thu, 6 Apr 2006 01:20:41 GMT"
},
{
"version": "v3",
"created": "Wed, 12 Apr 2006 05:39:00 GMT"
},
{
"version": "v4",
"created": "Wed, 20 Jun 2007 19:47:12 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Baer",
"Michael B.",
""
]
] |
new_dataset
| 0.998779 |
cs/0603013
|
Heide Gluesing-Luerssen
|
Heide Gluesing-Luerssen, Gert Schneider
|
On the MacWilliams Identity for Convolutional Codes
| null | null | null | null |
cs.IT math.IT math.OC
| null |
The adjacency matrix associated with a convolutional code collects in a
detailed manner information about the weight distribution of the code. A
MacWilliams Identity Conjecture, stating that the adjacency matrix of a code
fully determines the adjacency matrix of the dual code, will be formulated, and
an explicit formula for the transformation will be stated. The formula involves
the MacWilliams matrix known from complete weight enumerators of block codes.
The conjecture will be proven for the class of convolutional codes where either
the code itself or its dual does not have Forney indices bigger than one. For
the general case the conjecture is backed up by many examples, and a weaker
version will be established.
|
[
{
"version": "v1",
"created": "Thu, 2 Mar 2006 17:57:02 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Gluesing-Luerssen",
"Heide",
""
],
[
"Schneider",
"Gert",
""
]
] |
new_dataset
| 0.999012 |
cs/0603014
|
Carlos Munuera
|
C. Carvalho, C. Munuera, E. Silva, F. Torres
|
Near orders and codes
|
15 pages
| null | null | null |
cs.IT math.IT
| null |
Hoholdt, van Lint and Pellikaan used order functions to construct codes by
means of Linear Algebra and Semigroup Theory only. However, Geometric Goppa
codes that can be represented by this method are mainly those based on just one
point. In this paper we introduce the concept of near order function with the
aim of generalize this approach in such a way that a of wider family of
Geometric Goppa codes can be studied on a more elementary setting.
|
[
{
"version": "v1",
"created": "Thu, 2 Mar 2006 18:31:13 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Carvalho",
"C.",
""
],
[
"Munuera",
"C.",
""
],
[
"Silva",
"E.",
""
],
[
"Torres",
"F.",
""
]
] |
new_dataset
| 0.997152 |
cs/0603018
|
Siddharth Ray
|
Siddharth Ray, Muriel Medard and Lizhong Zheng
|
On Non-coherent MIMO Channels in the Wideband Regime: Capacity and
Reliability
| null | null | null | null |
cs.IT math.IT
| null |
We consider a multiple-input, multiple-output (MIMO) wideband Rayleigh block
fading channel where the channel state is unknown to both the transmitter and
the receiver and there is only an average power constraint on the input. We
compute the capacity and analyze its dependence on coherence length, number of
antennas and receive signal-to-noise ratio (SNR) per degree of freedom. We
establish conditions on the coherence length and number of antennas for the
non-coherent channel to have a "near coherent" performance in the wideband
regime. We also propose a signaling scheme that is near-capacity achieving in
this regime.
We compute the error probability for this wideband non-coherent MIMO channel
and study its dependence on SNR, number of transmit and receive antennas and
coherence length. We show that error probability decays inversely with
coherence length and exponentially with the product of the number of transmit
and receive antennas. Moreover, channel outage dominates error probability in
the wideband regime. We also show that the critical as well as cut-off rates
are much smaller than channel capacity in this regime.
|
[
{
"version": "v1",
"created": "Fri, 3 Mar 2006 22:41:58 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Ray",
"Siddharth",
""
],
[
"Medard",
"Muriel",
""
],
[
"Zheng",
"Lizhong",
""
]
] |
new_dataset
| 0.96102 |
cs/0603095
|
Yan-Xiu Zheng
|
Yan-Xiu Zheng and Yu T. Su
|
A Turbo Coding System for High Speed Communications
|
11 figures
| null | null | null |
cs.IT math.IT
| null |
Conventional turbo codes (CTCs) usually employ a block-oriented interleaving
so that each block is separately encoded and decoded. As interleaving and
de-interleaving are performed within a block, the message-passing process
associated with an iterative decoder is limited to proceed within the
corresponding range. This paper presents a new turbo coding scheme that uses a
special interleaver structure and a multiple-round early termination test
involving both sign check and a CRC code. The new interleaver structure is
naturally suited for high speed parallel processing and the resulting coding
system offers new design options and tradeoffs that are not available to CTCs.
In particular, it becomes possible for the decoder to employ an efficient
inter-block collaborative decoding algorithm, passing the information obtained
from termination test proved blocks to other unproved blocks. It also becomes
important to have a proper decoding schedule. The combined effect is improved
performance and reduction in the average decoding delay (whence the required
computing power). A memory (storage) management mechanism is included as a
critical part of the decoder so as to provide additional design tradeoff
between performance and memory size. It is shown that the latter has a
modular-like effect in that additional memory units render enhanced performance
due not only to less forced early terminations but to possible increases of the
interleaving depth. Depending on the decoding schedule, the degree of
parallelism and other decoding resources available, the proposed scheme admits
a variety of decoder architectures that meet a large range of throughput and
performance demands.
|
[
{
"version": "v1",
"created": "Thu, 23 Mar 2006 15:03:09 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Zheng",
"Yan-Xiu",
""
],
[
"Su",
"Yu T.",
""
]
] |
new_dataset
| 0.998562 |
cs/0603098
|
Siddharth Ray
|
Siddharth Ray, Muriel Medard and Lizhong Zheng
|
A SIMO Fiber Aided Wireless Network Architecture
| null | null | null | null |
cs.IT math.IT
| null |
The concept of a fiber aided wireless network architecture (FAWNA) is
introduced in [Ray et al., Allerton Conference 2005], which allows high-speed
mobile connectivity by leveraging the speed of optical networks. In this paper,
we consider a single-input, multiple-output (SIMO) FAWNA, which consists of a
SIMO wireless channel and an optical fiber channel, connected through
wireless-optical interfaces. We propose a scheme where the received wireless
signal at each interface is quantized and sent over the fiber. Though our
architecture is similar to that of the classical CEO problem, our problem is
different from it. We show that the capacity of our scheme approaches the
capacity of the architecture, exponentially with fiber capacity. We also show
that for a given fiber capacity, there is an optimal operating wireless
bandwidth and an optimal number of wireless-optical interfaces. The
wireless-optical interfaces of our scheme have low complexity and do not
require knowledge of the transmitter code book. They are also extendable to
FAWNAs with large number of transmitters and interfaces and, offer adaptability
to variable rates, changing channel conditions and node positions.
|
[
{
"version": "v1",
"created": "Sat, 25 Mar 2006 00:46:44 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Ray",
"Siddharth",
""
],
[
"Medard",
"Muriel",
""
],
[
"Zheng",
"Lizhong",
""
]
] |
new_dataset
| 0.994208 |
cs/0604005
|
Sergio Servetto
|
Sergio D. Servetto (Cornell University)
|
Multiterminal Source Coding with Two Encoders--I: A Computable Outer
Bound
|
Submitted to the IEEE Transactions on Information Theory; Revised,
November 2006. Substantial revision after the first round of reviews
| null | null | null |
cs.IT math.IT
| null |
In this first part, a computable outer bound is proved for the multiterminal
source coding problem, for a setup with two encoders, discrete memoryless
sources, and bounded distortion measures.
|
[
{
"version": "v1",
"created": "Mon, 3 Apr 2006 04:44:33 GMT"
},
{
"version": "v2",
"created": "Mon, 8 May 2006 22:12:18 GMT"
},
{
"version": "v3",
"created": "Wed, 15 Nov 2006 05:32:28 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Servetto",
"Sergio D.",
"",
"Cornell University"
]
] |
new_dataset
| 0.97277 |
cs/0604049
|
Vignesh Sethuraman
|
Vignesh Sethuraman, Bruce Hajek
|
Low SNR Capacity of Fading Channels with Peak and Average Power
Constraints
|
13 pages, version without proofs submitted to ISIT 2006
| null | null | null |
cs.IT math.IT
| null |
Flat-fading channels that are correlated in time are considered under peak
and average power constraints. For discrete-time channels, a new upper bound on
the capacity per unit time is derived. A low SNR analysis of a full-scattering
vector channel is used to derive a complimentary lower bound. Together, these
bounds allow us to identify the exact scaling of channel capacity for a fixed
peak to average ratio, as the average power converges to zero. The upper bound
is also asymptotically tight as the average power converges to zero for a fixed
peak power.
For a continuous time infinite bandwidth channel, Viterbi identified the
capacity for M-FSK modulation. Recently, Zhang and Laneman showed that the
capacity can be achieved with non-bursty signaling (QPSK). An additional
contribution of this paper is to obtain similar results under peak and average
power constraints.
|
[
{
"version": "v1",
"created": "Tue, 11 Apr 2006 23:02:57 GMT"
},
{
"version": "v2",
"created": "Thu, 13 Apr 2006 03:40:27 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Sethuraman",
"Vignesh",
""
],
[
"Hajek",
"Bruce",
""
]
] |
new_dataset
| 0.990444 |
cs/0604085
|
Gayathre Krishnan
|
Gayathre Krishnan
|
Information in Quantum Description and Gate Implementation
|
4 pages
| null | null | null |
cs.IT math.IT
| null |
This note considers Kak's observer-reference model of quantum information,
where it is shown that qubits carry information that is sqrt n / ln n times
classical information, where n is the number of components in the measurement
system, to analyze information processing in quantum gates. The obverse side of
this exponential nature of quantum information is that the computational
complexity of implementing unconditionally reliable quantum gates is also
exponential.
|
[
{
"version": "v1",
"created": "Fri, 21 Apr 2006 16:36:45 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Krishnan",
"Gayathre",
""
]
] |
new_dataset
| 0.983916 |
cs/0605005
|
Ruoheng Liu
|
Ruoheng Liu, Ivana Maric, Roy D. Yates, and Predrag Spasojevic
|
The Discrete Memoryless Multiple Access Channel with Confidential
Messages
|
1 figure, accepted by ISIT 2006 conference
| null | null | null |
cs.IT math.IT
| null |
A multiple-access channel is considered in which messages from one encoder
are confidential. Confidential messages are to be transmitted with perfect
secrecy, as measured by equivocation at the other encoder. The upper bounds and
the achievable rates for this communication situation are determined.
|
[
{
"version": "v1",
"created": "Mon, 1 May 2006 21:19:29 GMT"
},
{
"version": "v2",
"created": "Sat, 17 Feb 2007 20:28:23 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Liu",
"Ruoheng",
""
],
[
"Maric",
"Ivana",
""
],
[
"Yates",
"Roy D.",
""
],
[
"Spasojevic",
"Predrag",
""
]
] |
new_dataset
| 0.97752 |
cs/0605014
|
Yingbin Liang
|
Yingbin Liang and H. Vincent Poor
|
Generalized Multiple Access Channels with Confidential Messages
|
Submitted to IEEE Transactions on Information Theory, April 2006
| null | null | null |
cs.IT math.IT
| null |
A discrete memoryless generalized multiple access channel (GMAC) 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. The two users are allowed to receive
channel outputs, and hence may obtain the confidential information sent by each
other from channel outputs they receive. However, each user views the other
user as a wire-tapper, and wishes to keep its confidential information as
secret as possible from the other user. The level of secrecy of the
confidential information is measured by the equivocation rate, i.e., the
entropy rate of the confidential information conditioned on channel outputs at
the wire-tapper. The performance measure of interest for the GMAC with
confidential messages is the rate-equivocation tuple that includes the common
rate, two private rates and two equivocation rates as components. The set that
includes all these achievable rate-equivocation tuples is referred to as the
capacity-equivocation region. The GMAC with one confidential message set is
first studied, where only one user (user 1) has private (confidential)
information for the destination. Inner and outer bounds on the
capacity-equivocation region are derived, and the capacity-equivocation are
established for some classes of channels including the Gaussian GMAC.
Furthermore, the secrecy capacity region is established, which is the set of
all achievable rates with user 2 being perfectly ignorant of confidential
messages of user 1. For the GMAC with two confidential message sets, where both
users have confidential messages for the destination, an inner bound on the
capacity-equivocation region is obtained.
|
[
{
"version": "v1",
"created": "Thu, 4 May 2006 18:33:15 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Liang",
"Yingbin",
""
],
[
"Poor",
"H. Vincent",
""
]
] |
new_dataset
| 0.997181 |
cs/0605044
|
Georg Schmidt
|
Georg Schmidt, and Vladimir R. Sidorenko
|
Linear Shift-Register Synthesis for Multiple Sequences of Varying Length
| null | null | null | null |
cs.IT math.IT
| null |
The problem of finding the shortest linear shift-register capable of
generating t finite length sequences over some field F is considered. A similar
problem was already addressed by Feng and Tzeng. They presented an iterative
algorithm for solving this multi-sequence shift-register synthesis problem,
which can be considered as generalization of the well known Berlekamp-Massey
algorithm. The Feng-Tzeng algorithm works indeed, if all t sequences have the
same length. This paper focuses on multi-sequence shift-register synthesis for
generating sequences of varying length. It is exposed, that the Feng-Tzeng
algorithm does not always give the correct solution in this case. A modified
algorithm is proposed and formally proved, which overcomes this problem.
|
[
{
"version": "v1",
"created": "Tue, 9 May 2006 21:23:11 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Schmidt",
"Georg",
""
],
[
"Sidorenko",
"Vladimir R.",
""
]
] |
new_dataset
| 0.983471 |
cs/0605079
|
Amos Lapidoth
|
Amos Lapidoth, Shlomo Shamai, Michele Wigger
|
On the Capacity of Fading MIMO Broadcast Channels with Imperfect
Transmitter Side-Information
|
Extended version of a paper of the same title that appeared in the
Proceedings of the 43rd Annual Allerton Conference on Communication, Control,
and Computing, Sept. 28-30, 2005
| null | null | null |
cs.IT math.IT
| null |
A fading broadcast channel is considered where the transmitter employs two
antennas and each of the two receivers employs a single receive antenna. It is
demonstrated that even if the realization of the fading is precisely known to
the receivers, the high signal-to-noise (SNR) throughput is greatly reduced if,
rather than knowing the fading realization \emph{precisely}, the trasmitter
only knows the fading realization \emph{approximately}. The results are general
and are not limited to memoryless Gaussian fading.
|
[
{
"version": "v1",
"created": "Wed, 17 May 2006 22:29:44 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Lapidoth",
"Amos",
""
],
[
"Shamai",
"Shlomo",
""
],
[
"Wigger",
"Michele",
""
]
] |
new_dataset
| 0.997582 |
cs/0605084
|
Yingbin Liang
|
Yingbin Liang and H. Vincent Poor
|
The Generalized Multiple Access Channel with Confidential Messages
|
To appear in the Proceedings of the 2006 IEEE International Symposium
on Information Theory, Seattle, WA, July 9 - 14, 2006
| null | null | null |
cs.IT math.IT
| null |
A discrete memoryless generalized multiple access channel (GMAC) 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 multiple
access channel (MAC) in that the two users also receive channel outputs. It is
assumed that each user views the other user as a wire-tapper, and wishes to
keep its confidential information as secret as possible from the other user.
The level of secrecy of the confidential information is measured by the
equivocation rate. The performance measure of interest is the rate-equivocation
tuple that includes the common rate, two private rates and two equivocation
rates as components. The set that includes all achievable rate-equivocation
tuples is referred to as the capacity-equivocation region. For the GMAC with
one confidential message set, where only one user (user 1) has private
(confidential) information for the destination, inner and outer bounds on the
capacity-equivocation region are derived. The secrecy capacity region is
established, which is the set of all achievable rates with user 2 being
perfectly ignorant of confidential messages of user 1. Furthermore, the
capacity-equivocation region and the secrecy capacity region are established
for the degraded GMAC with one confidential message set. For the GMAC with two
confidential message sets, where both users have confidential messages for the
destination, inner bounds on the capacity-equivocation region and the secrecy
capacity region are obtained.
|
[
{
"version": "v1",
"created": "Fri, 19 May 2006 05:02:09 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Liang",
"Yingbin",
""
],
[
"Poor",
"H. Vincent",
""
]
] |
new_dataset
| 0.995476 |
cs/0605105
|
Chandra Nair
|
Chandra Nair, Abbas El Gamal
|
An outer bound to the capacity region of the broadcast channel
|
12 pages, 1 figure ISIT 2006
| null | null | null |
cs.IT math.IT
| null |
An outer bound to the capacity region of the two-receiver discrete memoryless
broadcast channel is given. The outer bound is tight for all cases where the
capacity region is known. When specialized to the case of no common
information, this outer bound is contained in the Korner-Marton outer bound.
This containment is shown to be strict for the binary skew-symmetric broadcast
channel. Thus, this outer bound is in general tighter than all other known
outer bounds on the discrete memoryless broadcast channel.
|
[
{
"version": "v1",
"created": "Wed, 24 May 2006 14:40:45 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Oct 2006 16:58:27 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Nair",
"Chandra",
""
],
[
"Gamal",
"Abbas El",
""
]
] |
new_dataset
| 0.968686 |
cs/0606051
|
Shu-Tao Xia
|
Shu-Tao Xia, Fang-Wei Fu
|
Minimum Pseudo-Weight and Minimum Pseudo-Codewords of LDPC Codes
|
17 pages, 1 figure
| null | null | null |
cs.IT math.IT
| null |
In this correspondence, we study the minimum pseudo-weight and minimum
pseudo-codewords of low-density parity-check (LDPC) codes under linear
programming (LP) decoding. First, we show that the lower bound of Kelly,
Sridhara, Xu and Rosenthal on the pseudo-weight of a pseudo-codeword of an LDPC
code with girth greater than 4 is tight if and only if this pseudo-codeword is
a real multiple of a codeword. Then, we show that the lower bound of Kashyap
and Vardy on the stopping distance of an LDPC code is also a lower bound on the
pseudo-weight of a pseudo-codeword of this LDPC code with girth 4, and this
lower bound is tight if and only if this pseudo-codeword is a real multiple of
a codeword. Using these results we further show that for some LDPC codes, there
are no other minimum pseudo-codewords except the real multiples of minimum
codewords. This means that the LP decoding for these LDPC codes is
asymptotically optimal in the sense that the ratio of the probabilities of
decoding errors of LP decoding and maximum-likelihood decoding approaches to 1
as the signal-to-noise ratio leads to infinity. Finally, some LDPC codes are
listed to illustrate these results.
|
[
{
"version": "v1",
"created": "Mon, 12 Jun 2006 05:12:10 GMT"
},
{
"version": "v2",
"created": "Sat, 11 Nov 2006 14:07:48 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Xia",
"Shu-Tao",
""
],
[
"Fu",
"Fang-Wei",
""
]
] |
new_dataset
| 0.985764 |
cs/0606074
|
Yingbin Liang
|
Yingbin Liang and Gerhard Kramer
|
Rate Regions for Relay Broadcast Channels
|
Submitted to the IEEE Transactions on Information Theory, June 2006
| null | null | null |
cs.IT math.IT
| null |
A partially cooperative relay broadcast channel (RBC) is a three-node network
with one source node and two destination nodes (destinations 1 and 2) where
destination 1 can act as a relay to assist destination 2. Inner and outer
bounds on the capacity region of the discrete memoryless partially cooperative
RBC are obtained. When the relay function is disabled, the inner and outer
bounds reduce to new bounds on the capacity region of broadcast channels. Four
classes of RBCs are studied in detail. For the partially cooperative RBC with
degraded message sets, inner and outer bounds are obtained. For the
semideterministic partially cooperative RBC and the orthogonal partially
cooperative RBC, the capacity regions are established. For the parallel
partially cooperative RBC with unmatched degraded subchannels, the capacity
region is established for the case of degraded message sets. The capacity is
also established when the source node has only a private message for
destination 2, i.e., the channel reduces to a parallel relay channel with
unmatched degraded subchannels.
|
[
{
"version": "v1",
"created": "Thu, 15 Jun 2006 14:41:12 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Liang",
"Yingbin",
""
],
[
"Kramer",
"Gerhard",
""
]
] |
new_dataset
| 0.99552 |
cs/0607021
|
Jun Chen
|
Jun Chen, Da-ke He, and Ashish Jagmohan
|
Slepian-Wolf Code Design via Source-Channel Correspondence
|
to appear at ISIT 2006
| null | null | null |
cs.IT math.IT
| null |
We consider Slepian-Wolf code design based on LDPC (low-density parity-check)
coset codes for memoryless source-side information pairs. A density evolution
formula, equipped with a concentration theorem, is derived for Slepian- Wolf
coding based on LDPC coset codes. As a consequence, an intimate connection
between Slepian-Wolf coding and channel coding is established. Specifically we
show that, under density evolution, design of binary LDPC coset codes for
Slepian-Wolf coding of an arbitrary memoryless source-side information pair
reduces to design of binary LDPC codes for binary-input output-symmetric
channels without loss of optimality. With this connection, many classic results
in channel coding can be easily translated into the Slepian-Wolf setting.
|
[
{
"version": "v1",
"created": "Thu, 6 Jul 2006 22:14:47 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Chen",
"Jun",
""
],
[
"He",
"Da-ke",
""
],
[
"Jagmohan",
"Ashish",
""
]
] |
new_dataset
| 0.995415 |
cs/0607068
|
Felice Manganiello
|
Felice Manganiello
|
Computation of the Weight Distribution of CRC Codes
|
16 pages, 1 figure, submitted for publication
| null | null | null |
cs.IT math.AC math.IT
| null |
In this article, we illustrate an algorithm for the computation of the weight
distribution of CRC codes. The recursive structure of CRC codes will give us an
iterative way to compute the weight distribution of their dual codes starting
from just some ``representative'' words. Thanks to MacWilliams Theorem, the
computation of the weight distribution of dual codes can be easily brought back
to that of CRC codes. This algorithm is a good alternative to the standard
algorithm that involves listing every word of the code.
|
[
{
"version": "v1",
"created": "Thu, 13 Jul 2006 17:24:20 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Manganiello",
"Felice",
""
]
] |
new_dataset
| 0.995627 |
cs/0607074
|
Xiaohong Peng
|
Xiao-Hong Peng and Paddy Farrell
|
On Construction of the (24,12,8) Golay Codes
|
To appear in IEEE Trans. on Information Theory Vol. 24 No. 8
| null | null | null |
cs.IT math.IT
| null |
Two product array codes are used to construct the (24, 12, 8) binary Golay
code through the direct sum operation. This construction provides a systematic
way to find proper (8, 4, 4) linear block component codes for generating the
Golay code, and it generates and extends previously existing methods that use a
similar construction framework. The code constructed is simple to decode.
|
[
{
"version": "v1",
"created": "Fri, 14 Jul 2006 18:39:36 GMT"
}
] | 2007-07-13T00:00:00 |
[
[
"Peng",
"Xiao-Hong",
""
],
[
"Farrell",
"Paddy",
""
]
] |
new_dataset
| 0.999603 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.