Sociedade Brasileira de Telecomunicações · desde 1983 secretaria@sbrt.org.br
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ITS2010 · 2010

VII International Telecommunications Symposium

126 artigos · página 1 de 13
DOI 10.14209/sbrt.2010.96

Correcting Erasures and Errors in Random Network Coding

Ernst M. Gabidulin, Nina I. Pilipchuk, Martin Bossert
Rank-metric codes in matrix representation are used by Koetter, Kschischang, Silva in their theory of random network coding. They showed that the decoding procedure can be reduced to decoding of rank codes. In this paper, we analyzed situations under different conditions at the decoder and establish if there are errors only or some type of mixture of...
matrix rank codevector rank coderandom rank errorrank row erasurerank column erasurenetwork codingfast decoding algorithm
DOI 10.14209/sbrt.2010.1

Rank codes – the State of Art

Ernst M. Gabidulin
The State of Art for rank codes is presented. The theory and applications are considered.
rank metricmatrix rank codevector rank coderandom rank errorrank row erasurerank column erasurefast decoding algorithmspace-time codenetwork codingpublic-key cryptography
DOI 10.14209/sbrt.2010.97

Control in Trellis Codes produced by Finite State Machines with Information Group Zp

Jorge Pedraza Arpasi
A trellis code is the image of a signal mapper from a time invariant group code produced by a Finite State Machine, FSM. Group codes can be described as dynamical systems and good group codes must be necessarily well behaved dynamical systems. For instance good group codes must be controllable and observable, among other properties of well-behaved...
Trellis codesdynamical systemscontrollabilityp-groups
DOI 10.14209/sbrt.2010.99

Electromagnetic Interference Simulation of a Cell Phone in an Aircraft System Using Domain Decomposition Method

Juliano F. Mologni, Mateus Bonadiman, Leandro Percebon, Cesareo L. R. Siqueira, Marco A. R. Alves, Filipe Braumgratz, Edson Fonseca
Laboratorial experiments to investigate the behavior of numerous embedded avionics installations to onboard electromagnetic interference (EMI) are extremely complex and costly. Even if all electronic subsystems in an aircraft are validated under the electromagnetic compatibility (EMC) standards, the integration between them can create numerous...
Domain Decomposition Method (DDM)Electromagnetic couplingElectromagnetic Interference (EMI)Electromagnetic Compatibility (EMC)Finite Element Method (FEM)Electromagnetic radiation effects
DOI 10.14209/sbrt.2010.2

Capacity of CSMA under Nakagami Fading

Elvio J. Leonardo, Michel D. Yacoub
This paper investigates the throughput performance of carrier sense multiple access (CSMA) in a packet radio network and Nakagami fading environment. The approach considered includes the signal capture model with incoherent addition of interfering signals. The cases of uniform attenuation for all terminals (or perfect power control) as well as...
Wireless communicationCSMANakagami fading
DOI 10.14209/sbrt.2010.3

Ascending chain of semigroup rings and encoding

Tariq Shah, Atlas Khan, Antonio Aparecido de Andrade
Let B be any finite commutative ring with identity. · · · ⊂ B[X; 1ak Z0] · · · ⊂ B[X; a12 Z0] ⊂ B[X; a1 Z0], where a ∈ {2, 3, 5, 7, · · ·}, k ≥ 1, is the descending chain of commutative semigroup rings. All these semigroup rings are containing the polynomial ring B[X; Z0]. In this paper initially we introduced the construction technique of cyclic codes...
Semigroup ringBCH codealternant codeGoppa codeSrivastava code
DOI 10.14209/sbrt.2010.4

A New Model for VoIP Traffic Generation

Carlos Ignacio de Mattos, Eduardo Parente Ribeiro, Carlos Marcelo Pedroso
In this work a new model for VoIP traffic generation is proposed. The innovation of this model consists in modeling the user behavior instead of the aggregated traffic. We have analyzed the call holding time and the time interval between calls to characterize the user behavior. In order to provide an accurate packet generation, the data nature was...
Traffic ModelsVoice over IPVoice Codecs
DOI 10.14209/sbrt.2010.5

Mobile Station Location using Genetic Algorithm Optimized Radio Frequency Fingerprinting

Rafael Saraiva Campos, Lisandro Lovisolo
Radio Frequency Fingerprinting estimates the mobile station location by comparing a measured radio frequency fingerprint with a set of previously collected or generated reference fingerprints. This set is referred to as the search or correlation space. Genetic algorithms can be used to optimize both the location accuracy and the time required to...
Mobile Station LocationRadio Frequency FingerprintsPropagation ModelingGenetic AlgorithmsFirst Generation PopulationCorrelation Space
DOI 10.14209/sbrt.2010.6

A Traffic Policing Mechanism for Wimax Systems Based on Multifractal Modeling

Josemar A. Santos Jr, Flávio G. C. Rocha, Flávio H. T. Vieira
In this paper, we analyze the queueing performance in terms of loss rate of an OFDM (Orthogonal FrequencyDivision Multiplexing)/TDMA(Time Division Multiplexing Access) based Wimax system taking into account the multifractal behavior of the wireless traffic flows. To this end, first, we show evidences of multifractal characteristics on wireless...
Multifractal TrafficIEEE 802.16Policing algorithmsWireless Traffic
DOI 10.14209/sbrt.2010.100

Vertical Handoff Algorithms for Heterogeneous 3G Networks

Leandro Bento Sena Marques, Shusaburo Motoyama
One of main challenges of fourth generation wireless networks (4G) will be the integration of various mobile technologies such as CDMA 1xEV-DO RA, UMTS/HSDPA and WiMAX. In this paper, the interoperability between the CDMA 1xEV-DO RA and the UMTS/HSDPA in the 4G context is investigated. New algorithms for vertical handoff traffic acceptance are...
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