Institute of Electron Technology
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Recommendations and Regulations of the European Commission Regarding the Pan-European eCall, Journal of Telecommunications and Information Technology, 2009, nr 4
Get PDFThe paper presents the main actions conducted by the European Commission in the context of the eCall programme (the initiatives of Driving Group), the recommendations and requirements for introduction of the pan-European eCall (architecture, handling procedures, minimum set of data (MSD) content, performance criteria, etc.) as well as regulations concerning the pan-European eCall, particularly the status of the eCall project covering also the legal situation of eCall in the Member States including Poland
A Framework for Detection of Selfishness in Multihop Mobile Ad Hoc Networks, Journal of Telecommunications and Information Technology, 2009, nr 2
Get PDFThe paper discusses the need for a fully-distributed selfishness detection mechanism dedicated for multihop wireless ad hoc networks which nodes may exhibit selfish forwarding behavior. The main contribution of this paper is an introduction to a novel approach for detecting and coping with the selfish nodes. Paper describes a new framework based on Dempster-Shafer theory-based selfishness detection framework (DST-SDF) with some mathematical background and simulation analysis
DiffServ Aware MPLS Traffic Engineering for ISP Networks: State of the Art and New Trends, Journal of Telecommunications and Information Technology, 2009, nr 1
Get PDFIn the recent ten years, with the development of new applications through Internet such as multimedia or networked control applications, users need more and more quality of service (QoS). However, the requested QoS is not the same depending on the application. Most of the new models to manage internet traffic are based on specific QoS criteria which should be optimized. This paper presents main multiprotocol label switching (MPLS) approaches such as MPLS adaptive traffic engineering (MATE), load distribution in MPLS (LDM) and load balancing over widest disjoints paths (LBWDP) that are new models for traffic engineering. It also introduces periodic multi-step (PEMS) algorithm that adapts the offered quality depending on the class of the routed traffic
Methods of Step-Size Distribution Optimization Used in S-SSFM Simulations of WDM Systems, Journal of Telecommunications and Information Technology, 2009, nr 1
Get PDFBrief review of methods used for simulation of signal propagation in wavelength division multiplexed (WDM)links is presented. We propose two novel methods of stepsize distribution optimization used to improve symmetrized split step Fourier method (S-SSFM) numerical efficiency: presimulated local error S-SSFM (PsLE S-SSFM) and modified logarithmic (ML S-SSFM). The PsLE S-SSFM contains two stages: in the initial stage step-size distribution optimization is carried out by combining local error method and presimulation with signal spectrum averaging; in the second stage conventional SSFM is used by applying optimal step-size distribution obtained in the initial stage. The ML S-SSFMis generalization of logarithmic method proposed to suppress spurious FWM tones, in which a slope of logarithmic step-size distribution is optimized. Overall time savings exceed 50%, depending of a simulated system scenario
Multiobjective Approachto Localization in Wireless Sensor Networks, Journal of Telecommunications and Information Technology, 2009, nr 3
Get PDFWireless sensor network localization is a complex problem that can be solved using different types of methods and algorithms. Nowadays, it is a popular research topic. What becomes obvious is that there are several criteria which are essential when we consider wireless sensor networks. Our objective is to determine accurate estimates of nodes location under the constraints for hardware cost, energy consumption and computation capabilities. In this paper the application of stochastic optimization for performing localization of nodes is discussed. We describe two phase scheme that uses a combination of the trilateration method, along with the simulated annealing optimization algorithm. We investigate two variants of our technique, i.e., centralized and distributed. The attention is paid to the convergence of our algorithm for different network topologies and trade-off between its efficiency and localization accuracy
Parallel and Distributed Simulation of Ad Hoc Networks, Journal of Telecommunications and Information Technology, 2009, nr 3
Get PDFModeling and simulation are traditional methods used to evaluate wireless network design. This paper addresses issues associated with the application of parallel discrete event simulation to mobile ad hoc networks design and analysis. The basic characteristics and major issues pertaining to ad hoc networks modeling and simulation are introduced. The focus is on wireless transmission and mobility models. Particular attention is paid to the MobASim system, a Javabased software environment for parallel and distributed simulation of mobile ad hoc networks. We describe the design, performance and possible applications of presented simulation software
SOI Technology: An Opportunity for RF Designers?, Journal of Telecommunications and Information Technology, 2009, nr 4
Get PDFThis last decade silicon-on-insulator (SOI) MOS-FET technology has demonstrated its potentialities for high frequency (reaching cutoff frequencies close to 500 GHz for n-MOSFETs) and for harsh environments (high temperature, radiation) commercial applications. For RF and system-onchip applications, SOI also presents the major advantage of providing high resistivity substrate capabilities, leading to substantially reduced substrate losses. Substrate resistivity values higher than 1 kΩ cm can easily be achieved and high resistivity silicon (HRS) is commonly foreseen as a promising substrate for radio frequency integrated circuits (RFIC) and mixed signal applications. In this paper, based on several experimental and simulation results the interest, limitations but also possible future improvements of the SOI MOS technology are presented
O niektórych problemach rozwoju rynku telekomunikacyjnego w Polsce w 2008 roku. Telekomunikacja i Techniki Informacyjne, 2009, nr 1-2
Get PDFPodano krótki opis, wraz z wnioskami, rozwoju rynku telekomunikacyjnego w Polsce w 2008 roku. Zaprezentowano najważniejsze wydarzenia związane zarówno z rynkiem usług stacjonarnych, jak i mobilnych. Omówiono także politykę regulacyjną prowadzoną przez Urząd Komunikacji Elektronicznej (UKE) i politykę legislacyjną Ministerstwa Infrastruktury w tej dziedzinie