Institute of Electron Technology
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Bandwidth Trading: A Comparison of the Combinatorial and Multicommodity Approach, Journal of Telecommunications and Information Technology, 2010, nr 2
Get PDFSince the telecommunication market becomes more complex and dynamic, a strong need for a new, efficient and flexible bandwidth trading mechanisms appears. We believe that good mechanisms, that allow effective and fair allocation of bandwidth between market participants will help to develop the real competitive bandwidth market. In this paper we compare two different double-sided bandwidth auction mechanisms, that seem to be well suited approaches for trading indivisible units of bandwidth: combinatorial auction c-SeBiDA and multicommodity mechanism BACBR-I. The c-SeBiDA mechanism considers two types of commodities: inter-node links and paths consisting of particular links. Market partici- pants may bid a single link, or a bundle of links, constituting a specific path. The BACBR-I mechanism is a multicommodity exchange model, that allows bidders to place buy offers not only for individual or bundled links, but rather for end-to-end connections. Therefore, it is the decision model that allocates the most efficient links to connections. We run a large set of experiments to test the allocation and computational efficiency obtained under both approaches
Stochastic Modelsin Techno-Economic Analysis of Broadband Access Networks, Journal of Telecommunications and Information Technology, 2010, nr 2
Get PDFDevelopment of networks, specially access networks, is very important and urgent task nowadays. However, it turns out that this segment of telecommunication networks is the most expensive and complicated part of this undertaking. Therefore, the thorough analyses are carried out to determine the best solution under specific circumstances before any decisions are made. This paper presents techno-economic model, which was implemented and used to carry out analyses for one of the biggest city in Poland. To take uncertainty into consideration the stochastic approach was applied providing more robust solution, therefore, improving the safety of investment. Analyses concern FTTH (fibre to the home) technology, type of generic FTTx network architecture. It uses optical fibre in local telecommunication loop, what is becoming more and more popular. Presented results show the usefulness of techno-economic surveys in planning access networks development. The appropriate choice of network parameters, such as the aggregation ratio, is essential and could significantly influence the investment profitability
Rural Telecommunications Infrastructure Selection Using the Analytic Network Process, Journal of Telecommunications and Information Technology, 2010, nr 2
Get PDFThe decisions involved in rural settings are of complex nature, with some aspects compounded by the presence of intangible criteria. Hence, a suitable approach is needed that can produce effective solutions. This paper describes the applicability of a multicriteria decision-making method, specifically the analytic network process (ANP), to model the selection of an appropriate telecommunications infrastructure technology, capable of deploying e-services in rural areas of developing countries. It aims to raise awareness among telecommunication planners about the availability of ANP, and to demonstrate its suitability to enhance the selection process. The proposed model is constructed based on concerned experts’ views of relevant selection criteria and potential technology alternatives. Its network structure caters for all possible dependencies and interactions among criteria and alternatives
Simulation Model of Biometric Authentication Using Multiagent Approach, Journal of Telecommunications and Information Technology, 2010, nr 4
Get PDFIn this article authors present the concept of application of multiagent approach in modeling biometric authentication systems. After short introduction, we present a short primer to multiagent technology. Next, we depict current state of the art related to biometrics combined with multiagent approach. In the next part of the work we present four exemplary simulation models of biometric authentication environments as well as the results of their examination
Impact of Crosstalk into High Resistivity Silicon Substrate on the RF Performance of SOI MOSFET, Journal of Telecommunications and Information Technology, 2010, nr 4
Get PDFCrosstalk propagation through silicon substrate is a serious limiting factor on the performance of the RF devices and circuits. In this work, substrate crosstalk into high resistivity silicon substrate is experimentally analyzed and the impact on the RF behavior of silicon-on-insulator (SOI) MOS transistors is discussed. The injection of a 10 V peak-to-peak single tone noise signal at a frequency of 3 MHz ( fnoisfnoise) generates two sideband tones of −56 dBm separated by fnoise from the RF output signal of a partially depleted SOI MOSFET at 1 GHz and 4.1 dBm. The efficiency of the introduction of a trap-rich polysilicon layer located underneath the buried oxide (BOX) of the high resistivity (HR) SOI wafer in the reduction of the sideband noise tones is demonstrated. An equivalent circuit to model and analyze the generation of these sideband noise tones is proposed
Systemy InHousePLC – charakterystyka ogólna, kierunki rozwoju i zastosowań. Telekomunikacja i Techniki Informacyjne, 2010, nr 3-4
Get PDFW artykule zamieszczono charakterystykę ogólną współczesnych systemów łączności elektronicznej opartych na technologii InHousePLC. Omówiono elementy składowe tych systemów, używane medium transmisyjne i wykorzystywane zakresy częstotliwości, a także stosowane metody modulacji i protokoły komunikacyjne warstwy drugiej. Scharakteryzowano zagadnienia kompatybilności elektromagnetycznej, przedstawiono głównych dostawców urządzeń składowych, a także nakreślono kierunki dalszego rozwoju i zastosowań tych systemów
Multi-Domain Modeling and Simulations of the Heterogeneous Systems, Journal of Telecommunications and Information Technology, 2010, nr 1
Get PDFThis paper discusses the multi-domain modeling and simulation issues of the design and analysis of heterogeneous integrated systems. Modeling and simulation methodology and tools are also discussed
Relaxing the WDO Assumptionin Blind Extraction of Speakers from Speech Mixtures, Journal of Telecommunications and Information Technology, 2010, nr 4
Get PDFThe time-frequency masking approach in blind speech extraction consists of two main steps: feature clustering in a space spanned over delay-time and attenuation rate, and spectrogram masking in order to reconstruct the sources. Usually a binary mask is generated under the strong W-disjoint orthogonal (WDO) assumption (disjoint orthogonal representations in the frequency domain). In practice, this assumption is most often violated leading to weak quality of reconstructed sources. In this paper we propose the WDO to be relaxed by allowing some frequency bins to be shared by both sources. As we detect instantaneous fundamental frequencies the mask creation is supported by exploring a harmonic structure of speech. The proposed method is proved to be effective and reliable in experiments with both simulated and real acquired mixtures
Computational Methodsfor Two-Level 0-1 Programming Problemsthrough Distributed Genetic Algorithms, Journal of Telecommunications and Information Technology, 2010, nr 2
Get PDFIn this paper, we consider a two-level 0-1 programming problem in which there is not coordination between the decision maker (DM) at the upper level and the decision maker at the lower level. We propose a revised computational method that solves problems related to computational methods for obtaining the Stackelberg solution. Specifically, in order to improve the computational accuracy of approximate Stakelberg solutions and shorten the computational time of a computational method implementing a genetic algorithm (GA) proposed by the authors, a distributed genetic algorithm is introduced with respect to the upper level GA, which handles decision variables for the upper level DM. Parallelization of the lower level GA is also performed along with parallelization of the upper level GA. The proposed algorithm is also improved in order to eliminate unnecessary computation during operation of the lower level GA, which handles decision variables for the lower level DM. In order to verify the effectiveness of the proposed method, we propose comparisons with existing methods by performing numerical experiments to verify both the accuracy of the solution and the time required for the computation
Pricing Rules Comparisonin the Context of Bandwidth Trade, Journal of Telecommunications and Information Technology, 2010, nr 2
Get PDFIn this paper we compare two pricing rules in the context of bandwidth trade. Allocation and pricing rules, together with a set of signals received from independent agents, constitute a market mechanism. In the paper we analyze two pricing rules: well known Vickrey-Clarke-Groves rule (VCG) and the parametric pricing rule (PPR).We apply these pricing rules to the allocation rule specified by the balancing communication bandwidth trade model (BCBT)