Institute of Electron Technology
Biblioteka Cyfrowa Instytutu Łączności / National Institute of Telecomunications: Digital LibraryNot a member yet
2189 research outputs found
Sort by
Design of WDM Transmission System for Medical Data Exchange , Journal of Telecommunications and Information Technology, 2014, nr 2
Get PDFThis paper describes design of the Wavelength Division Multiplexing (WDM) transmission system using Alien Wavelength channels for medical data exchange. Main purpose of such system is to develop variety of services for medical cases diagnostics in order to comply with modern standards in telemedicine. Those standards refer to photo or video data transmission produced by diagnostic devices used in radiological centers together with text data concerning medical case analysis and patient data. These features are delivered by Picture Archiving and Communication System (PACS). PACS describes intra-hospital network organization, which applies to constructing system data from raw graphical data and text information according to Digital Imaging and Communications in Medicine (DICOM) version 3.0 standard. This standard is used by authors to evaluate necessary bit rate concerning all types of services delivered by PACS and cumulative throughput of link connections between hospitals and databases. Organization of this connections in metropolitan WDM system using advantages of Alien Wavelength technique is this article the main goal. Difference between configurable and non-configurable 10 Gigabit Small Form Factor Pluggable (XFP) end devices for AlienWavelength channels are analyzed and compared with the standard approach using transponder cards
Priority Based Routing for Forest Fire Monitoring in Wireless Sensor Network, Journal of Telecommunications and Information Technology, 2014, nr 3
Get PDFRecently, forest fire monitoring system in wireless sensor networks has received much attention. The conventional scheme receives fire alert data quickly to inform about fire forest event. However, since two or more nodes may detect a fire, high priority fire detection data frequently collide. In this paper, a new forest fire monitoring system is proposed in order to reduce high priority fire detection data dropped rate, by specifying a high priority received data immediately after fire detection and just before the destruction by fire. Furthermore, the node only transmits high priority data to a node, which has a low possibility of destruction by fire for low end-to-end delay of high priority fire detection data. The simulation results show that proposed scheme can reduce high priority data dropped ratio and the end-to-end delay, and have less effect of wind direction compared with the conventional scheme
Gyrotron Technology, Journal of Telecommunications and Information Technology, 2014, nr 1
Get PDFThe article presents a microwave vacuum tube called gyrotron. Its applications, construction and principle of operation are briefly described. It is also discussed the issue of an appropriate electron beam generation and formation
Radio Channels Modeling for Adaptive Antennas Applications – Analysis of Elevation, Azimuth and Delay Spread , Journal of Telecommunications and Information Technology, 2014, nr 2
Get PDFResearch of modeling urban environment channel has been presented in this paper. Measurements were performed for 2.2 GHz band. Test environment was based on existing 3G sites. Elevation, delay and azimuth spreads were analyzed. Both theoretical channel modeling and similar tests campaign were subject for analysis in this paper. Based on radio channel modeling further investigations are presented and the adaptive antenna implementation was proposed
Cassiopeia – Towards a Distributed and Composable Crawling Platform, Journal of Telecommunications and Information Technology, 2014, nr 2
Get PDFWhen it comes to designing and implementing crawling systems or Internet robots, it is of the utmost importance to first address efficiency and scalability issues (from a technical and architectural point of view), due to the enormous size and unimaginable structural complexity of the World Wide Web. There are, however, a significant number of users for whom flexibility and ease of execution are as important as efficiency. Running, defining, and composing Internet robots and crawlers according to dynamically-changing requirements and use-cases in the easiest possible way (e.g. in a graphical, drag & drop manner) is necessary especially for criminal analysts. The goal of this paper is to present the idea, design, crucial architectural elements, Proof- of-Concept (PoC) implementation, and preliminary experimental assessment of Cassiopeia framework, i.e. an all-in-one studio addressing both of the above-mentioned aspect
Burst Ratio in Concatenated Markov-based Channels, Journal of Telecommunications and Information Technology, 2014, nr 1
Get PDFThis paper deals with the burst ratio parameter, which describes the burstiness of a packet loss observed in digital networks. It is one of the input parameters of E-model – the most widely used method of assessing conversational quality of telephony. The burst ratio is defined for one channel scenario so it can be calculated when the whole transmission path has been characterized by a single set of parameters. The main objective of the paper is to extend the burst ratio definition when the transmission path is defined as a tandem concatenation of transmission channels being described by their individual burst ratios. It is assumed that packet loss of a single channel is described by a 2-state Markov chain. The final result of the research is an equation describing the burst ratio parameter when the transmission path consists of multiple concatenated channels. The derived formula has been validated by extensive simulations
Stacjonarne urządzenia TBA-ST – do pomiaru dysponowanej pojemności akumulatorów siłowni telekomunikacyjnych – projekt SKOT. Telekomunikacja i Techniki Informacyjne, 2014, nr 3-4
Get PDFPierwsze urządzenie do pomiaru pojemności baterii akumulatorów, przeznaczone do wbudowania w układ siłowni, Instytut Łączności zaprezentował już w 2004 roku, jednak dostępne wówczas rozwiązania techniczne okazały się zbyt kosztowne. Dopiero po 2011 roku wzrost cen akumulatorów ołowiowych i kosztów pracy oraz zaostrzenie wymagań niezawodnościowych dla siłowni przyniosły zainteresowanie takim rozwiązaniem, a uzyskanie rynkowego produktu o akceptowalnej cenie umożliwiły lepsze parametry elementów, doświadczenie nabyte przy opracowaniu i eksploatacji urządzeń przenośnych (TBA150-IŁ, TBA160-IŁ, TBA30-IŁ) oraz współpraca z producentem i dostawcą systemu zasilania. Dzięki uzyskaniu dofinansowania z NCBR realizacji projektu „System kontroli rezerwy energetycznej obiektów telekomunikacyjnych – SKOT” na lata 2014/15, będzie możliwa komercjalizacja tego rozwiązania. Artykuł przybliża szczegóły techniczne urządzenia TBA-ST opracowanego w Instytucie Łączności
On IPv6 Experimentation in Wireless Mobile Ad Hoc Networks, Journal of Telecommunications and Information Technology, 2014, nr 3
Get PDFWith the growing interest towards the Internet of Things IPv6-based mobile ad hoc networks (MANETs) become a key enabling technology offering the possibility of automated, unsupervised network configuration and operation. Such a functionality calls for an accurate and reliable testing of the newly proposed solutions, which is challenging due to the dynamic, decentralized and ad hoc nature of MANETs. In this work selected topics are presented on performing IPv6 protocols experimentation in wireless, IPv6-only mobile ad hoc networks – including both simulation – and testbed-based evaluation. Based on the authors experience with the evaluation of the extended IPv6 Neighbor Discovery protocol (ND++) proposed during the course of research, the selection of an opensource simulation environment is presented and a comparison between simulation and emulation experimentation methods is provided. Benefits and drawbacks of both these methodologies for testing IPv6 solutions are depicted. Moreover, the important aspects of topology and mobility considerations are considered. Finally the authors propose a testing approach that would allow for a detailed and accurate evaluation by means of open-source, easily accessible and low-cost methodologies
Partner Selection Using Reputation Information in n-player Cooperative Games, Journal of Telecommunications and Information Technology, 2014, nr 4
Get PDFTo study cooperation evolution in populations, it is common to use games to model the individuals interactions. When these games are n-player it might be di cult to assign defection responsibility to any particular individual. In this paper the authors present an agent based model where each agent maintains reputation information of other agents. This information is used for partner selection before each game. Any agent collects information from the successive games it plays and updates a private reputation estimate of its candidate partners. This approach is integrated with an approach of variable sized population where agents are born, interact, reproduce and die, thus presenting a possibility of extinction. The results now obtained, for cooperation evolution in a population, show an improvement over previous models where partner selection did not use any reputation information. Populations are able to survive longer by selecting partners taking merely into account an estimate of others' reputations