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EN
A high extinction ratio transverse magnetic (TM)-pass plasmonic waveguide polarizer has been designed and optimized. This device exploits two parallel TiN strips embedded in a silicon dioxide cladding to cut off the transverse electric (TE) polarization state, which is either reflected or absorbed, while the TM mode can pass through the main silicon waveguide with significant low losses. Given a device of 5 μm length, an extinction ratio as high as 60.7 dB and an insertion loss of 2.23 dB were achieved at the target wavelength of 1.55 μm. To our knowledge, this extinction ratio is one of the highest values ever reported. In the wavelength of 1.45–1.59 μm, the proposed device provides an optical bandwidth of 140 nm for an extinction ratio more than 30 dB and an insertion loss less than 3 dB. This device is relatively simple and is easier to be fabricated than other architectures that are found in the literature.
EN
This paper presents a broadband Switch-Mode Power Amplifier (SMPA) using a Band-Pass Filter (BPF) at the Output Matching Network (OMN). The proposed SMPA integrates a microstrip BPF as an output impedance matching network to significantly reduce the final circuit size. The microstrip lines of the filter simultaneously play the role of filtering and impedance matching. This proposed method reduces the size of the PA and reduces the power dissipation as much as possible. The BPF is placed at the output of the circuit using microstrip lines and the RT Duroid 6006 substrate. This BPF covers a wide bandwidth ranging from 3.0 GHz to 4.4 GHz. Simulation results show 9-14 dB gain with 44 - 56.6 % drain efficiency ( DE %), and the output power of 39 – 41.3 dBm would be achieved across the frequency band from 3.0 GHz to 4.4 GHz.
EN
This article provides a thorough description of a range of non-standard application cases in which EMC laboratories can be used other than those traditionally associated with this kind of facilities. The areas covered here include investigations of: wireless and radio systems (such as IoT and broadband radio systems) also that require ultra-high operational dynamic range, emulation of interference-free and/or heavilymultipath propagation environment, shielding effectiveness of cabinets and materials (i.e. thin, light and flexible as textiles as well as heavy and thick such as building construction elements).
EN
In the article implementation of a high-speed data transmission technological demonstrator using software defined radio technology is presented. A system architecture design including asymmetric framing transmission organization, which differs from the ones used in cellular systems is described. The construction of technological demonstrator consisting of a management unit, radio unit and programmable multi-threaded software performing all the protocol and system functions are shown.
PL
W niniejszym artykule omówiono realizację demonstratora technologicznego szybkiej transmisji danych zrealizowanego w technologii radia programowalnego. Przedstawiono architekturę zaprojektowanego systemu w tym asymetryczną organizację transmisji ramkowej, która odbiega od dotychczas stosowanych w systemach komórkowych. Dodatkowo omówiono konstrukcję urządzeń prototypowych składających się z jednostki zarządzającej i urządzenia radia programowalnego oraz wielowątkowe oprogramowanie realizujące wszystkie funkcje protokolarne oraz systemowe.
PL
W artykule przedstawiono realizację demonstratora technologicznego szybkiej transmisji danych w technologii radia programowalnego. Opisano architekturę zaprojektowanego systemu w tym asymetryczną organizację transmisji ramkowej, która odbiega od dotychczas stosowanych w systemach komórkowych. Przedstawiono także konstrukcję urządzeń prototypowych składających się z jednostki zarządzającej i urządzenia radia programowalnego oraz wielowątkowe oprogramowanie realizujące wszystkie funkcje protokolarne oraz systemowe.
EN
In the article the implementation of a high-speed data transmission technological demonstrator using software defined radio technology is presented. A system architecture design including assymetric framing transmission organization, which differ from the ones used in cellular systems is described. The construction of a technological demonstrator consisting of a management unit, radio unid and a programmable multitrheaded software performing all the protocol and system functions is shown.
PL
Przedstawiono problem wysokiego tempa nowej emigracji z Polski, która od 2004 r. osiągnęła już poziom około 3 milionów, głównie młodych ludzi. Przedstawiono specyfikę nowego świata społeczeństwa informacyjnego i powstawanie internetowej Polonii, czy inter-Polonii, stanowiącej swoistą internetową wspólnotę Polaków z Polski i zza granicy oraz Polonii. Przedstawiono wyzwanie utrzymania tych osób i ich potomków w obszarze oddziaływania polskiej kultury oraz zapewnienia wszystkim zainteresowanym warunków do utrzymania ich tożsamości narodowej. Zaprezentowano wypowiedzi Świętego Jana Pawła II. Dotyczą one problemu tożsamości i dziedzictwa, aktualnego również w wirtualnym świecie oraz ocenę wymiaru etycznego sposobu wykorzystywania i korzystania z Internetu. Przedstawiono również problem zapewnienia dostępu do polskiego języka, historii i kultury potomkom tych Polaków, którzy z przyczyn od siebie niezależnych znaleźli się poza granicami współczesnej Rzeczypospolitej. Szczególnie dotyczy to potomków tych, którzy za swoją polskość byli represjonowani, a nawet masowo mordowani. Przedstawiono możliwości, jakie nowe techniki informacyjne i komunikacyjne (ICT), a zwłaszcza szerokopasmowy dostęp do Internetu, zapewniają w zakresie integracji społecznej i kulturowej środowisk przestrzennie rozproszonych. Omówiono specyfikę nowych środków technicznych, nowe możliwości i nowe ryzyka, sygnalizując również nową inicjatywę. Zaapelowano o całościową politykę państwową i przedstawiono cele dyskusji na XV KOS 2014. Potwierdzono gotowość SEP do wspierania niezbędnych działań.
EN
The article presents the problem of the high rate of new emigration of Polish citizens, which since 2004 have already reached a level of about 3 million, mostly young people. It shows the specificity of a new world Information Society, resulting in Iheformation of Internet’s "Polonia" or "Inter- Polonia", which is a kind of an Internet community of Poles from Poland and other countries and "Polonia" people, presents a challenge to maintain these people and their descendants in the area of influence of Polish culture and to ensure all interested parties, the conditions to maintain their national identity. The article presented related to this challenge, speeches of the Holy Father, Blessed and soon the Holy, Pope John Paul II. These relate to the problem of identity and heritage, current also in the virtual world, as well as evaluating the ethical dimension of Internet use. The article discuses also the problem of providing access to the Polish language, history and culture, for the descendants of those Poles who, for reasons beyond their control, find themselves outside of the contemporary Poland borders. This is especially true for descendants of those, who were victimized because of being Polish and even mass- murdered. The possibilities of what new information and communication technology (ICT), and particularly broadband Internet access, provide a range of social and cultural integration of spatially distributed Polish people. In this article are presented also the new technical possibilities, new opportunities and new risks and giving information on the new initiative. Called for a comprehensive national policy objectives and presents a discussion on the fifteenth KOS 2014. SEP confirmed readiness to support the necessary actions.
EN
The objective of the study was to carry out numerical simulation of the hydrodynamic noise generated by the flow around a non-cavitating underwater propeller. To achieve this goal, hydrodynamic simulation of flow around the propeller was initially done. The unsteady 3-D flow was modelled numerically along with the LES turbulence model. The hydrodynamic parameters calculated for different advance coefficients are visibly in line with the previous experimental works. The turbulent quantities of the hydrodynamic study and the FWH model were used to find spectral distributions of flow noise for different advance coefficients. The results of the acoustic investigation were compared against other numerical results. An array of 100 hydrophones was used to find the directional distribution of the noise around the propeller. The obtained results indicate that, for different advance coefficients, the highest intensity of the noise recorded by different receivers around the propeller occurs in BPF. Furthermore, it has been found that the noise is directionally as well as intensively distributed around the propeller. Noise distributions of noise are presented and discussed for different regimes of propeller rotation. The analysis of the expanded spectrum (broadband analysis) of noise on the propellers has also been done and the contribution of all parts of the propeller to hydrodynamic noise generation are presented.
EN
In the paper a cost-effective input block of the SDR receiver for 0.9 - 2.4GHz frequency band built of capacitivetuned selective amplifier and broadband Vivaldi antenna is presented. The applied selective amplifier consists of three identical sections of tunable filters and two stages of monolithic broadband amplifiers. The single filter section proposed by the authors, due to its ability to absorb parasitic inductances of varicap diodes, simplifies usage of encapsulated varicap diodes in design of tunable in broad band selective filters dedicated to input stages of the receivers. Moreover, proposed filter section has small variation of in-band insertion loss in comparison to varicap-tuned filters built of coupled transmission lines which are commonly applied in input blocks of the microwave receivers. The described selective amplifier could be easily integrated on a single substrate with the Vivaldi antenna which is a cost effective way of fabrication of the tunable in broad band input block of a receiver that has desired gain, selectivity and directivity of the antenna.
EN
A method of all-optical correlation is proposed using the nonlinear phenomena Four Wave Mixing (FWM) of two different signals. The method shows a serial solution where correlation of an ultrafast real-time serialized broadband source is demonstrated using a Highly Non-Linear Fibre (HNLF) with correlation rate reaching 200MHz.
EN
This paper aims to discuss the recent trends in the regulation of telecom services regarding the diffusion of broadband. To this matter, it compares the recent international competition regulation experiences to the Brazilian scenario. Considering that the telecom sector passed through huge technological and structural transformations in the last decades (from typical voice communications to convergent services based on broadband, and from voice services monopoly to multiple services oligopoly), its regulatory framework has also changed. Lately, several countries - such as the United States, the Netherlands, Korea and Chile - have established inter and intra-platform competition regulations in order to expand the access to the new forms of communications based on broadband. In Brazil, such mechanisms are not fully explored, and the country has lots of areas in which there is no competition in broadband services (known as multimedia communication services). As a result, Brazil has one of the highest prices of broadband services and one of the lowest levels of broadband penetration. In this way and considering international success in expanding services through competition, the paper defends that such mechanisms should be reinforced in the Brazilian broadband market.
11
Content available Wąbrzeźno city broadband IP network
EN
In the paper the designing project (plan) of Wąbrzeźno City broadband IP optical network has been presented. The extended version of network plan constitute technical part of network Feasibility Study, that will be implemented in Wąbrzeźno and be financed from European Regional Development Funds. The network plan presented in the paper contains both topological structure of fiber optic network as well as the active equipment for the network. In the project described in the paper it has been suggested to use Modular Cable System - MCS for passive infrastructure and Metro Ethernet technology for active equipment. The presented solution provides low cost of construction (CAPEX), ease of implementation of the network and low operating cost (OPEX). Moreover the parameters of installed Metro Ethernet switches in the network guarantee the scalability of the network for at least 10 years.
PL
W pracy przedstawiony został projekt szerokopasmowej sieci IP dla miasta Wąbrzeźna. Rozszerzona wersja projektu stanowi część techniczną Studium Wykonalności zadania, które będzie wdrażane w mieście Wąbrzeźno. Zadanie to będzie współfinansowane z funduszy Regionalnego Programu Operacyjnego. Prezentowany w pracy projekt sieci zawiera zarówno opis części pasywnej (topologia kabli optycznych), jak i części aktywnej. Dla budowy części pasywnej sieci sugeruje się wykorzystanie systemu mikrokabli. Z kolei, dla budowy części aktywnej sieci sugeruje się wykorzystanie przełączników (switchy) Metro Ethernet. Zaprezentowane w pracy rozwiązanie zapewnia niski koszt inwestycyjny (CAPEX) budowy sieci, łatwość implementacji oraz niskie koszty operacyjne (OPEX). Ponadto także parametry wydajnościowe zastosowanych w sieci przełączników Metro Ethernet zapewniają skalowalność sieci przez okres co najmniej 10 lat.
PL
IFTV to jedna z najbardziej skomplikowanych i wymagających usług realizowanych we współczesnych sieciach teleinformatycznych. Jej wdrożenie wiąże się z koniecznością spełnienia przez sieć operatora wielu wymagań dotyczących bezpieczeństwa, niezawodności, jakości, monitorowania sieci oraz zarządzania treścią. Przedstawiono architekturę sieci umożliwiającą świadczenie usługi IPTV.
EN
IPTV is one of the most complicated and demanding services being introduced in fix networks. Successful deployment of IPTV requires that aspects like security, reliability quality of service, network and content management must be thoroughly planned and tested. This article presents range of topics related with IPTV service deployment in operators' networks.
PL
W Polsce dostęp do szerokopasmowego Internetu z roku na rok jest coraz lepszy. Dla dalszego rozwoju istotne powinno być wejście w życie ustawy o wspieraniu rozwoju usług i sieci telekomunikacyjnych. W ciągu najbliższych pięciu lat ma ono umożliwić powszechny dostęp do szerokopasmowego Internetu.
EN
The development of broadband in Poland from year to year is becoming easier and more affordable. For the further development of broadband in Poland should be a significant entry into force of the Act to promote the development of telecommunications networks and services (May 7, 2010). Generally, over the next five years, the law is intended to allow Poles the universal broadband.
EN
Development 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.
PL
Przedstawiono trendy techniczne rozwoju rynku PMR/PAMR, związane z implementacją cyfrowych systemów: wąskopasmowych o paśmie rozszerzonym i szerokopasmowych. Omówiono kwestie związane z zagospodarowaniem widma, wskazano zakresy częstotliwości, jakie można będzie przeznaczyć dla potrzeb powyższych systemów.
EN
This article describes the new technology trends on PMR/PAMR market, connected with digital implementation for narrow, wide-and broad-band high speed systems. Compatibility with existing systems and spectrum management for new one has been presented. The frequency bands for the new systems have been shown.
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