Institute of Electron Technology
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Instytut Łączności wobec wyzwań związanych z wdrażaniem sieci 5G w Polsce, Telekomunikacja i Techniki Informacyjne, 2018, nr 1-2
Get PDFW artykule zaprezentowano korzyści gospodarcze płynące z wdrożenia nowej generacji sieci mobilnych, tzw. sieci 5G, oraz omówiono wynikające z nich efekty społeczne, w tym spodziewany wpływ na rozwój społeczeństwa informacyjnego. Następnie przedstawiono wyzwania związane z wdrażaniem 5G w Polsce. W głównej mierze wynikają one z obecności barier o charakterze technicznym, ekonomicznym i prawnym, które mogą spowolnić proces wdrażania 5G w Polsce. W artykule przedstawiono również inicjatywy mające na celu identyfikację barier wdrażania sieci 5G oraz potencjalne sposoby ich likwidacji. W tym kontekście przedstawiono działania Instytutu Łączności na rzecz wdrażania 5G w Polsce, w tym poprzez organizację prac w kierowanym przez Ministra Cyfryzacji Porozumieniu na rzecz Strategii „5G dla Polski” oraz uczestnictwo w projekcie 5G@PL realizowanym w ramach strategicznego programu badań naukowych i prac rozwojowych „Społeczny i gospodarczy rozwój Polski w warunkach globalizujących się rynków – Gospostrateg”
Miniaturized Spectacles Shaped Tapered Slotted Patch Antenna for UWB Applications, Journal of Telecommunications and Information Technology, 2018, nr 1
Get PDFA compact planner patch ultra-wideband (UWB) antenna is presented in this paper. The antenna configuration consists of a spectacles-shaped patch and a slotted ground plane. Different parameters are investigated for improving the antenna’s properties and for achieving the preferred UWB band (3.1–10.6 GHz). The experimental and simulated results demonstrate that the proposed antenna acquires an operating bandwidth of 117% (3–11.5 GHz) with a stable omnidirectional radiation pattern, about 89% of average radiation efficiency and 4.2 dBi of average gain with the maximum of 5.7 dBi at 10.2 GHz
Interference Management using Power Control for Device-to-Device Communication in Future Cellular Network, Journal of Telecommunications and Information Technology, 2018, nr 3
Get PDFThere are many scenarios that have been proposed for fifth generation (5G) networks. Some of them, if implemented, will bring fundamental changes at the architectural and node level. One example of such proposed technologies is device-to-device (D2D) communications which will change the nature of conventional cellular network design. D2D permits direct communication between two or more user devices without intervention of the base station (i.e. eNB). D2D can ensure network performance improvement over the traditional cellular network, because it can offload the mobile data traffic from the other devices. However, applying D2D features in a cellular network will bring about more complex interference problems, since D2D communication uses the same band as its underlying cellular communication network. The aim of this research is to investigate interference-related problems caused by D2D communications, affecting the underlying cellular networks, during downlink and uplink transmissions. The paper examines the use of power control methods to mitigate interference. A comparison is offered between fixed power level (FC) with or without power control, and adaptive power controls using two methods (AC1 and AC2), on a base station or on each of the D2D devices, based on the measured signal to interference plus noise ratio (SINR). The simulation results show that both power control methods contribute to improvement of network performance. AC1 and AC2 can improve SINR by about 1 dB and 0.5 dB compared to FC in a downlink transmission, and by 0.5 dB in an uplink transmission
Theoretical Investigation of Different Diversity Combining Techniques in Cognitive Radio, Journal of Telecommunications and Information Technology, 2018, nr 3
Get PDFIn this paper, the performance of an energy detector in cognitive radio, using different diversity combining techniques, is evaluated. Among many diversity combining techniques, maximal ratio combining (MRC) gives the best results but at the cost of the highest complexity. To design a simpler receiver, it is suggested to use less complex combining techniques, i.e. switched diversity, which provides one of the least complex solutions to combat fading. The paper analyzes two switched diversity schemes, switch examine combining (SEC), and switch examine combining with post examining selection (SECp). A closed form expression determining the probability of detection using MRC, SEC and SECp is derived for various numbers of branches. Detection performance with different diversity combining techniques is compared and the complexity trade-off is observed
A CPW-fed Sigma-shaped MIMO Antenna for Ka Band and 5G Communication Applications, Journal of Telecommunications and Information Technology, 2018, nr 4
Get PDFThis article presents a MIMO compact antenna measuring 45×45×1.6 mm, on the FR4 substrate, proposed for Ka band and 5G communication applications. The proposed design is suitable to overcome the issues connected with massive MIMO. It has four-sigma-shaped radiating elements and a c-shaped ground plane with coplanar waveguide feeding. Its compact dimensions suit it for most existing communications systems. The aerial operates in the 21–30 GHz range, which covers Ka and 5G communication bands. The proposed antenna exhibits the average efficiency of more than 76% within its operating band and gives a minimum signal to noise plus interference ratio. The presented antenna covers several services, such as Ka band satellite downlink applications and future 5G communication applications
Laboratorium Oceny Cyberbezpieczeństwa Instytutu Łączności – wymagania i wytyczne, Telekomunikacja i Techniki Informacyjne, 2018, nr 1-2
Get PDFRozwój technologii telekomunikacyjnych zwiększa zapotrzebowanie na certyfikację bezpieczeństwa produktów i usług. W połączonych gospodarkach, w tym w szczególności w Unii Europejskiej, istotne znaczenie ma wzajemne uznawanie certyfikatów wydawanych na podstawie wiarygodnych i kompletnych ocen bezpieczeństwa. Obecnie jest to możliwe dzięki porozumieniom międzynarodowym, takim jak Common Criteria Recognition Agreement (CCRA) i Senior Officers Group Information Security – Mutual Recognition Agreement (SOG-IS MRA).Proces certyfikacji produktu lub usługi składa się z dwóch etapów: ewaluacji (oceny), którą wykonują laboratoria oraz wydawania certyfikatów, które wykonują jednostki certyfikujące. Laboratoria przeprowadzające ewaluację muszą spełnić szereg kryteriów, określanych przez krajowe jednostki certyfikujące. W opracowaniu przeanalizowano wymagania i praktyki laboratoriów w krajach należących do porozumień międzynarodowych, zapewniających wzajemne uznawanie certyfikatów zgodnych z Common Criteria wraz z wnioskami i wytycznymi dla Laboratorium Oceny Cyberbezpieczeństwa w Instytucie Łączności
Network Selection in Wireless Heterogeneous Networks: a Survey, Journal of Telecommunications and Information Technology, 2018, nr 4
Get PDFHeterogeneous wireless networks is a term referring to networks combining different radio access technologies with the aim of establishing the best connection possible. In this case, users with multi-mode terminals can connect via different wireless technologies, such as 802.16, 802.11, UMTS, HSPA and LTE, all at the same time. The problem consists in the selection of the most suitable from all radio access technologies available. The decision process is called network selection, and depends on several parameters, such as quality of service, mobility, cost, energy, battery life, etc. Several methods and approaches have been proposed in this context, with their objective being to offer the best QoS to the users, and/or to maximize re-usability of the networks. This paper represents a survey of the network selection methods used. Multiple attribute-dependent decision-making methods are presented. Furthermore, the game theory concept is illustrated, the use of the fuzzy logic is presented, and the utility functions defining the network selection process are discussed
An Efficient ANN Interference Cancelation for High Order Modulation over Rayleigh Fading Channel, Journal of Telecommunications and Information Technology, 2018, nr 4
Get PDFHigh order modulation (HOM) presents a key challenge in increasing spectrum efficiency in 4G and upcoming 5G communication systems. In this paper, two non-linear adaptive equalizer techniques based on multilayer perceptron (MLP) and radial basis function (RBF) are designed and applied on HOM to optimize its performance despite its high sensitivity to noise and channel distortions. The artificial neural network’s (ANN) adaptive equalizer architectures and learning methods are simplified to avoid more complexity and to ensure greater speed in symbol decision making. They will be compared with the following popular adaptive filters: least mean square (LMS) and recursive least squares (RLS), in terms of bit error rate (BER) and minimum square error (MSE) with 16, 64, 128, 256, 512 and 1024 quadrature amplitude modulation (QAM). By that, this work will show the advantage that the MLP equalizer has, in most cases, over RBF and traditional linear equalizers
Link Quality Assessment Algorithm for Heterogeneous Self-organizing Maritime Communications Network, Journal of Telecommunications and Information Technology, 2018, nr 2
Get PDFThe article introduces a method of performing a radio link quality assessment based on the Link Quality Indicator (LQI) which will be calculated for every system that is available. The method presented has been developed during the netBaltic project completed in Poland and generally applies to the so-called maritime zone A, i.e. the sea area where ships are still within the range of shore-based radio communication systems, particularly 3G/LTE cellular networks. The algorithm was developed based on the results of measurements obtained during two separate campaigns. That measurement data served as a basis for the method’s initial assumptions and was utilized during the method’s verification