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Wyniki wyszukiwania dla: VEHICLE-TO-VEHICLE COMMUNICATIONS
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Application of Maximum-Length Sequences to impulse response measurement of hydroacoustic communications systems
PublikacjaThere is a growing interest in digital transmission of telemetry data on ultrasonic waves. The dependence of signal attenuation on squared frequency, specific to the hy-droacoustic systems, induces problems that do not exist in monochromatic, narrowband radio communications systems. For adapting the transmission parameters to current propagation conditions, a precise knowledge of instantaneous changes of channel performances is...
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Ekonomiczne aspekty zastosowania techniki Mobilnych Pomiarów Satelitarnych przy regulacji osi toru
PublikacjaOd 2009 roku interdyscyplinarny zespół naukowy Politechniki Gdańskiej i Akademii Marynarki Wojennej (a obecnie Akademii Morskiej w Gdyni) rozwija technikę Mobilnych Pomiarów Satelitarnych toru kolejowego. Technika ta polega na objeździe trasy ciągnikiem szynowym z przyczepą (wagonem-platformą) lub wózkami, z zainstalowanymi na tych pojazdach odbiornikami sygnałów satelitarnych. Umożliwia ona precyzyjne określenie współrzędnych...
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System Loss in UWB Off-Body Communications in a Ferry Environment
PublikacjaIn this paper, the system loss in UWB off-body communications in a ferry environment based on measurements is presented. A mobile measurement set-up, consisting of WBAN nodes with UWB DWM1000 modules, was used. System loss was split into LOS and NLOS conditions. For the former, the smallest mean value, 24.4 dB, was obtained for the user approaching the fixed terminal, with the antenna on his chest, and the largest, 28.1 dB, for...
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Impact of radio wave polarisation on off-body communications in indoor environments
PublikacjaThis paper describes the measurements and the analysis of the impact of radio wave polarisation on off-body communications in Body Area Networks in indoor environments. Measurements on polarisation impact are briefly described. Five investigated scenarios with different body postures and different antenna placements are characterised. The difference between the vertical and horizontal components of the received radio signal are...
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Study on the Positioning Accuracy of GNSS/INS Systems Supported by DGPS and RTK Receivers for Hydrographic Surveys
PublikacjaHydrographic surveys, in accordance with the International Hydrographic Organization (IHO) S-44 standard, can be carried out in the following five orders: Exclusive, Special, 1a, 1b and 2, for which minimum accuracy requirements for the applied positioning system have been set out. They are as follows, respectively: 1, 2, 5, 5 and 20 m, with a confidence level of 95% in twodimensional space. The Global Navigation Satellite System...
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Koncepcja zdalnego sterowania i monitoringu urządzeń trakcyjnych z wykorzystaniem technologii teleinformatycznych
PublikacjaAdvancement in wireless communication enables engineers to apply sophisticated and relatively inexpensive technologies in new fields of industry, which were previously designated solely to wire-based solutions. One of those fields is railway transportation system. In effect of a high reliability and safety demands, this area was resistive to new technologies. Nowadays, increased security and reliability of wireless sensor networks...
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Nowa metoda diagnostyki stanu technicznego nakładek stykowych
PublikacjaThe current collection system, which consists of the overhead contact line and a current collector, is particularly important in electric rail vehicles, where their reliability is concerned. Faultless current collection is conditioned not only by suitable construction of these elements but also by their proper maintenance. Retaining permanent electrical contact is essential in DC systems, where current demand is relatively high. In...
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Experimental validation of the rolling resistance measurement method including updated draft standard
PublikacjaThe main objective of ROSANNE is the harmonisation and standardisation of the measurement of skid resistance, noise emission and rolling resistance of road pavements. Regarding rolling resistance characterisation, a draft for standardization of a harmonized procedure for classification of road surfaces across Europe has been prepared within WP3 (deliverable 3.5). The procedure deals with the direct measurement on real roads of...
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Testing OFDM Transmission Schemes for Shallow Water Acoustic Communications
PublikacjaLarge variability of communication properties of underwater acoustic channels, and especially strongly varying instantaneous conditions in shallow waters, is a tough challenge for the designers of underwater acoustics communication (UAC system. There is a need for developing adaptive signaling schemes that would dynamically optimize signal parameters in both physical and link layers of communication protocols. The orthogonal frequency...
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NetBaltic System-Heterogenous Wireless Network for Maritime Communications
PublikacjaIn case of maritime communications, we observe a growing interest in deployment of multitask satellite-based solutions and development of new maritime-specific systems intended for improvements in safety of e-navigation. Analysis of different types of currently used maritime communication systems leads, however, to a conclusion that neither global and still very expensive satellite systems nor cheaper, but short-ranged transmission...
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Measurement and Analysis of the Radio Wave Polarisation in Off-Body Communications in Indoor Environment
PublikacjaThe paper describes an analysis of the radio wave polarisation in off-body communications in indoor environment. The measurement stand for polarisation measurements has been shortly described. Five investigated scenarios with different body postures and different antenna placements have been characterize. The vertical and horizontal components of received radio signal have been analysed. The measure used in analysis is a ratio...
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Badanie i analiza właściwości szerokopasmowej sieci dostępowej C-MUX firmy Marconi Communications
PublikacjaPrzeanalizowano właściwości szerokopasmowej sieci dostępowej C-MUX firmy Marconi Communications i opracowano szczegółową metodologię badań. Przedstawiono i omówiono wyniki badań sieci C-MUX i opracowano wnioski szczegółowe.
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The Impact of Information and Communications Technology on the Rise of Urban Social Movements in Poland
PublikacjaThe chapter examines the relationship between the use of Information and Communications Technology (ITC) and the emergence of social movements focused on urban agenda in Poland. The aim is to investigate how and to what extent a growing body of smaller activist groups use opportunities provided by the ITC to achieve their political objectives. The research results indicate that Web-based media have helped to raise the profile of...
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Poroelastic Road Surfaces - State of The Art
PublikacjaPoroelastic Road Surfaces (PERS) constitute a specific group of pavements containing a great amount of crumbled rubber. In most cases rubber aggregate constitutes about 20% of the mixture (by weight) and a polyurethane resin is used as a binder. As a result, PERS is characterized by a much higher elasticity than asphalt and a high porosity typical for drainage pavements. Due to this, tire/road noise is greatly reduced and on top...
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Combined environmental testing device for picosatellites
PublikacjaAs access to space conditions becomes more available, both technically and economically, scientists’ interest in launching finer and more sophisticated experiments grows. To be qualified for launch, such experiments need to be carefully tested prior to the event. The tests should represent actual launch conditions as closely and in a detailed manner. Typical tests for payload include: vibration tests, thermal and vacuum tests,...
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Non-Satellite Broadband Maritime Communications for e-Navigation Services
PublikacjaThe development of broadband network access technologies available to users on land has triggered a rapid expansion of a diverse range of services provided by terrestrial networks. However, due to limitations of digital communication technologies in the off-shore area, the maritime ICT systems evolution so far has not followed that trend. Despite the e-navigation initiative defining the set of Maritime Services, the progress in...
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Maritime Communications Network Development Using Virtualised Network Slicing of 5G Network
PublikacjaThe paper presents the review on perspectives of maritime systems development at the context of 5G systems implementation and their main properties. Firstly, 5G systems requirements and principles are discussed, which can be important for maritime applications. Secondly, the problems of network softwarisation, virtualisation and slicing, and possible types of services for potential implementation in 5G marine applications are described....
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Novel applications of noise in sensing and communications
PublikacjaPrzedstawiono zaproponowane w ostatnich latach sposoby wykorzystania szumów do wykrywania gazów, jako źródła informacji o atmosferze otaczającej czujnik. Ponadto, przedstawiono możliwości wykorzystania zjawisk losowych do bezpiecznej komunikacji.
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A Compact Circularly Polarized Antenna With Directional Pattern for Wearable Off-Body Communications
PublikacjaThis letter presents a geometrically simple and compact circularly polarized (CP) antenna with unidirectional radiation characteristics for off-body communications. The proposed antenna is based on a microstrip line monopole extension from a coplanar waveguide (CPW) and a protruded stub from one side of the coplanar ground plane along the length of the monopole. The orthogonal components of equal amplitudes required for circular...
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Simulation of Direct-Sequence Spread Spectrum Data Transmission System for Reliable Underwater Acoustic Communications
PublikacjaUnderwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. It is a particularly difficult task in a shallow underwater channel in which the signal suffers from strong time dispersion due to multipath propagation and refraction phenomena. The direct-sequence spread spectrum technique (DSSS) applied successfully in the latest standards...
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M2M communications system proposal for maritime applications
PublikacjaThis article describes the proposal to use the M2M communication to enhance the safety of people, ships and other marine infrastructure, in broadly defined marine systems. In addition, there are numerous examples of planned solutions to be implemented in the near future as well as new services. The proposal for M2M communication system architecture is described below. In addition, the use of the STRUGA system radio interface as...
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OFDM modulation and adaptive equalisation for underwater communications.
PublikacjaWłasności transmisyjne płytkiego kanału podwodnego są ograniczone ze względu na wielokrotne odbicia fal dźwiękowych od dna i powierzchni wody oraz ze względu na niestacionarność powodowaną głównie przez ruch powierzchni wody. W celu minimalizacji wpływu interferencji międzysymbolowych, powodowanych przez wielodrogową propagację fal dźwiękowych, w tradycyjnych wąskopasmowych modemach telekomunikacyjnych stosowane są złożone equalizery...
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Quality of Resilience in IP-based Future Internet Communications
PublikacjaInternet Przyszłości (zwany również Internetem 3.0 czy też NGN) jest następnym krokiem ewolucji Internetu. Prace badawcze związane z nową architekturą obejmują szerokie spektrum zagadnień, a zwłaszcza: architekturę sieci (protokoły), technologie sieciowe, aplikacje, itd. W tym artykule zakładamy wykorzystanie koncepcji Differentiated Services (DiffServ). W szczególności, proponujemy podejście ochrony zróżnicowanej ruchu. Jest ono...
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Communications, Multimedia, Ontology, Photonics and Internet Engineering 2012
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Considerations of Adaptive Digital Communications in Underwater Acoustic Channel
PublikacjaDown-link communication (DLC) and air transportable communication (ATAC) buoys as well as autonomous underwater vehicles (AUV) use acoustic links for gathering oceanographic data from underwater monitoring systems. The underwater channel propagation conditions are diverse in nature and require a special adaptive approach to the communication system design. The article presents a methodology for the communication systems design,...
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Underwater Acoustic Communications in Time-Varying Dispersive Channels
PublikacjaUnderwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. However, the bit rate achieved in UAC systems is much lower than for wire or radio-communication systems. This is due to disadvantageous properties of the UAC channels, namely the sea and inland waters. Estimation of UAC channel transmission properties is possible within...
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A New Direct-Sequence Spread Spectrum Signal Detection Method for Underwater Acoustic Communications in Shallow-Water Channel
PublikacjaDirect-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method...
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Underwater acoustic communications system with error correction and synchronization coding
PublikacjaNiezawodna transmisja danych w wielodrogowym i niestacjonarnym płytkim kanale podwodnym wymaga zastosowania efektywnej techniki modulacji oraz equalizacji adaptacyjnej. W zaproponowanym artykule w systemie transmisji danych zastosowano modulację OFDM oraz equalizację adaptacyjną opartą o filtrację Kalmana. Ponadto zaimplementowano dwie techniki kodowania: FEC w celu eliminacji błędów transmisji oraz kodowanie pseudoszumowe, którego...
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Shallow-Water Acoustic Communications in Strong Multipath Propagation Conditions
PublikacjaA phenomenon that has a strong impact on signal transmission conditions in Underwater Acoustic Communication (UAC) systems is multipath propagation. As a result of multipath propagation, the transmitted signal undergoes time dispersion which results in inter-symbol interference observed on the receiving side. Time dispersion is large, especially in horizontal channels in shallow waters which significantly limits the transmission...
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Synchronization system for underwater acoustic communications using in shallow waters
PublikacjaA reliable synchronization system of the transmitted data frame has a significant impact on the efficiency of the underwater communication system. This applies in particular to communication systems dedicated to work in shallow waters, where the phenomenon of multipath permanently occurs. To overcome these difficulties, the concept of a synchronization system consisting of two broadband signals of opposite monotonicity was presented....
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Radio Channel Measurements in Body-to-Body Communications in Different Scenarios
PublikacjaThis paper presents body-to-body radio channel measurements at the 2.45 GHz band, for different body motion scenarios and on-body antenna placements, and both indoor and outdoor environments. Measurement equipment, investigated scenarios and considered environments are described, an initial analysis of results being presented. The mean path loss and the standard deviation depend on the mutual location of transmitting and receiving...
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Radio Channel Measurements in Body-to-Body Communications in Different Scenarios
PublikacjaThis paper presents body-to-body radio channel measurements at the 2.45 GHz band, for different body motion scenarios and on-body antenna placements, and both indoor and outdoor environments. Measurement equipment, investigated scenarios and considered environments are described, an initial analysis of results being presented. The mean path loss and the standard deviation depend on the mutual location of transmitting and receiving...
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Evaluation of Connectivity Gaps Impact on TCP Transmissions in Maritime Communications
PublikacjaMany organizations and research working groups, including among others IEEE, ITU, ETSI and IMO are currently working towards improvements in communication of different types of vehicles (cars, trains, planes and vessels) and upgrading utilities and services offered to their crews and passengers travelling all over the world. The paper deals with selected aspects of the TCP protocol connectivity in maritime wireless networks. The...
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Compact Dual-Polarized Corrugated Horn Antenna for Satellite Communications
PublikacjaIn this paper, a structure and design procedure of a novel compact dual-polarized corrugated horn antenna with high gain and a stable phase center for satellite communication is presented. The antenna incorporates an Ortho-Mode Transducer (OMT), a mode converter, and a corrugated structure. The compact OMT section is designed to be fed by standard WR-75 waveguides. The proposed compact design utilizes only ten corrugated slots...
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Wideband Channel Measurements for Polarised Indoor Off-Body Communications
PublikacjaThis paper presents the initial results of wideband channel measurements for polarised off-body communication at 5.8 GHz, in an indoor environment. Channel Impulse Response measurements were performed simultaneously for two orthogonal polarisations of the wearable antenna, and repeated for vertical and horizontal orientations of the off-body one. Four types of measurement scenarios were considered in order to investigate the influence...
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Radio Channel Measurements in Off-Body Communications in a Ferry Passenger Cabin
PublikacjaThis paper presents an off-body radio channel measurements in a ferry passenger cabin at 2.45 GHz band, for static sleeping scenarios with different body orientation and on-body antennas placements, and also for upper and lower sleeping berths. The measurements have been performed with two types of on-body wearable receiving antennas: FlexPIFA (flexible planar inverted F antenna), and FlexNotch (flexible adhesive-backed notch antenna)...
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Testing the Wide-Sense Stationarity of Bandpass Signals for Underwater Acoustic Communications
PublikacjaThe Underwater Acoustic Communication (UAC) systems work in communication channels characterized by a large variety of multipath propagation conditions that can additionally change over time. Designing a reliable communication system requires knowledge of the transmission parameters of the channel. There is a need for the development of adaptive signaling schemes that would dynamically optimize the signal parameters of the physical...
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Packet routing and frame length optimization in wireless mesh networks with multicast communications
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Photonics applications in astronomy, communications, industry, and high energy physics experiments 2014
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Radio Channel Measurements in 868 MHz Off-Body Communications in a Ferry Environment
PublikacjaIn this paper, a characterization of the 868 MHz off-body radio channel in BANs is presented. Measurements were carried out in a ferry environment using a specific set-up. A method for path loss using radio distance measurements (RDMs) was developed. It allows to automate the measurements process and make it independent from the variable speed of a moving person. Based on the observed path loss as a function of distance, the obtained...
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System identification theory-based estimation of underwater acoustic channel for broadband communications.
PublikacjaPłytki kanał podwodny jest niestacjonarny z powodu wielokrotnych odbić fal dźwiękowych od powierzchni wody oraz ruchu nadajnika i odbiornika systemu komunikacyjnego. Dla zapewnienia szybkiej transmisji danych niezbędna jest estymacja kanału oparta na equalizacji adaptacyjnej. W systemach komunikacji podwodnej stosowane są zazwyczaj equalizery DFE z zaimplementowanymi algorytmami najmniejszych kwadratów: LMS oraz RLS.W artykule...
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Multimedia Communications, Services and Security MCSS. 10th International Conference, MCSS 2020, Preface
PublikacjaMultimedia surrounds us everywhere. It is estimated that only a part of the recorded resources are processed and analyzed. These resources offer enormous opportunities to improve the quality of life of citizens. As a result, of the introduction of a new type of algorithms to improve security by maintaining a high level of privacy protection. Among the many articles, there are examples of solutions for improving the operation of...
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Corrigendum to “Rapid PD-L1 detection in tumors with PET using a highly specific peptide” [Biochemical and Biophysical Research Communications 483/1 (2017) 258–263]
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How it audit can help your communications branch company increase effectiveness of using it technologies and contributes to implementation of business
PublikacjaText based on the example of Cable Television Ltd. Co. in Koszalin.
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An Island of Connectedness: Intra-Insular and Inter-Regional Communications of Rab Island (North-East Adriatic, Kvarner Gulf), Croatia
PublikacjaDrawing from archaeological data on Prehistoric and Roman settlement patterns, and respective sepulchral features, just as on later historic and cartographic sources, in this contribution it will be shown how movement along with mobility influenced on and were an integral part of settlement dynamics on the island of Rab (NE Adriatic, Croatia). The employed approach sees the practice of movement as dependent on specific social...
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Optical investigation of molecular structure of sophisticated materials forphotonics. Photonics Applications in Astronomy, Communications, Industry and High Energy Physics Experiments.
PublikacjaZastosowano komplementarne metody optyczne: spektroskopię ramanowską oraz spektroskopię w podczerwieni do badania reakcji zachodzących w czasie wytwarzania polimerów hybrydowych metodą zol-żel. Otrzymane rezultaty umożliwiły uszczegółowienie opisu reakcji hydrolizy monomerów w trakcie żelowania.
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Power to the People - Role of the New Channels of Social Communications in Polish Planning Practice = Rola nowych kanałów komunikacji społeczenej w praktyce planistycznej w Polsce
Publikacjaartykuł zawiera opis koncepcji partycypacji społecznej w planowaniu jako ''kreatywnego konfliktu''. autor przeciwstawia w nim koncepcję partycypacji w planowaniu jako neutralnej i racjonalnej dyskusji, idei, w której jest ona integralnym elementem miejskiej polityki. koncepcja ta jest ilustrowana opisem doświadczeń z warszawy oraz prac komisji dialogu społecznego (kds).
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LLA : A New Anypath Routing Scheme Providing Long Path Lifetime in VANETs
PublikacjaVehicular ad-hoc networks (VANETs) are a promising solution to improve the road traffic safety, reduce the environmental pollution, or simply provide the on-board infotainment services. However, these actions are often not possible due to high mobility of vehicles causing frequent failures of VANET links. In this paper, we focus on anypath routing to improve the reliability of multihop VANET communications. In particular, the paper...
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Advanced surveillance and operational communication system employing mobile terminals
PublikacjaDistributed surveillance and operational communications system based on XMPP protocol is presented. Its architecture and assumptions leading to the depicted design are shown. Features of XMPP protocol are portrayed with the emphasis on those most important in the context of the application. Real-time multimedia transmission with the use of Jingle/XMPP extension is discussed. The use of PDA-class computers as mobile terminals is...
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Substrate Integrated Waveguide-Based Frequency-Tunable Self-Octaplexing Antenna
PublikacjaThis communication presents the first-ever substrate integrated waveguide (SIW)-based frequency-tunable self-octaplexing antenna (SOA) for wireless communication. The structure is arranged by implementing eight distinct patches with planar 50-ohm feedlines at the top of the SIW cavity, which realize eight distinct resonant frequencies. Independent tuning of each resonant frequency is achieved by incorporating appropriately allocated...