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Search results for: RADIO CHANNEL MEASUREMENTS
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Radio Channel Measurements in Body-to-Body Communications in Different Scenarios
PublicationThis 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
PublicationThis 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 Off-Body Communications in a Ferry Passenger Cabin
PublicationThis 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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Radio Channel Measurements in 868 MHz Off-Body Communications in a Ferry Environment
PublicationIn 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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Tracking body movement for radio channel measurements in BAN with indoor positioning system
PublicationThis paper presents indoor positioning system based on inertial navigation with additional distance measurements using UWB modems and map matching to increase accuracy and eliminate position drift. Such system may be used to track position of human body during radio channel measurements for body area networks. Performance of proposed system and limitations caused by inertial navigation are briefly described.
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The Influence of the Radio Channel on Precision of Position Estimation of the User Terminal Using the NB-IoT Radio Interface
PublicationIn the article the method of user terminal position estimation using the broadcast signals transmitted in the downlink of the NB-IoT interface was presented, including the analysis of the radio channel influence on precision of position estimation as well as the eNodeB (Evolved Node B) synchronization. The practical ability to estimate the position in the test area has been verified in the laboratory conditions, using the reference...
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Wideband Channel Measurements for Polarised Indoor Off-Body Communications
PublicationThis 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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Measurements of High-Speed Data Transmission Radio Link for Special Applications
PublicationIn the article measurements of high-speed data transmission radio link for special applications were presented. Build measurement stand, measurement scenario and obtained results were briefly described. All conducted research work took place in real maritime environment.
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Path Loss Measurements in Wideband Radio Link Designed for Maritime Environment
PublicationIn the article, the research and analysis of path loss in designed and evaluated digital radio link for high-speed data transmission in maritime environment is presented. Collected samples of received signal were used to determine the mean path loss and its standard deviation. Measuring campaign was carried out in a real maritime conditions. The mean value of path loss reached 126 dB on a distance of 11.16 km.
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Selected properties and parameters of radio channel impulse response estimation in ISM 2.4 GHz band
PublicationThe article presents experimental research indicating that the impulse response of the communication channel, determined in practice, are not of an universal character, but only represent its approximate value for the frequency on which this measurement was made. Phases for each of the replicas of the measurement signal were determined during the analysis of the received signals in the baseband. Phase changes of individual replicas...
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Channel Impulse Response Measurements at mmWave Band in Office and Conference Rooms
PublicationIn this paper, the measurements of the channel impulse response at mmWave band in office and conference rooms are described. The central frequency is 27 GHz with a bandwidth of 400 MHz. The description of the used measurement stand and considered environments are presented. The initial analysis of the power delay profile, mean delay, and RMS delay spread allows preliminary conclusions to be drawn that there is a significant impact...
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Novel Adaptive Method for Data Streams Allocation Based on the Estimate of Radio Channel Parameters in Heterogeneous WBAN Network
PublicationThe new adaptive method for data streams allocation in heterogeneous Wireless Body Area Networks and meas-urement equipment is presented. The results obtained using the developed method compared with the selected algorithms likely to be used in those networks. The pro-posed adaptive data streams allocation method based on radio channel parameters makes it even twice as efficient to use in terms of resources usage in a WBAN heterogeneous...
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Stationary underwater channel experiment: Acoustic measurements and characteristics in the Bornholm area for model validations
PublicationThe underwater acoustical channel is time-variant, and even on small time scales there is often existing no ‘acoustical frozen ocean’. Popular is the use of WSSUS-channel transmission modeling (Wide-Sense Stationary Uncorrelated Scattering) for the stochastic description of bandpass signals in GSM mobile phones with moving participants; since this results in a halved number of model parameters. For underwater sound applications...
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[ITiT] Transmission Channel in Radio Communication Systems
e-Learning Courses{mlang pl} Dyscyplina: informatyka techniczna i telekomunikacja Zajęcia fakultatywne dla doktorantów II roku Prowadzący: dr hab. inż. Sławomir Ambroziak, prof. PG Liczba godzin: 15 Forma zajęć: wykład {mlang} {mlang en} Discipline: technical informatics and telecommunications Elective course for 2nd-year PhD students Academic teachers: dr hab. inż. Sławomir Ambroziak, prof. PG Total hours of training: 15 teaching hours Course...
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Source and Channel Coding in Radio Communication Systems
e-Learning Courses -
[ITiT] Transmission Channel in Radio Communication Systems - 2023/2024
e-Learning Courses{mlang pl} Dyscyplina: informatyka techniczna i telekomunikacja Zajęcia fakultatywne dla doktorantów II roku Prowadzący: dr hab. inż. Sławomir Ambroziak, prof. PG Liczba godzin: 15 Forma zajęć: wykład {mlang} {mlang en} Discipline: technical informatics and telecommunications Elective course for 2nd-year PhD students Academic teachers: dr hab. inż. Sławomir Ambroziak, prof. PG Total hours of training: 15 teaching hours Course...
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Source and Channel Coding in Radio Communication Systems 2023/2024
e-Learning CoursesKurs służy jako narzędzie pomocnicze do realizacji przedmiotu.
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Sławomir Jerzy Ambroziak dr hab. inż.
PeopleSławomir J. Ambroziak was born in Poland, in 1982. He received the M.Sc., Ph.D. and D.Sc. degrees in radio communication from Gdańsk University of Technology (Gdańsk Tech), Poland, in 2008, 2013, and 2020 respectively. Since 2008 he is with the Department of Radiocommunication Systems and Networks of the Gdańsk Tech: 2008-2013 as Research Assistant, 2013-2020 as Assistant Professor, and since 2020 as Associate Professor. He is...
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Jacek Stefański prof. dr hab. inż.
PeopleJJacek Stefański received M.Sc., Ph.D. and D.Sc. degrees in telecommunications engineering from Gdansk University of Technology (GUT), Poland, in 1993, 2000 and 2012, respectively. Awarded title of Professor by the President of Poland in 2020. Currently, he works as a professor at the Department of Radio Communication Systems and Networks (DRCSN) in GUT. From 2005 to 2009, he worked as an assistant professor in the National Institute...
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Measurement of Coherence Bandwidth in UHF Radio Channels for Narrowband Networks
PublicationThis paper presents results of investigation on the coherence bandwidth of narrowband radio channels in 430MHz band. The coherence bandwidth values were estimated froma power delay profile obtained by recording CDMA2000 forward channel signals during real-fieldmeasurements in various environments:mediumcity, flat terrain, and hilly terrain in northern Poland.The results of measurements are compared with characteristic parameters...
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Measurements of transmission properties of Acoustic Communication Channels
PublicationTough transmission properties of shallow water acoustic channels (SWAC) highly limit the use of underwater acoustic communication (UAC) systems. An adaptive matching of modulation and signaling schemes to instantaneous channel conditions is needed for reliabledata communications. This creates, however, unique challenges for designers when compared to radio transmission systems. When communication system elements are in move, the...
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferryboat Environment
PublicationIn the article an off-body narrowband and ultra-wide band channel model for body area networks in a ferryboat environment is described. Considering the limited number of publications there is a need to develop an off-body channel model, which will facilitate the design of radio links, both from the multimedia services provider and the security point of view, for body area networks in this atypical environment. A mobile heterogeneous...
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Measurement Stand and Methodology for Research of the Off-Body and Body-to-Body Radio Channels in WBANs with Different Diversity Schemes
PublicationThe concept of an experimental test bed for system loss and channel impulse response measurements for off-body and body-to-body radio channels in wireless body area networks (WBANs) is fully described. The possible measurement scenarios that may occur in investigation of off-body and body-to-body channels are classified and described in detail. Additionally, an evaluation is provided of the standard and expanded uncertainties of...
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The Analysis of Cross-Polarisation Discrimination for Body Area Networks in Cylindrical Metallic Environment
PublicationThe analysis of cross-polarisation discrimination for Body Area Networks in an untypical environment of cylindrical metallic room has been performed in the paper. This analysis was done based on the measurements carried out for dynamic narrowband off-body channels operating at the frequency of 2.45 GHz. The results have shown that there is a strong dependence of the depolarisation effect on the existence of direct component in...
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Position Estimation in Mixed Indoor-Outdoor Environment Using Signals of Opportunity and Deep Learning Approach
PublicationTo improve the user's localization estimation in indoor and outdoor environment a novel radiolocalization system using deep learning dedicated to work both in indoor and outdoor environment is proposed. It is based on the radio signatures using radio signals of opportunity from LTE an WiFi networks. The measurements of channel state estimators from LTE network and from WiFi network are taken by using the developed application....
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Application of Maximum-Length Sequences to impulse response measurement of hydroacoustic communications systems
PublicationThere 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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System Loss Model for Body Area Networks in Room Scenarios
PublicationThis paper presents an analysis of system loss in Body Area Networks for room scenarios, based on a wideband measurement campaign at 5.8 GHz. The measurements were performed with a fixed antenna transmitting vertically and horizontally polarised signals, while the user wears dualpolarised antennas. The average system losses in co- and crosspolarised channels are 41.4 and 42.6 dB for vertically polarised transmitted signals and...
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The Weibull model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The Weibull fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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A Novel Bitrate Adaptation Method for Heterogeneous Wireless Body Area Networks
PublicationIn the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation...
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A Novel Bitrate Adaptation Method for Heterogeneous Wireless Body Area Networks
PublicationIn the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation...
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Badanie i analiza efektywności alokacji strumieni danych w heterogenicznej sieci WBAN
PublicationW niniejszej dysertacji doktorskiej poddano dyskusji efektywność alokacji strumieni danych w heterogenicznej radiowej sieci WBAN (Wireless Body Area Networks). Biorąc pod uwagę dynamiczny rozwój nowoczesnych sieci radiokomunikacyjnych piątej generacji (5G), którego część stanowią radiowe sieci działające w obrębie ciała człowieka, bardzo ważnym aspektem są metody maksymalizujące wykorzystanie dostępnych zasobów czasowo –częstotliwościowych...
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Pomiar odpowiedzi impulsowej kanału radiowego na obszarze morskim i przybrzeżnym
PublicationW artykule zaprezentowano wyniki pomiarów odpowiedzi impulsowej kanału radiowego na obszarze morskim i przybrzeżnym. Pomiary przeprowadzono na częstotliwości 1457 MHz a sygnałem sondującym był sygnał o paśmie 10 MHz z modulacją BPSK i pseudoprzypadkową zawartością binarną. Odbierane sygnały były rejestrowane przez dwie stacje ruchome, zainstalowane w samolocie i na łodzi patrolowej. Podczas późniejszej obróbki danych zastosowano...
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Transmission Quality in MC-CDMA Radio Interface with Turbo Codes
PublicationMulti-Carrier Code Division Multiple Access techiques is a combination of two radio access techniques: Code Division Multiple Access (CDMA) and Orthogonal Frequency-called Division Multiplexing (OFDM) and has the advantages of both techniques. The paper presents the design of transmitter and receiver for MC-CDMA radio interface and the simulation results of the transmission quality in AWGN channel.
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LOS and NLOS identification in real indoor environment using deep learning approach
PublicationVisibility conditions between antennas, i.e. Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) can be crucial in the context of indoor localization, for which detecting the NLOS condition and further correcting constant position estimation errors or allocating resources can reduce the negative influence of multipath propagation on wireless communication and positioning. In this paper a deep learning (DL) model to classify LOS/NLOS...
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Vehicular Communication Environments
PublicationCommunication to and between road vehicles (cars, truck, buses, trains, etc.) are of growing interest. This is partly due to the attractive services that cooperative intelligent transport systems (C-ITSs) provides, mainly in the areas of traffic safety and traffic efficiency. An enabler for C-ITS is wireless vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, collectively referred to as vehicle-to-X (V2X)...
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Considerations of Adaptive Digital Communications in Underwater Acoustic Channel
PublicationDown-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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Performance analysis of data transmission in MC-CDMA radio interface with turbo codes
PublicationMulti-carrier code division multiple access (MC-CDMA) technique is a combination of two radio access techniques: CDMA and orthogonal frequency division multiplexing and has the advantages of both techniques. The paper presents the design of transmitter and receiver for MC-CDMA radio interface. It also presents encoders and decoders of turbo codes which were used in simulation of the MC-CDMA technique. Two turbo codes with 8-state...
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The Rayleigh model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The Rayleigh fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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Channel State Estimation in LTE-Based Heterogenous Networks Using Deep Learning
PublicationFollowing the continuous development of the information technology, the concept of dense urban networks has evolved as well. The powerful tools, like machine learning, break new ground in smart network and interface design. In this paper the concept of using deep learning for estimating the radio channel parameters of the LTE (Long Term Evolution) radio interface is presented. It was proved that the deep learning approach provides...
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The Transmission Protocol of Sensor Ad Hoc Networks
PublicationThis paper presents a secure protocol for a radio Ad Hoc sensor network. This network uses the TDMA multiple access method. The transmission rate on the radio channel is 57.6 kbps. The paper presents the construction of frames, types of packets and procedures for the authentication, assignment of time slots available to the node, releasing assigned slots and slots assignment conflict detection.
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Inhibition of T-type calcium channel disrupts Akt signaling and promotes apoptosis in glioblastoma cells.
PublicationGlioblastoma multiforme (GBM) are brain tumors that are exceptionally resitant to both radio- and chemotherapy regimens and novel approaches to treatment are needed. T-type calcium channels are one type of low voltage-gated channel (LVCC) involved in embryonic cell proliferation and differentiation; however they are often over-expressed in tumors, including GBM. In this study, we found that inhibition of T-type Ca channels in GBM...
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The secure transmission protocol of sensor Ad Hoc network
PublicationThe paper presents a secure protocol of radio Ad Hoc sensor network. This network operates based on TDMA multiple access method. Transmission rate on the radio channel is 57.6 kbps. The paper presents the construction of frames, types of packets and procedures for the authentication, assignment of time slots available to the node, releasing assigned slots and slots assignment conflict detection.
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Sensing Direction of Human Motion Using Single-Input-Single-Output (SISO) Channel Model and Neural Networks
PublicationObject detection Through-the-Walls enables localization and identification of hidden objects behind the walls. While numerous studies have exploited Channel State Information of Multiple Input Multiple Output (MIMO) WiFi and radar devices in association with Artificial Intelligence based algorithms (AI) to detect and localize objects behind walls, this study proposes a novel non-invasive Through-the-Walls human motion direction...
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The generalized Suzuki model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The generalized Suzuki fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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The lognormal model of the multipath fading channel
Open Research DataThe dataset contains the results of simulations that are part of the research on modelling the multipath fading in the communication channel. The lognormal fading envelope is generated using the Monte-Carlo simulation (MCS) in the LabVIEW programming environment.
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An Off-Body Narrowband and Ultra-Wide Band Channel Model for Body Area Networks in a Ferry Environment
PublicationIn the article an off-body narrowband and ultra-wide band channel model for Body Area Networks in a ferry environment is described. A mobile, heterogeneous measurement stand, that consists of three types of devices: miniaturized mobile nodes, stationary reference nodes and a data acquisition server was developed. A detailed analysis of both radio channels parameters in untypical indoor environment was carried out. An analysis of...
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Application of OFDM technique to underwater acoustic data transmission
PublicationPerformances of underwater acoustic communication (UAC) digital systems are strongly related to specific transmission properties of the underwater channel. Depending on the characteristics of the channel, an architecture and modulation techniques are usually implemented that are known as reliable solutions for data transmission in difficult radio channels. The OFDM technique seems to be the most promising nowadays. The parameters...
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Underwater Acoustic Communications in Time-Varying Dispersive Channels
PublicationUnderwater 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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User Orientation Detection in Relation to Antenna Geometry in Ultra-Wideband Wireless Body Area Networks Using Deep Learning
PublicationIn this paper, the issue of detecting a user’s position in relation to the antenna geometry in ultra-wideband (UWB) off-body wireless body area network (WBAN) communication using deep learning methods is presented. To measure the impulse response of the channel, a measurement stand consisting of EVB1000 devices and DW1000 radio modules was developed and indoor static measurement scenarios were performed. It was proven that for...
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RADIATION MEASUREMENTS
Journals -
LSTM-based method for LOS/NLOS identification in an indoor environment
PublicationDue to the multipath propagation, harsh indoor environment significantly impacts transmitted signals which may adversely affect the quality of the radiocommunication services, with focus on the real-time ones. This negative effect may be significantly reduced (e.g. resources management and allocation) or compensated (e.g. correction of position estimation in radiolocalisation) by the LOS/NLOS identification algorithm. This paper...
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Device for spoofing in global positioning system
PublicationThis article describes the device which may be used to generate false GPS signals and emit them into radio communication channel. Such attack is called GPS spoofing. Each GPS receiver which remains in the range of a spoofing device (called spoofer) indicates time and position coordinates which are predetermined by the spoofer’s operator. Spoofing may be used e.g. in order to disable the terrorist group from obtaining correct navigation...
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Nowy wewnątrzbudynkowy algorytm wyznaczania położenia obiektów
PublicationW referacie zaprezentowano nowy wewnątrzbudynkowy algorytm wyznaczania położenia obiektów WAP. W algorytmie tym uwzględnia się właściwości środowiska propagacyjnego, dzięki czemu dokładność estymat położenia obiektów wyznaczonych algorytmem WAP jest większa niż wyznaczonych znanymi algorytmami Chana oraz Foy’a. W referacie przedstawiono wyniki analizy porównawczej tych trzech algorytmów z użyciem rzeczywistych pomiarów odległości...
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Lokalizacja osób w środowisku promu pasażerskiego z wykorzystaniem ultra szerokopasmowego interfejsu radiowego
PublicationW niniejszym artykule przedstawiono badania efektywności lokalizowania poruszających się osób w środowisku promu pasażerskiego stosując pomiar czasu propagacji ultraszerokopasmowego sygnału radiowego UWB (Ultra-Wide Band) pomiędzy węzłami odniesienia i terminalem ruchomym. Opisano zbudowane stanowisko badawcze oraz uzyskane wyniki pomiarów przeprowadzonych w warunkach rzeczywistych.
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Fluid Mechanics, L/L/E, DaPE, sem. 04, summer 21/22 (PG_00050282)
e-Learning CoursesLECTURES Introduction and basic definitions. Properties of fluids. Models of fluids. Fluids in equilibrium. Determination of hydrostatic forces. Archimedes" law. Methods of fluid flow description. General motion of fluid. Deformation of fluid element. Vortex motion of fluid. Principles of conservation of mass, momentum and energy. Balance of entropy. Navier-Stokes equation. Bernoulli equation. Similarity of flow phenomena. Potential...
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Model neuronowy jako alternatywa dla numerycznego modelu okołodźwiękowego przepływu pary przez palisadę turbinową.
PublicationWystępowanie skośnej fali uderzeniowej w przepływie pary przez palisadę turbinową stanowi zagrożenie dla bezpiecznej pracy turbiny oraz dla jej elementów konstrukcyjnych. Detekcja oraz lokalizacja fali uderzeniowej, a także rozpoznanie przyczyny jej powstawania, nie są możliwe do osiągnięcia na drodze pomiarowej. Analizę zjawisk zachodzących wewnątrz kanału przepływowego umożliwiają natomiast modele numeryczne oraz neuronowe. Zaletą...
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Badania i analiza uwarunkowań propagacyjnych w środowisku uprzemysłowionym
PublicationGłówne osiągnięcia rozprawy: - wykonanie – zgodnie z wymaganiami normatywnymi zawartymi w zaleceniach ITU-R – nowatorskich badań tłumienia sygnału radiowego na terenie Głębokowodnego Terminalu Kontenerowego (ang. Deepwater Container Terminal - DCT) w Gdańsku i zebranie obszernego materiału pomiarowego, liczącego blisko 290 tysięcy przypadków propagacyjnych, - przeprowadzenie statystycznych badań przydatności wybranych znanych modeli...
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Geology and hydrology 2023
e-Learning CoursesW części "geology" studenci zapoznają się z procesami wewnętrznymi i zewnętrznymi, zwłaszcza prowadzącymi do rozpoznawania skał i minerałów. Uczą się metod rozpoznawania i sposobu opisu skał i minerałów. Zapoznają się z warunkami występowania wód podziemnych, uczą się interpretacji danych geologicznych i hydrogeologicznych. W części "hydrology" studenci zapoznają się z nastepującą tematyką: formowanie się opadu, pomiar opadu,...
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Geology and hydrology
e-Learning CoursesW części "hydrology" studenci zapoznają się znastepującą tematyką: formowanie się opadu, pomiar opadu, spływ powierzchniowy, nadwyżka opadu, hydrogram jednostkowy, transformacja fali wezbraniowej, przepływ w kanale otwartym, podstawowe informacje o budowlach hydrotechnicznych. W częśi "geology" studenci zapoznają się z procesami wewnętrznymi i zewnętrznymi, zwłaszcza prowadzącymi do rozpoznawania skał i minerałów. Uczą się metod...
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Wideband Radio Direction Finder Implemented in Software Defined Radio Technology
PublicationIn the paper a wideband radio direction finder (RDF) implemented in software defined radio (SDR) technology and the results of hardware layer research, including developed antenna switching unit (ASU), are presented. The results of tests of the devices, which are the part of the software defined radio platform (SDRP), and antenna switching unit, confirmed the possibility of using selected components in the final solution.
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Radio Link Measurement Methodology for Location Service Applications
PublicationThe aim of this paper is the methodology of measurements executed in a radio link for the realization of radiolocation services in radiocommunication networks, particularly in cellular networks. The main results of the measurements obtained in the physical layer of the universal mobile telecommunications system (UMTS) are introduced. A new method for the utilization of the multipath propagation phenomenon to improve the estimation...
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Measurements and Measurements Systems [2023/24]
e-Learning Courses -
Velocity measurement using the fdoa method in ground-based radio navigation system
PublicationVelocity is one of the main navigation parameters of the moving objects. However some systems of position estimation using radio wave measurements cannot provide velocity data due to limitation of their performance. In this paper a velocity measurement method for DS-CDMA radio navigation system is proposed, which doesn’t require full synchronization of reference stations carrier frequencies. The article presents basics of FDOA...
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Monitoring wizyjny w systemach zabezpieczenia transportu wodnego. Koncepcja implementacyjna
PublicationW artykule autorzy przedstawiają koncepcję zastosowania własnych badań nad pomiarem prędkości przepływu cieczy do zastosowań praktycznych w pomiarach przepływu wody w kanałach otwartych i rzekach. Jako narzędzie pomiarowe wykorzystują zestaw aparatów synchronicznych, które rejestrują indykatory przepływu znajdujące się na powierzchni analizowanej cieczy. Aparat matematyczny przedstawiony w rozwiązaniu sprowadza się do stosowania...
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Measuring research on radio wave propagation
PublicationTelecommunication connections are increasingly based on the wireless links, both fixed and mobile, carried out under different radio systems. This kind of solution has many advantages. However, the propagation medium is a factor that causes many difficulties in designing wireless networks, because of large diversity of propagation environments. Transmission loss in each environment is determined by many variables phenomena and...
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Impact of radio wave polarisation on off-body communications in indoor environments
PublicationThis 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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Estimation of transmission quality in cellular systems based on indicators measured by the radio module
PublicationThe article presents a measurement stand for testing transmission quality in cellular systems such as LTE, NB-IoT, UMTS and GSM. The results of BLER and throughput measurements for various propagation conditions as well as results of quality indicators appropriate for mentioned technologies measured by commercial radio module are presented. Those measurements were utilized to analyze the possibility of estimating the transmission...
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Trunked Radio Solutions for Special Application
PublicationIn the paper modern concepts of radio communication trunking-dispatch systems for special applications are presented. Basic standards of TETRA, DMR, and cdma2000 are mentioned. The aim of the paper is to present innovative trunking solutions based on the LTE system working both in FDD and TDD mode. The architecture of LTE trunked radio is shown as well as new services possible to implementation are described. The way of TETRA and...
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The Boltzmann sequence-structure channel
PublicationWe rigorously study a channel that maps binary sequences to self-avoiding walks in the two-dimensional grid, inspired by a model of protein statistics. This channel, which we also call the Boltzmann sequence-structure channel, is characterized by a Boltzmann/Gibbs distribution with a free parameter corresponding to temperature. In our previous work, we verified experimentally that the channel capacity has a phase transition for...
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Survey of Radio Navigation Systems
PublicationAt present, there is a growing demand for radio navigation systems, ranging from pedestrian navigation to consumer behavior analysis. These systems have been successfully used in many applications and have become very popular in recent years. In this paper we present a review of selected wireless positioning solutions operating in both indoor and outdoor environments. We describe different positioning techniques, methods, systems,...
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Measurement and Analysis of the Radio Wave Polarisation in Off-Body Communications in Indoor Environment
PublicationThe 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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Radio Physics and Radio Astronomy
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Wideband Off-Body Channel Characteristics with Dynamic User
PublicationThis paper presents the preliminary results of a dynamic off-body channel characterisation study, based on wideband measurements at 5.8 GHz in an indoor environment. The Channel Impulse Response (CIR) was measured for a scenario with the user approaching and departing from the off-body antenna. A CIR deconvolution procedure was performed jointly in two polarisations, and the received signal power, Cross-Polarisation Discrimination...
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Limitations of WSSUS modeling of stationary underwater acoustic communication channel
PublicationPerformances of underwater acoustic communication (UAC) systems are strongly related to specific propagation conditions of the underwater channel. Due to their large variability, there is a need for adaptive matching of the UAC systems signaling to the transmission properties of the channel. This requires a knowledge of instantaneous channel characteristics, in terms of the specific parameters of stochastic models. The wide-sense...
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Radio programowalne - nowoczesna platforma dydaktyczna
PublicationPrzedstawiono technologię radia programowalnego jako nowoczesną platformę dydaktyczną. Zaproponowane podejście pozwala na efektywniejsze planowanie stanowisk laboratoryjnych. Umożliwia skrócenie czasu realizacji etapów związanych z projektowaniem, symulacją i testowaniem działania łącza radiowego. Pozwala również na elastyczną zmianę stanowisk laboratoryjnych zgodnie z dynamicznym rozwojem współczesnych systemów radiokomunikacyjnych.
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Person Tracking in a Ferry Environment Using Ultra-Wide Band Radio Interface
PublicationThis article presents research and analysis of effectiveness of tracking moving people in an environment of passenger ferry, using measurements of propagation time of ultra-wide band radio signal (UWB - Ultra-Wide Band). Constructed measurement stand and results of measurements carried out in a real propagation conditions were shortly discussed.
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Radio Communication Antennas and MIMO Techniques (2023/24)
e-Learning CoursesCourse assigned to the following subject: - Radio Communication Antennas and MIMO Techniques (profile Radio Communication Systems and Networks [EN])
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Characteristics of the polarised off-body channel in indoor environments
PublicationThis paper addresses the depolarisation effect in off-body body area networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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Phase Transition in a Sequence-Structure Channel
PublicationWe study an interesting channel which maps binary sequences to self-avoiding walks in the two-dimensional grid, inspired by a model of protein folding from statistical physics. The channel is characterized by a Boltzmann/Gibbs distribution with a free parameter corresponding to temperature. We estimate the conditional entropy between the input sequence and the output fold, giving an upper bound which exhibits an unusual phase transition...
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Design of radio communication systems for unmanned transport applications
PublicationIn the paper the principle of OFDMA-based radio communication systems design for unmanned transport applications is presented. The concept of system radio interface is analysed and its basic parameters proposal are considered. In the last part of the paper some air interface characteristics useful for optimization of throughput and system capacity are considered.
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Assessment of the Accuracy of a Virtual Multi-Channel Temperature Measuring Instrument
PublicationThe multi-channel temperature measurement system developed works with NTC thermistors. The article presents the results of theoretical and empirical evaluation of accuracy obtained in measurement channels. The basis for the theoretical assessment is the mathematical model for each of the measurement channels and the characteristics of the system elements included in the circuits of the measurement channel. Two different methods were...
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Characteristics of the Polarised Off-Body Channel in Indoor Environments
PublicationThis paper addresses the depolarisation effect in off-body Body Area Networks channels, based on measurements performed at 2.45 GHz in an indoor environment. Seven different scenarios, involving both static and dynamic users, were considered, taking a statistical perspective. The analysis of the cross-polarisation discrimination is performed, as well as the analysis of path loss in co- and cross-polarised channels. Results show...
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A simplified channel estimation procedure for NB-IoT downlink
PublicationThis paper presents a low-complexity channel estimation procedure which is suitable for use in energy-efficient NB-IoT user equipment devices. The procedure is based on the well-established least squares scheme, followed by linear interpolation in the time domain and averaging in the frequency domain. The quality of channel estimation vs. signal-to-noise ratio is evaluated for two channel models and compared with the performance...
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New Indoor Positioning Algorithm for Distance Measurements
PublicationIn the paper a new indoor positioning algorithm is presented. This algorithm takes into account selected features of radio wave propagation in indoor environment. This results in improvement in accuracy of calculated position estimates. A comparative analysis of this new algorithm with Chan and Foy algorithms was made and described in the paper. This comparative analysis was made with utilization of real radio distance measurements.
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A simple test for quantum channel capacity
PublicationBased on state and channel isomorphism we point out that semidefiniteprogramming can be used as a quick test for nonzero one-way quantum channelcapacity. This can be achieved by searching for symmetric extensions of statesisomorphic to a given quantum channel. With this method we provide examplesof quantum channels that can lead to high entanglement transmission but stillhave zero one-way capacity, in particular, regions of symmetric...
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Multi-Channel Virtual Instrument for Measuring Temperature—A Case Study
PublicationThe article presents the hardware and software configuration of the developed multi-channel temperature measurement system as well as calibration procedures and measurement results verifying the properties of measurement channels. The system has been developed and dedicated primarily for measuring the temperature distribution in a laboratory model simulating underground power lines. With the adopted configuration of the analog...
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A Simplistic Downlink Channel Estimation Method for NB-IoT
PublicationThis paper presents a downlink channel estimation method intended for a Narrowband Internet of Things (NB-IoT) access link. Due to its low computational complexity, this method is well suited for energy-efficient IoT devices, still providing acceptable reception quality in terms of signal-to-noise (SNR) performance. This paper describes the physical layer of NB-IoT within the scope of channel estimation, and also reviews existing...
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On the Characteristic Graph of a Discrete Symmetric Channel
PublicationWe present some characterizations of characteristic graphs of row and/or column symmetric channels. We also give a polynomial-time algorithm that decides whether there exists a discrete symmetric channel whose characteristic graph is equal to a given input graph. In addition, we show several applications of our results.
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Application of Diversity Combining with RLS Adaptive Filtering in Data Transmission in a Hydroacoustic Channel
PublicationWhen transmitting data in a hydroacoustic channel under difficult propagation conditions, one of the problems is intersymbol interference (ISI) caused mainly by the effect of multipath propagation. This phenomenon leads to a decrease in transmission parameters, and sometimes completely prevents it. Therefore, we have made an attempt to use diversity combining with Recursive Least Squares (RLS) adaptive filtering to improve the...
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Reduction of the Multipath Propagation Effect in a Hydroacoustic Channel Using Filtration in Cepstrum
PublicationDuring data transmission in a hydroacoustic channel, one of the problems is the multipath propagation effect, which leads to a decrease in the transmission parameters and sometimes completely prevents it. Therefore, we have attempted to develop a method, which is based on a recorded hydroacoustic signal, that allows us to recreate the original (generated) signal by eliminating the multipath effect. In our method, we use cepstral...
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Local buckling of composite channel columns
PublicationThe investigation concerns local buckling of compressed flanges of axially compressed composite channel columns. Cooperation of the member flange and web is taken into account here. The buckling mode of the member flange is defined by rotation angle a flange about the line of its connection with the web. The channel column under investigation is made of unidirectional fibre-reinforced laminate. Two approaches to member orthotropic...
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Signals of the 5G Standalone Radio Interface
Open Research DataThe research work conducted within the scope of NATO-STO (North Atlantic Treaty Organization – Science and Technology Organization) IST-187 group assumed investigation of the 5G gNodeB performance. The downlink (DL) signals of the FDD (Frequency Division Duplex) 5G-Standalone station were registered in isolated and controlled laboratory conditions....
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Radio Journal
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RADIO SCIENCE
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Estimation of Coherence Bandwidth for Underwater Acoustic Communication Channel
PublicationA shallow underwater acoustic communication channel is characterized by strong multipath propagation. The signal reaching the receiver consists of a direct waveform and a number of its delayed and suppressed replica. A significant time dispersion of the transmitted signal and selective fading of its spectrum are observed. Coherence bandwidth defines maximal bandwidth, wherein the channel amplitude characteristic remains constant...
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Radio Simulcasting at a Glance: a New Look at Broadcasting and Streaming Services
PublicationRadio is by far one of the most popular and accessible medium. With its availability it attracts listeners all around the world. There are numerous ways of delivering content to consumers. The present situation is characterized by the convergence of acoustics, computer science and telecommunications. This paper reviews the current status of radio broadcasting and streaming services. It describes a subjective study concerning different...
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Radio Reception Signal
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Towards 5G — Cloud-based Radio Access Networks
PublicationIn the paper a general concept of the 5G network architecture is presented as well as system requirements having impact on innovative solutions in the 5G network are highlighted. A major part of the paper is both presentation and discussion of the problem of Cloud Radio Access Network introduction for public networks in which the cell and resource virtualisation will be implemented. On the other hand, the problem of resource virtualization...
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Devices and Methods of Measurements
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Steady magnetohydrodynamic flow in a diverging channel with suction or blowing
PublicationAn analysis is made of steady two-dimensional divergent flow of an electrically conducting incompressible viscous fluid in a channel formed by two non-parallel walls, the flow being caused by a source of fluid volume at the intersection of the walls. The fluid is permeated by a magnetic field produced by an electric current along the line of intersection of the channel walls. The walls are porous and subjected to either suction...