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Search results for: ADOA
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TDOA versus ATDOA for wide area multilateration system
PublicationThis paper outlines a new method of a location service (LCS) in the asynchronous wireless networks (AWNs) where the nodes (base stations) operate asynchronously in relation to one another. This method, called asynchronous time difference of arrival (ATDOA), enables the calculation of the position of the mobile object (MO) through the measurements taken by a set of non-synchronized fixed nodes and is based on the measurement of...
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Analiza porównawcza metody TDOA i ATDOA w systemie WAM
PublicationW artykule przedstawiono nową metodę estymacji położenia obiektów w radiowych sieciach sensorowych, w których węzły pracują asynchronicznie względem siebie. Opisano zasadę działania metody, zaprezentowano przykładowe zastosowanie tej metody w przestrzeni 3D wraz z przyjętym modelem symulacyjnym i wynikami badań. Istotną część artykułu stanowi analiza porównawcza efektywności pracy zaproponowanej metody z metodą synchroniczną dla...
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ASYNCHRONICZNA METODA TDOA
PublicationPrzedstawiono nową metodę lokalizowania terminali ruchomych MT (Mobile Terminal) w sieciach radiowych, w których stacje bazowe BS (Base Station) pracują asynchronicznie względem siebie. Metoda ta, nazwana ATDOA (Asynchronous Time Difference of Arrival), umożliwia estymację położenia MT na podstawie pomiarów różnicy czasów propagacji sygnałów radiowych pomiędzy terminalem ruchomym będącym w ruchu, a pojedynczą stacją bazową w różnych...
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Bad geometry effect in TDOA systems
PublicationW artykule przedstawiono wpływ tzw. złej geometrii (ZG) rozmieszczenia stacji bazowych na dokładność estymacji położenia terminala w sieciach komórkowych, wykorzystujących metodę TDOA. Zdefiniowano podstawowe parametry opisujące złą geometrię oraz przedstawiono praktyczne wskazówki jak poprawić dokładnośc estymacji położenia terminala ruchomego w przypadku wystąpienia ZG.
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Asynchronous time difference of arrival (ATDOA) method
PublicationA new method for a location service in the asynchronous wireless sensor networks is outlined. This method, which is called asynchronous time difference of arrival (ATDOA), enables calculation of the position of a mobile node without knowledge of relative time differences (RTDs) between measuring sensors. The ATDOA method is based on the measurement of time difference of arrival between the node and the same sensor at the discrete...
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Organometallic block copolymers as catalyst precursors for templated carbon nanotube growth.
PublicationArtykuł przedstawia zastosowanie organometalicznych kopolimerów blokowych jako prekursorów katalizatorów dla syntezy nanorurek węglowych. Zjawisko mikroseparacji fazowej kopolimerów blokowych zostało wykorzystane dla przygotowania matrycy aktywnych katalitycznie domen o rozmiarach ~20 nm. Domeny zawierające poli(ferrocenylosilan) (PFS) po utlenienu w plazmie tlenowej oraz redukcji z Fe(III) do Fe(II) oraz Fe(0) z powodzeniem katalizują...
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TDOA Navigation Using CDMA2000 Signals – Experimental Results
PublicationThis paper presents results of an experiments on the possibility to estimate position of a CDMA2000 receiver on the basis of TDOA measurements. The hardware and software structure of a navigation receiver used during investigation is briefly described with focus on drawbacks and limitations. The main part of this paper contains basic information about CDMA2000 network in northern Poland, which signals were recorded during tests...
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Extension of selected ADFA construction algorithms to the case of cyclic automata.
PublicationW niedawnym artykule Rafael Carrasco i Mikel Forcada przedstawiają przyrostowy algorytm dodawania słów do minimalnego, acyklicznego automatu skończonego. Ten algorytm jest uogólnieniem przyrostowego algorytmu tworzenia acyklicznych deterministycznych automatów skończonych (ADFAs). Przedstawiamy podobne uogólnienia dwóch innych algorytmów tworzenia ADFAs. Chociaż te ougólnienia zostały już opublikowane w maju i czerwcu 2004 r.,...
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Capon-like DoA estimator for rotating arrays
PublicationWe propose a nonparametric superresolution DoA estimator that is suitable for use with rotating arrays. The proposed method can be regarded as an extension of the Capon approach. We investigate its properties using computer simulations and present results obtained by processing of real world data.
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Poprawa rozdzielczości pomiarów TDOA w radionawigacyjnym odbiorniku DS-CDMA
PublicationReferat przedstawia propozycję poprawy rozdzielczości pomiaru różnic czasów nadejścia sygnałów (TDOA) w odbiorniku DS-CDMA do celów radiolokalizacyjnych i radionawigacyjnych przy użyciu pętli śledzenia fazy ciągu rozpraszającego wykorzystującej filtry ułamkowoopóźniające. Opisana jest budowa i funkcjonowanie proponowanego rozwiązania wraz z wynikami badań laboratoryjnych.
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Nieautoryzowany dostęp do usługi lokalizacyjnej w fazowym systemie TDOA
PublicationReferat zawiera opis sposobu obliczania pozycji stacji bazowych hiperbolicznego systemu nawigacyjnego na podstawie pomiarów różnicy czasów propagacji sygnałów w kilku znanych punktach pomiarowych. Przedstawiono także sposób usuwania niejednoznaczności wyników w systemie fazolokacyjnym oraz podano przykłady obliczeniowe z obszaru Zatoki Gdańskiej.
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Filtracja danych TDOA w filtrze UKF w systemie multilateracyjnym
PublicationW artykule przedstawiono implementację metody filtracji danych pomiarowych w systemie MLAT(Multilateration), która ma na celu zwiększenie dokładności estymacji położenia poruszającego się statku powietrznego poprzez kompensację błędów pomiarowych. Opisano sposób implementacji algorytmu bezśladowego filtru Kalmana dla danych pomiarowych TDOA (Time Difference of Arrival), a następnie na podstawie zarejestrowanych rzeczywistych tras...
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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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Badawczo-rozwojowe laboratorium sieci optycznych wykorzystujące sprzęt ADVA Optical Networking
PublicationPrzedstawiono uwarunkowania i kierunki zmian w sieciach optycznych, a następnie wskazano na potrzebę posiadania laboratorium, w którym możliwe byłoby prowadzenie prac badawczo-rozwojowych oraz kształcenie. Przedstawiono koncepcję takiej sieci opartej na sprzęcie ADVA Optical Networking zrealizowaną w Katedrze Sieci Teleinformacyjnych Wydziału ETI PG. Opisano możliwości sprzętowo-funkcjonalne tego laboratorium oraz prowadzone prace...
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On Radar DoA Estimation and Tilted Rotating Electronically Scanned Arrays
PublicationWe consider DoA estimation in a monopulse radar system employing a tilted rotating array. We investigate the case of nonzero steering angles, in which case the mapping between the target’s azimuth and elevation in the global coordinate system and their counterparts in the array local coordinate system becomes increasingly nonlinear and coupled. Since estimating the azimuth using coherently integrated signals might be difficult because...
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ESPAR Antenna-Based WSN Node With DoA Estimation Capability
PublicationIn this paper, we present a low-cost energy-efficient electronically steerable parasitic array radiator (ESPAR) antenna-based wireless sensor network (WSN) node designed for IEEE 802.15.4 standard that is capable of performing direction of arrival (DoA) estimation in real-life outdoor environments. To this end, we propose the WSN node architecture, design and realization that utilizes NXP JN5168 radio frequency (RF) wireless transceiver...
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Analiza wpływu konfiguracji stacji pomiarowych na dokładność pozycjonowania w metodzie TDOA
PublicationW artykule dokonano analizy wpływu konfiguracji stacji pomiarowych na dokładność estymacji położenia geograficznego terminala w systemach wykorzystujących metodę TDOA (Time Difference of Arrival). W pierwszej części przedstawiono model symulacyjny wykorzystany do badań. Zaprezentowano również model statystyczny, który wykorzystano do wyznaczenia parametru geometrycznego rozmycia pozycji GDOP (Geometric Dilution of Precision) w...
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Calibration of acoustic vector sensor based on MEMS microphones for DOA estimation
PublicationA procedure of calibration of a custom 3D acoustic vector sensor (AVS) for the purpose of direction of arrival (DoA) estimation, is presented and validated in the paper. AVS devices working on a p-p principle may be constructed from standard pressure sensors and a signal processing system. However, in order to ensure accurate DoA estimation, each sensor needs to be calibrated. The proposed algorithm divides the calibration process...
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Using the Fingerprinting Method to Customize RTLS Based on the AoA Ranging Technique
PublicationReal-time Locating Systems (RTLSs) have the ability to precisely locate the position of things and people in real time. They are needed for security and emergency applications, but also for healthcare and home care appliances. The research aims for developing an analytical method to customize RTLSs, in order to improve localization performance in terms of precision. The proposed method is based on Angle of Arrival (AoA), a ranging...
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On DoA estimation for rotating arrays using stochastic maximum likelihood approach
PublicationThe flexibility needed to construct DoA estimators that can be used with rotating arrays subject to rapid variations of the signal frequency is offered by the stochastic maximum likelihood approach. Using a combination of analytic methods and Monte Carlo simulations, we show that for low and moderate source correlations the stochastic maximum likelihood estimator that assumes noncorrelated sources has accuracy comparable to the...
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DoA Estimation Using Reconfigurable Antennas in Millimiter-Wave Frequency 5G Systems
PublicationTo achieve low latency and high throughputs, future 5G systems will have to utilize complex antenna systems able to provide beamforming and direction-of-arrival (DoA) estimation capabilities. Most of the concepts available in the literature rely on analog or digital beamforming, which is well developed and can be used both at a base station and in a user terminal. However, in applications, in which...
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A novel calibration method for RSS-based DoA estimation using ESPAR antennas
PublicationIn this paper, we introduce a new calibration method that can successfully be used in direction of arrival (DoA) estimation using electronically steerable parasitic array radiator (ESPAR) antennas and employing power-pattern cross-correlation (PPCC) algorithm, which relies on received signal strength (RSS) values recorded at the antenna output port. Instead of the commonly used two-step approach, during which ESPAR antenna calibration...
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RSS-based DoA Estimation Using ESPAR Antennas and Interpolated Radiation Patterns
PublicationIn this letter, it is shown how an algorithm, which employs received signal strength (RSS) values in order to estimate direction-of-arrival (DoA) of impinging signals in wireless sensor network (WSN) nodes equipped with electronically steerable parasitic array radiator (ESPAR) antennas, can easily be improved by applying an interpolation algorithm to radiation patterns recorded in the calibration phase of the DoA estimation process....
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RSS-Based DoA Estimation for ESPAR Antennas Using Support Vector Machine
PublicationIn this letter, it is shown how direction-of-arrival (DoA) estimation for electronically steerable parasitic array radiator (ESPAR) antennas, which are designed to be integrated within wireless sensor network nodes, can be improved by applying support vector classification approach to received signal strength (RSS) values recorded at an antenna's output port. The proposed method relies on ESPAR antenna's radiation patterns measured...
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Low-Profile ESPAR Antenna for RSS-Based DoA Estimation in IoT Applications
PublicationIn this paper, we have introduced a low-profile electronically steerable parasitic array radiator (ESPAR) antenna that can successfully be used to estimate the direction-of-arrival (DoA) of incoming signals in wireless sensor network (WSN) applications, in which the height of the complete antenna has to be low. The proposed antenna is over three times lower than high-profile ESPAR antenna designs currently available in the literature...
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Influence of ESPAR Antenna Radiation Patterns Shape on PPCC-Based DoA Estimation Accuracy
PublicationIn the article, we show the influence of three different electronically steerable parasitic array radiator (ESPAR) antenna radiation patterns on the overall direction of arrival (DoA) estimation accuracy when power-pattern cross-correlation (PPCC) algorithm, relying on received signal strength (RSS) values, is used for the estimation. The ESPAR antenna designs were obtained for three optimization...
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RSS-Based DoA Estimation Using ESPAR Antenna Radiation Patterns Spline Interpolation
PublicationIn this paper, it is shown how power pattern crosscorrelation (PPCC) algorithm, which relies on received signal strength (RSS) values recorded at electronically steerable parasitic array radiator (ESPAR) antenna output port, used for direction-of-arrival (DoA) estimation, can easily be improved by applying spline interpolation to radiation patterns recorded in the calibration phase of the DoA estimation process. The proposed method...
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Influence of ESPAR antenna radiation patterns shape on PPCC-based DoA estimation accuracy
PublicationIn the article, we show the influence of three different electronically steerable parasitic array radiator (ESPAR) antenna radiation patterns on the overall direction of arrival (DoA) estimation accuracy when power-pattern cross-correlation (PPCC) algorithm, relying on received signal strength (RSS) values, is used for the estimation. The ESPAR antenna designs were obtained for three optimization goals, which resulted in different...
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Customization of UWB 3D-RTLS Based on the New Uncertainty Model of the AoA Ranging Technique
PublicationThe increased potential and effectiveness of Real-time Locating Systems (RTLSs) substantially influence their application spectrum. They are widely used, inter alia, in the industrial sector, healthcare, home care, and in logistic and security applications. The research aims to develop an analytical method to customize UWB-based RTLS, in order to improve their localization performance in terms of accuracy and precision. The analytical...
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RSS-Based DoA Estimation Using ESPAR Antenna for V2X Applications in 802.11p Frequency Band
PublicationIn this paper, we have proposed direction-of arrival (DoA) estimation of incoming signals for V2X applications in 802. 11p frequency band, based on recording of received signal strength (RSS) at electronically steerable parasitic array radiator (ESPAR) antenna's output port. The motivation of the work was to prove that ESPAR antenna used to increase connectivity and security in V2X communication can...
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Efficient RSS-Based DoA Estimation for ESPAR Antennas Using Multiplane SDR Calibration Approach
PublicationIn this paper, we have introduced a new method to improve overall efficiency of direction-of-arrival (DoA) estimation scheme relying on received signal strength (RSS) values measured at the output port of electronically steerable parasitic array radiator (ESPAR) antenna. The proposed approach uses software-defined radio (SDR) setup and power pattern cross-correlation (PPCC) estimator involving multiple calibration planes. By placing...
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RSS-Based DoA Estimation Using ESPAR Antenna for V2X Applications in 802.11p Frequency Band
PublicationIn this paper, we have proposed direction-of arrival (DoA) estimation of incoming signals for V2X applications in 802. 11p frequency band, based on recording of received signal strength (RSS) at electronically steerable parasitic array radiator (ESPAR) antenna's output port. The motivation of the work was to prove that ESPAR antenna used to increase connectivity and security in V2X communication can be also used for DoA estimation....
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Improved RSS-Based DoA Estimation Accuracy in Low-Profile ESPAR Antenna Using SVM Approach
PublicationIn this paper, we have shown how the overall performance of direction-of-arrival (DoA) estimation using lowprofile electronically steerable parasitic array radiator (ESPAR) antenna, which has been proposed for Internet of Things (IoT) applications, can significantly be improved when support vector machine (SVM) approach is applied. Because the SVM-based DoA estimation method used herein relies solely...
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Improved RSS-Based DoA Estimation Accuracy in Low-Profile ESPAR Antenna Using SVM Approach
PublicationIn this paper, we have shown how the overall performance of direction-of-arrival (DoA) estimation using lowprofile electronically steerable parasitic array radiator (ESPAR) antenna, which has been proposed for Internet of Things (IoT) applications, can significantly be improved when support vector machine (SVM) approach is applied. Because the SVM-based DoA estimation method used herein relies solely on received signal strength...
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RSS-Based DoA Estimation in 802.11p Frequency Band Using ESPAR Antenna and PPCC-MCP Method
PublicationIn this paper, the concept of direction of arrival (DoA) estimation using electronically steerable parasitic array radiator (ESPAR) antenna designed to operate in IEEE 802.11p vehicular communication standard has been investigated with respect to different possible elevation angles of a radio frequency (RF) signal impinging the antenna. To this end, two different possible sets of the 3D antenna radiation patterns have been used...
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Accurate PPCC-Based DoA Estimation Using Multiple Calibration Planes for WSN Nodes Equipped with ESPAR Antennas
PublicationIn this paper, we have introduced a new direction-of-arrival (DoA) estimation method, which relies on received signal strength (RSS) values measured at the output port of electronically steerable parasitic array radiator (ESPAR) antenna and uses the power pattern cross-correlation (PPCC) estimator. In the method, we have successfully incorporated measurements of ESPAR antenna's radiation patterns performed at multiple calibration...
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Direction-of-Arrival Estimation Using an ESPAR Antenna with Simplified Beam Steering
PublicationIn this paper, it has been shown, how electronically steerable parasitic array radiator (ESPAR) antenna, in which beam steering is done in a simple way, can be used for directionof- arrival (DoA) estimation of an unknown signal impinging the antenna. The concept is based on an ESPAR antenna having twelve parasitic elements, in which beam switching is realized by RF switches providing required loads to its parasitic elements. Numerical...
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Detection and Direction-of-Arrival Estimation of Weak Spread Spectrum Signals Received with Antenna Array
PublicationThis paper presents a method for the joint detection and direction of arrival (DOA) estimation of low probability of detection (LPD) signals. The proposed approach is based on using the antenna array to receive spread-spectrum signals hidden below the noise floor. Array processing exploits the spatial correlation between phase-delayed copies of the signal and allows us to evaluate the parameter used to make the decision about the...
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Alternative and new plants
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Low Cost Method for Location Service in the WCDMA System
PublicationA new and low cost method for a location service (LCS) in the Wideband Code Division Multiple Access (WCDMA) system is outlined. This method, which is called TDOA + RTT, enables calculation of the geographical position of a mobile station (MS) without knowledge of relative time differences (RTDs) between base stations (BSs). The TDOA+RTT method is based on the measurement of round trip times (RTTs) between the MS and the serving...
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Simple 2-D Direction-of-Arrival Estimation Using an ESPAR Antenna
PublicationIn this letter, it has been shown how an electronically steerable parasitic array radiator (ESPAR) antenna can be used for 2-D direction-of-arrival (DoA) estimation employing received signal strength (RSS) values only. The proposed approach relies on changes in RSS values recorded at the antenna output port observed for different vertical and horizontal directions, while antenna’s main beam sweeps 360° area around the ESPAR antenna. Based...
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Performance of DS-CDMA Radionavigation Receiver with Subsample Time Measurement Resolution in Various Environments
PublicationThis paper presents results of investigation of position estimation performance in TDOA radionavigation system with receiver containing code tracking loop with subsample time measurement resolution. Position estimation accuracy was evaluated using real signals from CDMA base stations, recorded during measurement campaigns in various environments: on sea, flat terrain and hilly terrain.
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Plants sources of vitamins against SARS-CoV-2
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Using Evidence-based Arguments to Support Dependability Assurance-Experiences and Challenges
PublicationThe article introduces to the problem of evidence-based arguments and their applications. Then, based on the experiences collected during commercial deployment of a concrete solution to this problem (system NOR-STA) we overview selected challenges and the ways of addressing them
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Wpływ implementacji algorytmu Chana na jego efektywność
PublicationW referacie przybliżono algorytm Chana służący do wyznaczania położenia w metodzie TDOA. W algorytmie tym estymaty współrzędnych położenia można uzyskać w kilku różnych etapach wykonywania procedur algorytmu. Ponadto wątpliwość budzi sposób wypełniania macierzy B. W referacie zbadano dokładność uzyskiwanych estymat położenia w zależności od sposobu implementacji algorytmu Chana.
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Verification of ESPAR Antennas Performance in the Simple and Calibration Free Localization System
PublicationThis paper presents the results of simulations and measurements of an indoor localization system that uses Electronically Steerable Parasitic Array Radiator (ESPAR) antennas with switched directional beam. Proposed antennas are dedicated for 2.4GHz ISM low-cost applications where determination of the incoming signal is required. The antennas performance is analyzed and verified with relation to positioning methods based on the...
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Direction of Arrival Estimation Based on Received Signal Strength Using Two-Row Electronically Steerable Parasitic Array Radiator Antenna
PublicationIn this paper, we present a novel approach to direction-of-arrival (DoA) estimation using two-row electronically steerable parasitic array radiator (ESPAR) antenna which has 12 passive elements and allows for elevation and azimuth beam switching using a simple microcontroller, relying solely on received signal strength (RSS) values measured at the antenna output port. To this end, we thoroughly investigate all 18 available 3D antenna...
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Dokładność określania pozycji odbiornika w systemie radionawigacyjnym z niepewną pozycją nadajników
PublicationReferat zawiera analizę pracy algorytmu określania pozycji stacji bazowych w systemie radionawigacyjnym na podstawie serii pomiarów TDOA obarczonych błędami oraz wpływu błędów oszacowania pozycji stacji bazowych na późniejszą dokładność określania pozycji odbiornika na bazie pomiarów zależności czasowych sygnałów z tych stacji. Analiza jest oparta na wynikach pomiarów w eksperymentalnym morskim systemie nawigacyjnym AEGIR.
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Hyperbolic position location estimation in the multipath propagation environment
PublicationThe efficiency analysis a hyperbolic position location estimation in the multipath propagation environment in the wideband code division multiple access (WCDMA) interface was presented. Four, the most popular methods: Chan's, Foy's, Fang's and Friedlander's were considered. These algorithms enable the calculation of the geographical position of a mobile station (MS) using the time differences of arrival (TDOA) between several base...
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The Optical Transport Network Control Based on SDN Architecture
PublicationThe aim of this publication is to present research results on the usability of the Software-Defined Networking concept to control transport networks. For this purpose, an easy-to-use connection scheduler was developed capable of controlling connections in optical transport networks. The authors would like to present this solution and details of constructed SDN architecture implemented for modern optical transport solutions based...