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Search results for: SOUND INTENSITY MEASUREMENTS
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Role of various parametres in automatic classification of musical instrument sound.
PublicationArtkuł dotyczy problemu automatycznej klasyfikacji dźwięków instrumentów muzycznych, w tym głównie wpływu indywidualnych parametrów na proces automatycznego rozpoznawania instrumentów. Parametryzacja wykorzystuje wdirmo Fourierowskie i analizę czasową dźwięków do formowania 14 i 62-parametrowych wektorów cech dystynktywnych. Autorzy porównują jakość rozpoznawania i rozróźnialność instrumentów. Przy ocenach tego typu stosowano drzewa...
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Sound velocity and parameter of nonlinearity in the two-component relaxing mixtures
PublicationRozpatruje się własności akustyczne mieszanki dwuskładnikowej zawierającej gaz doskonały i parę cieczy bądź pył ciała stałego. Dokładne obliczenia pozwoliły na wyprowadzenie prędkości dźwięku i parametru nieliniowości jako funkcji koncentracji jednej ze składowych mieszaniny przy zadanych warunkach równowagowych. Przedstawiono wzory ogólne oraz symulacje numeryczne.
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Comparing some convolution-based methods for creation of surround sound
PublicationW referacie przedstawiono eksperymenty związane z symulacją dźwięku dookólnego w sali koncertowej. W tym celu wykorzystano splot odpowiedzi impulsowej z danego wnętrza (wielokanałowe nagrania odpowiedzi impulsowej) z nagraniami z komory bezechowej. Uzyskany w ten sposób sygnał został następnie przypisany do odpowiednich kanałów w systemie dookólnym. Uzyskane w ten sposób nagrania były następnie porównywane w testach subiektywnych...
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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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Linearization in impedance measurements
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Density, sound velocity, viscosity, and refractive index of new morpholinium ionic liquids with amino acid-based anions: Effect of temperature, alkyl chain length, and anion
PublicationIn this work, room temperature synthesis of twenty new ionic liquids (ILs) based on the N-alkyl-N-methylmorpholinium ([Mor1,R], R = 2, 3, 4, 6, 8) cation and N-acetyl-L-amino acid anions (L-alaninate, L-valinate, L-leucinate, L-isoleucinate) was described. The synthesized ILs were characterized by various spectroscopic techniques and high-resolution mass spectrometry. Furthermore, density (ρ), sound velocity (v), viscosity (η)...
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Intensity Ratio of Kβ/Kα in Selected Elements from Mg to Cu, and the Chemical Effects of Cr Kα1,2 Diagram Lines and Cr Kβ/Kα Intensity Ratio in Cr Compounds
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A scale with ECG measurements capability for home cardiac monitoring
PublicationPresented device -a scale developed for enabling extra measurements, in addition to body weight and composition, the electrical activity of the heart (electrocardiogram - ECG) and the level of oxygen saturation in the blood SaO2. Electrical activity is recorded in the form of six leads, socalled - limb leads. The device allows measurement of all standard limb leads and without the need for additional procedures. ECG, although the...
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Verification of GNSS Measurements of the Railway Track Using Standard Techniques for Determining Coordinates
PublicationThe problem of the reproduction of the railway geometric layout in the global spatial system is currently solved in the form of measurements that use geodetic railway networks and also, in recent years, efficient methods of mobile positioning (mainly satellite and inert). The team of authors from the Gdańsk University of Technology and the Maritime University in Gdynia as part of the research project InnoSatTrack is looking for...
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Analysis of the possibilities in railways shape assessing using GNSS mobile measurements
PublicationIn recent years, a dynamic development of satellite positioning techniques using both static and mobile GNSS coordinates register mode can be observed. In addition, still developing Real-time GNSS Networks, post-processing algorithms and another measurement signal analysis algorithms, make the satellite measurements increasingly used in railway industry sector. In the article the possibilities which follows from the mobile satellite...
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Study on the applicability of the measurements of magnetoelastic properties for a nondestructive evaluation of thermally inducted microstructure changes in the P91 grade steel
PublicationThe paper presents the resuIts of the investigation of the influence of duration and temperature oftempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steeI. Duringtempering of martensitic steels the dislocation density. which initially is very high. systematicallydecreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardnessmeasurements. Magnetic hysteresis...
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Displacement measurements during load testing of railway arch bridge
PublicationThe paper discusses issues concerning load tests carried out on a twin-track, arch railway bridge over the Martwa Wisla river in Gdansk. Currently, it is the bridge with the longest span in its class in Poland. The load-bearing structure consists of three no-hinge arches and an orthotropic deck suspended from them. The studies of the structure assumed the performing of static and dynamic tests. The paper presents the method for...
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Analyzing the Geometry of the Turnouts and Their Adjustment Basing on the Tacheometer Measurements
PublicationThe article presents the results of tacheometric measurements of a station throat, as well as the method of data preparation and analysis. The calculations covered the verification of the geometry and the location of railway turnouts and crossings. The analyses were performed for the selected parameters of the turnout geometry, including their lengths and track gauge in main sections. In addition, the data were analyzed to confirm...
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Design of reverse curves adapted to the satellite measurements
PublicationThe paper presents a new method for designing railway route in the direction change area adapted to the Mobile Satellite Measurements technique. The method may be particularly useful in the situations when both tangents cannot be connected in an elementary way using a circular arc with transition curves. Thus, the only solution would be the application of two circular arcs of opposite curvature signs, that is, the use of an inverse...
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Implementation of constant component filter in measurements of random telegraph signal noise
PublicationNoise is generated in all semiconductor devices. The intensity of these fluctuations depends on used elements, manufacturing process, operating conditions and device type. The result noise is a superposition of different kinds of fluctuations like thermal noise, generation-recombination noise, 1/f noise, shot noise and Random Telegraph Signal (RTS) noise. The last one, RTS noise is observed as nonstationary impulse fluctuations....
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Multi-Taper-Based Automatic Correction of Non-Anechoic Antenna Measurements
PublicationPrototype measurements belong to the key steps in the development of antenna structures. Although accurate validation of their far-field performance can be realized in dedicated facilities, such as anechoic chambers, the high cost of their construction and maintenance might not be justified if the main goal of measurements is to support teaching or low-budget research. Instead, they can be performed in non-anechoic conditions and...
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THE APPLICATION EFFECTS OF CONTINUOUS SATELLITE MEASUREMENTS OF RAILWAY LINES
PublicationThe paper presents results of satel lite surveying of the railway's rout es, which have been conducted just after starting in Poland (in 2008) the Active Geodesy Network ASG-EU POS. Afterwards it was possible to effectively utilize the GNSS survey ing results for the inventory of the (exploring) railways in service. Already at the beginning of 2009, the research team from Gdansk University of Technology and Naval Academy in Gdynia,...
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A telemedical and an outpatient thoracic impedance measurements - a validation algorithm of the electrodes placement
PublicationThis paper presents the algorithm for validation of electrodes locations for the thoracic impedance measurements. In particular the presented algorithm was designed to perform the telemetric sleep apnea monitoring. One of the problems, during the clinical tests of a developed device, was to preserve the repeatability of measurements. It strongly depended on the appropriate electrodes placement on the examined person’s thorax. It...
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Measurements of acoustic crosstalk cancellation efficiency in mobile listening conditions
PublicationThe cancellation of acoustic crosstalk is employed to enhance the stereo image in mobile listening conditions. The implementation of the crosstalk cancellation algorithm in Matlab is introduced. The measurement signals and equipment are described. A practical setup employing a mobile computer and a head and torso simulator is employed. The results of the measurements provided conclusions regarding the employment of acoustic crosstalk...
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Notch fatigue analysis and life assessment using an energy field intensity approach in 7050-T6 aluminium alloy under bending-torsion loading
PublicationThis paper studies the fatigue crack initiation and fatigue crack propagation of notched cylindrical bars made of 7050-T6 aluminium alloy subjected to multiaxial bending-torsion loading. The sites of crack initiation and the angles of crack initiation were successfully predicted from the distribution of the first principal stress at the notch surface. Fatigue crack initiation lives were computed through the new concept of energy...
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Analysis of the influence of ferromagnetic contaminations in plastics on the measurements of disturbances of magnetic field of the Earth
PublicationPlastics can be contaminated with small particles or filings with ferromagnetic properties. These contaminations cause significant disturbances in the magnetic field in the case of taking measurements of very low magnetic fields. The analysis of the influence of contaminated plastics on magnetic measurements is presented in this paper.
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Measurements of ASON/GMPLS connection control layer performance according to the ETSI methodology
PublicationMeasurements of performance have always been crucial for evaluation of telecommunication systems, especially for implementation of network control elements responsible for connection handling which regards to bandwidth reservation, modification and release. That problem also arises in Automatically Switched Optical Network/Generalized Multiprotocol Label Switching (ASON/GMLPS) architecture, which is considered as one of the components...
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Determination of nine high-intensity sweeteners in various foods by high-performance liquid chromatography with mass spectrometric detection
PublicationAn analytical procedure involving solid-phase extraction (SPE) and high-performance liquid chromatography-mass spectrometry has been developed for the determination of nine high-intensity sweeteners authorised in the EU; acesulfame-K (ACS-K), aspartame (ASP), alitame (ALI), cyclamate (CYC), dulcin (DUL), neohesperidin dihydrochalcone (NHDC), neotame (NEO), saccharin (SAC) and sucralose (SCL) in a variety of food samples (i.e. beverages,...
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On the light intensity dependence of short-circuit current of bilayer organic photovoltaic cells
PublicationPraca przedstawia model zależności prądu zwarcia w organicznych dwuwarstwowych układach fotowoltaicznych od natężenia światła. Model jest oparty na założeniu jednorodnego pola elektrycznego w obu warstwach organicznych. Uwzględniona jest bimolekularna i monomolekularna rekombinacja nośników ładunku przy heterozłączu. Przedstawione zostało porównanie obliczeń teoretycznych i wyników doświadczalnych dla układów z barwnikiem perylenowym...
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Effect of maximal-intensity exercise on systemic nitro-oxidative stress in men and women
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The effect of plate size on the natural convective heat transfer intensity of horizontal surfaces
PublicationW pracy przedstawiono badania wpływu rozmiarów płyty prostokątnej poziomej na intensywność wymiany ciepła w warunkach konwekcji swobodnej. Zaproponowano dwa zakresy: dla płyt o wymiarze charakterystycznym mniejszym niż 0,1 m - 0,2 m intensywność konwekcyjnej wymiany ciepła jest odwrotnie proporcjonalna do szerokości płyty, dla płyt szerszych niż 0,2 m szerokość płyty nie wpływa znacząco na współczynnik konwekcyjnej wymiany ciepła....
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Determination of time delay between ventricles contraction using impedance measurements
PublicationThe paper presents a novel approach to assessment of ventricular dyssynchrony basing on multichannel electrical impedance measurements. Using a proper placement of electrodes, the sensitivity approach allows estimating time difference between chambers contraction from over determined nonlinear system of equations. The theoretical considerations which include Finite Element Method simulations were verified using measurements on...
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The analysis of tram tracks geometrical layout based on Mobile Satellite Measurements
PublicationIn this article, the results of the research in a field of which uses active global navigation satellite system (GNSS) geodetic networks for the inventory of geodetic geometric tram tracks are presented. The applied measurement technique has been adapted for the designing of the geometric layout of tram tracks. Several configurations of receivers and settings of an active GNSS networks with the objective to increase the accuracy...
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Comparison of road and laboratory measurements of tyre/road noise
PublicationTyre/road noise is one of the major environmental problems related to road traffic. There are several measuring methods of tyre/road noise that may be carried out on the road (for example Coast-down and Close Proximity Method) or in the laboratory (Drum Method). Road measurements are preferred for evaluations of pavement properties while laboratory methods are mostly used to evaluate tyres. One of the biggest problems associated...
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Underwater Navigation Ssystem Based on Doppler Shift – Measurements and Error Estimations
PublicationA new acoustic navigation system was developed to determine the position and speed of moving underwater objects such as divers and underwater vehicles. The path of an object and its speed were determined by the Doppler shifts of acoustic signals emitted by a transmitter placed on the object and received by four hydrophones installed at the periphery of the monitored body of water. The position and speed measurements were affected...
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Fiber-optic Fabry-Pérot sensors – modeling versus measurements results
PublicationThis paper describes how parameters of investigated substances and the fiber-optic Fabry-Pérot sensing interferometer affect the spectrum of the optical radiation at the output of the sensor. First, the modeling of the operation of the sensing interferometer was conducted. Most important parameters and effects that were taken into account are: dependences of the refractive indices of the core and the cladding, as well the mode...
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Investigation of the Few‐Layer Black Phosphorus Degradation by the Photonic Measurements
PublicationFew-layer black phosphorus (FLBP) is a 2D material that gains worldwide interest for its possible applications, mainly in electronics and optoelec-tronics. However, as FLBP is prone to a degradation process under envi-ronmental conditions, there is a need for a monitoring method allowing investigation of its surface quality. Among many techniques, optoelectronic ones have unique advantages of fast response, non-contact, and non-invasive...
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Noise measurements on low noise pavements - problems with inhomogeneity of wearing course
PublicationDuring the last several years, when performing numerous CPX noise measurements on low noise pavements,significant inhomogeneity of the wearing course was observed in numerous cases. Similar problems were almost not existing regarding to the dense pavements.In general three main reasons of inhomogeneity can be defined. The first one are imperfections in technology of production of a asphalt mix or/and errors made already during...
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System setup and software for cyclic, staircase and square wave voltammetry measurements
PublicationHardware dedicated for electrochemical measurement sometimes does not allow performing certain voltammetry experiments. Staircase and square wave voltammetry, techniques which have many advantages comparing with standard voltammetric techniques, are rarely implemented in software controlling electrochemical measuring equipment. These methods, however, can be relatively easy realized with some addition...
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Reliability of acicular grindable thermocouples for transient temperature measurements at sliding contacts
PublicationAcicular grindable thermocouples represent an interesting and prospective technique of temperature measurements at sliding contacts. This study aimed at the investigation of their reliability and accuracy as applied to the friction materials of various classes in contact with steel. The tests were conducted on a pin-on-disc tribometer under stationary and transient regimes. The experimental results were validated by comparing the...
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Inhomogeneity of low-noise wearing courses evaluated by tire/road noise measurements using the close-proximity method
PublicationPerforming numerous analyses of tire/road noise measurements on low-noise pavements during the last several years, the authors observed significant inhomogeneity of the wearing course in numerous cases, while similar problems were almost non-existent when dense pavements were measured. Three main causes of low-noise pavement inhomogeneity can be defined. The first one is imperfections in the technology used for asphalt mix production...
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Dangerous sound event recognition using Support Vector Machine classifiers
PublicationA method of recognizing events connected to danger based on their acoustic representation through Support Vector Machine classification is presented. The method proposed is particularly useful in an automatic surveillance system. The set of 28 parameters used in the classifier consists of dedicated parameters and MPEG-7 features. Methods for parameter calculation are presented, as well as a design of SVM model used for classification....
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Automatic labeling of traffic sound recordings using autoencoder-derived features
PublicationAn approach to detection of events occurring in road traffic using autoencoders is presented. Extensions of existing algorithms of acoustic road events detection employing Mel Frequency Cepstral Coefficients combined with classifiers based on k nearest neighbors, Support Vector Machines, and random forests are used. In our research, the acoustic signal gathered from the microphone placed near the road is split into frames and converted...
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Estimation of musical sound separation algorithm effectiveness employing neural networks.
PublicationŚlepa separacja dźwięków sygnałów muzycznych zawartych w zmiksowanym materiale jest trudnym zadaniem. Jest to spowodowane tym, że dźwięki znajdujące się w relacjach harmonicznych mogą zawierać kolidujące składowe sinusoidalne (składowe harmoniczne). Ewaluacja wyników separacji jest również problematyczna, gdyż analiza błędu energetycznego często nie odzwierciedla subiektywnej jakości odseparowanych sygnałów. W tej publikacji zostały...
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Dental Condition as A Factor Modifying the Transmission of the Sound Vibration in the Skull Bones
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Investigation of influence of space mopdes interaction on nonlinear dynamics of sound beams
PublicationOperatory rzutu na mody są zdefiniowane w dynamice płynów trójwymiarowych. Zostały wyprowadzone równania ewolucyjne. Rezultaty obliczeń numerycznych przedstawione.
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Comparison of effectiveness of musical sound separation algorithms employing neural networks.
PublicationNiniejszy referat przedstawia kilka algorytmów służących do separacji dźwięków instrumentów muzycznych. Zaproponowane podejście do dekompozycji miksów dźwiękowych opiera się na założeniu, że wysokość dźwięków w miksie jest znana, tzn. wejściem dla algorytmów jest przebieg zmian wysokości dźwięków składowych miksu. Proces estymacji fazy i amplitudy składowych harmonicznych wykorzystuje dopasowywanie zespolonych przebiegów harmonicznych...
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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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Three electrode configuration measurements of electrolyte-diffusion barrier-cathode interface
PublicationMeasurements of a system consisting of cathode/doped ceria diffusion barrier/doped zirconia electrolyte were made using two- and three-electrode configuration. Results obtained on a three-electrode measurement configuration were compared with and reflect the results obtained in two-electrode configuration. Three-electrode measurements allowed separating the impact of the symmetrical interface in the investigated system. They also...
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Dead-Time Effect Compensation Based on Additional Phase Current Measurements
PublicationThis paper proposes a new method of dead-time effect compensation. The proposed solution is based on additional phase current measurements realized by analog-to-digital converters. These measurements are carried out at the time instants specified by a pulsewidth-modulation (PWM) strategy. This makes it possible to estimate inverter currents at the commutation instants and, finally, to estimate the voltage error caused by dead time. This...
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Accuracy of marine gravimetric measurements in terms of geodetic coordinates of land reference benchmark
PublicationThe article presents how the values of (3D) coordinates of land reference points affect the results of gravimetric measurements made from the ship in sea areas. These measurements are the basis for 3D maritime inertial navigation, improving ships' operational safety. The campaign verifying the network absolute point coordinates used as a reference point for relative marine gravity measurements was described. The obtained values...
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Accurate rolling resistance Rolling resistance measurements can be influenced by a number of factors
PublicationTire rolling resistance is one of the most difficult-to-measure parameters of the tire/ pavement interface, especially if road measurements are required. First of all, it is necessary to measure a fairly small force in the system that is heavily loaded by other forces and subjected to many adverse effects causing measurement errors. The second problem is related to the fact that tire rolling resistance depends on many factors,...
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EXHAUST TEMPERATURE MEASUREMENTS OF THE MARINE TURBOCHARGED DIESEL ENGINES IN OPERATION
PublicationThe article presents the selected metrology issues concerning the exhaust temperature of the turbocharged marine engines during operation. The special concern has been paid on existing disturbances as well as thermodynamical interpretation of the recorded measurement signal. A diagnostic informativeness of the standard exhaust temperature’s measurements has worked out while the engine runs in steady states has been also considered...
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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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A Low-Cost System for Far-Field Non-Anechoic Measurements of Antenna Performance Figures
PublicationPrototype measurements are the key step in the development of antenna structures. Typically, their far-field characteristics are validated in expensive, dedicated facilities such as open range sites, or anechoic chambers. Despite being necessary for obtaining high-precision data (e.g., for device qualification), the use of costly infrastructure might not be fully justified when the main goal of measurements includes demonstration...