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Search results for: sygnaly impulsowe
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Testing method of analog parts for mixed signal microsystems based on microcontrolles.
PublicationZaproponowano nową metodę detekcji i lokalizacji pojedynczych uszkodzeń parametrycznych, która może znaleźć zastosowanie do samo-testowania sieci analogowych w mikrosystemach mieszanych sygnałowo sterowanych mikrokontrolerami. Metoda ta jest oparta na przekształceniu transformującym próbki odpowiedzi czasowej na pobudzenie impulsem prostokątnym na krzywe identyfikacyjne na płaszczyźnie. Metoda pozwala na detekcję i lokalizację...
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A Modeling Problem of a Continuous-Time Domain Signal and Its Discrete Counterpart
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Estimation of the amplitude of the signal for the active optical gesture sensor with sparse detectors
PublicationIn this paper we deal with the problem of precise gesture recognition for the active optical proximity sensor with sparse 8 photodiodes. We particularly focus on developing the method of estimating the real, usually not observable, maximum signal value representing maximum intensity of light reflected from an obstacle present in the front of the sensor. Different configurations of the fingers were used as an obstacle. The Monte Carlo...
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Separation of the effects of notch and macro residual stress on the MFL signal characteristics
PublicationMagnetic flux leakage (MFL) distribution for three configurations of samples has been investigated in order to study the influence of notch and plastic deformation separately as well as together. Samples have been made of S355 steel. The MFL signal measurements were carried out along the longest dimension of the sample over a length of 120 mm. Two components of magnetic field were measured: 1) tangential to the main axis and 2)...
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Usage of the Gstreamer framework for generation, analysis, processing and visualization of sonar signal
PublicationIn this paper a novel method of the bearing estimation in a passive sonar system with a towed array is introduced. The classical approach of the bearing estimation based on the spatial spectrum is extended by using the synchrosqeezing method that is a part of the reassignment method introduced by Kodera et al. The usage of this method leads to the precise bearing estimation. The proposed method requires a relatively small amount...
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Local dynamics of fluids and dielectrics as the foundation of signal-carrying wave properties
PublicationThis paper develops an original approach to fundamental problems of classical linear acoustics and electromagnetics, proving a crucial role of doubly-dynamic local properties of a propagation medium in supporting wave-like fields able to carry information signals. The proof is composed of two steps concerning, subsequently, fluid acoustics and dielectric electromagnetics. The first step consists in complementing a common, practically...
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Fast High-Impedance Spectroscopy Method Using SINC Signal Excitation
PublicationIn this paper the method of fast impedance spectroscopy of technical objects with high impedance (|Zx| > 1 Gohm) is evaluated by means of simulation and practical experiment. The method is based on excitation of an object with a sinc signal and sampling response signals proportional to current flowing through and voltage across the measured impedance. The object impedance spectrum is obtained with use of continuous Fourier transform...
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A diagnosis method of analog parts of mixed-signal systems controlled by microcontrollers.
PublicationPrzedstawiono nową klasę K-D metod diagnostyki analogowych części mieszanych sygnałowo mikrosystemów bazujących na mikrokontrolerach. Metody składają się z trzech etapów: etapu przedtestowego tworzenia słownika uszkodzeń, etapu pomiarowego bazujacego na pomiarach próbek napięcia odpowiedzi układu analogowego na pobudzenie impulsem prostokątnym wykonywanych przez wewnętrzne zasoby mikrokontrolera i z etapu detekcji i lokalizacji...
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Ground-based, Hyperbolic Radiolocation System with Spread Spectrum Signal - AEGIR
PublicationThe most popular radiolocation systems in the world (at present), is the American GPS (Global Positioning System). It is managed by the Department of Defense and there is always the possibility of the occasional inaccuracies or deliberate introduction of errors that prevent its use by the special services or armies of other countries than the U.S.A. This situation has spawned the need to develop an autonomous, ground-based radiolocation...
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Self-optimizing narrowband interference canceller - can reference signal help?
PublicationSONIC (Self-Optimizing Narrowband Interference Canceller) is an acronym of the recently proposed active noise control algorithm with interesting adaptivity and robustness properties. SONIC is a purely feedback controller, capable of rejecting nonstationary sinusoidal disturbances (with time-varying amplitudes and/or frequencies) in the presence of plant (secondary path) uncertainties. We show that even though SONIC can work reliably...
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Narrowband Transmission Quality in Presence of Modified IEEE 802.15.4a UWB Signal
PublicationThis paper presents results of measurement of narrowband transmission quality in presence of impulse radio UWB interference. In the first part of paper, unmodified IEEE 802.15.4a IR UWB signal is used. Then some modification of transmitted pulse sequence is proposed, which allow to reduce UWB power spectral density at frequency of narrowbandtransmission. Finally narrowband transmission quality in presence of modified ultrawideband...
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Accuracy analysis of the RSSI BLE SensorTag signal for indoor localization purposes
PublicationIn this paper we describe possibility of use the RSSI signal (Radio Signal Strength Indication) from Texas Instruments SensorTag CC2650 for indoor positioning purposes. This idea is not a new but in our opinion it is possible to use SensorTags with Bluetooth LE wireless interface for positioning inside buildings in such applications as people findings in hospitals, senior come care, etc. RSSI is mostly selected as the sensor localization...
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Signal conditioning for examination of shallow-water acoustic noise correlation properties
PublicationThe article describes the process of signal conditioning for examination of acoustic noise correlation properties in shallow water. Knowledge of these properties is very important for the design processes of passive and active hydroacoustic systems. This paper focuses on the above issue from the point of view of passive sonar. In sonar systems, signal processing algorithms operate on both useful acoustic signals, and accompanying...
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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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Probe signal processing for channel estimation in underwater acoustic communication system
PublicationUnderwater acoustic communication channels are characterized by a large variety of propagation conditions. Designing a reliable communication system requires knowledge of the transmission parameters of the channel, namely multipath delay spread, Doppler spread, coherence time, and coherence bandwidth. However, the possibilities of its estimation in a realtime underwater communication system are limited, mainly due to the computational...
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QRS Morphology-Based EDR Signal—Factors Determining its Properties
PublicationRespiration-induced signals contain a clinically significant information. It could be obtained utilizing both direct and indirect methods. ECG-Derived Respiration (EDR) method is the latter one. However, in this case, two approaches could be distinguished. First one is based on determining changes in the morphology of QRS complexes while the second one is based on the Respiratory Sinus Arrhythmia (RSA) mechanism. The former approach...
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Wideband Signal Generation for Jamming Radio-Controlled Improvised Explosive Devices
PublicationThis paper focuses on modelling operation of a wideband jamming signal generator, considering the effects present in real device which influence the shape of transmitted signal’s spectrum. Introduction is followed by a brief overview of AEGIS project, aim of which is to develop a mobile generator of electromagnetic curtain. Next, simulation model is described which includes the factors...
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Determining Pronunciation Differences in English Allophones Utilizing Audio Signal Parameterization
PublicationAn allophonic description of English plosive consonants, based on audio-visual recordings of 600 specially selected words, was developed. First, several speakers were recorded while reading words from a teleprompter. Then, every word was played back from the previously recorded sample read by a phonology expert and each examined speaker repeated a particular word trying to imitate correct pronunciation. The next step consisted...
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Signal Propagation in Electromagnetic Media Modelled by the Two-Sided Fractional Derivative
PublicationIn this paper, wave propagation is considered in a medium described by a fractional-order model, which is formulated with the use of the two-sided fractional derivative of Ortigueira and Machado. Although the relation of the derivative to causality is clearly specified in its definition, there is no obvious relation between causality of the derivative and causality of the transfer function induced by this derivative. Hence, causality...
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Signal Reconstruction from Sparse Measurements Using Compressive Sensing Technique
PublicationThe paper presents the possibility of applying a new class ofmathematical methods, known as Compressive Sensing (CS) for recovering thesignal from a small set of measured samples. CS allows the faithful recon-struction of the original signal back from fewer random measurements bymaking use of some non-linear reconstruction techniques. Since of all thesefeatures, CSfinds its applications especially in the areas where, sensing is...
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TIME- AND FREQUENCY-DOMAIN QUASI-2D SMALL-SIGNAL MOSFET MODELS
PublicationA novel approach to small-signal MOSFET modeling is presented in this book. As a result, time- and frequency-domain physics-based quasi-2D NQS four-terminal small-signal MOSFET models are proposed. The time-domain model provides the background to a novel DIBL-included quasi‑2D NQS four-terminal frequency-domain small-signal MOSFET model. Parameters and electrical quantities of the frequency-domain model are described by explicit...
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Signal filtering method of the fast-varying diesel exhaust gas temperature
PublicationThe paper presents the problem of the impact of external distortions originating on laboratory test stands on the results of measurements of fast-varying diesel exhaust gas temperature. It has been stressed how significant the aspect of the test stand adaptation is during an experiment to ensure the smallest possible impact. This paper, however, focuses on the methods of mathematical processing of a signal recorded during experimental...
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Data Compression in Ultrasonic Network Communication via Sparse Signal Processing
PublicationThis document presents the approach of using compressed sensing in signal encoding and information transferring within a guided wave sensor network, comprised of specially designed frequency steerable acoustic transducers (FSATs). Wave propagation in a damaged plate was simulated using commercial FEM-based software COMSOL. Guided waves were excited by means of FSATs, characterized by the special shape of its electrodes, and modeled...
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Operat akustyczny dla pomieszczeń w Wielofunkcyjnym Centrum Kultury w Wejherowie.
PublicationWykonano pomiary akustyczne sali widowiskowej i i pomieszczeń towarzyszących. Wykorzystano impulsowe źródło dźwięku (pistolet startowy), sygnał MLS wytwarzany przez zestaw głośników pomiarowych o charakterystyce dookólnej oraz przez aparaturę nagłośnieniową zainstalowaną w pomieszczeniach.
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Evaluation of Barkhausen Noise and Magnetoacoustic Emission Signals Properties for Plastically Deformed Armco Iron
PublicationArtykuł prezentuje wyniki badania wpływu różnych rodzajów deformacji plastycznej na właściwości magnetoakustyczne żelaza Armco. Badane były dwie serie próbek - pierwsza składała się ze wstępnie wyżarzonych próbek, które następnie były walcowane na zimno, w skład drugiej wchodziły natomiast próbki wycięte z komercyjnie dostępnej blachy wykonanej z żelaza Armco a następnie poddane obciążeniom rozciągającym. Walcowanie na zimno prowadzi...
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Hydrological signals in polar motion excitation – Evidence after fifteen years of the GRACE mission
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Optymalizacja sygnału testującego dla potrzeb identyfikacji modeli procesów biologicznych i medycznych
PublicationRozprawa poświęcona jest optymalizacji sygnału testującego dla celów identyfikacji modeli procesów biologicznych i medycznych. Zagadnienie to zawiera się w szerszym zagadnieniu optymalizacji eksperymentu, polegającym na poszukiwaniu tej wartości wybranej zmiennej eksperymentu (w rozprawie jest to sygnał testujący), która zapewni maksimum obranego kryterium optymalności. Optymalizacja eksperymentu jest szczególnie istotna w zastosowaniach...
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Higuchi fractal dimension analysis of surface EMG signals and determination of active electrode positions
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Nowy system cyfrowej transmisji sygnału mowy o szybkości 16 kbit/s
PublicationCelem pracy jest przedstawienie nowego systemu cyfrowej transmisji sygnału mowy wykorzystującego kanał cyfrowy o prędkości transmisji 16 kbit/s. Nowa metoda kodowania sygnału mowy zaproponowana w pracy pozwala zmniejszyć czterokrotnie, w porównaniu z telefonią cyfrową, wymaganą szybkość transmisji, przy zachowaniu akceptowanej jakości przesyłanej mowy, a jednocześnie nie wymaga drogich numerycznie algorytmów wykorzystywanych w...
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Cyfrowy system rejestracji i rekonstrukcji sygnału mowy dla potrzeb Lotnictwa Wojskowego.
PublicationW referacie przedstawiono ogólną charakterystykę opracowanego systemu rejestracji i rekonstrukcji sygnału mowy. Zamieszczono opis poszczególnych składników systemu, które stanowi zestaw zaawansowanych narzędzi do rejestracji, analizy i rekonstruowania mowy, zrealizowany w formie oprogramowania komputerowego. Narzędzia te pozwalają na szybkie wyszukiwanie pożądanych fragmentów nagrań oraz poprawę ich jakości na drodze redukcji szumów,...
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DMI measurements impact on a position estimation with lack of GNSS signals during Mobile Mapping
PublicationNowadays, Mobile Laser Scanning is common in use in addition to geodesy measurements. The data which are provided by the system characterizes with high precision and flexibility. To precise mapping, the accuracy of the data should be maintained. In Poland, according to the minister’s dispositions, the accuracy of the data should not exceeded 10 cm. With fully operated system it is easy to uphold, but there is a situation when a...
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Wykorzystanie algorytmu kompresji sygnału mowy MP-LPC do modelowania przebiegu fonokardiograficznego
PublicationW artykule przedstawiono nową metodę modelowania dźwięków serca, która może znaleźć zastosowanie w systemach diagnostyki urządzeń medycznych oraz stanowić podstawę opracowania inteligentnego stetoskopu. Przedstawiona propozycja stanowi rozwinięcie algorytmu MP-LPC wykorzystywanego w kompresji sygnału mowy. Wykazano, że do dokładnego modelowania przebiegu fonokardiograficznego, który pozwala na odwzorowywanie różnorodnych stanów...
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Signals Features Extraction in Radioisotope Liquid-Gas Flow Measurements using Autocorrelation Function
PublicationKnowledge of the two-phase flow structure is essential for the proper conduct of industrial processes. Description of liquid-gas flow regimes is possible by using of data analysis in time, frequency, or state-space domain. In this research studies, the autocorrelation function is applied for analysis of signals obtained for liquid-gas flow by use gamma-ray absorption. The experiments were carried out on the laboratory hydraulic...
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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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APPLICATION OF STATISTICAL FEATURES AND MULTILAYER NEURAL NETWORK TO AUTOMATIC DIAGNOSIS OF ARRHYTHMIA BY ECG SIGNALS
PublicationAbnormal electrical activity of heart can produce a cardiac arrhythmia. The electrocardiogram (ECG) is a non-invasive technique which is used as a diagnostic tool for cardiac diseases. Non-stationarity and irregu- larity of heartbeat signal imposes many difficulties to clinicians (e.g., in the case of myocardial infarction arrhythmia). Fortunately, signal processing algorithms can expose hidden information within ECG signal contaminated...
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Subjective Quality Evaluation of Speech Signals Transmitted via BPL-PLC Wired System
PublicationThe broadband over power line – power line communication (BPL-PLC) cable is resistant to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency. These features make it an ideal solution for delivering data, e.g. in an underground mine environment, especially clear and easily understandable voice messages. This paper describes a subjective quality evaluation of...
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Signals features extraction in radioisotope liquid-gas flow measurements using wavelet analysis
PublicationKnowledge of the structure of a flow is significant for the proper conduct of a number of industrial processes. In this case, a description of a two-phase flow regimes is possible by use of the time-series analysis in time, frequency and state-space domain. In this article the Discrete Wavelet Transform (DWT) is applied for analysis of signals obtained for water-air flow using gamma ray absorption. The presented method was illustrated...
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DOBÓR PARAMETRÓW FILTRACJI W CEPSTRUM DLA POTRZEB POPRAWY JAKOŚCI ODBIERANEGO SYGNAŁU
PublicationW referacie zaproponowano metodę eliminacji wpływu efektu wielodrogowości poprzez analizę i filtrację odbieranego sygnału w cepstrum. Analiza taka, pozwala na wykrycie istnienia repliki (echa) sygnału nadawanego oraz odfiltrowanie tej repliki, co poprawia jakość realizowanej transmisji sygnału. W referacie zaprezentowano wyniki badan symulacyjnych.
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Dwuetapowa metoda detekcji zakłóceń impulsowych w sygnałach fonicznych
PublicationW pracy zaproponowano dwuetapową metodę detekcji zakłóceń opartą o analizę funkcji gęstości rozkładu prawdopodobieństwa sygnału zakłóconego impulsowo. Określono sposób ustalenia poziomu wyzwalania detektora progowego.
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Improving signal quality of a speech codec using hybrid perceptual-parametric algorithm
PublicationW artykule zaprezentowano hybrydową architekturę parametryczno-perceptualną kodeka mowy. Jego podstawę stanowi kodek CELP, który wspomagany jest kodekiem perceptualnym. Celem zastosowania proponowanej metody jest uzyskanie poprawy jakości kodowania sygnału mowy. Badaniom poddano dwie architektury, z których w jednej dźwięczne części sygnału rezydualnego kodeka CELP kodowane są perceptualnie. Drugi z proponowanych kodeków dokonuje...
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Influence of accelerometer signal pre-processing and classification method on human activity recognition
PublicationA study of data pre-processing influence on accelerometer-based human activity recognition algorithms is presented. The frequency band used to filter-out the accelerometer signals and the number of accelerometers involved were considered in terms of their influence on the recognition accuracy. In the test four methods of classification were used: support vector machine, decision trees, neural network, k-nearest neighbor.
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Combined method of multibeam sonar signal processing and image analysis for seafloor classification
PublicationThe combined approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive...
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A digital implementation of the PSK transmitter and receiver as multirate algorithms of the digital signal processing
PublicationIn this paper designs of the transmitter and the receiver of PSK signals as three-rate algorithms of the digital signal processing are described. Additionally we show the examples of the transmitter and the receiver of the following signals: BPSK, QPSK. We discussed also an influence of the cascade of the shaping filter and the receiving filter on the intersymbol interference in the received complex envelope.W pracy opisano projektowanie...
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Modeling of a rock fall using the discrete element method and study of the seismic signal
PublicationW artykule przedstawiono opis fal sejsmicznych, zastosowanie dyskretnej metody elementów do opisu obrywu skalnego, opis programów obliczeniowych oraz obliczenia numeryczne wg. podanych programów obliczeniowych.
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Pitch estimation of narrowband-filtered speech signal using instantaneous complex frequency
PublicationIn this paper we propose a novel method of pitch estimation, based on instantaneous complex frequency (ICF). New iterative algorithm for analysis of ICF of speech signal in presented. Obtained results are compared with commonly used methods to prove its accuracy and connection between ICF and pitch, particularly for narrowband-filtered speech signal.
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Modeling of a rock fall using the discrete element method and study of the seismic signal
PublicationMechanizm dużego spadającego bloku skalnego lub lawiny pozostaje nadal słabo rozpoznany zarówno w zakresie pęknięć jak i procesów propagacji. Jedynie ilościowe dane, które aktualnie są mierzone i uchwytne podczas spadania skały, zarejestrowane są jako sejsmiczne sygnały przez szereg sejsmografów. Właściwości sygnału (amplituda, trwanie, częstotliwość) są wyraźnie powiązane z cechami spadania (masa, wysokość spadania, odległość...
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Application of TMS320c67xx signal processors for SONIC-self-optimizing narrowband interference canceler
PublicationThe paper presents a laboratory system for testing active control algorithms of acoustics noise in ducts. An applied algorithm - self-optimizing narrowband interference canceller (SONIC), allows one to remove narrowband disturbances of constant or slowly time-varying frequencies. Example experimental results of using the laboratory system for supression of sinusoidal disturbance are described. An electronic part of the system was...
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Seafloor characterisation using multibeam sonar echo signal processing and image analysis
PublicationThe authors propose the approach to multibeam seafloor characterisation which relies on the combined, concurrent use of two different techniques of multibeam sonar data processing. The first one is based on constructing the grey-level sonar images of seabed using the echoes received in the consecutive beams. Then, the parameters describing the local region of sonar image, namely, the local standard deviation of a grey level, and...
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Pitch estimation of narrowband-filtered speech signal using instantaneous complex frequency
PublicationIn this paper we propose a novel method of pitch estimation, based on instantaneous complex frequency (ICF). New iterative algorithm for analysis of ICF of speech signal in presented. Obtained results are compared with commonly used methods to prove its accuracy and connection between ICF and pitch, particularly for narrowband-filtered speech signal.
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AM Modulation Signal Estimation Allowing Further Research on Sources of Voltage Fluctuations
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