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Wyniki wyszukiwania dla: SINUSOIDAL PULSEWIDTH MODULATION
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Hybridized Space-Vector Pulsewidth Modulation for Multiphase Two-Level Voltage Source Inverter
PublikacjaIn space vector pulsewidth modulation (SVPWM) algorithms for multiphase two-level voltage source inverters (VSI), the components of active vectors in all orthogonal spaces have to be calculated within the processor and stored in its memory. These necessitate intensive computational efforts of the processor and large memory space. This article presents a hybridized SVPWM for multiphase two-level VSI. In this algorithm, elements...
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Space-vector pulsewidth modulation for a seven-level cascaded H-bridge inverter with the control of DC-link voltages
PublikacjaThe control strategy of DC-link voltages for a seven-level Cascaded H-Bridge inverter is proposed in this paper. The DC-link voltage balancing is accomplished by appropriate selection of H-Bridges and control of their duty cycles in Space-Vector Modulation (SVM) algorithm. The proposed SVM method allows to maintain the same voltage level on all inverter capacitors. Regardless of the balancing function, the...
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Space Vector Pulsewidth Modulation Strategy for Multilevel Cascaded H-Bridge Inverter With DC-Link Voltage Balancing Ability
PublikacjaSpace vector pulsewidth modulation (SVPWM) algorithms for cascaded H-bridge multilevel (CHB ML) inverter usually provide the possibility of using several combinations of active voltage vectors to generate the same output voltage vector. For preselected H-bridges, some of them may generate output voltages opposite to the assumed direction. This results in the change of the dc-link voltages of these H-bridges in the opposite direction...
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A Single-Carrier-Based Pulse-Width Modulation Template for Cascaded H-Bridge Multilevel Inverters
PublikacjaMultiplicity of the triangular carrier signals is a criterion for the extension of sinusoidal pulsewidth modulation, SPWM, to a number of output voltage levels per phase-leg in cascaded H-bridge (CHB) multilevel inverter (MLI). Considering medium and high voltage applications where appreciable number of output voltage levels from CHB MLI is needed, commensurate high number of carrier signals in either classical level- or phase-shifted...
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Hybridized PWM Strategy for Three- and Multiphase Three-Level NPC Inverters
PublikacjaA simple hybridized pulsewidth modulation (PWM) algorithm for three- and multiphase three-level neutral point clamped (NPC) inverters is proposed. The proposed solution is based on classical space vector PWM (SVPWM) algorithms for two-level inverters but can also be based on sinusoidal PWM with min–max injection. An additional level of output voltage is obtained by modifying the resulting switching patterns taking into account...
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Space vector modulation in multilevel inverters of the servo drives of the trajectory measurements telescopes
PublikacjaUsing the MatLab/Simulink mathematical model of a three-phase three-level voltage inverter, the influence of the space-vector modulation (SVM) algorithm on the pulsations of the current (torque) of an AC motor in the range of low rotation speeds is considered. It is shown that the SVM of the second kind does not provide a pulsations level comparable to the pulsations of a sinusoidal pulse-width modulation (SPWM), both in the static...
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Pulse-Width Modulation Template for Five-Level Switch-Clamped H-Bridge-Based Cascaded Multilevel Inverter
PublikacjaThis article presents a carrier-based pulse-width modulation (PWM) template for a 5-level, H bridge-based cascaded multilevel inverter (MLI). The developed control concept generates adequate modulation template for this inverter topology wherein a sinusoidal modulating waveform is modified to fit in a single triangular carrier signal range. With this modulation approach, classical multiplicity and synchronization of the triangular...
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Taguchi sensors under temperature modulation
PublikacjaSemiconductor gas sensors are widely used in gas- analyzing applications for various gas species determination due to their low cost and possibility to detect number of different gases. However, one of the main problems with such sensors is their lack of selectivity. To overcome this issue different ap- proaches can be used. One of them is the operation with sensor temperature modulation combined with dedicated data process- ing...
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Determination of chlorine concentration using single temperature modulated semiconductor gas sensor
PublikacjaA periodic temperature modulation using sinusoidal heater voltage was applied to a commercial SnO2 semiconductor gas sensor. Resulting resistance response of the sensor was analyzed using a feature extraction method based on Fast Fourier Transformation (FFT). The amplitudes of the higher harmonics of the FFT from the dynamic nonlinear responses of measured gas were further utilized as an input for Artificial Neural...
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Application of Analytic Signal and Smooth Interpolation in Pulse Width Modulation for Conventional Matrix Converters
PublikacjaThe paper proposes an alternative and novel approach to the PWM duty cycles computation for Conventional Matrix Converters (CMC) fed by balanced, unbalanced or non–sinusoidal AC voltage sources. The presented solution simplifies the prototyping of direct modulation algorithms. PWM duty cycles are calculated faster by the smooth interpolation technique, using only vector coordinates, without trigonometric functions and angles. Both...
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A New Approach to the PWM Modulation for the Multiphase Matrix Converters Supplying Loads with Open-End Winding.
PublikacjaThis article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load's terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion...
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Modified SPWM Technique with Zero-Sequence Voltage Injection for a Five-Phase, Three-Level NPC Inverter
PublikacjaThis article presents a modified sinusoidal pulse-width modulation (SPWM) scheme for a five-phase, three-level neutral-point-clamped inverter. The modulation scheme deploys a modified min–max function to inject the zero-sequence components into the reference modulating signals; hence enabling the effective utilization of the DC-link voltage. Balanced split-input DC-link voltages were achieved through further incorporation of adjustable...
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Dead-Time Effect Compensation Based on Additional Phase Current Measurements
PublikacjaThis 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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A Simplified SPWM Scheme for a Compact 3-Level Dual-Output Inverter
PublikacjaSinusoidal Pulse-width modulation, SPWM, is inverter-leg-based, logical-operation-based, and lesscomputational-intensive. In this brief, these simplifying features of SPWM are extended to the control of the 10-switch, 3-level inverter. The control strategy is based on the single triangular carrier SPWM perspective. Procedures and details of the sharing of four-common power switches by the 3 inverter legs are given. Classically,...
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A High-Efficient Measurement System With Optimization Feature for Prototype CMOS Image Sensors
PublikacjaIn this paper, a gray-scale CMOS image sensor (CIS) characterization system with an optimization feature has been proposed. By using a very fast and precise control of light intensity, based on the pulsewidth-modulation method, it is avoided to measure the illuminance every time. These features accelerate the multicriteria CIS optimization requiring many thousands of measurements. The system throughput is 2.5 Gb/s, which allows...
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Hybridized SVPWM Algorithm for Multilevel CHB Inverter With DC-Link Voltage Control Capability
PublikacjaThe deployment of a space vector pulsewidth modulation (SVPWM) scheme in controlling cascaded H-bridge multilevel inverter (CHB MLI) is quite challenging; especially, when a substantial number of output voltage levels are involved and the dc-link voltages are out of balance. In this article, a simple SVPWM algorithm for CHB MLI is proposed. In the proposed algorithm, all the H-bridges in an inverter phase are treated as a single...
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Single-phase, Five-level Inverter with SPWM-Based Neutral Point Voltage Balancing Scheme
PublikacjaMultilevel inverter topologies provide several advantages over two-level inverter configuration. These benefits are the reason for the growing interest in multilevel topologies among research society. One of the most popular topological concepts (diode and active switch clamping) requires neutral-point potential balancing due to series-connected capacitor banks across the input dc link in such derived inverter configurations. This...
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Feasibility Study of Three-Phase Modular Converter for Dual-Purpose Application in DC and AC Microgrids
PublikacjaThe modern concept of a universal converter is intended as a power converter (PC) suitable for application in both dc or ac grids using the same external connectors. This novel family was recently proposed to allow easier integration of renewable energy sources and energy storage systems (ESSs), interfacing with dc/ac grids and/or loads with a minimum redundancy of power switches and passive elements. This kind of solution and...
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Integrated Three-Level Dual-Phase Inverter
PublikacjaIn view of reducing the number of inverter legs that provide dual-phase, three-level output voltages (as may be needed in an uninterruptible power supply), and that also provide a wide range of output frequencies (as needed in an advanced motor drive system with wide speed ranges), a three-level, dual-phase inverter topology is presented in this paper. Its three-level attribute was based on the F-type inverter topological concept,...
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A Five-Leg Three-Level Dual-Output Inverter
PublikacjaClassical 3-level dual-output inverter, 3-L DOI, involves two similar 3-level inverters that provides a pair of 3-phase output voltages with same or different frequencies from common input voltage source. Flexibility of either operation of the constituting inverters is evident in this DOI; but total duplication of power switches is a major drawback. State of the art coupled 3-L DOIs reduce this drawback by providing series-shared...
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FFT analysis of temperature modulated semiconductor gas sensor response for the prediction of ammonia concentration under humidity interference
PublikacjaThe increasing environmental contamination forces the need to design reliable devices for detecting of the volatile compounds present in the air. For this purpose semiconductor gas sensors, which have been widely used for years, are often utilized. Although they have many advantages such as low price and quite long life time, they still lack of long term stability and selectivity. Namely, environmental conditions have significant...
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Computer System for Evaluation of Shock Hazard in Circuits with Non-sinusoidal Earth Currents
PublikacjaEffects of current on people are mainly considered for 50/60 Hz sinusoidal current and smooth direct current. However, modern low voltage circuits are very often equipped with power electronics converters – rectifiers, frequency converters, therefore non-sinusoidal earth currents (touch currents) occur. For non-sinusoidal currents safety criteria should be modified. This paper presents a computer system, based on LabVIEW environment,...
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GAS SENSORS WITH TEMPERATURE MODULATION – AN OVERVIEW
PublikacjaAlthough different methods of improving semiconductor gas sensor properties have been proposed, a technique involving temperature modulation seems to be the most promising. Semiconductor gas sensors working with modulated temperature can be more stable and are more selective comparing with sensor working at one temperature. In this paper, various approaches to temperature modulation are reviewed.
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Zero phase shift digital filtering for assessment of exposure to non-sinusoidal magnetic fields
PublikacjaAccuracy of assessment of human body exposure to magnetic fields is affected by several uncertainty sources. One of them is estimation of the total exposure to non-sinusoidal fields. Standard methods can be implemented using analogue or digital filters that introduce a phase shift that affect the result of total exposure level estimation. The paper presents a new method that allows performing more precise assessment of exposure...
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Sinusoidal Alternating-Current Voltammetry and Metrological Properties of a Flat Voltammetric Electrode in the Time Domain
PublikacjaIn this paper there were analyzed metrological properties of a flat electrode used to mark ions with the method of sinusoidal alternating-current voltammetry in the situation where on its surface an electrochemical reversible reaction of oxidizing / reduction takes place. The result of the analysis conducted is that such a voltammetric electrode functions like a converter type I. Metrological properties of such an electrode in...
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Hybrid Modulation for Modular Voltage Source Inverters with Coupled Reactors
PublikacjaThis paper proposes and discusses a concept of a hybrid modulation for the control of modular voltage source inverters with coupled reactors. The use of coupled reactors as the integrating elements leads to significant reduction in the size and weight of the circuit. The proposed modulation combines novel coarsely quantized pulse amplitude modulation (CQ-PAM) and innovative space-vector pulse width modulation (SVPWM). The former...
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Evaluation of Selected Modulation Techniques in Underwater Multipath Channel
PublikacjaThere is a growing interest in the use of Autonomous Underwater Vehicles (AUVs) and Underwater Sensor Networks (USNs) for scientific, military, and industrial applications, leading to the development of wireless underwater communications. However, the channel for Underwater Acoustic (UWA) communications is challenging compared to the radio wave propagation in the air. Especially in shallow waters, where the channel has strong multipath...
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Noise effect on parameters of quiet sonar with code modulation
PublikacjaEarlier publications of the paper authors have shown that the use of code keying mixed with the CW FM sound signal allows the significant reduction in the distance measurement error, compared to classic silent CW FM sonar. In addition to the code modulation parameters, the magnitude of this error is influenced by the received input acoustic noise. The article shows the dependence of the input signal-to-noise ratio and the sound...
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Tripping of F-type RCDs for sinusoidal residual current with superimposed smooth DC component
PublikacjaRecent trends in green energy development make that photovoltaics and electric vehicles are applied on an increasing scale. In both photovoltaic and electric vehicle charging installations, a significant value of DC component of the earth fault current may appear, which is a challenge, in particular, for commonly used residual current devices (RCDs). This paper presents results of the laboratory test on the operation of F-type...
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Analysis of distance measurement errors in CW FM sonar with MLS code modulation
PublikacjaAlthough used in the classic silent sonar, the CW FM sounding signal has a major flaw which is its inaccuracy in determining the distance to a target. The authors of the article have developed a concept of silent sonar using frequency modulation signals switched by pseudorandom codes, already discussed in their previous work. This article presents a detailed analysis of errors in CW FM sonar with pseudo-random sequence code modulation...
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Aggregated conducted interferences generated by group of asynchronous drives with deterministic and random modulation
PublikacjaThis paper addresses problems linked with electromagnetic interferences generated by group of three adjustable speed drives fed by frequency converters with deterministic and random modulation. Based on the experimental results it has been shown that decreasing of the conducted interferences in a case of random modulation is measuring phenomenon linked with selectivity of the EMI receiver.
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Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublikacjaThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
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Detection of the Direct Sequence Spread Spectrum Signals with BPSK Modulation
PublikacjaThis paper presents a method of the DS CDMA signals with BPSK modulation detection through the examination of the enhanced signal spectrum density. On the base of experiments carried out on the real radio communication signals the impact of a narrowband emission occurring in the examined frequency band on the detection process effectiveness was shown. The results of the experiment aimed at the detection of the satellite navigation...
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Pulse-Width Modulation of Power Electronic DC–AC Converter
PublikacjaThe Second Edition of High Performance Control of AC Drives with Matlab®/Simulink delivers an updated and thorough overview of topics central to the understanding of AC motor drive systems. The book includes new material on medium voltage drives, covering state-of-the-art technologies and challenges in the industrial drive system, as well as their components, and control, current source inverter-based drives, PWM techniques for...
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A recursive multi-output dicrete-time sinusoidal oscillator
PublikacjaZaproponowano wielo-wyjściowy cyfrowy oscylator sinusoidalny. Przedstawiono performancję tego oscylatora. Oscylator generuje sinusoidy: o zadanych fazach początkowych i o jednostkowej amplitudzie, przy użyciu algorytmów rekursywnych. Wprowadzona tu macierz rotacji zespolonego oscylatora unifikuje różne struktury zespolonych oscylatorów i pozwala na wprowadzenie nowych struktur trójfazowych, cztero-fazowych i ogólnie wielo-fazowych...
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Double-ridged horn antenna with sinusoidal ridge profile
PublikacjaPrzedstawiono wyniki symulacji numerycznej oraz pomiarów parametrów anteny tubowej z podwójnym grzbietem. Badania numeryczne dotyczyły zarówno samego układu zasilania falowodu grzbietowego jak i całej anteny z uwzględnieniem sinusoidalnego profilu impedancji grzbietu. Wyniki obliczeń dopasowania oraz charakterystyk promieniowania, wykonanych przy użyciu symulatora QW-3D, porównano z wynikami pomiarów, stwierdzając dobrą zgodność...
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Investigation of the temperature modulation parameters on semiconductor gas sensor response
PublikacjaIn this work we present the results of the investigation of the sensing properties of semiconductor gas sensors with a sinusoidally modulated temperature in the presence of synthetic air (SA) and three volatile air pollutants, i.e. NH3, NO2 and SO2. The measurements were performed for different average sensor heater temperatures and the amplitude of the modulation signal. In addition, the extraction of features from the sensor...
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Direct modulation for conventional matrix converters using analytical signals and barycentric coordinates
PublikacjaThis paper proposes the generalized direct modulation for Conventional Matrix Converters (CMC) using the concept of analytical signals and barycentric coordinates. The paper proposes a novel approach to the Pulse Width Modulation (PWM) duty cycle computing, which allows faster prototyping of direct control algorithms. The explanation of the new idea using analytical considerations demonstrating the principles of direct voltage...
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Sinusoidal Control of a Brushless DC Motor with Misalignment of Hall Sensors
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Effect of Sinusoidal Corrugated Geometries on the Vibrational Response of Viscoelastic Nanoplates
PublikacjaThe vibrational behavior of viscoelastic nanoplates with a corrugated geometry is a key topic of practical interest. This problem is addressed here for wrinkled nanoplates with small corrugations related to incorrect manufacturing. To this end, a new One-Variable First-order Shear Deformation plate Theory (OVFSDT) is proposed in a combined form with a non-local strain gradient theory. The Kelvin–Voigt model is employed to describe...
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Time-current tripping characteristics of RCDs for sinusoidal testing current
PublikacjaLow-voltage electrical installations are verified initially – before being put into operation, as well as periodically – during their utilization. According to the IEC standards, the scope of the verification includes measurements of both the tripping current and the disconnection time of residual current devices (RCDs). Experiences in RCDs testing show that disconnection times of two or more similar RCDs can be quite different....
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A Direct Modulation for Matrix Converters based on the Onecycle Atomic operation developed in Verilog HDL.
PublikacjaThis paper presents a fast direct Pulse Width Modulation (PWM) algorithm for the Conventional Matrix Converters (CMC) developed in Verilog Hardware Description language (HDL). All PWM duty cycle calculations are performed in one cycle by an atomic operation designed as a digital module using FPGA basic blocks. The algorithm can be extended to any number of output phase. The improved version of the discontinuous Direct Analytic...
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Contr-rotating eccentric-mass rotors used as exciters of sinusoidal forces applied to elastically supported bodies
PublikacjaThe work focuses on aspects of multibody dynamics. Investigated object is a mass driven by rotations of an inertial shaker. Resulting vibrational set consists of two counter-rotating identically-unbalanced rotors. Since the mass centres of the rotors do not coincide with the axes of their rotations, significant centrifugal forces arise during rotations. As both rotors are identically unbalanced, the inter-axial force components...
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Analog fault signature based on sigma-delta modulation and oscillation-test methodology.
PublikacjaW artykule dokonano przeglądu prac z zakresu testowania układów elektronicznych metodą oscylacyjną. Wskazując na niedostatki aktualnie stosowanej techniki testowania oscylacyjnego zaproponowano nową sygnaturę uszkodzeń dla układów analogowych. Proponowany parametr diagnostyczny jest wydobywany z odpowiedzi czasowej oscylatora testującego, w układzie złożonym z detektora szczytowego, modulatora sigma-delta oraz licznika rewersyjnego....
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Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
PublikacjaA CW FM type sounding signal is used in the classical solution of silent sonar. While the signal provides a relatively simple implementation of digital signal processing, and ensures good detection conditions, unfortunately, in the presence of the Doppler effect, distance measurement results tend to be wrong. This is due to the fact that the received signal’s instantaneous frequency value is dependent both on the distance to the...
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Accidental wow evaluation based on sinusoidal modeling and neural nets prediction
PublikacjaReferat przedstawia opis algorytmu do określenia charakterystyki zniekształcenia kołysania dźwięku. Prezentowane podejście wykorzystuje sinusoidalną analizę dźwięku bazującą zarówno na amplitudowym jak i fazowym widmie sygnału fonicznego. Trajektorie poszczególnych składowych tonalnych, obrazujące zniekształcenie kołysania, określane są na podstawie analizy ich chwilowych amplitud, częstotliwości i faz. Dodatkowo referat przedstawia...
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Multi-channel radio-over-fiber communication systems through modulation instability phenomenon
PublikacjaRecent advancements in Radio-over-Fiber (RoF) technology have positioned it as a promising solution for highcapacity wireless communications. This paper explores novel applications of RoF systems in enhancing phased array antenna (PAA) performance for multi-channel wireless communication applications through the modulation instability (MI) phenomenon. Utilizing fibers experiencing MI with varying group velocity dispersions (β2)...
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Performance of underwater data transmission using incoherent modulation MFSK in very shallow waters
PublikacjaEnsuring universal and stable underwater communication in shallow waters for various environmental conditions is a difficult scientific and engineering task. In particular, this applies to underwater communication systems that use acoustic waves in very shallow underwater channels, where multipath propagation permanently occurs. The article provides assumptions for a system working with incoherent M-ary Frequency Shift Keying (MFSK)...
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Virtual Space Vector Pulse Width Modulation Algorithm for Three-Level NPC Converters Based on the Final Element Shape Functions
PublikacjaThe paper puts forth a novel idea for the computation of Nearest Three Virtual Space Vector Pulse Width Modulation for the three level NPC converters. The computations are based on the concept of final element shape function widely used in the domain of finite element analysis. The proposed approach significantly frees the computations from the use of trigonometric functions, which simplifies the computations and permits easier...
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The Conceptual Research over Low-Switching Modulation Strategy for Matrix Converters with the Coupled Reactors
PublikacjaIn this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual analysis and later validated by simulation. The paper shows how the combination of CMCs and CRs could be of special interest...