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1

Reliable 5G waveform detection from an optical fibre transmitter system

Yaseen Zeyad T., Algriree Waleed

Opto-Electronics Review

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2024

|

Vol. 32, No. 1

art. no. e149181

EN

The integration of optical fibre communication with multiple input multiple output-non-orthogonal multiple access (MIMO-NOMA) waveforms in cognitive radio (CR) systems is examined in this study. The proposed system leverages the advantages of optical fibre, including high bandwidth and immunity to electromagnetic interference to facilitate the transmission and reception of MIMO-NOMA signals in a CR environment. Moreover, MIMO-NOMA signal was detected and analysed by the hybrid-discrete cosine transform-Welch (H-DCT-W) method. Based on the modes results, a detection probability greater than 0.96%, a false alarm probability equal to 0.06, and a global system error probability equal to 0.09% were obtained with a signal-to-noise ratio (SNR) less than 0 dB, while maintaining a simple level of complexity. The results obtained in this paper indicate the potential of the optical fibre-based MIMO-NOMA system based on H-DCT-W technology in CR networks. Therefore, its suitability for practical CR applications is demonstrated by the improvements obtained in false alarms, detection probability, and error rates at low levels of SNR. This study contributes to the development of efficient and reliable wireless communication systems by linking cooperation and synergy concerning MIMO-NOMA, optical fibres, as well as the proposed detection technique (H-DCT-W).

2

Measurement of High-Frequency Sub-Noise Temperature Signal and RMS Current Using a Single-Detector High-Speed IR System

Torzyk Błażej, Więcek Bogusław

Pomiary Automatyka Robotyka

|

2023

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R. 27, nr 4

53--56

EN

NETD (Noise Equivalent Temperature Difference) parameter of infrared systems is the important parameter that allows determining the limit of temperature measurement of tested objects. Currently, the commercially available devices have the NETD < 20 mK. The infrared (IR) detectors and accompanying electronic circuits generate noise. In consequence, it is difficult to achieve the high level of signal-to-noise ratio (SNR) while measuring temperature. This paper presents a method of measuring the root mean square (RMS) value of alternating current, using a single-detector high-speed IR system for detecting 100 Hz harmonic spectral component of temperature, whose value is certainly below NETD limit.

PL

Parametr NETD (ang. Noise Equivalent Temperatura Difference) dla systemów podczerwieni (IR) jest ważnym parametrem pozwalającym określić dolną granicę pomiaru temperatury badanych obiektów. Obecnie dostępne na rynku chłodzone kamery termowizyjne charakteryzuje parametr NETD < 20 mK. Detektory podczerwieni i towarzyszące im obwody elektroniczne generują szum. W konsekwencji trudno jest uzyskać wysoki poziom stosunku sygnału do szumu (SNR) w systemach radiacyjnego pomiaru temperatury. W artykule przedstawiono metodę pomiaru wartości skutecznej prądu przemiennego stosując system IR z pojedynczym detektorem o dużej częstotliwości generacji próbek. Metoda polega na pomiarze składowej harmonicznej widma temperatury o częstotliwości 100 Hz, której wartość jest znacznie mniejsza od poziomu określonego przez parametr NETD.

3

Wykorzystanie zmodernizowanej aparatury oblotu technicznego zainstalowanej na samolocie Sonex LL do oblotu stacji naprowadzania rakiet systemu NEWA

Karczmarz Dariusz, Mądrzycki Przemysław, Szkudlarz Henryk, Grzywiński Stanisław, Podciechowski Maciej, Żygadło Stanisław

Journal of KONBiN

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2023

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Vol. 53, iss. 4

61--78

PL

W artykule omówiono modernizację aparatury do przeprowadzania oblotów technicznych Przeciwlotniczego Zestawu Rakietowego NEWA SC (SA-3 Goa – kod NATO) polegającą na zastąpieniu samolotu TS-11 Iskra samolotem SONEX LL oraz przystoso-waniu zestawu aparatury oblotowej montowanej dotychczas na TS-11 Iskra do nowego samolotu-nosiciela. Przeprowadzono badania porównawcze w warunkach poligonowych, które potwierdziły poprawność przyjętych rozwiązań technicznych.

EN

The article discusses the modernization of the Anti-Aircraft Missile System NEWA SC (SA-3 Goa – NATO code) flight test equipment, consisting in replacing the TS-11 Iskra aircraft with the SONEX LL aircraft and adapting the set of flight test equipment previously mounted on the TS-11 Iskra to the new carrier aircraft. Comparative tests were carried out in field conditions, which confirmed the correctness of the adopted technical solutions.

4

An Investigation of the MIMO Space Time Block Code Based Selective Decode and Forward Relaying Network over η–µ Fading Channel Conditions

Shankar Ravi, Raman V. V. Raghava, Rane Kantilal Pitamber, Sarojini B. K., Neware Rahul

Journal of Telecommunications and Information Technology

|

2022

|

nr 1

79--92

EN

In this paper, we examine the end-to-end average pairwise error probability (PEP) and output probability (OP) performance of the maximum ratio combining (MRC) based selective decode and forward (S-DF) system over an η–µ scattering environment considering additive white Gaussian noise (AWGN). The probability distribution function (PDF) and cumulative distribution function (CDF) expressions have been derived for the received signal-to-noise (SNR) ratio and the moment generating function (MGF) technique is used to derive the novel closed-form (CF) average PEP and OP expressions. The analytical results have been further simplified and are presented in terms of the Lauricella function for coherent complex modulation schemes. The asymptotic PEP expressions are also derived in terms of the Lauricella function, and a convex optimization (CO) framework has been developed for obtaining optimal power allocation (OPA) factors. Through simulations, it is also proven that, depending on the number of multi-path clusters and the modulation scheme used, the optimized power allocation system was essentially independent of the power relation scattered waves from the source node (SN) to the destination node (DN). The graphs show that asymptotic and accurate formulations are closely matched for moderate and high SNR regimes. PEP performance significantly improves with an increase in the value of η for a fixed value of µ. The analytical and simulation curves are in close agreement for medium-to-high SNR values.

5

Studying and Modeling the Performance of the TCM-STBC Systems in the Rayleigh Channel

Bendelhoum Mohammed Sofiane, Lahcene Mohamed Rida, Menezla Fayssal, Elarbi Abderraouf

Journal of Telecommunications and Information Technology

|

2021

|

nr 1

1--7

EN

Multiple-input multiple-output (MIMO) systems will play an important role in future generations of wireless networks. Space-time block code (STBC) and space-time trellis code (STTC) are two techniques that may be used in multi-antenna radio systems. This paper aims, most importantly, to study the performance of STBC systems at different values of such parameters as spectral efficiency, matrix codes and constellations. A performance comparison between STBC and STTC schemes is performed. In order to show the efficiency of the system’s ability to communicate with uncoded and coded transmission structures over AWGN and Rayleigh channels, the trellis-coded modulation (TCM) is introduced. The results obtained show that the proposed TCM-STBC system model, using one and two receiving antennas, improves the performance of Rayleigh channel communication systems at 9.5 dB and 11.5 dB for a BER of 10−5.

6

ANSDM converters dynamic range design process

Golański Ryszard, Godek Juliusz

Science, Technology and Innovation

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2020

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Vol. 10, no. 3

1--7

EN

The results of analytic and simulating works proved that for nonstationary sources, the delta converters with adaptive sampling expose higher coding efficiency than the former proposals, based on uniform sampling methods. The knowledge of the sampling interval range and the algorithm of the Nonuniform Sampling Delta Modulation and Adaptive Nonuniform Sampling Delta Modulation allows finding the necessary number of the sampling intervals and their values that maximizes SNR. The total dynamic range of the ANSDM modulator is the product of the dynamic range both from sampling interval and step size adaptation. Due to the high complexity of the calculations, the ANSDMsoft program was developed to support computing. All computational works were carried out using the Maple environment. Maple allows to solve complex mathematical functions and display their results in a simple way. Most importantly, it supports the LambertW function, used in the computing of NSDM or ANSDM modulators parameters. Graphic illustrations of the NSDM and ANSDM modulator dynamic range as a function of the minimum and maximum sampling frequency are presented.

7

A migration based location method using improved waveform stacking for microseismic events in a borehole system

Mao Qinghui, Azeem Tahir, Zhang Xuliang, Zhong Yu, Fang Yuan, Zhang Yunxiao

Acta Geophysica

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2020

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Vol. 68, no. 6

1609--1618

EN

The migration-based microseismic event location methods using waveform stacking algorithms are widely used for hydrofracturing monitoring. These methods have the advantage of not requiring the accurate frst arrival time around a detected event, which is more suitable for noisy data than classical travel time-based methods. However, accuracy of these methods can be afected under the condition of relatively low signal-to-noise ratio (SNR). Therefore, in order to enhance the location accuracy of microseismic events in a borehole system, we have proposed a migration-based location method using improved waveform stacking with polarity correction based on a master-event technique, which optimizes the combination way of P- and S-wave waveform stacking. This method can enhance the convergence of the objective function and the location accuracy for microseismic events as compared to the conventional waveform stacking. The proposed method has been successfully tested by using synthetic data example and feld data recorded from one downhole monitoring well. Our study clearly indicates that the presented method is more viable and stable under low SNR.

8

Optical fiber marine seismic exploration system feasibility study

Wang Xiangchun, Li Xueliang, Zhang Haibing, Hao Xiaozhu, Yu Kaiben

Acta Geophysica

|

2019

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Vol. 67, no. 5

1403--1411

EN

The signal-to-noise ratio (SNR), vertical resolution and fdelity of marine seismic data are closely related to the characteristics of hydrophones, namely the sensitivity and the frequency band range. In this article, we analyzed and processed seismic data collected in 2017 from a towed marine streamer equipped with optical fiber cable and hydrophones. Results from a pre-stack time migration section revealed that the optical fiber seismic data yielded high SNR, vertical resolution and fdelity. For validation purpose, a comparison of these data with those acquired by classic piezoelectric hydrophones along a migration section located in a very close location was carried out. This comparison showed that the SNR, fdelity and vertical resolution from the two means of measurements were comparable.

9

A model of OFDM based maritime VHF communication system for data exchange

Valčić S., Pogány T., Mrak Z.

Polish Maritime Research

|

2018

|

nr 2

27--36

EN

In the maritime Very High Frequency (VHF) band, there are no systems for transmitting large amounts of data. Therefore, it is necessary to develop new systems that would modernize the Global Maritime Distress and Safety System (GMDSS), significantly relieve the Automatic Identification System’s (AIS) communication channels, and set guidelines for the development of communication infrastructure of the e-Navigation. In line with this, analytical and simulation models of the maritime VHF data transmission communication system using Orthogonal Frequency Division Multiplexing (OFDM) modulation are worked out in this paper. The achieved data rate, the spectral efficiency and the bit error rate (BER) represent validation parameters on which the results of the analytical and simulation models are evaluated. It is concluded that the application of the digital OFDM modulation in the maritime VHF band may improve the GMDSS system by achieving higher data rates compared to the current terrestrial mandatory systems for data exchange, i.e. Digital Selective Calling (DSC) and AIS.

10

An Improved Downlink MC-CDMA System for Effcient Image Transmission

Bendelhoum M. S., Djebbari A., Boukli-Hacene I., Taleb-Ahmed A.

Journal of Telecommunications and Information Technology

|

2017

|

nr 4

5--16

EN

Image compression is an essential stage of the data archiving and transmitting process, as it reduces the number of bits and the time required to complete the transmission. In this article, a study of image transmission over the Multi-Carrier Code Division Multiple Access (MC-CDMA) downlink system is presented. The solution proposed relies on source coding combined with channel coding. The Discrete Wavelet Transform (DWT) method is used in conjunction with the SPIHT coder to compress the image, then the data generated is transmitted with the MC-CDMA technique over a noisy channel. The results show that image transmissions performed over MC-CDMA using the SPIHT model are better than the traditional approach like MC-CDMA in the AWGN channel.

11

Hardware Implementation of MISO on Orthogonal Frequency Division Multiplexing Platform with the Help of Alamouti Algorithm

Kilaru S.

International Journal of Electronics and Telecommunications

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2017

|

Vol. 63, No. 2

137--143

EN

Many software based OFDM techniques were proposed from last half decade to improve the performance of the system. This paper tried to implement the same with Hardwar implementation. We created Hardware based MISO platform with OFDM. We implemented Alamouti algorithm on this test bed. The test bed is implemented with the help of Field Programmable Gate Array (FPGA). The test bed is functionalized with the help of FPGA through Xilinx based system generator for DSP. In this paper we considered the 2×1 MISO implementation with Alamouti algorithm. The simulation results showed that BER and SNR are considerably high for MISO than SISO. The results also proved that proposed OFDM based Alamouti implementation for MISO is excellent in all performance criterions.

12

Multipath detection with the combination of SNR measurements – Example from urban environment

Špánik P., Hefty J.

Geodesy and Cartography

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2017

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Vol. 66, no. 2

305--315

EN

Multipath is one of the most severe station-dependent error sources in both static and kinematic positioning. Relatively new and simple detection technique using the Signal-to-Noise (SNR) measurements on three frequencies will be presented based on idea of Strode and Groves. Exploitation of SNR measurements is benefi cial especially for their unambiguous character. Method is based on the fact that SNR values are closely linked with estimation of pseudo-ranges and phase measurements during signal correlation processing. Due to this connection, combination of SNR values can be used to detect anomalous behavior in received signal, however some kind of calibration in low multipath environment has to be done previously. In case of multipath, phase measurements on different frequencies will not be affected in the same manner. Specular multipath, e.g. from building wall introduces additional path delay which is interpreted differently on each of the used carrier, due to different wavelengths. Experimental results of multipath detection in urban environment will be presented. Originally proposed method is designed to work with three different frequencies in each epoch, thus only utilization of GPS Block II-F and Galileo satellites is possible. Simplification of detection statistics to use only two frequencies is made and results using GPS and GLONASS systems are presented along with results obtained using original formula.

13

Zastosowanie filtrów wygładzających do estymacji współczynnika SNR w sygnałach zakłóconych szumem o rozkładzie normalnym

Mikołajczak G., Pęksiński J., Kowalski J.

Poznan University of Technology Academic Journals. Electrical Engineering

|

2016

|

No. 88

101--108

PL

W pracy przedstawiono metodę estymacji współczynnika SNR opartą o wybrane metody wygładzania sygnałów przy założeniu, że w procesie filtracji tłumiony jest tylko szum. Znajomość współczynnika redukcji szumu pozwala wyznaczyć wartość estymowanej wielkości. Obliczenia i symulacje wykonano dla sygnału harmonicznego zakłóconego szumem o rozkładzie normalnym.

EN

The paper presents a method of estimating the SNR based on the selected method of smoothing signals on the assumption that the filtration process is suppressed only noise. Knowledge of Noise Reduction Coefficient lets you determine the value of the estimated size. Calculations and simulations were performed in the harmonic signal noise disturbed the normal distribution.

14

Link Quality and Energy Aware Geographical Routing in MANETs using Fuzzy Logics

Mishra P., Gandhi C., Singh B.

Journal of Telecommunications and Information Technology

|

2016

|

nr 3

5--17

EN

In literature, varieties of topology and geographical routing protocols have been proposed for routing in the MANETs. It is widely accepted that the geographical routings are a superior decision than topological routings. Majority of geographical routing protocols assume an ideal network model and choose the route that contains minimum number of hops. However, in reality, nodes have limited battery power and wireless links are additionally unreliable, so they may highly affect the routing procedure. Thus, for reliable data transmission, condition of the network such as link quality and residual energy must be considered. This paper aims to propose a novel multi-metric geographical routing protocol that considers both links-quality and energy metric along with progress metric to choose the next optimal node. The progress is determined by utilizing greedy as well as compass routing rather than pure greedy routing schemes. To combine these metrics, fuzzy logics are used to get the optimal result. Further, the protocol deals with “hole” problem and proposes a technique to overcome it. Simulations show that the proposed scheme performs better in terms of the packet delivery ratio, throughput and residual energy than other existing protocols.

15

Kontrola jakości systemów MRI : testy podstawowe

Sokół M., Wicher M., Wochlik I., Bułka J., Machnikowska-Sokołowska M.

Inżynier i Fizyk Medyczny

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2016

|

Vol. 5, nr 6

301--308

PL

Rezonans magnetyczny, od momentu zaistnienia, zajął centralne miejsce wśród technik radiologicznych. O ile jednak w przypadku aparatury rentgenodiagnostycznej obowiązują w zakresie kontroli jakości jednolite zalecenia i przepisy prawne, to nie ma takich wytycznych w odniesieniu do MRI. Procedury kontroli jakości opracowane przez ACR (American College of Radiology) mogą stanowić idealny punkt wyjścia do konstruowania własnego programu kontroli jakości w pracowni MRI. W niniejszej pracy opisano osiem podstawowych testów systemu MRI, takich jak: kontrola współczynnika stosunku sygnału do szumu, częstotliwości rezonansowej, zniekształceń geometrycznych, jednolitości intensywności obrazu, obecności cieni dodatkowych na obrazach, rozdzielczości przestrzennej przy wysokim kontraście, wykrywania obiektów o niskim kontraście, grubości warstwy i położenia warstwy. Testy wykonano przy użyciu fantomu ACR MRI oraz w kilku przypadkach, dla porównania, fantomu GE.

EN

Since its discovery, magnetic resonance imaging (MRI) has been one of the main methods of imaging in radiology. So far, there are not many national or international guidelines for MRI quality assurance (QA) compared to imaging methods that are using ionizing radiation. Thus, the QA procedures developed by the American College of Radiology (ACR) may constitute an ideal starting point for constructing an own MRI QA program. In this study, eight basic test procedures, such as: signal-to-noise ratio, central frequency of the scanner, geometric accuracy, image intensity uniformity, percent signal ghosting, high-contrast resolution, low-contrast object detectability, slice thickness accuracy and slice position accuracy are described. The tests were done using the ACR MRI phantom, however in some of the tests also the GE phantomwas applied, for a sake of comparison.

16

Effects of various typical electrodes and electrode gels combinations on MRI signal-to-noise ratio and safety issues in EEG-fMRI recording

Gao D., Li M., Li J., Liu Z., Yao D., Li G., Liu T.

Biocybernetics and Biomedical Engineering

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2016

|

Vol. 36, no. 1

9--18

EN

To compare the effects of typical Ag/AgCl electrodes and electrode gels on MR images and assess safety hazards for patients during the electroencephalogram (EEG) data simultaneously with functional MRI (fMRI) recordings. So the measurements were conducted to compare the effects of three electrodes, three electrode gels and their combinations on the signal-to-noise ratio (SNR) of MR images at 3 T. Local temperature variation of the phantom for all conditions was also measured in the scanner. Results show that combination of silver-plated copper electrode and electrode gel (composed of carbomer as its main ingredient, with 85% moisture) is best for EEG-fMRI experiments. A sintered Ag/AgCl electrode could also be used as the material of EEG cap if infra-slow EEG-events need to be acquired in EEG-fMRI recording. Additionally, there is no significant heat induction detected. Overall, the methods and results of this study can be used for selecting appropriate EEG electrodes and electrode gels in EEG-fMRI experiments.

17

Adaptive ECG signal denoising approach in the initial signal processing stage of electrocardiograph system

Irzmański P., Jóśko A., Figoń P.

Przegląd Elektrotechniczny

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2015

|

R. 91, nr 7

8-10

EN

The research presents a concept/laboratory model of the proposed approach to ECG signal denoising. An adaptive module is designed for the pre-processing ECG signal enhancement and noise rejection. The research aims at the proposal of the processing method for removing these distortions with relatively low computational complexity.

PL

Autorzy prezentują model laboratoryjny podejścia do automatycznego oczyszczania sygnałów EKG. Struktura ta skonstruowana jest w postaci zestawu elementów realizujących przy relatywnie niskiej złożoności obliczeniowej ocenę poziomu szumu, dobierając tym samym w sposób płynny odpowiedni zestaw współczynników filtrów.

18

Subcarrier Gain Based Power Allocation in Multicarrier Systems

Abd-Elnaby M., Sedhom G. G., Messiha N. W., Abd El-Samie F. E., Zhu X.

Journal of Telecommunications and Information Technology

|

2014

|

nr 1

62--67

EN

The Orthogonal Frequency Division Multiplexing (OFDM) transmission is the optimum version of the multicarrier transmission scheme, which has the capability to achieve high data rate. The key issue of OFDMsystem is the allocation of bits and power over a number of subcarriers. In this paper, a new power allocation algorithm based on subcarrier gain is proposed to maximize the bit rate. For OFDM systems, the Subcarrier Gain Based Power Allocation (SGPA) algorithm is addressed and compared with the standard Greedy Power Allocation (GPA). The authors demonstrate by analysis and simulation that the proposed algorithm reduces the computational complexity and achieves a near optimal performance in maximizing the bit rate over a number of subcarrier.

19

Periodic signal detection with using duffing system poincare map analysis

Martynyuk V, Fedula M, Balov O

Advances in Science and Technology. Research Journal

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2014

|

Vol. 8, nr 22

26--30

EN

In this article the periodic signal detection method on the base of Duffing system chaotic oscillations analysis is presented. This work is a development of the chaos-based signal detection technique. Generally, chaos-based signal detection is the detection of chaotic-to-periodic state transition under input periodic component influence. If the in¬put periodic component reaches certain threshold value, the system transforms from chaotic state to periodic state. The Duffing-type chaotic systems are often used for such a signal detection purpose because of their ability to work in chaotic state for a long time and relatively simple realization. The main advantage of chaos-based signal detection methods is the utilization of chaotic system sensitivity to weak signals. But such methods are not used in practice because of the chaotic system state control problems. The method presented does not require an exact system state control. The Duffing system works continuously in chaotic state and the periodic signal detection process is based on the analysis of Duffing system Poincare map fractal structure. This structure does not depend on noise, and therefore the minimum input signal-to-noise ratio required for periodic signal detection is not limited by chaotic system state control tolerance.

20

Effectiveness of the spatial acceleration modulus for rolling elements bearing fault detection

Cotogno M., Cocconcelli M., Rubini R.

Diagnostyka

|

2013

|

Vol. 14, No. 4

27--34

EN

Rolling Elements Bearing (REB) condition monitoring is mainly based on the analysis of acceleration (vibration) signal in the load direction. This is one of the three components of the acceleration vector in 3D space: the main idea of this paper is the recovery of additional fault information from the other two acceleration vector components by combining them to obtain the modulus of the spatial acceleration (SAM) vector. The REB diagnostic performances of the SAM are investigated and compared to the load direction of vibration by means a rough estimator of the “Signal-to-Noise” Ratio and the Spectral Kurtosis. The SAM provides a higher SNR than the single load direction. Finally, Spectral Kurtosis driven Envelope analysis is performed for further comparison of the two signals: its results highlight that demodulation of the SAM isn’t stricly necessary to extract the fault features, which are already available in the raw signal spectrum.