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Tytuł:
Zastosowanie filtrów wygładzających do estymacji współczynnika SNR w sygnałach zakłóconych szumem o rozkładzie normalnym
Application smoothing filters to estimate the SNR in the noise signals disturbed of the normal distribution
Autorzy:
Mikołajczak, G.
Pęksiński, J.
Kowalski, J.
Powiązania:
https://bibliotekanauki.pl/articles/377657.pdf
Data publikacji:
2016
Wydawca:
Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Tematy:
filtry wygładzające
SNR
Opis:
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.
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.
Źródło:
Poznan University of Technology Academic Journals. Electrical Engineering; 2016, 88; 101-108
1897-0737
Pojawia się w:
Poznan University of Technology Academic Journals. Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Subcarrier Gain Based Power Allocation in Multicarrier Systems
Autorzy:
Abd-Elnaby, M.
Sedhom, G. G.
Messiha, N. W.
Abd El-Samie, F. E.
Zhu, X.
Powiązania:
https://bibliotekanauki.pl/articles/958110.pdf
Data publikacji:
2014
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
GPA
OFDM
QAM
SNR
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2014, 1; 62-67
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PC-based high frequency imaging system with coded excitation
Autorzy:
Lewandowski, M.
Nowicki, A.
Powiązania:
https://bibliotekanauki.pl/articles/331588.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
coded transmission
SNR
FPGA
Opis:
Coded transmission is a technique that gives significant improvement in SNR and enables higher contrast imaging without sacrificing the resolution. A novel HF (20-35 MHz) ultrasound real-time imaging system for research and evaluation of the coded transmission was developed. The digital programmable coder-digitizer module based on the field programmable gate array (FPGA) chip supports arbitrary waveform coded transmission and RF echoes sampling up to 200 MSPS. A novel balanced software architecture supports real-time RF processing and display at rates up to 30 frames/sec. The system was used to gather data for sine burst and 16-bit Golay code excitation using a single element scanning head with thick film focused spherical transducer 25 MHz center frequency and 56% system bandwidth. SNR gain for the Golay codes (referenced to single burst) of 15 dB for 20 MHz and 16 dB for 35 MHz were obtained. In water the axial resolution for both single burst and the Golay codes was the same FWMH=20 ns at 20 MHz and FWMH=15 ns at 35 MHz. The presented system is a practical and low cost implementation of coded excitation technique in HF ultrasound imaging.
Źródło:
Hydroacoustics; 2008, 11; 239-247
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Link Quality and Energy Aware Geographical Routing in MANETs using Fuzzy Logics
Autorzy:
Mishra, P.
Gandhi, C.
Singh, B.
Powiązania:
https://bibliotekanauki.pl/articles/308336.pdf
Data publikacji:
2016
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
GPSR
LAR
MANET
RSSI
SINR
SNR
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2016, 3; 5-17
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studying and Modeling the Performance of the TCM-STBC Systems in the Rayleigh Channel
Autorzy:
Bendelhoum, Mohammed Sofiane
Lahcene, Mohamed Rida
Menezla, Fayssal
Elarbi, Abderraouf
Powiązania:
https://bibliotekanauki.pl/articles/1839476.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
BER
MIMO
SNR
STBC
STTC
TCM
TCM-STBC
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 1; 1-7
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A model of OFDM based maritime VHF communication system for data exchange
Autorzy:
Valčić, S.
Pogány, T.
Mrak, Z.
Powiązania:
https://bibliotekanauki.pl/articles/260386.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
maritime VHF communications
OFDM modulation
AWGN
SNR
BER
Opis:
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.
Źródło:
Polish Maritime Research; 2018, 2; 27-36
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hardware Implementation of MISO on Orthogonal Frequency Division Multiplexing Platform with the Help of Alamouti Algorithm
Autorzy:
Kilaru, S.
Powiązania:
https://bibliotekanauki.pl/articles/226220.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
MISO
SISO
FPGA
Xilinx
BER
SNR
Alamouti
LTE
Opis:
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.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 2; 137-143
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studying and Modeling the Performance of the TCM-STBC Systems in the Rayleigh Channel
Autorzy:
Bendelhoum, Mohammed Sofiane
Lahcene, Mohamed Rida
Menezla, Fayssal
Elarbi, Abderraouf
Powiązania:
https://bibliotekanauki.pl/articles/1839490.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
BER
MIMO
SNR
STBC
STTC
TCM
TCM-STBC
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 1; 1-7
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Improved Downlink MC-CDMA System for Effcient Image Transmission
Autorzy:
Bendelhoum, M. S.
Djebbari, A.
Boukli-Hacene, I.
Taleb-Ahmed, A.
Powiązania:
https://bibliotekanauki.pl/articles/308187.pdf
Data publikacji:
2017
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
data compression
MC-CDMA
MSSIM
performance evaluation
PSNR
SNR
SPIHT
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2017, 4; 5-16
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Periodic signal detection with using duffing system poincare map analysis
Autorzy:
Martynyuk, V
Fedula, M
Balov, O
Powiązania:
https://bibliotekanauki.pl/articles/102192.pdf
Data publikacji:
2014
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
periodic signal detection
chaotic system
Duffing oscillator
Poincare sections
SNR
Opis:
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.
Źródło:
Advances in Science and Technology. Research Journal; 2014, 8, 22; 26-30
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Investigation of the MIMO Space Time Block Code Based Selective Decode and Forward Relaying Network over η–µ Fading Channel Conditions
Autorzy:
Shankar, Ravi
Raman, V. V. Raghava
Rane, Kantilal Pitamber
Sarojini, B. K.
Neware, Rahul
Powiązania:
https://bibliotekanauki.pl/articles/2058506.pdf
Data publikacji:
2022
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
5G
MIMO
MRC
non-homogeneous fading channel
PEP
S-DF
SNR
Opis:
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.
Źródło:
Journal of Telecommunications and Information Technology; 2022, 1; 79--92
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effectiveness of the spatial acceleration modulus for rolling elements bearing fault detection
Autorzy:
Cotogno, M.
Cocconcelli, M.
Rubini, R.
Powiązania:
https://bibliotekanauki.pl/articles/329466.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
rolling element bearing
diagnostic
spatial acceleration modulus
SAM
SNR
spectral Kurtosis
envelope analysis
Opis:
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.
Źródło:
Diagnostyka; 2013, 14, 4; 27-34
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multipath detection with the combination of SNR measurements – Example from urban environment
Autorzy:
Špánik, P.
Hefty, J.
Powiązania:
https://bibliotekanauki.pl/articles/145370.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
satelita nawigacyjny
fala radiowa
pomiar szumu
multipath
detection
SNR
three-frequency combination
GNSS positioning
Opis:
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.
Źródło:
Geodesy and Cartography; 2017, 66, 2; 305-315
2080-6736
2300-2581
Pojawia się w:
Geodesy and Cartography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wykorzystanie zmodernizowanej aparatury oblotu technicznego zainstalowanej na samolocie SONEX LL do oblotu stacji naprowadzania rakiet systemu NEWA
Use of modernized flight test equipment onboard of SONEX LL aircraft to fly the Newa Missile Guidance System
Autorzy:
Karczmarz, Dariusz
Mądrzycki, Przemysław
Szkudlarz, Henryk
Grzywiński, Stanisław
Podciechowski, Maciej
Żygadło, Stanisław
Powiązania:
https://bibliotekanauki.pl/articles/38943397.pdf
Data publikacji:
2023
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
aparatura
oblot techniczny
stacja naprowadzania rakiet
kontrola parametrów technicznych
SNR
technical flight
equipment
missile guidance station
control of technical parameters
Opis:
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.
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.
Źródło:
Journal of KONBiN; 2023, 53, 4; 61-78
1895-8281
2083-4608
Pojawia się w:
Journal of KONBiN
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ANSDM converters dynamic range design process
Autorzy:
Golański, Ryszard
Godek, Juliusz
Powiązania:
https://bibliotekanauki.pl/articles/1402376.pdf
Data publikacji:
2020
Wydawca:
Państwowa Wyższa Szkoła Zawodowa w Tarnowie
Tematy:
delta modulation
non-uniform sampling
SNR
dynamic range
Lambert W function
sampling interval
Maple
modulacja delta
nierównomierne próbkowanie
zakres dynamiczny
funkcja Lamberta
odstęp próbkowania
Opis:
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.
Źródło:
Science, Technology and Innovation; 2020, 10, 3; 1-7
2544-9125
Pojawia się w:
Science, Technology and Innovation
Dostawca treści:
Biblioteka Nauki
Artykuł

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