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Wyszukujesz frazę "Salamon, R." wg kryterium: Autor


Tytuł:
A directional sonobuoy system for submarine detection
Autorzy:
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332131.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
This article outlines the methods of detecting and locating submarines. Special attention is paid to the airborne system utilizing directional sonobuoys. The article discusses operating principles of such systems, a method of detecting and estimating the approach direction of the acoustic wave emitted by the vessel, and practical visualization methods. The article is related to the successful development of a Polish prototype of a directional sonobuoy acoustic system processor.
Źródło:
Hydroacoustics; 2004, 7; 195-208
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determining the distribution of acoustic field intensity using the sound ray density method
Autorzy:
Gawrysiak, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/331706.pdf
Data publikacji:
2000
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The article presents a numerical method for determining the intensity of sound. The method is based on surface density of sound rays. It assumes that a ray of sound carries a specific acoustic power. As a result, it is no longer necessary to determine intensity in caustics, especially given the fact that intensity determined in caustics using the method employed so far has an infinite value.
Źródło:
Hydroacoustics; 2000, 3; 99-104
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Doppler estimation method for moving target location
Autorzy:
Salamon, R.
Marszal, J.
Powiązania:
https://bibliotekanauki.pl/articles/331983.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The article presents an algorithm for target location based solely on Doppler shift of echo acoustic signals of a moving underwater object. The algorithm is designed for use in multi-static systems for protecting bodies of water from terrorist attacks by divers or submerged vehicles. The original source of signals is a transmitter emitting continuous acoustic waves. The echo signals from moving object are received by hydrophones located at fixed and known points in the water. Doppler shifts are determined from discrete Fourier transforms of hydrophone signals. The proposed iterative algorithm for target location calculates the approximate values of target speed vector and target coordinates which correspond to speed vectors as calculated previously.
Źródło:
Hydroacoustics; 2010, 13; 225-234
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of parametric methods of power spectrum estimation in passive sonar signals classification
Autorzy:
Schmidt, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332824.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper presents the signals classification method based on the parametric spectral analysis as applied to the passive sonar. The system's structure is discussed special emphasis is given to the procedure of features selection in which true poles are chosen. Attached are results of tests carried out to evaluate the applicability of parametric methods of spectral estimation for the purpose of creating acoustic portraits and their classification.
Źródło:
Hydroacoustics; 1999, 2; 145-150
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of distance measurement errors in CW FM sonar with MLS code modulation
Autorzy:
Jedel, A.
Marszal, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/331626.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
CW FM sonar
pseudorandom sequence
Doppler effect
sonar parameters
Opis:
Although 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 confronted with errors which occur in similar sonar without code modulation.
Źródło:
Hydroacoustics; 2017, 20; 75-84
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Principles of computing and displaying the results of detection by underwater systems as part of sound velocity measurements
Autorzy:
Raganowicz, A.
Kilian, L.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/331744.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
hydroacoustics
underwater systems
hydrolocation
hydrocommunication systems
Opis:
The paper presents the upgraded system for measurements of sound velocity profiles and for computing and imaging the terms of detection in different hydrolocation and hydrocommunication systems. Three types of computations made by the system's processors are discussed. The most interesting task is to link the propagation routes and ray density with the parameters of the hydroacoustic system to obtain the desired display of the conditions to detect the signal from the background noises. Presented discussion of methodology of determining detection conditions using different forms of range equation gives a more detailed description of this task. In the next part of this paper the software's display function and necessary settings are specified and discussed. In the end two examples of computed detection conditions images (for active and passive sonar) are shown.
Źródło:
Hydroacoustics; 2003, 6; 267-274
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Continuous wave sonar with hyperbolic frequency modulation keyed by pseudo-random sequence
Autorzy:
Jedel, A.
Marszal, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/331999.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
CW FM
pseudorandom sequence
Doppler effect
matched filtering
Opis:
A 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 object, and its speed. Sounding signal, as patented by the authors, is a combination of Pseudo-Random Sequences (PRS), and elementary signals of Hyperbolic Frequency Modulation (HFM) type. The structure of this signal is aimed at minimizing measurement error. The article presents the idea of a sounding signal of HFM+PRS type, and the results of computer simulations.
Źródło:
Hydroacoustics; 2016, 19; 185-196
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Processing the complex signal in the acoustic processor of a sonobuoy system
Autorzy:
Raganowicz, A.
Rudnicki, M.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332675.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The article presents digital methods for processing the complex signal in the acoustic processor of a sonobuoy. The overall system design and the complex signal are presented. Two alternative methods for signal processing are discussed: in the time domain and in the frequency domain. Block diagrams of the algorithms of both processing methods are included. The problems involved in the practical implementation of data analysis methods are discussed. The problems are produced by the phenomena occurring in the system’s analogue section and by the complexity of the computation related to how powerful the digital algorithms are. The computation errors in both methods are analysed. The advantages and disadvantages of the different signal processing methods are discussed, with emphasis on the practicality of the device. The advantage of the processing method in the frequency domain is explained. Graphic images of the results of both processing methods are included on the example of real signals received during the study.
Źródło:
Hydroacoustics; 2005, 8; 163-170
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Code signals transmission using MFSK modulation in shallow waters
Autorzy:
Zachariasz, K.
Schmidt, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332705.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper presents an acoustic system for the transmission of digital data in shallow coastal waters of which multi-path propagation and intense reverberations are characteristic. To ensure a small error probability of moderate speed transmission, the system uses corrective codes and a technique of incoherent modulation MFSK (Mufti Frequency Shift Keying). To synthesise the transmission signal, estimate the spectrum of the signal received and code and decode the channels, a DSP processor was used. The paper includes the results of a computer simulation in which the system was put to work in the presence of Gaussian noise. The system was tested in shallow coastal waters and the results are discussed in the paper.
Źródło:
Hydroacoustics; 2001, 4; 261-264
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of maximum length sequence in silent sonar
Autorzy:
Marszal, J.
Salamon, R.
Kilian, L.
Powiązania:
https://bibliotekanauki.pl/articles/331898.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
Silent sonars are designed to reduce the distance over which their sounding pulses can be detected by intercept sonars. In order to meet this objective, we can use periodical sounding signals that have low power, a very long duration and wide spectrum. If used in the silent sonar’s receiver, matched filtration ensures very good detection of motionless or slow moving targets. However, it is more difficult to detect echo signals of fast moving targets with Doppler effect causing significant error in target distance measurements. In an effort to find signals that can better resist Doppler effect, maximum length sequence was tested for its application in silent sonar. It has an elementary signal which includes linear frequency modulation. It was demonstrated that the signal produces much better results than those obtained with simple frequency modulation signals.
Źródło:
Hydroacoustics; 2012, 15; 143-152
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
General analysis of broadband signal spatial filtration
Autorzy:
Salamon, R.
Rudnicki, M.
Schmidt, J.
Powiązania:
https://bibliotekanauki.pl/articles/332491.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
acoustics
spatial filtration
underwater acoustic
Opis:
The majority of underwater acoustic systems use narrow band sounding signals. Consequently, there is extensive knowledge on how the relevant spatial filters should be analysed and designed. The difficulty begins when the sounding signal has a broad spectrum. Applying the results of narrow band signal analysis to broadband signals leads to serious errors. The same is true for spatial filtration methods when applied to narrow band signals. The article presents a general method for analysing spatial filters designed for broadband signals. It also gives an assessment of the errors caused by applying spatial filtration methods designed for narrow band signals.
Źródło:
Hydroacoustics; 2003, 6; 251-260
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Underwater communication system for shallow water using modified MFSK modulation
Autorzy:
Schmidt, J.
Zachariasz, K.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332663.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper describes the design and operation of the Modified MFSK system for underwater communication. Its function is to transmit data and commands from ships to underwater objects in shallow coastal waters and lakes. The system was primarily required to ensure energy efficiency in its underwater section and the minimum of transmission errors. The emphasis was on non-linear distortions produced in piezoelectric transducers, an untypical source of errors.
Źródło:
Hydroacoustics; 2005, 8; 179-184
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
OFDM modulation and adaptive equalization for underwater communications
Autorzy:
Kochańska, I.
Lasota, H.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332731.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
Transmission performances of a shallow underwater channel are limited due to multiple reflections of sound waves off the bottom and water surface, and to the non-stationarity caused mainly by water surface movement. In traditional narrowband telecommunication modems complex Decision Feedback Equalizers are used for minimizing the influence of intersymbol interferences caused by multipath propagation of sound waves. The article proposes adapting OFDM modulation and adaptive equalization based on Kalman filtration techniques for use in underwater communications system. The OFDM modulation is used in wideband ADSL telecommunication modems. The Kalman filtration algorithm is used for time-varying processes identification. The techniques were tested in simulation environment with promising results.
Źródło:
Hydroacoustics; 2005, 8; 77-82
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Silent sonar with matched filtration
Autorzy:
Salamon, R.
Marszal, J.
Schmidt, J.
Rudnicki, M.
Powiązania:
https://bibliotekanauki.pl/articles/331754.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
Radars with continuous wave frequency (CW FM sonars) are used in radiolocation as ‘silent radars’. They determine the distance to target by measuring the difference between the frequency of the sounding signal and echo signal. The article presents the principle of operation and parameters of silent CW FM sonars. Target distance determined by these sonars is based on the signal at the output of the matched filter. The Doppler effect is studied in detail to identify its effect on the sonar’s parameters. The results of theoretical calculations are presented together with the results of the sonar’s computer simulation.
Źródło:
Hydroacoustics; 2011, 14; 199-208
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Doppler effect in the cw fm sonar
Autorzy:
Marszal, J.
Salamon, R.
Zachariasz, K.
Schmidt, A.
Powiązania:
https://bibliotekanauki.pl/articles/331758.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
When sonars are used for military purposes they have to ensure unobtrusive operation, afeature that can be potentially secured by ‘silent sonars’ or continuous wave frequency modulation sonars (CW FM sonars). The article presents how these sonars operate and identifies the relations between their parameters. The Doppler effect and its impact on the CW FM sonar are studied to identify how it affects the sonar’s parameters. The results of simplified theoretical calculations are supported with results of computer simulations of a more realistic model.
Źródło:
Hydroacoustics; 2011, 14; 157-164
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł

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