Autor: Zachariasz, K. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

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

Skocz do pozycji: 2.

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

Skocz do pozycji: 3.

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

Skocz do pozycji: 4.

Tytuł:: Method for improving multibeam sonar bearing accuracy
Autorzy:: Leśniak, W.
Marszal, J.
Salamon, R.
Zachariasz, K.
Schmidt, J.
Powiązania:: https://bibliotekanauki.pl/articles/332790.pdf
Data publikacji:: 2009
Wydawca:: Polskie Towarzystwo Akustyczne
Tematy:: multibeam sonar
sonar bearing accuracy
sonars
Opis:: The paper presents a simple method for improving multibeam sonar bearing accuracy. The principle proposed here is similar to the monopulse method, a solution commonly used in radars and sonars. With no manual or automatic beam rotation, the method offers a substantial reduction in the demand for sonar computational effort. It significantly reduces bearing error for a relatively high signal to noise ratio. The paper gives a boundary value of the output signal to noise ratio which when exceeded satisfactorily improves bearing accuracy.
Źródło:: Hydroacoustics; 2009, 12; 98-108
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 5.

Tytuł:: Multibeam sonar with hexagonal array
Autorzy:: Salamon, R.
Marszal, J.
Kilian, L.
Jedel, A.
Ostrowski, Z.
Raganowicz, A.
Rudnicki, M.
Wofan, Z.
Zachariasz, K.
Powiązania:: https://bibliotekanauki.pl/articles/332250.pdf
Data publikacji:: 1999
Wydawca:: Polskie Towarzystwo Akustyczne
Opis:: The paper presents a multi-beam digital sonar that was designed for monitoring and fish stock assessment in in/and waters. The sonar can also be used as a bottom profiler in lakes, rivers and shallow sea areas. The hexagonal piezoelectric transducer array co-operates with a commutator set. The 32 -channel digital beamformer creates 30 narrow receiving beams in every 60o sector of simultaneous observation. The six sectors cover the whole 360o angle range of the sonar. The beamformer digital signal processing is based on second order sampling of echo signals and the phase-shifting principle of beam deflection. The sonar block diagram, beamformer algorithms, as well as transducers designs are discussed.
Źródło:: Hydroacoustics; 1999, 2; 133-138
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 6.

Tytuł:: Modernization of ASW sonar SQS-56 at Gdansk University of Technology
Autorzy:: Marszal, J.
Schmidt, J.
Salamon, R.
Kilian, L.
Raganowicz, A.
Zachariasz, K.
Ostrowski, Z.
Jedel, A.
Rudnicki, M.
Sidorko, T.
Powiązania:: https://bibliotekanauki.pl/articles/331991.pdf
Data publikacji:: 2010
Wydawca:: Polskie Towarzystwo Akustyczne
Opis:: The fast development of electronic technology and digital signal processing methods makes electronic devices, including sonar systems ones, obsolete very quickly. On the other hand the ships mechanical components including mechanical parts of sonars are operational for a few dozens of years. It makes good opportunity to modernize these devices by using modern electronic devices and new digital signal processing methods with application of existing antenna and mechanical systems. The paper presents the modernization of ASW sonar SQS-56 on the Polish frigate ORP “Kościusko”. The aim of modernization, the new parameters of the sonar and block diagram after modernization are presented.
Źródło:: Hydroacoustics; 2010, 13; 191-196
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

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