Archives of Acoustics, 41, 4, pp. 721–729, 2016
10.1515/aoa-2016-0069

Mutual Clutter Suppression Techniques for FM Sonars

Jacek MARSZAL
Gdańsk University of Technology
Poland

Mariusz RUDNICKI
Gdańsk University of Technology
Poland

Andrzej JEDEL
Gdańsk University of Technology
Poland

Roman SALAMON
Gdańsk University of Technology
Poland

Iwona KOCHAŃSKA
Gdańsk University of Technology
Poland

The article presents methods that help in the elimination of mutual clutter as well as the consequences of two FM sounding signal sonars operating in the same body of water and frequency band. An in-depth analysis of mutual clutter was carried out. The effects of sounding signal differentiation were determined, as was the Doppler effect on mutual clutter suppression. One of the methods analysed is of particular interest in a situation in which collaborating sonars are operating in opposite frequency modulation directions. This method is effective for both linear and hyperbolic frequency modulations. A formula was derived, identifying exactly how much quantities of clutter may be lessened. The work included comprehensive computer simulations and measurements as well as tests in real-life conditions.
Keywords: sonar; signal processing; FM; LFM; HFM; clutter; crosstalk.
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Copyright © Polish Academy of Sciences & Institute of Fundamental Technological Research (IPPT PAN).

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DOI: 10.1515/aoa-2016-0069