Stealth in military sonars applications may be ensured through the use of low power signals making them difficult to intercept by the enemy. In recent years, silent sonar design has been investigated by the Department of Marine Electronic Systems of the Gdansk University of Technology. This article provides an analysis of how an intercept sonar operated by the enemy can detect silent sonar sign...

Cavitation inception behind each blade of a rapidly rotating propeller generates intense continuous broadband sound underwater. This sound can be considered as an acoustic signal propagating in the underwater medium where it can be received by a single hydrophone located above the sea floor. Reflections of the sound from the boundaries of the shallow water medium result in multipath arrivals at...

LFM signals are widely applied in radar, communication, sonar and many other fields. received by these systems contain a lot of noise outliers. In order to suppress the interference strong impulse on target realize accurate estimation signal parameters, echo need be filtered. this paper, solve problem poor performance parameter based fractional Fourier transform noise, alpha stable distribution...

With the advent of inexpensive oo-the-shelf sonar ranging units sonar has become a common sensor on mobile robotic platforms. Many diierent algorithms have been proposed to obtain environmental layout and other structural information by integrating sonar measurements from multiple positions and/or sensors. Given perfect distance measurements and telemetry, this integration can be fairly simple....

With the advent of inexpensive o -the-shelf sonar ranging units sonar has become a common sensor on mobile robotic platforms. Many di erent algorithms have been proposed to obtain environmental layout and other structural information by integrating sonar measurements from multiple positions and/or sensors. Given perfect distance measurements and telemetry, this integration can be fairly simple....

With the advent of inexpensive oo-the-shelf sonar ranging units sonar has become a common sensor on mobile robotic platforms. Many diierent algorithms have been proposed to obtain environmental layout and other structural information by integrating sonar measurements from multiple positions and/or sensors. Given perfect distance measurements and telemetry, this integration can be fairly simple....

Fish stocks are among the most endangered components of marine ecosystems. To minimize threats to ecosystems and ensure natural sustainable resource use, monitoring systems must be placed in oceans seas. The Underwater Observatory (UFO) UFOTriNet two projects initiated by several researchers from biology, engineering industry Germany between years 2014 2016 2019 2023, respectively. collect abio...

As opposed to visual imaging, biosonar imaging of spatial object properties represents a challenge for the auditory system because its sensory epithelium is not arranged along space axes. For echolocating bats, object width is encoded by the amplitude of its echo (echo intensity) but also by the naturally covarying spread of angles of incidence from which the echoes impinge on the bat's ears (s...

FM sonar sensors have been used in mobility aids for tile visually-impaired. However, previous FM sonar systems have generated continuous audio signals and rely on the user interpreting them. Our research work is carried out to solve the problem of overloading users of FM sonar system with excessive information by machine interpreting the audio signal. The signal is sampled and Fourier transfor...