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Detection of Point Scatterers in Medical Ultrasound
(2021-11-19)
We present an overview of the detection of point scatterers in ultrasound images and suggest strategies for evaluating and measuring the detection performance. We use synthetic aperture Field II simulations of a point ...
Multibeam Echosounder With Orthogonal Waveforms: Feasibility and Potential Benefits
(2021-04-15)
Modern multibeam echosounders (MBE) employ frequency-division techniques (FDT) to ensonify multiple sectors within the same ping cycle. This leads to improved performance in coverage rate, and yaw and pitch stabilization. ...
Spatial coherence of speckle for repeat-pass synthetic aperture sonar micronavigation
(2021-03-31)
Accurate positioning of autonomous underwater vehicles is a major challenge. The long-term drift is problematic if global position updates are not available, and for applications such as repeat-pass interferometry and ...
Data-Driven Autocalibration for Swath Sonars
(2020-12-20)
Sidelobes in swath sonar water column imagery can obscure targets of interest and create erroneous bottom detections. Differences between ideal and actual element responses limit the achievable sidelobe level for practical ...
Challenges of Labelling Unknown Seabed Munition Dumpsites from Acoustic and Optical Surveys: A Case Study at Skagerrak
(2022-05-31)
The disposal of unexploded ordnance (UXOs) at sea is a global problem. The mapping and remediation of historic UXOs can be assisted by autonomous underwater vehicles (AUVs) carrying sensor payloads such as synthetic aperture ...
Modeling the effect of random roughness on synthetic aperture sonar image statistics
(2022-09-02)
A model has been developed to predict the effect of random seafloor roughness on synthetic aperture sonar (SAS) image statistics, based on the composite roughness approximation–a physical scattering model. The continuous ...
Point detection in textured ultrasound images
(2023-02-26)
Detection of point scatterers in textured ultrasound images can be challenging. This paper investigates how four multilook methods can improve the detection. We analyze many images with known point scatterer locations and ...
3D Rendering of Shipwrecks from Synthetic Aperture Sonar
(2021-10-25)
Synthetic aperture sonar (SAS) bathymetric mapping provides centimeter-scale horizontal resolution of the
seafloor. Typically, SAS data has been visualized as 2D images or gridded 2.5D surfaces, but it can also be
plotted ...
Adaptive phase estimation filter in long range synthetic aperture sonar interferometry
(2023-05-15)
Synthetic aperture sonar (SAS) interferometry is a technique for very high resolution imaging and mapping of the seabed. In SAS interferometry, the seabed depth estimation performance is a function of the system, the ...
MIMO synthetic aperture sonar: Benefits and limitations
(2023-01-16)
The use of Multiple Input Multiple Output (MIMO) orthogonally coded waveforms sharing the same bandwidth, has the potential to increase area coverage rate in synthetic aperture sonar (SAS). The disadvantage is cross-talk ...