March 19, 2023
Knowledge & Training
Multibeam Backscatter is a tool used in seafloor characterization, and R2Sonic‘s recent MultiSpectral Backscatter advancement dramatically improves this process. MultiSpectral Backscatter comprises two or more frequencies collected in one-pass using an advanced sonar capable of multifrequency transmissions, either interleaved or simultaneous.
Older sonars can collect Multifrequency Backscatter by passing over the same area multiple times using a different single frequency in each pass, whether using the same or different sonars. The difference between the two definitions above is far more than semantics.
The amount of acoustic energy the seafloor returns to a sonar depends on several factors, including sediment type, sonar frequency, sonar characteristics (radiometric), and grazing angle (geometric). Using different frequencies on the same patch of seafloor results in different backscatter responses enabling better seafloor characterization potential. However, using an older, single-frequency sonar results in a grazing-angle change due to multiple passes, exponentially complicating a potential characterization solution. Using different sonars at different frequencies cannot eliminate the grazing-angle problem even if sonars are normalized to reduce radiometric effects.
MultiSpectral Backscatter, collected with R2Sonic sonars, removes the geometric and radiometric problems inherent with MultiFrequency Backscatter collected by older, less capable sonars regardless of whether or not they are normalized.
March 29, 2023
Many surveys are in areas that are less than ideal for acoustics. These types of areas have seafloors that are soft and comprised mostly of…
coverage   Resolution   Survey
March 29, 2023
MBES and the IHO SP44 Standards for Hydrographic Surveys The International Hydrographic Organisation, based in Monaco, published the 5th edition of Special Publication No 44 Standards for Hydrographic…
coverage   iho   Survey
March 16, 2023
Multibeam echosounders are defined by technical features that are specific to acoustic devices. Some of the technical terms may not initially be intuitive even to surveyors. The…