Multibeam echosounder
Footprint Size
Calculate the nadir footprint dimensions and total area from transmit and receive beamwidths and sonar altitude.
Variables
| BWrx | Receiver (across-track) beamwidth, degrees |
| BWtx | Projector (along-track) beamwidth, degrees |
| D | Sonar altitude (depth to target) |
| Dxt | Footprint across-track diameter = 2D·tan(BWrx/2) |
| Dat | Footprint along-track diameter = 2D·tan(BWtx/2) |
| A | Total footprint area = π·D²·tan(BWtx/2)·tan(BWrx/2) |
Sonar settings
Range: 0.05 – 15
Range: 0.05 – 15
Range: 0.1 – 11,000
Results
Footprint Across-track Diameter
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Footprint Along-track Diameter
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Total Area of Footprint
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These results are informational only. This calculator assumes a nadir (vertical) beam and does not account for beam steering, water-column refraction, or system-specific effects. Footprint dimensions grow with off-nadir angle; use appropriate sonar documentation for outer-beam estimates. MosaicHydro accepts no liability for decisions made based on this tool.
