Table 2: Overlapping area occurs.

ClassificationDistance to the structureFrequencySwath widthTowfish angleResolution grade

Towfish (①)1.50 m1250 kHz16 mR 70°A
Towfish (②)3.80 m1250 kHz16 mL 20°
(a) Concept of Case  1 (overlapping area)(b) Case  1 sonar data