Section 7 True and False Echoes on Display 7-4
Relation between Type and Height of Target and Detection Range and RCS
Type of target
Height from
sea surface
(m)
Detection range (NM) RCS (m²)
X band S band X band S band
Sea shore line 60 20 20 50,000 50,000
Sea shore line 6 8 8 5,000 5,000
Sea shore line 3 6 6 2,500 2,500
SOLAS target ship
(>5000GT)
10 11 11 50,000 30,000
SOLAS target ship
(>500GT)
5 8 8 1,800 1,000
Small boat with IMO
standard compatible radar
reflector
4 5.0 3.7 7.5 0.5
Marine buoy with corner
reflector
3.5 4.9 3.6 10 1
Standard marine buoy 3.5 4.6 3.0 5 0.5
10-meter small boat without
radar reflector
2 3.4 3.0 2.5 1.4
Waterway location beacon 1 2.0 1.0 1 0.1
Note
Detection range shown in the above table may greatly decrease depending on the shape of the
target, sea state, weather and radio wave propagation conditions.