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echo
Bridge
Indirect
Indirectecho echo
Figure 4-3 Indirect echoes
4.4 Blind and Shadow Sectors
Funnels, stacks, masts, or derricks in the path of antenna may reduce the intensity of the ra- dar beam. If the angle subtended at the antenna is more than a few degrees a blind sector may be produced. Within the blind sector small tar- gets at close range may not be detected while larger targets at much greater ranges may be detected. See Figure
Vessel taller
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Figure 4-4 Blind and shadow sectors
21
