38
3 Radar Targets and Its Reflecting Properties
Fig. 3.16 Electromagnetic
wave scattering on a cone
where β is attenuation coefficient.
For a finite cone, we can easily obtain:
A =
λ
2 tg
4
α
16π
.
(3.40)
Flat rectangular plate RCS To find a RCS of flat rectangular plate of a × b size
(Fig. 3.17), we can at once use a formula (3.6) which determines a RCS at radiating
from a direction defined by (θ 0 , γ 0 ) angles
A =
4π
λ 2 cos
2
θ 0
a
∫
0
b
∫
0
e
−2 jk(x cos γ 0 +y sin γ 0 ) sin θ 0 dxdy
.
Direct calculations result in the following:
A =
4π
λ 2 a
2 b
2 cos
2
θ 0
sin(ka cos γ 0 sin θ 0 )
ka cos γ 0 sin θ 0
2
sin(kb sin γ 0 sin θ 0 )
kb sin γ 0 sin θ 0
2
.
(3.41)
As we can see, a maximum RCS value exists at vertical observation, when θ 0 = 0,
and its value equals:
Fig. 3.17 Electromagnetic
wave incidence on flat
rectangular plate