Japan Radio Co. JLN-740A, Instruction Manual

Page: 227 / 232

C-3
Appendix C Error due to the deviation from
the irradiation angle reference value
APP C
3
Error by pitching and rolling
When pitching and rolling occur, the results are equal to the case where
δ
in expression in (4)
and expression (5) is replaced with the following:
δ → δ
(t) =
δ
m
sin
ω
t
δ
m
: Maximum deflection angle
ω
: Angle frequency of motion
The average Doppler shift frequency in dual
beams is as follows:
f'
d
= f'
d1
–f'
d2
= 1T
∫
−
2
T
2
T
cos
θ
cos
δ
(t) dt
= 4Vf
0
C cos
θ ⋅
ω
2
π
∫
ω
π
ω
π
−
cos ( δ
m
sin ω t) dt
= 4Vf
0
C J
0
(
δ
m
) (6)
The average error is calculated as follows.
ε δ
m
= 100 {J
0
(
δ
m
) –1} (7)
Figure 4 shows the errors attributed to angles
based on the results indicated above.