SV SLA-PA201, Руководство пользователя

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77
( )
3
2
2
4 4 4
1
1
1 1
1
t
s
H s
s s
Q
ω
ω ω
+
=
+ +
For W.B.Combined this expression is replaced by
( )
4
4
4
1
1
1
t
H s
s
s
ω
ω
ω
= =
+
+
c) Upward step(steepness approximately 6dB per octave, proportionality to jerk)
( )
2 2 2
5
2
5
2
5 5 5 5 5
2 2 2
6
6
6 2
6 6 6 6
1 1
1
1 1
1
s
s s s s
Q Q
H s
s s s s
Q
Q
ω
ω
ω ω ω
ω
ω
ω
ω ω
+ + + +
⎛ ⎞
= ⋅ =
⎜ ⎟
⎝ ⎠
+ + + +
Where
( )
2 1 to 6
n n
f n
ω π
= =
(imaginary angular frequency) 2 s j j f
ω π
= =
The product
( ) ( )
h l
H s H s
⋅
represents the band-limiting transfer function. Its corner
frequencies(intersection of asymptotes) are given by
1
f
and
2
f
.
The product
( ) ( )
t s
H s H s
⋅
represents the actual frequency weighting transfer function for a
certain application.
( )
1
t
H s
=
for frequency weighting
j
W
;
( )
1
s
H s
=
for frequency weighting
c
W
,
d
W
,
e
W
,
h
W
and W.B.Combined. This is indicated by infinity frequencies and absence of
quality factors in Table 1.
The total weighting function is
( ) ( ) ( ) ( ) ( )
h l t s
H s H s H s H s H s
= ⋅ ⋅ ⋅
The weighting curves in annex C show the modulus(magnitude)
H
of
H
versus the frequency
f
in a double-logarithmic scale.
NOTE 1. If the equations are interpreted in the time domain, the imaginary angular frequency
p