Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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4-166 Edit Table Menu
SR785 Dynamic Signal Analyzer
In the polynomial format, the curve is described as the ratio of polynomials in s
multiplied by an overall gain factor..
Freq sp s Gain
b s b s b
a s a s a
n
n
n
n
m
m
m
m
.Re .( )
( ... )
...
= ∗
+ + +
+ + +
−
−
−
−
1
1
0
1
1
0
In the pole-zero fomat, the numerator and denominator polynomials are factored
so that the frequency response curve is described by the ratio of the products of
the poles and zeros: To ensure a real impulse repsonse, all complex poles and
zeros only occur in complex conjugate pairs.
Freq sp s Gain
s z s z s z
s p s p s p
n n
m m
. Re .( )
( )( )...( )
( )( )...( )
= ∗
− − −
− − −
−
−
1 0
1 0
In the pole residue format a partial fraction expansion of the pole-zero form is
performed to yield the frequency response as a sum of single pole terms
weighted by residues.
Freq sp s Gain
R
s p
R
s p
R
s p
m
m
m
m
. Re .( )
( ) ( )
...
( )
= ∗
−
+
−
+ +
−






−
−
1
1
0
0
Command: EITM? i, j
Copy Other Table
Copies the curve from the other curve fit table into the table currently being
edite[d. Since this option will erase, the curve currently being edited, the
analyzer will prompt for a confirmation before copying the table data.
Clear Table
Clears all data from the curve table currently being edited. Since this option will
erase the curve currently being edited, the analyzer will prompt for a
confirmation before clearing the table data.
Command: ECLR? i
Enter j
Allows the entry of complex poles, zeros, and residues into the curve tables. To
enter a complex value, enter the real part, then press the <Enter j> Softkey. A 'j'
will appear in the edit window. Now enter the imaginary part.
Complex poles, zeros, or residues only occur as part of complex conjugate pairs.
Thus, if the string 3 j 7 is entered for a pole, for instance, it corresponds to the
term (s-(3+j7))*(s-(3-j7)) in the frequency response.