Campbell CR9000, Instruction Manual

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Section 3. CR9000 Measurement Details
3-21
C H A R T 3 .1
F R E Q U E N C Y R E S P O N S E O F S Y N C F IL T E R O R D E R S 1 - 5
0 .0
0 .2
0 .4
0 .6
0 .8
1 .0
1 .2
0 1 2 3 4 5 6
F R E Q U E N C Y
N O R M A L IZ E D T O (1 /IN T E G R A T IO N T IM E )
REL
RESPONSE
S y n c O r d e r 1
S y n c O r d e r 5
Chart 3.1 shows the response times for the synch filters available for the
CR9058E. As can be seen, the 1rst order sync filter does not filter out the
higher frequency components of the input signal. This could result in higher
frequency signals being aliased back to lower frequencies. While the 5th order
sync filter does a fairly good job filtering out higher order frequencies, the
trade off is that it also attenuates the signal at lower frequencies as can be seen
in Chart 3.2.
C H A R T 3 .2
F R E Q U E N C Y R E S P O N S E O F S Y N C F IL T E R O R D E R S 1 T H R O U G H 5
0 .9 1
0 .9 2
0 .9 3
0 .9 4
0 .9 5
0 .9 6
0 .9 7
0 .9 8
0 .9 9
1 .0 0
1 .0 1
0 .0 0 0 .0 1 0 .0 2 0 .0 3 0 .0 4 0 .0 5 0 .0 6 0 .0 7 0 .0 8 0 .0 9 0 .1 0
F R E Q U E N C Y
N O R M A L IZ E D T O (1 /IN T E G R A T IO N T IM E )
REL
RESPO
NSE
S yn c _ o rd e r_ 1
S yn c _ o rd e r_ 2
S yn c _ o rd e r_ 3
S yn c _ o rd e r_ 4
S yn c _ o rd e r_ 5