Campbell Scientific CR23X Micrologger User Manual
Page 127
SECTION 8. PROCESSING AND PROGRAM CONTROL EXAMPLES
8-17
TABLE 8.11-2. FFT Magnitude and Phase Results 0.25 and 1.25 Hz Signal
BIN #
Hz
FFT Mi
FFT Pi
0
0
0.02303
0
1
0.009766
0.01036
0
2
0.019532
0.00206
180
3
0.029298
0
-99999
22
0.214852
0.00086
185.58
23
0.224618
0.01154
17.952
24
0.234384
0.20321
197.78
25
0.24415
0.62935
17.776
26
0.253916
0.69215*
197.79*
27
0.263682
0.28158
17.801
28
0.273448
0.02592
197.68
29
0.283214
0.00092
21.646
125
1.22075
0.00069
90
126
1.230516
0.04342
270.11
127
1.240282
0.23044
89.979
128
1.250048
0.37302*
270*
129
1.259814
0.23053
90
130
1.26958
0.0435
269.89
131
1.279346
0.00061
82.042
511
4.990426
0.00009
180
TABLE 8.11-3. FFT Power Spectra Results
0.25 and 1.25 Hz Signal
BIN #
Hz
FFT PSi
0
0
1.0859
22
0.214852
0
23
0.224618
0.49212
24
0.234384
84.152
25
0.24415
811.01
26
0.253916
980.79*
27
0.263682
162.4
28
0.273448
1.4764
29
0.283214
0
125
1.22075
0
126
1.230516
3.9369
127
1.240282
108.76
128
1.250048
284.94*
129
1.259814
108.76
130
1.26958
3.9369
131
1.279346
0
511
4.990426
0
PROGRAM
;The first part of this program generates a
;dummy data set that represents two signals
;superimposed on top of each other. One signal
;has a frequency of 1.25 Hz and a zero to peak
;amplitude of 1 while the other signal has a
;frequency of .25 Hz and a zero to peak
;amplitude of 2. The data simulates a sampling
;rate of 10 Hz or a .1 sec scan rate.
;This program generates power spectra FFT
;results with out bin averaging.
;Flag 1 is automatically set once the inst. have
;been executed once.
*Table 1 Program
01:
1
Execution Interval (seconds)
01:
If Flag/Port (P91)
1:
11
Do if Flag 1 is High
2:
0
Go to end of Program Table
;The 2nd through 11th instructions are used to
;generate and combine the 1.25 and 0.25 Hz
;signals for the FFT.
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