Low-Pass
3-Pole
Bessel
Appendix A
Theoretical Transfer Characteristics
Frequency Response
f/fc
(Hz)
Amp
(dB)
Phase
(deg)
Delay 1
(sec)
0
-10
-20
-30
-40
-50
-60
0.10
0.20
0.30
0.40
0.50
-0.027
-0.108
-0.243
-0.436
-0.689
-10.1
-20.1
-30.2
-40.2
-50.3
.279
.279
.279
.279
.279
0.60
0.70
0.80
0.90
1.00
-1.01
-1.39
-1.85
-2.39
-3.01
-60.3
-70.3
-80.2
-89.9
-99.5
.278
.276
.273
.268
.261
2
3
4
5
6
2
3
4
5 6 7
0.1
7 8 1.0
10.0
Normalized Frequency(f/fc)
1.10
1.20
1.30
1.40
1.50
-3.71
-4.47
-5.31
-6.19
-7.12
-109
-118
-126
-134
-141
.252
.241
.228
.214
.199
Delay (Normalized)
0.5
0.4
0.3
0.2
0.1
0.0
1.60
1.70
1.80
1.90
2.00
-8.08
-9.05
-10.0
-11.0
-12.0
-148
-155
-161
-166
-171
.184
.170
.157
.144
.133
2.50
3.00
3.50
4.00
5.00
-16.7
-20.9
-24.6
-27.8
-33.4
-191
-204
-213
-221
-231
.089
.062
.046
.035
.022
0.15
2
3
4
5
6
7
8
1.5
0.1
91.0
6.00
7.00
8.00
9.00
10.0
-38.1
-42.0
-45.5
-48.5
-51.2
-237
-242
-245
-248
-250
.015
.011
.009
.007
.005
Normalized Time (1/f sec)
Step Response
1.2
1.0
0.8
0.6
0.4
0.2
-0.0
1.Normalized Group Delay:
The above delay data is normalized to a corner frequency
of 1.0Hz.The actual delay is the normalized delay divided
by the actual corner frequency (fc).
0
1
2
3
4
5
Normalized Time (1/f sec)
Normalized Delay
Actual Delay =
Actual Corner Frequency (fc) in Hz
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